PASADENA, Calif. – An international team of experts supported by NASA and the European Space Agency (ESA) has combined data from multiple satellites and aircraft to produce the most comprehensive and accurate assessment to date of ice sheet losses in Greenland and Antarctica and their contributions to sea level rise.
In a landmark study published Thursday in the journal Science, 47 researchers from 26 laboratories report the combined rate of melting for the ice sheets covering Greenland and Antarctica has increased during the last 20 years. Together, these ice sheets are losing more than three times as much ice each year (equivalent to sea level rise of 0.04 inches or 0.95 millimeters) as they were in the 1990s (equivalent to 0.01 inches or 0.27 millimeters). About two-thirds of the loss is coming from Greenland, with the rest from Antarctica.
From the abstract of the paper:
We combined an ensemble of satellite altimetry, interferometry, and gravimetry data sets using common geographical regions, time intervals, and models of surface mass balance and glacial isostatic adjustment to estimate the mass balance of Earth’s polar ice sheets. We find that there is good agreement between different satellite methods—especially in Greenland and West Antarctica—and that combining satellite data sets leads to greater certainty. Between 1992 and 2011, the ice sheets of Greenland, East Antarctica, West Antarctica, and the Antarctic Peninsula changed in mass by –142 ± 49, +14 ± 43, –65 ± 26, and –20 ± 14 gigatonnes year?1, respectively. Since 1992, the polar ice sheets have contributed, on average, 0.59 ± 0.20 millimeter year?1 to the rate of global sea-level rise.
The melting since about 1992 to the present has contributed to about 0.44 inches of sea level rise (about a fifth of the sea level rise over that period, and there was sea level rise prior to 1992 as well). The main outcome of this study is to clean up the predictions from previous models with much better data and to narrow down the best predictions for future melting. Also, the pace of ice loss now is greater than it was at the beginning of the study period, 20 years ago. Greenland is losing ice about 500% faster now than it was in the early 1990s, while Antarctica is losing ice at about the same rate now as it was then.
Shepherd, A., Ivins, E., A, G., Barletