Tag Archives: Global Warming

Mark Steyn’s Latest Trick

Uncategorized, , , , , , , ,

UPSATE. The motion has been denied. Rather hilariously, bt the way.

Professor Michael Mann vs. Shock Jock Mark Steyn

You all know about the libel suit filed by Professor Michael Mann against Canadian right wing radio shock jock Mark Steyn. Steyn made apparently libelous comments linking Mann, who is widely regarded as the worlds top non-retired climate scientist, to the Jerry Sandusky scandal. (I don’t know what Steyn was implying but the only link is that both work(ed) at Penn State University!) There are other aspects of the libel suit as well, beyond the scope of this post.

The suit was filed in October 2012. I’m told this sort of law suit can drag on for years, and in this case, Steyn and the other defendants have taken action to delay what seems likely to be a decision against them, so this one might take a bit longer.

ADDED: It has come to my attention that some are arguing that Steyn has been trying to push this suit along while the other defendants are those responsible for the delay. You need to be aware of the fact that early on in the process, Steyn separated himself from the other defendants, and some observers have noted that he has been conducting his side of the process in such a way that has left legal scholars wondering if he has a competent lawyer. I have no personal comment on this. But it remains true that there is no way to separate the discovery part of this process among the parties. In other words, as the different parties in the defense take separate action, they are capable of playing something of a “good cop – bad cop” scenario, and that looks like what they are doing. In any event, Steyn has taken specific delaying action by filing a counter-suit.

Then, on June 1st, yesterday, Steyn’s lawyer requested that the DC Court of Appeals expedite the case.

Why is Steyn suddenly in a hurry to see this court case finished, when until now he has been more interested in delay?

I’m pretty sure the reason is a microcosm of how things are developing in the larger world of fossil fuel industry supported science denial, as well as the larger world of right wing vs. progressive politics.

Mann’s suit is not about arguing about science. He is perfectly capable of going head to head with anybody, even bought and paid for deniers, as he recounts in his book The Hockey Stick and the Climate Wars: Dispatches from the Front Lines.

The suit serves, rather, as a part of a larger effort to combat the ongoing systematic attacks on well meaning and hard working scientists who are just doing their jobs. These attacks, in large part funded by energy industry front groups or “think” tanks such as the Heartland Institute, threaten to cast a chilling pall over over the scientific endeavor itself. Young people going into science careers, especially in certain areas, potentially face future denigrating attacks on their personal lives and character, and potentially career ending frivolous investigations by science deniers in Congress or in other positions of power.

A few months ago we saw shock jock Steyn called by anti-science Senator, failed presidential candidate, and widely detested Ted Cruz, in what can only be described as a three-ring circus of climate science denial. Steyn used his time before congress to argue his case in the Mann law suit, and to blow a racist dog whistle or two denigrating two of the DC Appeals court judges, Judges Natalia Combs Greene and Vanessa Ruiz. I only mention this because it gives background on Steyn and the overall anti-science movement. See Mark Steyn, The DC Appeals Court, and Congress for a detailed discussion of that).

Ask not for whom the bell tolls, science denier.

A couple of years ago, in Minnesota, a Republican House and Senate passed a bill to create a constitutional amendment making same sex marriage illegal. Why an amendment and not a law? It was generally thought at the time that the Republicans assumed that if Democrats took power (which they did right after that), that the law would be toast. A constitutional change is harder to undo. But there was another strategic reason to go for the change to the State’s Constitution, a reason that is directly parallel to Mark Steyn’s current strategy vis-a-vis the Mann law suit.

The Republicans legislators voted close to 100% in favor of banning same sex marriage in Minnesota, the Democrats voted close to 100% against it. The amendment then became a ballot issue, which was fought over for months in the public forum, and then, resoundingly defeated by the people of Minnesota. That was one of the first and key moments in the Great Domino Knockover ending legislation and constitutional restriction against same sex marriage.

So what?

Here’s what. During the public fight over the ballot amendment, I went to a fund raiser hosted by a colleague. At that fund raiser, a member of the Minnesota House told a story.

Every year, pages are brought to the legislature to work the legislative session. These are high school seniors representing every single district in the state, so they are geographically evenly distributed across liberal and conservative enclaves and regions. Urban Minneapolis is very liberal. One of the Urban members of the US Congress, Keith Ellison, is an African American Muslim Bernie Sanders Supporter. One of the non-urban members of the US Congress, for several years, was Tea Party co-Founder Michele Bachmann. So, you get the picture.

When the pages are first brought in, there are orientation activities of various sorts. One of the orientation activities is to poll the pages on various political questions. The pages, from Michele Bachmann’s district, Keith Ellison’s district, and everywhere else, were polled that year on their position on the Same Sex Marriage Banning Amendment. How did that shake out?

Every single page was opposed to the amendment. Every. Single. One. They were all about 18 years old.

The Republican strategy to make same sex marriage unconstitutional, instead of merely illegal, was motivated by a correct reading of the state’s demography. The next generation of Minnesotans was not going to have this sort of discrimination. Every year the state’s population would be increasingly in favor of marriage freedom and opposed to repression of LGBT people. The conservatives in the State Legislature had to act quickly to codify their systematic hatred before everyone else grew up.

Grumpy Old Men

Grumpy Old Men isn’t just a movie set in Minnesota. It is a key part of the demographic base for science denial.

At about the same time that the marriage amendment was being proposed and eventually put down in Minnesota, John Cook, Dana Nuccitelli, Jim Powell and their colleagues were turning out the Climate Consensus Project. This project paralleled and replicated earlier research, but using a different approach. The upshot of that collective research was to show that nearly, but not exactly, 100% of climate scientists and the peer reviewed papers that address climate change, all agree: Climate change is real, and human caused.

The actual studies are more complex and nuanced than that, but for now there is one conclusion that I want you to focus on. Something less than three percent of the people who’s opinion matter in the scientific world, those who are verified experts in this area, continued to question the legitimacy of human caused climate change in the face of overwhelming scientific evidence.

Who are these people?

We know from work by John Mashey, that science deniers with actual scientific credentials are like conservative Minnesota legislators.

Mashey examined the characteristics of individuals who opposed, from within, the American Physical Society’s position on the reality of human caused climate change. The opposition took the form of a petition signed by less than a half percent of the 47,000 member of the society. That subset of APS members tended to be in subfields that did not focus on climate science. But most interesting here is the demography of that group.

Mashey showed that the signers of the anti-science petition were, as a group, older and more likely to be retired than the APS members in general.

Of the 119 signers, 102 (86%) were born before 1950, compared to about 40% for overall APS. This is a strong effect, and cannot be due to “retired scientists are finally free to tell the real truth”, given that only one plausible climate scientist is a signer, and he is not retired.

In addition, there is evidence that as this non-representative sample of APS members was recruited to sign on, efforts were made by the petition organizers to find older or retired individuals, dust them off, and get them on board.

Like the situation with same sex marriage in Minnesota, the demographics are changing. That few percent that the Consensus Project and similar research identifies as not being on board with climate science probably represents the grumpy old men who are disappearing at the usual rate, like they do. The scientists who understand climate science and make up the bulk of the consensus are not only more involved in actual climate science, but also, are of the current generation of active scientists.

They are old. And, therefore, becoming less numerous with every passing day, with every tolling of the bell.

Who is Steyn’s dead guy?

A key reason given by Steyn and his lawyer for expediting the Mann lawsuit is that key witnesses that would support Steyn’s case may die off before the case comes to court.

According to the “request for expedited hearing” filed by Steyn’s lawyer,

Steyn’s expert witnesses are older than Mann’s; time affects them more. Many of Steyn’s expert witnesses are emeritus professors and comparatively advanced in years, being of an age and eminence that enables them to stand against the bullying and intimidation that prevails in climate science. Therefore, the passage of time is not an unimportant thing. Indeed, one of Steyn’s proposed witnesses has, in fact, died while this interlocutory appeal has been with the appellate court.

The brief does not mention which witness died. Any guesses?

Apparently, Steyn and his lawyer had a “holy crap” moment, realizing that if this law suit does not come to court sooner than later, there would be precious few individuals prepared to serve as witnesses in favor of an idea that about to get pulled off life support.

Time is running out for Steyn. Over time, those who question the validity of well established science are likely to change their minds once they get the proper information, realize that their position is laughable and walk away from denialism simply because it is embarrassing, or, apparently, die.

But it is more important that time is running out for the planet, and for the up and coming generation that is being handed a ruined environment.

Even as I write these words a news alert comes across my desk: “Europe floods: 10 dead amid fears of fresh heavy rainfall,” referring to flooding in France and Germany. Flooding in Texas over the last few days, and continuing, has taken at least a half dozen lives. To someone like Steyn, and his out of touch geriatric witnesses, this is small change. A half a dozen people here, a half a dozen people there. And that is exactly the problem and exactly why Mann’s lawsuit is important and valid. Climate denialism is, as a movement, effectively sociopathic. And, as individuals in that movement realize that, they tend to wander off.

The Atlantic Hurricane Season started yesterday and there are already two named storms. Major fires in the Canadian Rockies, the decline of iconic species such as the North American Moose, coral bleaching, the spread of very nasty diseases out of the tropics, record high temperatures, the Syrian refugee crisis, are all linked to climate change to some degree, often very directly, sometimes more tenuously. (See this for a current accounting of climate disasters ongoing.)

Extreme variability in precipitation patterns, including both short and long term droughts and major rain or snow fall events, has been linked pretty directly to anthropogenic global warming. Heat waves and sea level rise due to melting glaciers, and changes in ocean chemistry, are direct measures of increasing surface heat. Weather and climate are two faces of the same coin, different in scale with weather being in one spot and on one day, and climate being weather long term and everywhere. If we change climate, which we have, we change weather, and thus we affect day to day live, the food supply, the global economy, and global health.

An Evangelical Christian Republican View of Climate Change

Uncategorized, , , , , ,

Trending wetter with time: weather never moves in a straight line, but data from NOAA NCDC shows a steady increase in the percentage of the USA experiencing extreme 1-day rainfall amounts since the first half of the 20th century. Photograph: NOAA NCDC

My Apology to Paul Douglas

I admit that I do a lot of Republican bashing. I’m a Democrat, and more than that, I’m a partisan. I understand that a political party is a tool for grass roots influence on policy, if you care to use it. The Democratic party platform, at the state and national level, reflects my policy-related values reasonably well, and the Republican approach is largely defined as supporting the opposite of whatever the Democrats say, even when Democrats come up with a policy that is closely based on a previously developed Republican policy. So, my hope is to see the Democratic caucus in the majority, in both houses of my state legislature, and both houses of the US Congress. And a Democratic President. This is the only way that the policies I see as appropriate and important are advanced, and the anti-policies put forth by the reactionary party, the Republicans, are not.

So, with respect to elected officials, I will always oppose Republicans and always support Democrats. That includes opposing “Reasonable Republicans” (an endangered species) and, not happily, supporting Red Dog Democrats. This is necessary because of the necessity of a majority caucus in each legislative branch. (You probably know this, but the majority party gets to call the shots, run committees, etc.) At some future date, when Democratic majorities are not as tenuous, I may change that approach, but not now.

If key policy orientations for key issues tended to find cross-party support, I would not be so much of a partisan. But that is not what happens these days in government. My partisanship is not a choice, but a necessity required by Republican reactionary philosophy among elected officials.

So, that is my explanation — not excuse, but explanation — for my Republican bashing, a behavior that is one side of a coin. The obverse is, obviously, Democratic cheerleading.

And, with that as background, I sincerely apologize to my friend Paul Douglas.

Minnesota Nice Weather

Paul is one of the country’s top meteorologists.

When I was about to move to Minnesota, I flew out to find an apartment for my family, and get the feel of the landscape. I stayed in a hotel in the near western suburbs, and spent each day looking at apartments, and checking out driving times between various neighborhoods and the University of Minnesota. Every evening I pick up the local papers to peruse them while watching the local news, because that is a good way to get to know a place.

One day I was out driving around, lost, somewhere near downtown on this mess of highway that made no sense to me. The sky had been filled since early morning with enormous thunderheads, the kind I had seen previously in the Congo, but rare in Boston, where I was living at the time. Suddenly, a huge thunderstorm passed overhead, with hail, and the road filled with water, forcing me to pull off for a few minutes to avoid hydroplaning. After the storm had passed, I drove back out onto the highway, and witnessed an amazing sight.

First, I should note that in Minnesota, you can see the sky for great distances because it is relatively flat here. Minnesotans don’t think of Minnesota as flat, and compared to Kansas, it isn’t. But it is compared to my previous homes in Boston or upstate New York. I remember thinking that day that Minnesota counted as “Big Sky Country” in its own way. Minus the Rocky Mountains.

Anyway, the sky was being big, and the view was filled with more thunderheads. But off to the northeast was a huge horizontally elongated cloud. It was at about the same elevation as the lower parts of the nearby thunder clouds, longer in its longest dimension than a good size thunder storm, but shaped more like a giant cigar. And it was rotating, rapidly, like a log rolling down hill. (Except it wasn’t really going anywhere.)

I thought to myself, “This is amazing. I wonder if the people of Minnesota appreciate how spectacular and beautiful is their sky and weather, which they observed every day!”

Later that evening, I got back to my motel and switched on the news. The top news story that day, it turns out, happened to be the day’s thunderstorms, so the anchor handed off the mic to the meteorologist.

I had made an error in thinking that the people of Minnesota might be inured to spectacular thunder storms and giant rotating cigar shaped clouds. The weather reporter was showing news footing of the sky, including the rotating cigar shaped cloud I had witnessed. He told the viewers that the storms today were especially spectacular, and that this giant rotating cigar thing was a special, highly unusual weather event. He named it, calling it an arcus cloud, and noted that it was effectively similar to a tornado, in terms of wind speed and destructive potential, but that this sort of cloud rarely touched down anywhere.

(This sort of arcus cloud is a roll cloud, very rare in continental interiors, though somewhat more common in coastal areas.)

That year there were many thunderstorms in the Twin Cities. The following year as well. There were also a lot of tornadoes. All of the tornadoes I’ve ever seen with my own eyes (small ones only) were during that two year period, including one that passed directly overhead and eventually damaged a tree on the property of a house we had just made an offer on, subsequently moving along a bit father and menacing my daughter’s daycare.

An Albino Unicorn Observes Weather Whiplash

I’m pretty sure, if memory serves, that some time between my observation of the arcus cloud and the Saint Peter tornado, Paul Douglas moved from Chicago back to the Twin Cities, where he had perviously been reporting the weather.

Paul Douglas will tell you that during this period he, as a meteorologist covering the midwest and plains, started to notice severe weather coming on more frequently than before. When such a thing happens a few years in a row, one can write that off as a combination of long term oscillations in weather patterns and random chance. But when the fundamental nature of the weather in a region shifts and such normally rare events become typical, then one might seek other explanations. Climate change, caused by the human release of greenhouse gasses into the atmosphere, is ultimately the explanation one is forced to land on when considering widespread, global (and Minnesotan), changes in weather patterns.

Paul describes himself as an “albino unicorn.” This is not a reference to a horn sticking out of his nose, or atypical pigmentation. Rather, he recognizes that as a Republican who fully accepts science, and in particular, the science of climate change, he is an odd beast. It is worth noting that Paul is also an Evangelical Christian. There are not many Evangelical Christian Republicans who understand and accept science. There are probably more than the average liberal or progressive Democrat thinks there are, because such rare beasts need to keep their heads down in many contexts. But Paul is the rarer subspecies of albino unicorn that simply refuses to do that. He speaks openly and often about climate change, giving talks, frequent interviews (like this one with me), and regular appearances on various news and commentary shows.

Paul currently runs this company, and writes an excellent weather blog here. His weather blog focuses on Minnesota weather, but it should be of interest to everyone in the US and beyond, because he also catalogues current extreme weather events globally, and summarizes current scientific research on climate change.

You are probably familiar with The Guardian’s blog on climate change, “Climate Consensus – the 97%” written by my fellow Minnesotan John Abraham, and Dana Nuccitelli, author of Climatology versus Pseudoscience: Exposing the Failed Predictions of Global Warming Skeptics. The current post on that blog is a guest post by Paul Douglas: Meteorologists are seeing global warming’s effect on the weather.

The graph at the top of this post is featured in Paul’s writeup, so go there and read the background. If you happen to know Donald Trump, suggest to him that there is an interesting write-up on climate change by an Evangelical Christian Republican, which he should read in order to get the Evangelical Christian Republican view on the topic!

Paul writes:

In a day and age of scammers, hackers, hucksters and special interests it’s good to be skeptical. You should be skeptical about everything. Some of the biggest skeptics on the planet are scientists. In fact, science is organized skepticism. Climate and weather are flip-sides of the same coin; everything is interconnected. Climate scientists tell us the climate is warming and meteorologists are tracking the symptoms: freakish weather showing up with unsettling regularity. Even if you don’t believe the climate scientists or your local meteorologist do yourself and your kids a favor. Believe your own eyes.

Paul saw the signature of anthropogenic climate change in the weather he was analyzing and reporting on long before climate scientists began to connect the dots with their research. Many of the dots remain unconnected, but the association between observable changes in the climate system and changes in the weather is now understood well enough to say that it is real. I believe that the recent uptick in acceptance of climate science by Americans is partly a result of the impossible to ignore increase in severe weather events, especially flooding and major storms. The most severe heat waves have, so far, occurred in other countries, but we do get the news and we do know about them.

Check out Pauls’ Guardian writeup where he connects the dots for you, and makes a strong case that we need to put aside denialism of the science.

The Glaciers Will Melt, The Sea Will Rise Up

Uncategorized, , , , ,

Sea levels are going to rise

The amount of carbon dioxide in the Earth’s atmosphere directly and indirectly determines the sea level. The more CO2 the higher the sea level. The details matter, the mechanism is complex, and as CO2 levels change, it takes an unknown amount of time for the sea level to catch up.

The present day level of CO2 is just over 400ppm (parts per million). For thousands of years prior to humans having a large effect on this number, the level of atmospheric CO2 was closer to 250. Human release of CO2 into the atmosphere by the burning of fossil fuel, and other human activities, are responsible for this difference. We expect the atmospheric concentration of CO2 to rise considerably by the end of the century. It is remotely possible that by 2100, CO2 will be about where it is now, but only if a significant effort is made to curtail its release. If nothing is done about the release of CO2 by human burning, the number will exceed 1000ppm by 2100. Reasonable estimates assuming the most likely level of effort to change the energy system put CO2 at somewhere around 600 to 700ppm by the end of the century.

So, it is reasonable to ask the question, what is the ultimate sea level likely to be with atmospheric concentrations of CO2 between 500 and 700ppm?

How long will sea level rise take?

Once the CO2 is in the atmosphere, it stays there for a very long time. So, if we curtail emissions and manage to keep the atmospheric CO2 between 500 and 700, that number will not drop for centuries. So, again, we have to expect sea levels to rise to whatever level is “normal” for an atmospheric concentration of CO2 between 500 and 700ppm. That is a conservative and perhaps even hopeful estimate.

A fair amount of research (but not nearly enough) has been produced over the last two or three years with the aim of estimating how fast and to what degree the major glaciers of the earth (in Greenland and Antarctic) will melt with global warming. In the long view, all of this research is irrelevant. The simple fact is that with higher CO2 levels, a lot of that ice will ultimately melt, and sea levels will ultimately go up. But in the short and medium term, that research is some of the most important research being done in climate change today, because it will lead to an understanding of the time frame for this rise in sea level.

None of the research I have seen satisfactorily estimate this rate, but with each new research project, we have a better idea of the process of deterioration of major glaciers. As this research progresses, the glaciers themselves are actually deteriorating, but they are only beginning to do so. As the research advances, we will get a better theoretical model for glacial deterioration. As the glaciers deteriorate we will have increasing opportunity to calibrate and test the models. I expect that in a few years from now (ten or twenty?) there will be active competition in the research world between theoretically based models and empirical observations to provide rate estimates for sea level rise. But at present we have mainly theory (the observational data is important but insufficient) and the theory is too vague.

A new paper came out this week that explores the process of deterioration of a major part of the Antarctic glacial mass. I’ll summarize this research below, but the main point of this post is to put all of this recent research in the context outlined in the first few paragraphs above. How much sea level rise can we ultimately expect, even if we have no good idea of when it will happen?

It may not matter how fast sea level rises

Uncertainty about the time frame for glacial melt is important for all sorts of practical reasons, but an interesting aspect of human culture and economy obviates that uncertainty, and does so rather ironically. In our economic system, we value things in many different ways. There are things that have great value in part because they are fleeting, rare, or ephemeral. People pay a lot for a great meal that is gone in 20 minutes, a random act of erotic pleasure, two minutes of terror on a carnival ride, or a small pile of white powder.

But we also pay good money for things because of their long term value. A classic problem in economics asks why a man (it’s always a man) in, say, Egypt, is willing to plant and tend hundreds of date tree saplings, knowing full well that the first fruit will not be provided until long after his own death. The reason, of course, is that his son will inherit these trees. Of course, his son is not likely to gain much from these trees because they will still be young and small. So the value of this grove of trees to his son is based mostly on the value to the son’s son. And so on.

This is how we place value on real estate. The main reason that a home you might consider buying today is of a certain value is that you can sell it for a similar or greater value in the future. The fact that short term fluctuations may destroy a good part of that value over the next decade does not obviate the longer term value of the property.

Some of the most valuable property in the US and in many other countries is within spitting distance of the ocean. The ocean itself adds this extra value either as commercial or industrial space, or as high-end domestic or tourist space.

If sea level rise sufficient to destroy that property was imminent, so the property would be destroyed this year, then the value of that property would be zero. But considering that the value of the property is always based in large part on the future sale value, then sea level rise sufficient to destroy it, but that won’t happen for a century, is sufficient to destroy that long term component. If you acquire property today that will eventually be flooded by the sea, you might think you own it. But really, you are renting it. When the sea rises up and inundates the lot, the lease is up.

So, in a way, it does not matter how long it will take the sea to rise, say, 10 meters. Any property that would be destroyed with sea level rise is, right now, worth less than a market ignorant of this inevitability would price it.

Why is it hard to estimate the rate of sea level rise?

Most of the ice in Antarctica is sitting on the interior of the continent, well away from the sea. But much of this ice is held in large catchments, or valleys, that have outlets to the sea. Those outlets are plugged with huge masses of ice, and that ice is, in turn, held in place by grounding lines, where part of the ice sits tenuously on the bedrock below sea level.

Behind the groundling lines, upstream, are valleys of various depths, but deeper than the point of grounding itself. It is thought that if the ice sitting on the grounding line falls apart, the plug of ice will deteriorate fairly quickly until a new grounding line, perhaps many kilometers upstream, is established. But that grounding line may be subject to deterioration as well, and eventually, the outlet valley that connects the interior catchment to the sea becomes open water, and the ice in that catchment can also deteriorate, and fall into the sea mainly in the form of ice bergs regularly calved off the glacier, like we see today in Greenland.

The main cause of global warming induced melting of the ice near the groundling line is warm water. The surface of the Antarctic glaciers does not melt very much from warm air, because the air over the southern continent is rarely above freezing. However, with global warming, we expect air temperatures to go above freezing more commonly. This would contribute to thinning of the ice over the grounding lines, and thus, more rapid breakdown of the plug holding most of the ice in place.

It is thought that when a grounding line fails, and the plug of ice begins to move into the ocean, steep cliffs are formed alongside the deteriorating ice. This would cause the ice behind the cliffs to destabilize, causing ice bergs to form at a very high rate. Also, the interior ice, in the large catchments, is generally thought to be unstable, so when Antarctic glaciers reach a certain point of deterioration, those glacial masses may deteriorate fairly quickly.

Each of these steps in glacial deterioration is very difficult to model or predict, as these phenomena have never been directly observed and the process involves so many difficult to measure mechanical and catastrophic events.

Upstream from the grounding line, though the horizontally flowing glacial masses in the plug, and up into the catchments, the sub-ice topography is complex and will likely control, by speeding up or slowing down, glacial deterioration. It is thought that many of the glacial masses that make up Antarctica’s ice have melted and refrozen numerous times, and glacial ice has moved towards the sea again and again, over the last several million years. As glacial ice moves along it carves out valleys or deposits sediments in a complex pattern, which then determines subsequent patterns of ice formation or deterioration. It is reasonable to assume that each time the glaciers melt and reform, the terrain under the ice becomes, on average, more efficient in allowing the movement of ice towards the sea. Thus, any estimate of the rate of glacial movement and deterioration based on past events is probably something of an underestimate of future events.

This has all happened before

We know that the world’s glaciers have melted and reformed numerous times from several sources of evidence, and that this has been the major control of global sea level, as water alternates between being trapped in glacial ice and being in the oceans.

We know that global sea levels have gone up and down numerous times, because we see direct evidence of ancient shorelines above current shorelines, and we have direct evidence that vast areas of the sea have been exposed when glaciers were at maximum size.

We can also track glacial growth and melting by using oxygen isotopes that differ in mass. Glaciers tend to be made of water that contains a relatively high fraction of light oxygen, while the ocean water tends to have relatively more heavy oxygen. This is because water molecules with heavy oxygen are slightly less likely to evaporate, so precipitation tends to be be light. Glaciers are ultimately made of precipitation. There are organisms that live in the sea that incorporate oxygen from sea water into their structures, which are then preserved, and can be recovered from drilling in the deep sea. By measuring the relative amount of heavy vs. light oxygen in these fossils, controlling for depth in the sea cores, and dating the cores at various depths, we can generate a “delta–18” (short for “Difference between Oxygen–18 and Oxygen–16”) curve. This is an indirect but very accurate measure of how much of the world’s free water is stuck in glaciers at any given moment in time.

The Delta–18 curve for Earth for the last ca 800,000 years looks like this:

Oxygen Isotope Levels Over Time

(from here

That curve is made from deep sea curves, and unfortunately, the deep sea curves don’t go back far enough in time to get a good idea of glacial change, at this level of detail, for enough time to really get a handle on the full history of glaciation. But by piecing together data from many sources, and careful use of dating techniques like Paleomagnetism, it is possible to get a long view of Earth history. The following graphic (from The Panerozoic Record of Global Sea-Level Change by Miller et al, Science 310(1293)) shows the general pattern.

Sea Levels Over Millions Of Years

The Earth was warmer many tens of millions of years ago (before the modern ecology, flora, and fauna evolved), fluctuating between warm and very warm over long periods of time. Then, in recent millions of years, things cooled down quite a bit. It is during this cooler period that the modern plants and animals became established, and that humans came on the scene.

Here’s what I want you to get out of this graphic. Look at the purple line. These are global sea levels after about 7 million years ago. Note that sea levels were often tens of meters higher than they are today (relative to the zero line on this graph).

Now have a look at this graph.

Atmospheric CO2 and Sea Levels Over Time

This is a very complicated graph and in order to understand all of the details you’ll have to carefully read the original paper. But I can give you a rough idea of what it all means.

Each of the four graphics is a different way that paleoclimatologists can look at the relationship between atmospheric CO2 and sea level, and compile a large number of data points. Think of each graphic as a metastudy of CO2 and sea level using four independent approaches and all of the data available through about 2012.

In each graph, note the dotted lines. The vertical dotted line is CO2 at 280ppm, taken as the pre-industrial value (though we know that is probably an overestimate since lots of CO2 had been released into the environment by human landuse and burning prior to the presumed beginning of the “pre-industrial” period). The horizontal line is the present day sea level.

Each of the little symbols on the graph is a different observation of CO2 and sea level from ancient contexts, using various techniques and with various paleoclimate data sets over many millions of years.

Note that at the point where the pre-industrial CO2 and the modern sea level intersect, there are many points above and below the line. This is partly error or uncertainty, and partly because of the time lag between CO2 reducing over time and subsequent growth of glaciers. It takes many thousands of years for these glaciers to grow (they melt much more quickly).

As we go from pre-industiral levels of CO2 through the values of interest here, getting up to 600 or more parts per million, past sea levels are generally higher than the present. In fact, at 400ppm, where we are now, sea levels are substantially higher than the present for almost all of the data points. This probably means the following, and this is one of the most important sentences in this post, so I’ll give it its own paragraph:

Present day carbon dioxide levels are associated with sea levels many meters above the present sea level; the current Earth’s atmosphere is incompatible with the current Earth’s glaciers, and those glaciers will therefore become much smaller, and the sea level much higher, even if we stop adding CO2 to the atmosphere this afternoon.

The other interesting thing about this graph is that above about 600ppm atmospheric CO2, the sea levels observed in the past are even higher, way way higher. These are time periods when there was virtually nil glacial ice on either pole, or elsewhere. This is what the Earth looks like when virtually all the ice is melted. This is the Earth that we are likely to be creating if we allow CO2 levels to approach 1000ppm, and the track we are on now virtually guarantees that by the end of the century.

One might assume that we would never let that happen, that we would solve this problem of where to get energy without buring fossil fuel before that time. But at this very moment there is about a 50–50 chance that the next president of the United States will be a man who believes that climate change is a hoax. In other words, it is distinctly possible that one of the largest industrial economies in the world, and a globally influential government, will ignore climate change and forestall the transition to clean energy until 2024.

Look at this graph. The upper line, “High Emissions Pathway (RCP 8.5)”

Future CO2 levels

I now officially rename the “Trump Line.”

So, how high will the sea levels rise?

There really is little doubt that we are looking at several meters of sea level rise given our current CO2 levels. How many meters?

From the paper cited above: “…our results imply that acceptance of a long-term 2 degrees C warming [CO2 between 500 and 450 ppm] would mean acceptance of likely (68% confidence) long-term sea level rise by more than 9 m above the present…”

Personally, I think this is a low estimate, and the actual value may be more like 14. Or more. There is no doubt that we are going to add many tens of ppm of CO2 to the atmosphere over the next few decades even if we act quickly on changing our energy system, and the chances are good that we will be close to 600. This is at the threshold, based on the paleodata, between lots of glacial ice melting to produce 9, 15, or so levels of sea level rise, and nearly all of the glacial ice melting, to produce sea level rise of over 30 meters.

And, if we follow the Trump Line we’ll reach that level of CO2 well before the end of the century.

Again, the question emerges, how long will it take for sea level to rise in response to the added CO2? Than answer, again, is we don’t know, but in important ways, as noted above, it matters less than one might think.

We are probably going to be stupid about sea level rise

There is another aspect of this problem that is underscored by the most current research, and several other research projects. For the most part, the glaciers will not melt evenly and steadily. This is not a situation where we can measure how much ice melts off every decade, and extrapolate that into the future. What we now know about the big glaciers is that they will almost certainly deteriorate a little here and a little there, then suddenly and catastrophically break down, losing a huge amount of their ice to the sea, then for a period of time continue to fall apart at a lower but still accelerated rate, which will slow down after a while until some level of stability is reached. Then, that stability will remain threatened for a period of time until the next catastrophic collapse of that particular glacier.

Also, as noted in the research project I’ll report below, some of these catastrophic steps that happen later in the process may in some cases be the largest.

Here’s why this is important. Honestly, do you even believe that we have already added enough CO2 to the atmosphere to flood all of the planet’s major coastal cities, and major areas of cropland, and that this can’t be stopped? Isn’t that a bit extreme, alarmist, even crazy? Of course it seems that way, and even if you accept the science, a significant part of you will have a very hard time accepting this conclusion.

Those in charge of policy, the people who can actually do something about this, are not immune to this sort of cognitive dissonance. So, as long as the glaciers are only adding a foot a century instead of a foot a decade, the massive melting scenario will be on the back burner. Then, of course, one or two or more of these glaciers are going to lose their grounding lines within a few years of each other, and start to add huge amounts of water to the sea, and everyone will freak out and catastrophic coastal flooding will happen, and then the whole thing will slow down and more or less stop for a period of time, and once again, the prospect of sudden and major sea level rise will return to the back burner.

Then it will happen again.

New research on glacial collapse

OK, about that new research. Here is the abstract:

Climate variations cause ice sheets to retreat and advance, raising or lowering sea level by metres to decametres. The basic relationship is unambiguous, but the timing, magnitude and sources of sea-level change remain unclear; in particular, the contribution of the East Antarctic Ice Sheet (EAIS) is ill defined, restricting our appreciation of potential future change. Several lines of evidence suggest possible collapse of the Totten Glacier into interior basins during past warm periods, most notably the Pliocene epoch, … causing several metres of sea-level rise. However, the structure and long-term evolution of the ice sheet in this region have been understood insufficiently to constrain past ice-sheet extents. Here we show that deep ice-sheet erosion—enough to expose basement rocks—has occurred in two regions: the head of the Totten Glacier, within 150?kilometres of today’s grounding line; and deep within the Sabrina Subglacial Basin, 350–550?kilometres from this grounding line. Our results, based on ICECAP aerogeophysical data, demarcate the marginal zones of two distinct quasi-stable EAIS configurations, corresponding to the ‘modern-scale’ ice sheet (with a marginal zone near the present ice-sheet margin) and the retreated ice sheet (with the marginal zone located far inland). The transitional region of 200–250?kilometres in width is less eroded, suggesting shorter-lived exposure to eroding conditions during repeated retreat–advance events, which are probably driven by ocean-forced instabilities. Representative ice-sheet models indicate that the global sea-level increase resulting from retreat in this sector can be up to 0.9?metres in the modern-scale configuration, and exceeds 2?metres in the retreated configuration.

Chris Mooney has written up a detailed description of the research including information gleaned from interviews with the researchers, and you can read that here. In that writeup, Chris notes:

Scientists believe that Totten Glacier has collapsed, and ice has retreated deep into the inland Sabrina and Aurora subglacial basins, numerous times since the original formation of the Antarctic ice sheet over 30 million years ago. In particular, they believe one of these retreats could have happened during the middle Pliocene epoch, some 3 million years ago, when seas are believed to have been 10 or more meters higher (over 30 feet) than they are now.

“This paper presents solid evidence that there has been rapid retreat here in the past, in fact, throughout the history of the ice sheet,” Greenbaum says. “And because of that, we can say it’s likely to happen again in the future, and there will be substantial sea level implications if it happens again.”

And, from the original paper (refer to the graphic below):

The influence of Totten Glacier on past sea level is clearly notable, but for any particular warm period it is also highly uncertain, because the system is subject to progressive instability. Our results suggest that the first discriminant is the development of sufficient retreat to breach the A/B-boundary ridge. This causes an instability-driven transition from the modern-scale configuration to the retreated configuration. Under ongoing ice-sheet loss, the breaching of Highland B causes further retreat into the ASB. Each of these changes in state is associated with a substantial increase in both the absolute and the proportional contribution of this sector to global sea level.

Figure 1 from Aitken et al. "Repeated large-scale retreat and advance of Totten Glacier indicated by inland bed erosion. The sea is to the north, the inland glacial basin is to the south.
Figure 1 from Aitken et al. “Repeated large-scale retreat and advance of Totten Glacier indicated by inland bed erosion. The sea is to the north, the inland glacial basin is to the south.

This is a video by Peter Sinclair that dates to a bit earlier than this research was published, but covers the same issue:

Many of the interesting natural areas, like national parks or preserves, have a museum. In the museum there is often a geology exhibit, showing the changes in the landscape over long periods of time. Almost always, there was a period of time when the place you are standing, looking at the exhibit, was part of a “great inland sea.”

Let me introduce you to my little friend … the Great Inland Sea. Because it is coming back.

The_Ancient_Inland_Sea_Is_Coming_Back

Climate Change and Birds in North America and Europe

Uncategorized, , , , ,

I’ve got a new post up at 10,000 Birds on a study looking at changing populations of several hundred common species of birds in Europe and North America (mainly the US).

The two subcontinents exhibit dramatically different patterns, as shown in the enigmatic graph above.

Go to the post to unravel this intriguing mystery!

Sheldon Whitehouse and Ted Lieu Demonstrate Superior Climate Change Activism

Uncategorized, , , , , ,

Subtitle: Politicians School Scientists In How To Do It

Alternative Title: Where were Bernie and Hillary????

You need to know right away that the Lede to this story is buried way the hell down the page.

That’s OK, though, because others are covering this, and the point of my missive is to put the current situation into a somewhat larger context. Ultimately, the point I want to make is this: Even when a problem is mired in deeply entrenched corporate interests, small groups of tenacious heroes can make the world measurably better, and there is such a thing happening right now in the interaction between scientists, one of the world’s largest scientific organizations, one of the world’s largest energy companies, and a handful of elected officials who are doing the right thing.

“Those who make peaceful revolution impossible will make violent revolution inevitable.”

-jfk

A handful of citizens recognize some sort of economic or social injustice involving a corporation. They organize on their own time (they have day jobs) to fight the injustice, and have some success.

A handful of employees of those businesses, or trade organizations that are funded by those businesses, are in charge of public relations and lobbying. They fight the citizens on both fronts, but the citizens were too well organized and the citizen efforts took them by surprise.

The citizens go home at the end of the day, have a party to celebrate their victory, and go back to their day jobs.

The public relations and lobbying employees go home at the end of the day, play with their kids and binge-watch something on Netflix. Then, they also go back to their day jobs. The thing is, their day jobs are to make sure that nothing like this happens again. And, if they can eventually undo the citizens’ group’s success, and maybe even push back a step or two, they get to keep those day jobs.

While the citizens are busy being librarians, sales people, school teachers, and union electricians, the public relations and lobbying employees are busy making sure that the next time a group of citizens comes out of nowhere to effect change, they won’t be able to. It may take a bit of time, but laws will be passed, regulations adjusted, and details of the the inner workings of the corporations and the think tanks and trade organizations that they fund will be updated.

If you’ve ever spent any time in a coffee house in an iffy neighborhood, you know about this problem, because at some point (this may have been more true back a few decades) you were approached by a young man or woman, or even a couple, carrying a clip board and a short stack of tabloid format newspapers. You had a conversation, and you and this person found yourselves in nearly complete agreement on all the issues: education, workers’ rights, health care, military spending, voting rights, women’s rights, social justice, and all of it.

But then the conversation takes an unexpected turn. The person you are talking to points out that every time the people (and you and this person are the people, as are the citizens in the story I related above) manage one step forward, pull off some sort of success, put into effect a small but meaningful incremental change, the corporations and their allies in government change the system to make sure that doesn’t ever happen again. And, for a bonus, they anticipate the next one or two possible incremental changes and make sure they don’t happen either. One step forward, two steps backwards.

Actually, that is not the unexpected turn in the conversation. You actually were already thinking that before the person in the coffee shop mentioned it. Once you think about how things actually work, you realize that incremental change is often the product of temporary and short term efforts by people otherwise involved in other things, but the efforts to stop such change is the product of well trained, richly resourced, and highly effective experts with full time employment with the job description of stopping future incremental change that is not in the interest of the corporation.

Then, the truly unexpected part of the conversation happens. The guy in the coffee shop makes the observation that incremental change will not only always ultimately fail, but it will generally strengthen the establishment and make future change increasingly difficult, so the only way to effect real change is to totally overthrow the government and their corporate overlords.

The only way to make the world work for regular people is a full scale bloody revolution.

The scary part of this conversation is that for a moment it makes total sense to you.

You realize that your new friend in the coffee shop, who by the way has the clip board out and is trying to sell you a subscription to Socialist Worker Monthly, is right. For a moment you imagine yourself wearing all black, with a beret, meeting in the basement of the pet shop down the street, learning how to make bombs or disassemble and reassemble an assault rifle. If you are a young straight unattached male and the guy in the coffee shop is an attractive girl, you may be liable to actually join the revolution for a few months.

But, most likely, that fantasy of overthrowing the government will be soon replaced with memories of some of your history lessons and Wikipedia readings. You’ll realize that these violent revolutions generally take decades, everybody dies, and the scenario, with the establishment cronies managing the opposition, also works at a much larger scale. For example, huge proto-corporate (and Royal) interests manipulated the government and military to maintain the lucrative Triangle Trade in the 18th century, with the American Colonists getting screwed on taxes and expected to be grunts in their colonial wars. The American Revolution put an end to that. But today, Big Energy, Big Ag, Big Pharm and all the rest are capable of pulling the strings of the government marionettes, exploiting the post-Revolutionary free American workers to do their bidding. In the words of Bono, F*ck the revolution.

“Hope is being able to see that there is light despite all of the darkness”

-Desmond Tutu

Sounds pretty bad. Like there is no hope.

Hope does come along now and then, though. Bernie Sanders was hope for a lot of people, who saw his possible presidency as a full on revolution that would totally change the system, and contrasted that with a Clinton presidency, focused on incremental change.

But Sanders would have been one person, in one of the three equally powerful parts of our government, against 535 members of Congress whose careers require funding from the established corporations. And he’s not going to win anyway. So maybe we need to make the best of incremental change.

“The rumors of my death have been greatly exaggerated.”

-The lede of this post

The American Geophysical Union (AGU) is one of the largest scientific organizations in the world. The AGU runs an annual meeting as well as a number of other programs that cost money, and there are many sponsors. One of those sponsors is ExxonMobil. This makes sense, because ExxonMobil, and other petroleum companies, rely on the science practiced by many member of the AGU. Not only does it make sense, but it is right and just that major corporations that benefit from a particular area of science spend money on that science. That expenditure can take many forms, including having well funded research laboratories staffed by excellent scientists within the corporation, supplying grants to scientists working at universities or think tanks, and pitching in with the AGU to help fund their conference.

But, remember those full time employees who were briefly bested by that organized group of citizens? Well, ExxonMobil has that. They have people who are focuses on managing their corporate interests at many levels. And, it recently became apparent that the excellent scientists who worked in the ExxonMobil (the name of the corporation was different then) decades ago had discovered, verified, and documented the important fact that Big Oil’s corporate activities would ultimately lead to catastrophic change in the planet’s environment because of the release of previously trapped carbon, though the burning of oil and gas (and coal as well).

Decisions were made to suppress that research. This is a little like a company making an unsafe car seat keeping their own research indicating this danger under wraps. But it is different from that example because car seats are inherently a safety device. So it is a little more like producing a profitable kind of food that has a serious, but hidden, health effect.

But really, those analogies are weak and, frankly, not needed. What it is like is producing the energy that runs our society and economy and knowing full well that using this form of energy to do so many things will, itself, be a civilization ending enterprise, while at the same time being aware that there are alternatives. But, those alternatives are the business interest of other corporations. So you keep that information under wraps.

The suppression of this important research became known just recently, and a highly specialized set of citizens – scientist associated with the American Geophysical Union – agitated to get the AGU to stop taking funding from ExxonMobil.

The higher ups in the AGU considered this possibility, and eventually decided that “it is not possible for us to determine unequivocally whether ExxonMobil is participating in misinformation about science currently, either directly or indirectly.”

A lot of people saw that as a ridiculous justification for a bad decision. Some might even figure that the previous acts of an earlier incarnation of this giant corporation would be sufficient for the AGU to refuse future sponsorship. But, one could argue that they were bad guys back then but now are good guys, so, well, the AGU needs the money anyway, so why not forgive and forget and get on with it?

Graham Readfearn at Desmog now tells us that Senator Sheldon Whitehouse and House Representative Ted Lieu, have written a letter to the AGU explaining how ExxonMobil has pulled the wool over the AGU’s eyes, causing us to take a step or two backwards with this decision to continue receiving funds.

The letter is to AGU president Margaret Leinen (quoted above) and expresses disappointment with the AGU’s decision.

Here’s the key fact. The AGU has a policy to not accept funding from entities that spend money to promote science disinformation. The AGU had determined that they could not unequivocally know if ExxonMobil was doing so. Part of the reason the AGU determined this is because ExxonMobil told them that they were not funding science misinformation.

The letter from Senator Whitehouse and Representative Lieu states:

EM gave money as recently as 2014 to several organizations that cast doubt on climate change, so we are surprised at AGU’s conclusion. According to EM’s most recent Worldwide Giving and Community Investments report, in 2014, EM funded several organizations that publicly promote misinformation of science, including:

  • American Legislative Exchange Council (ALEC) ($61,500): ALEC has promoted model legislation with a finding that human-induced global warming “may lead to deleterious, neutral, or possibly beneficial climatic changes.”[1]
  • Hoover Institution ($50,000 to its Arctic Security Initiative): Hoover Senior Fellow Terry Anderson, who is not a climate scientist, argued that climate data since 1880 supports a conclusion that it would take as long as 500 years to reach 4 °C of global warming.[2]
  • Manhattan Institute of Policy Research ($100,000 to its Center for Energy Policy): Institute Senior Fellow Robert Bryce stated, “The science is not settled, not by a long shot…. If serious scientists [at the European Organization for Nuclear Research] can question Einstein’s theory of relativity, then there must be room for debate about the workings and complexities of the Earth’s atmosphere. Furthermore, even if we accept that carbon dioxide is bad, it’s not clear exactly what we should do about it.”[3]
  • National Black Chamber of Commerce ($75,000): Chamber President and CEO Harry Alford stated, “[NOAA and NASA] have reported that there has been no global warming detected for the last 18 years. That is over 216 months in a row that there has been no detected global warming…. Scientists, as well as NOAA and NASA, call this state of no warming a ‘Global Pause.’ How long it will last no one predicts. For all we know it may last another 20 years or even forever.”[4]
  • Pacific Legal Foundation ($10,000): A senior attorney at Pacific Legal Foundation attacked EPA’s authority to regulate CO2 because it is a “ubiquitous natural substance essential to life on Earth.”[5]

We have seen no evidence to indicate EM’s behavior has changed since 2014.

You can read the entire letter here.

“There is no comparison between that which is lost by not succeeding and that which is lost by not trying.”

– Francis Bacon

This is obviously a significant development, with respect to the AGU, climate scientists, and all that. But this breaking new story has led me to think about four related but rather extended points.

First, Senator Whitehouse and Representative Lieu are true climate hawks, with records of congressional action on climate change. They are rare birds, too rare. It is not common to be fully active on climate change and have a job in the United States Congress. We need to appreciate their efforts and demand that others join them.

Second, the work done here by these two elected officials should have been done by the AGU. The AGU made weak decision, favoring the financially beneficial status quo and justifying this by not doing the research that was needed. The AGU had its eyes closed, and it is hard to imagine how that could not have been on purpose.

Third, and perhaps tangential to the current issue, but perhaps not: Hillary Clinton and Bernie Sanders didn’t do what Whitehouse and Lieu did. I’m sure it is unfair to accuse them of negligence by not having picked up on this particular story, going after ExxonMobil and correcting the AGU. But think about this for a second. If either one of them had done this – if either’s campaign staff had figured this out and developed a public statement by the candidate that looked a lot like the Whitehouse-Lieu letter – their climate change stock would have gone through the roof, and they would have done something that could actually make a difference.

I don’t fault either of these Democrat’s campaign for failing to do this one specific thing. That would be asking too much. But the fact is that neither candidate has done anything like this during the current primary season, or ever in their previous career. A Sanders supporter might point to Sanders’ prior work on climate change legislation, but it must be understood that Sanders supports a reduction to 80% reliance on non fossil carbon fuel by 2050, which is too little too late. That has been his position for several years, and it is out of date and widely recognized as inadequate, especially following the post-Paris reorientation to a 1.5 degree limit.

A president Donald Trump would probably burn fossil fuel on purpose to piss off the hippies. Either Sanders or Clinton would be a thousand times better. But that stark difference should not lead us to accept mediocracy in our leaders in the issue of climate change.

So the fourth point is this, and it is not about the AGU, but inspired by these recent developments. There are climate hawks in Congress, but only a few, and none of them are running for president. In choosing between Sanders and Clinton to determine which one might have the best climate change policy, it is easy to decide that one of them (or even both of them) have a good policy. But the truth is, neither candidate is where we need them to be on climate change. Both candidates have strong points, and different strong points, backed up by detailed policy positions and enhanced by histories of legislation or activism of one sort or another. And when we list those strong points, we do not find climate change policy among them.

I reject all efforts to compare Sanders and Clinton on climate change, at this point in the primary process, for two reasons.

First, Clinton will be the nominee, based on math. So the comparison is moot. Second, the Democratic Party did not put forth a sustained climate change savvy candidate for us to choose. So, we can’t like what we have now, we can not be satisfied. We have to hold the candidate’s feet to the fire, push, cajole, insist, vigorously engage.

The scientists who asked, in a letter, the AGU to cut ties with ExxonMobil tried to take a step foreword. The AGU caused us to take a step backwards. Let’s help Whitehouse and Lieu push us two steps forward, one against ExoonMobile (by helping the AGU to make the right decision) and one in the current presidential race, by demanding better of our candidates.

Ft McMurray Fire and Climate Change: Michael Mann Comments

Uncategorized, , , , , , ,

This is a segment of The Big Picture with Thom Hartmann, in which climate scientist Professor Michael Mann provides important perspective on the link between climate change and other disasters such as tornadoes. (See also: The Meaning of the Fort McMurray Fire).

Michael Mann is the author of The Hockey Stick and the Climate Wars: Dispatches from the Front Lines, and Dire Predictions, 2nd Edition: Understanding Climate Change (a visually rich summary of the most recent IPCC report) as well as the forthcoming book combining climate science and political cartooning, The Madhouse Effect: How Climate Change Denial is Driving Us Crazy!.

For more information on the science showing the link between climate change and weather patterns, discussed in the video by Professor Mann, see these items:

<li><a href="http://scienceblogs.com/gregladen/2015/03/12/new-study-on-how-global-warming-changes-the-weather/">New Study On How Global Warming Changes The Weather</a></li>
<li><a href="http://scienceblogs.com/gregladen/2014/08/14/more-research-linking-global-warming-to-bad-weather-events/">More Research Linking Global Warming To Bad Weather Events</a></li>
<li><a href="http://scienceblogs.com/gregladen/2013/09/28/global-warming-and-extreme-weather-climate-agw/">Global Warming and Extreme Weather – #climate #agw</a></li>
<li><a href="http://scienceblogs.com/gregladen/2013/06/04/linking-weather-extremes-to-global-warming/">Linking Weather Extremes to Global Warming</a></li>

See also:

<li><a href="http://scienceblogs.com/gregladen/2016/04/20/this-is-the-worst-coral-bleaching-episode-in-australias-history/">“This is the worst coral bleaching episode in Australia’s history”</a></li>

The Madhouse Effect: How Climate Change Denial is Driving Us Crazy!

Uncategorized, , , , , , , ,

The Madhouse Effect: How Climate Change Denial Is Threatening Our Planet, Destroying Our Politics, and Driving Us Crazy, by climate scientist Michael Mann and cartoonist Tom Toles is now available for pre-order. I’ve not gotten my review copy of it yet, but it looks fantastic.

From the publisher:

The award winning climate scientist Michael E. Mann and the Pulitzer Prize-winning political cartoonist Tom Toles have fought at the frontlines of climate denialism for most of their careers. They have witnessed the manipulation of the media by business and political interests and the unconscionable play to partisanship on issues that affect the well-being of millions. The lessons they have learned have been invaluable, inspiring this brilliant, colorful escape hatch from the madhouse of the climate wars.

Through satire, “The Madhouse Effect” portrays the intellectual pretzels into which denialists must twist logic to explain away the clear evidence that man-made activity has changed our climate. Toles’s cartoons collapse counter-scientific strategies into their biased components, helping readers see how to best strike at these fallacies. Mann’s expert skills at science communication aim to restore sanity to a debate that continues to rage against widely acknowledged scientific consensus. The synergy of these two commonsense crusaders enlivens the gloom and doom of so many climate-themed books–and may even convert a few of the faithful to the right side of science.

Climate Or Bust: Sanders and Clinton Should Step Up Now

Climate Change, Uncategorized, , , , , ,

This is a guest posts by Claire Cohen Cortright.

Claire Cohen Cortright is a mother, climate activist, and biology teacher living in upstate New York. She

is an active member of Citizens Climate Lobby and moderator at Global Warming Fact of the Day.

It is time, now, for climate activists to get vocal.

As it becomes more clear that Hillary Clinton will be the Democratic Party’s nominee for President, there is increasing talk about the importance of unifying the party. Negotiations are on the horizon … for Vice President and for the Party’s policy platforms.

Now, we must be sure climate change and carbon cutting policy are part of those negotiations.

Consider, for a moment, as Bernie Sanders begins to make demands in exchange for his support, what he will insist upon. What are the key policies will he insist be incorporated into the Democratic Party platform?

His campaign’s latest email provides a likely answer to this question:

“What remains in front of us is a very narrow path to the nomination. In the weeks to come we will be competing in a series of states that are very favorable to us – including California. Just like after March 15 – when we won 8 of the next 9 contests – we are building tremendous momentum going into the convention. That is the reality of where we are right now, and why we are going to fight for every delegate and every vote. It is why I am going to continue to speak to voters in every state about the very important issues facing our country. Our country cannot afford to stop fighting for a $15 minimum wage, to overturn Citizens United, or to get universal health care for every man, woman, and child in America.” (Emphasis mine).

Notice what is missing?

The single most important issue of our day. The single biggest threat to national security.

Climate change.

Climate activists have been insisting that climate change be made the top level priority for all campaigns and all elected officials. It is possible that this activism has failed to varying degrees with respect to both the Sanders and Clinton campaigns. That means it comes down to us to insist that meaningful carbon cuts are at the top of the platform.

Hillary Clinton critics are right. Hillary has wrongly called gas a bridge fuel. She absolutely needs to be pushed to make it her goal, and that of the Democratic Party, to END the use of gas and all other fossil fuels. She has good solid plans to regulate fracking. Those policies will drive up the cost of gas and therefore send price signals that, in the absence of a price on carbon, will drive us toward other sources of energy. But it is essential that we have the stated goal of ending gas. That will set the stage for the essential conversations about how we will replace that gas without turning off the lights and heat. Efficiency, lifestyle changes, renewables, and, yes, nuclear.

Bernie Sanders’ stated policy is allow nuclear plant licenses to lapse. If nuclear plants close now, they are likely to be replaced with gas. He has said that he isn’t closing the plants now, just allowing for them to close by attrition. However, the reality is that nuclear plants are already closing now, before their licenses lapse, because electricity is so cheap that regular maintenance is economically unfeasible. Part of that calculation is lifetime return. If you know you won’t be relicensed in 2025, it is all the more reason not to do 2017’s maintenance and instead close down. And once a nuclear plant is mothballed, it’s done. You can’t just refurbish and turn it back on, like you can with gas and coal. Unfortunately, there is little political will to take on the nuclear issue within the party at this point. Maybe that means we can simply accept Hillary’s approach to leave nuclear alone. Perhaps her political calculation on nuclear was simply on target.

Perhaps the one thing all climate activists can agree to demand in these negotiations is a carbon tax. Hillary Clinton has had, for many months, a vague, buried reference to carbon markets in her policy platform.* People have made little mention of it, simply saying she doesn’t support carbon taxes. Why not highlight that she seems to support carbon pricing, insist that she become more vocal about it, and push her to explain why she is supporting cap and trade over taxes? As that conversation unfolds, she will be forced to address the distinctions, and, at the same time, the electorate will become more knowledgeable about carbon pricing. At the end of the day, the party platform may end up with a clear carbon price plan.

Whatever climate policies end up in the Democratic Party Platform, it is clear that climate activists must put aside the horse race between Clinton and Sanders and remember that neither of them go far enough. Neither is prepared to get to zero emissions by 2050. Neither sees climate as the single most important issue to address.

It is time for climate voters and climate activists to demand that the Democratic Party serve up more than fiery rhetoric from Sanders and more than visionless bridge fuels from Clinton.

It is time to demand the best from each of them and ensure they don’t simply offer up their worst on climate.

*Here is her vague buried reference to clean energy markets:

“Clean Power Markets: Build on the momentum created by the Clean Power Plan, which sets the first national limits on carbon pollution from the energy sector, and regional emissions trading schemes in Canada, Mexico, and the United States to drive low carbon power generation across the continent, modernize our interconnected electrical grid, and ensure that national carbon policies take advantage of integrated markets.” source

“This is the worst coral bleaching episode in Australia’s history”

Uncategorized, , , , , , ,

Corals are ocean-dwelling invertebrates in the same phylum as jellyfish. Corals are tiny and create an exoskeleton that is fixed to something hard, like the remains of previously existing corals. So these organisms build up a geological stratum, a reef, beneath the surface of the sea, often close enough that parts of the reef are exposed at the lowest water level. The coral reef system is the substrate for one of the Earth’s major ecological zones.

Corals are symbiotic with a single celled dinoflagellate, a kind of algae that combines available nutrients such as ammonia and the photosynthetic process using sunlight to grow, maintain, and reproduce. These algae provide the coral with nutrients, and the waste products produced by the corals are the nutrients used by the dinoflagellates. Depending on the species, corals may also trap tiny organisms and eat them. There are many species of both symbionts, there are multiple possible combinations of symbionts that work, and it is all very complex.

Under certain conditions, the corals are unable to provide the symbiont algae with nutrients, so the latter either die or simply abandon the relationship. Reduction in nutrients provided by the dinoflagellates further reduces the coral’s bioactivity, worsening the situation, in a kind of downward spiral.

The algae symbionts provide the coral structure with its famous color, so when they abandon the relationship, the primary color of the coral structure is white, so the process is referred to as bleaching.

There are a lot of things that can cause bleaching, including disease, physical damage by storms, changes in water chemistry, and warming of the waters. Sea temperatures are elevated because of surface warming caused by human released greenhouse gas pollution, so corals around the tropics are generally more susceptible to bleaching than they have been in known history, and many mass bleaching events have been observed over the last 20 years or so. During El Niño years, ocean temperatures in certain regions can go even higher, so El Niño years are typically associated with numerous mass bleaching events. This year, we have extremely elevated ocean temperatures caused by anthropogenic global warming, in combination with an exceptionally strong El Niño, and this has caused the Great Barrier Reef, the world’s largest reef ecosystem, to crash.

According to the University of Queensland Global Change Institute Director Ove Hoeghguldberg, “From the tip of Cape York to the Whitsundays, the Great Barrier Reef in the east to the Kimberley’s in the west and Sydney Harbour in the south, Australia’s corals are bleaching like never before. This is the worst coral bleaching episode in Australia’s history, with reports of coral dying in places that we thought would be protected from rising temperatures.”

Coral scientist Tyrone Ridgeway adds, “Previously, scientists thought the reefs off Western Australian could withstand bleaching and that southern waters around Sydney would be too cool for bleaching — this year has shown that is not the case. It will already take several decades for coral reefs to recover from this bleaching event.”

As noted, coral reefs form the basis for a major ecosystem, but also, for a major economy. There are lots of places in the world that people visit almost entirely for the corals, or some natural feature related to the corals. In Australia, some 69,000 people are employed in a five billion dollar industry of coral ecotourism and aquaculture.

Reefs can recover. Somewhere out there on the reef there are a few surviving corals, and a few surviving dinoflagellates. If conditions return to normal, they may start to recolonize the reef surface. However, it is also possible that the coral ecosystem can be replaced with an algae mat ecosystem across large areas. Living coral reefs maintain their relative position in relation to the sea surface, and thus provide barrier effects and control the geomorphology of a huge ecosystem. An algae mat ecosystem would presumably erode more than grow (except in very protected areas), and between that and sea level rise, the barrier effect would be significantly reduced.

Also, it takes months to years for recovery to occur, and the worse the bleaching the longer it takes. We are probably entering an era where heat stress bleaching will become much more common, and more severe when it does occur. At the same time, severe and physically large tropical storms are becoming much more common in the Pacific, so the chance of a second hit from this effect during recovery is increased. In other words, over the next few decades, a major reef like the Great Barrier Reef may become bleached more often than not over much of its area. Eventually, as sea temperatures continue to warm, it may simply become impossible to maintain such reefs.

There is some hope in that dinoflagellates that can withstand warmer conditions could become predominant, or even evolve. Perhaps in a few centuries from now, reefs will adjust to new conditions. On the other hand, climate change results in higher variability of temperature conditions, not just an increase, which would make such an adaptation difficult. Keep in mind that during recent history of life (over a few hundred million years or so) there have always been reefs, but not always made and maintained by corals. The organisms that produce this important ecosystem have, in the past, gone extinct and been replaced by entirely different systems, several times. That replacement was unlikely to have been a neat and efficient process.

More information here.

New climate study is frenemy of climate science driven policy

Uncategorized, , , , ,

There is a new study out in Nature that is liable to be misinterpreted, or that may be flawed in a way that lends itself to misuse, in the context of climate science driven policy.

The study is “Northern Hemisphere hydroclimate variability over the past twelve centuries” by Fredrik Charpentier Ljungqvist, Paul J. Krusic, Hanna S. Sundqvist, Eduardo Zorita, Gudrun Brattström & David Frank

I’ll make just a few comments here, but mainly, I want to point you to comments by climate scientist Michael Mann (author of The Hockey Stick and the Climate Wars: Dispatches from the Front Lines and Dire Predictions, 2nd Edition: Understanding Climate Change).

The main question related to policy is this. Do warmer conditions such as we are experiencing now as a result of human greenhouse gas pollution change the hydrology of the planet? The answer, based on various research projects, is yes. Two main things seem to pertain. First, there is more moisture in the air owing to the air being warmer and sea surface temperatures being higher. More moisture holding capacity and more evaporation (movement of water into the air as vapor) result in this effect. At the same time, changes in weather patterns can clump a good amount of this moisture up, so even a modest amount of increase in atmospheric moisture can (and does) result in major precipitation events, causing flooding and other untoward events. This clumping can also serve to deprive some areas of moisture for extended periods of time, and major droughts such as in the Middle East and California are attributed at least in part to this effect.

The study seems to show that this is not likely. The study looks at paleo data over thousands of years, testing and extending a model to apply to present and future climates. The result seems to show that the more extreme changes in hydrology, either wetter or dryer, are not likely. However, Mann makes the point that the kind of data used in this study, such as tree rings, do not reliably show extreme events. In other words, extreme events in the past likely happened without leaving much of a signal.

Mann’s comments are in a facebook post partly reproduced here:

…The study represents a laudable effort to document past changes in extreme rainfall and drought using paleoclimate proxy data, but there are some shortcoming with the study, and especially with the way it is being billed by some of the study’s authors and certain organizations.

A press release from the international paleoclimate organization ?#?PAGES? is accompanied by the rather bold headline “Climate models overestimate twentieth century wet and dry climate extremes”. The lead author Fredrik Ljungqvist is quoted in the press release stating that the discrepancy between the smaller hydroclimatic variations shown by their paleoclimate proxy reconstruction and the greater variations shown by climate models imply that “Climate models strongly overestimate the intensification of wet and dry extremes in the twentieth century”.

Does this study in fact meet the burden of establishing that models are overestimating extremes in rainfall and drought?

Almost certainly *not*.

The discrepancy could arise, of course, from the opposite problem: that the paleoclimate proxy data are *underestimating* hydroclimatic extremes. In my view, that is a far more likely explanation.

Our own extensive work analyzing paleoclimate proxy data has shown has demonstrated they are not well suited for reconstructing past climate *extremes*. Tree rings and many other chemical and biological climate proxy records, by their nature, tend not to record very large short-term fluctuations, and for this reason they are likely to show muted extremes, i.e. less extreme variation than actually exists in the climate record. We published several articles demonstrating this problem over the past several years:

  • Schurer, A., Hegerl, G., Mann, M.E., Tett, S.F.B., Separating forced from chaotic climate variability over the past millennium, J. Climate, 26, 6954-6973, 2013.
  • Mann, M.E., Rutherford, S., Schurer, A., Tett, S.F.B.,Fuentes, J.D., Discrepancies between the modeled and proxy-reconstructed response to volcanic forcing over the past millennium: Implications and possible mechanisms, J. Geophys. Res. 118, 7617-7627, doi:10.1002/jgrd.50609, 2013.
  • Mann, M.E., Fuentes, J.D., Rutherford, S., Underestimation of Volcanic Cooling in Tree-Ring Based Reconstructions of Hemispheric Temperatures, Nature Geoscience, 5, 202-205, 2012.

    • (all available here)

    So, in conclusion, it would be rather dangerous to extrapolate from this one potentially flawed new paleoclimate study any sweeping conclusions about climate models and human-caused climate change. Such over-interpretations of paleoclimate data poorly serve the critical public discourse over the impacts of climate change, and can in fact do harm to the paleoclimate discipline by publicizing bold but unsubstantiated claims that are very likely to be refuted by further work.

    People finally concerned about climate change

    Uncategorized, , , , , , ,

    Though not enough. And for the wrong reasons. But this is still good news.

    Somewhere around 1990, but you could justify an earlier date if you like, science knew enough about global warming, the increase in the planet’s surface temperatures caused by human release of greenhouse gas pollution and other human effects, to have initiated meaningful action to shift our energy supply away from fossil fuels. We didn’t know exactly what would happen, but we knew stuff would happen. How long has it taken for this science to turn into effective policy to address global warming? We don’t know, because, while some things are happening now, not enough. We are not doing what we need to be doing decades after we should have started doing it.

    The main reason we have avoided effective action is because of bought and paid for denial of the science supported mainly by the industries that stand to lose the most if we eliminated our reliance on fossil fuels. These industries could have done something very different. They could have started to develop and deploy clean energy solutions, and dissolve their fossil fuel based assets. But they didn’t. So we are in a bad situation right now.

    Meanwhile this systematic and effective denial of science has kept public opinion confused, with many people failing to accept the reality of global warming. But now, we are seeing a major shift away from denial and towards accepting, if not fully understanding, the science, and getting on board with a shift in policy.

    That is a good thing, though it is slightly annoying that a) recent lackluster opinion has resulted from the incorrect perception that an expectable slowdown in warming means global warming isn’t real (it doesn’t actually mean that) followed by b) an uptick in global warming’s effects caused by short term exacerbation from the current, now winding down, El Nino.

    The last time there was a big uptick in US public concern about global warming was in association with the most recent major El Nino, and now, with this new major El Nino, concern has risen again, according to Gallup.

    Hunter Cutting has a piece on Medium exploring this in more detail. He asks if the current uptick in concern is a tipping point in public opinion.

    He notes,

    For the past year there have been hints of a significant shift in the U.S. political landscape on the question of climate change. Now, new polling numbers just out from Gallup confirm not just a shift, but a seismic shift, in public opinion on the question. The shift is so dramatic that we may have passed a key tipping point in the politics of climate change.

    But he further notes,

    The political landscape must change still further before federal action can take the next big steps forward on climate change. Despite increasing agreement that climate change is a problem, most still don’t see the problem as a pressing concern calling for immediate action. But U.S. politics are notoriously non-linear. Political change often happens fast once the ball gets rolling.

    If a Republican is elected to the White House, and both houses of Congress stay Republican, expect anywhere from a half decade to a decade of delay in acting meaningfully on clean energy policy. Yes, the markets are already heading that way, but don’t underestimate the ability of a nefarious petroleum fueled anti-change government to slow that down or even reverse it. This is why this November is the most important election in American, and global, history. Please don’t blow it.

    Climate Change: A Wicked Problem

    Uncategorized, , , , ,

    Climate Change: A Wicked Problem: Complexity and Uncertainty at the Intersection of Science, Economics, Politics, and Human Behavior, by Frank Incropera, is a textbook suitable for use in advanced high school or college classes, but also an excellent primer on the topic for anyone interested in it. Incropera spares little details in describing how the Earth’s climate system works, and how human generated greenhouse gases, and other effects, change the energy balance of the planet to produce the phenomenon we call “global warming,” and other effects.

    Incropera addresses the panoply of causes of warming, feedback systems, and effects, as well as the range of strategies proposed to address climate change. More than many other books covering this large and complex topic, Incropera addresses energy production. He also looks at societal, cultural, religious, ethical, and other factors that come into play when we try to figure out what to do about this “wicked problem.” This book makes clear that this is not a simple problem, but a complex one because of the vast and variable scales of time and space involved.
    Screen Shot 2016-03-07 at 7.56.55 AM
    The book is very thorough and, as an academic text, well documented, rich in detail (with numerous appendices) and well indexed. I have a sense that there was a fairly long time between the production of visuals and the publication of the book, as many of the graphics don’t bring us up to the most recent year for which there are data, which actually obviates the use of many of the otherwise excellent figures. But, I suppose, one could not know, say, a year and a half ago that we were going to start breaking surface temperature records almost every month.

    There have been a few textbook-style academic books on climate change produced over the years. Climate Change: A Wicked Problem: Complexity and Uncertainty at the Intersection of Science, Economics, Politics, and Human Behavior has the nearly unique feature that it was simultaneously produced as an affordable paper back, so you don’t have to wait for it to get old and remaindered to pick up a copy!

    Table of Contents

    <li>Foreword Tony Earley</li>

<li>Foreword Bud Peterson</li>

<li>Foreword Arun Majumdar</li>

<li>1. Energy, economics, and climate change</li>
  • 2. The earth’s climate system
  • 3. Greenhouse gases
  • 4. Global warming
  • 5. Consequences of global warming
  • 6. Mitigation, adaptation, and geoengineering
  • 7. Public policy options
  • 8. The politics of global warming: a history lesson and future prospects
  • 9. Dissenting opinions: the great hoax
  • 10. The ethics of climate change
  • 11. A way forward
  • References
  • Index.

    • Followed by appendices on unit conversions, fossil fuels, sources of methane, time scales, and coal-fired plants; And notes.

    Are we witnessing an Arctic Sea meltdown, right now?

    Uncategorized, , , , , ,

    The Arctic Sea freezes over. The Arctic Sea melts. This happens every year. The average date for the maximum extent of Arctic Sea ice, based on a period of 1981-2010, is March 12. The minimum extent is reached, on average, about September 15h.

    Every year for the last several years, the minimum ice has been much lower than average in extent, and many years in a row have seen record minima. This is considered to be the result of global surface warming caused by human release of greenhouse gas pollution.

    It is said that we can’t use the maximum ice cover to predict the minimum ice cover very accurately, because a lot of things can happen to affect the total ice cover during those many months of melting. However, the maximum ice amount for, say, 1979-1988 (the first ten years for which we have really good data on this) was high compared to the last ten year period, and correspondingly, the minimum extent was greater for that first ten year period than the most recent ten years, so there is a correlation. Still, the date of the maximum extent has tended to not move around much, and the same is true for the date of the minimum extent.

    Bt maybe not this year. This year’s maximum Arctic Sea ice extent seems to have flatlined at a record low value, as shown in the graph above, from here. The current sea ice extent is that red line all by itself down near the bottom.

    It may well be the case that the sea ice will start to re-freeze, and this line will go up again over the next two weeks or so, and max out near the historical average. The next week or so should be below freezing across much of the Arctic Sea, but there is a warm intrusion near Greenland and Europe, with above freezing air, expected to persist for that entire time. Overall, warm air and ice-breaking-up storms have invaded the Arctic repeatedly this winter. The sea ice extent may recover over the next several days, but I get the impression that most experts are quietly thinking it won’t.

    This is not terribly surprising, given that the Earth’s surface temperatures are increasing, and sea ice is decreasing. This year, a El Ninño is adding fuel to the fire, as it were, and making these conditions even more extreme.

    A concerning possible outcome is this: The Arctic Sea ice helps cool the planet by reflecting away sunlight. It is a reasonable assumption that during summers with much less ice, there is much less cooling. This can have impacts on the longer-lived fast ice* that is also melting in the arctic, and on nearby glaciers in greenland, and the planet overall. This is what is known as a “positive feedback” which is a somewhat misleading term, because this is not an especially “positive” event.

    *CORRECTION: My friend and colleague Tenney Naumer, who watches both the weather and the Arctic very closely, contacted me to let me know that the “fast ice” is long gone. She told me, “In 2012, the ice in the channel between Ellesmere and Axel Heiberg Island (to the south of Ellesmere) melted out — that is the place where the ice had existed for more than 10,000 years. The Ward Hunt Ice Shelf broke off in 2002. The Ayles Ice Shelf broke off in 2005. In 2007, I watched (here) the ice break away from most of the Arctic side of the archipelago, and it has been all downhill since. It’s all gone now.”

    What is the “pause” in global warming?

    Uncategorized, , , , , ,

    A new paper (commentary) on the so-called “pause in global warming” puts it all together.

    First let’s establish this as a starting point. When climate science contrarians refer to a “pause” or “hiatus” in global warming, they usually mean that the process of warming of the Earth’s surface caused by the human release of greenhouse gas is not a thing. They are usually implying, or overtly claiming, that the link between CO2 and other greenhouse gas pollutants and surface warming was never there to begin with, and previous warming, warming before “the pause,” was natural variation. Many even go so far as to claim that the Earth’s surface temperature will go down to levels seen decades ago.

    “The Pause” is not, in their minds, a slowdown in the rate of warming. It is a disconnect, either there all along or produced somehow recently, between the physics of the greenhouse effect and reality.

    Also, the evidence adduced for this “pause” is often bogus. Sometimes badly calibrated satellite data is used to show a flat Earth surface. Er, flat Earth surface temperature. Sometimes a line is drawn from an unusually warm, even under conditions of global warming, El Niño year, to later years, lately excluding record breaking recent warm years, in order to make the line flatter. So, that part of the denier pause is a different kind of lie. See this post and this post for recent research on this issue.

    Having said all that, there have been frequent slowdowns and speed-ups in the rate of the planet’s surface warming throughout the entire instrumental record. (Even though the instrumental record begins in 1850 or 1880, depending on which data set you use, greenhouse gas pollution started before that, so some greenhouse warming has been happening all along).

    Prior some date, like 1970 perhaps, the up and down variations in surface temperature has been a combination of natural variation and human caused variation, with both being strong factors. The human caused variation includes particulate pollution (from burning coal, mainly) which pushes the temperature down, and greenhouse gas release and its associated effects, which push the temperature up.

    For the last third or so of the 20th century, through the present, while both natural and human-caused effects matter, the role of human effects has increased to be the dominant force in the overall trend. The natural variations continue to contribute to the shape of the curve, but this contribution is attenuated by the increased abundance of human generated greenhouse gas.

    For the last few years, we have seen several research projects that look at the “pause.” Many of these projects helped to explain the slowdown by showing that it wasn’t really as much of a slowdown as previously thought. For example, some research showed that the surface warming in recent decades has been under-measured because the Arctic (and probably the interior of Africa) were getting warmer faster, compared to other regions, and those areas were under-sampled by the usual data sets. Also, heat has been moving in and out of the ocean all along, and that has had an effect on the surface temperaturews.

    But even after accounting for all of these effects, there is still a slowdown.

    John C. Fyfe, Gerald A. Meehl, Matthew H. England, Michael E. Mann, Benjamin D. Santer, Gregory M. Flato, Ed Hawkins, Nathan P. Gillett, Shang-Ping Xie, Yu Kosaka and Neil C. Swart have just published a commentary in Nature Climate Change called “Making sense of the early-2000s warming slowdown” that looks at what caused this partial flattening out of the upward trend in global surface temperatures.

    Part of this investigation compares the earlier part of the 20th century, when there was a much more significant slowdown in warming, with the more recent slowdown. Fyfe et al note that there are two major contributors to variation in surface temperature aside from greenhouse gases. One is the abundance of aerosols, such as industrial pollution (more of a factor during the earlier hiatus) and the output of volcanoes (such as the 1991 eruption of Mount Pinatubo). The other is multi-decade scale variation in the interaction between the oceans and the atmosphere. The following figure compares the two periods of reduced rate of warming.

    Screen Shot 2016-02-23 at 1.22.39 PM

    As noted in the caption, the two periods are representations of how far off from expected (based on simple greenhouse warming) each period is. It happens that these two periods of slowdown in rate of warming are associated with the negative phase of a major ocean-atmosphere interaction, during which the ocean was eating up some of the extra heat, removing it from the atmosphere. The intervening period of increased rate of warming (from the mid 1970s to about 2000) is associated with a period when this system was in positive phase, putting heat out into the atmosphere. As I’ve noted before, the ocean, which takes up most of the global warming caused heat, is the dog, and the atmosphere is the tail. This is a graph of a dog wagging its tail.

    It is not clear when the multi-decade scale ocean-atmosphere interactions will shift to a positive phase. If you look at just the raw numbers, it seems like this may have started a few years ago (around late 2013) but the index for this phenomenon varies enough (goes positive and negative and back over shorter time periods, briefly) that this is not certain. More recently, we have an El Nino causing the belching of heat form the ocean to the air, heating up the surface. This may or may not be related to the multi-decade pattern. Having said all that, we may be concerned that over the next ten years or so, starting about now, we will be in a positive phase during which the rate of warming will be accelerated. This may not be the case. Or it might be the case. No one is actually betting on this yet.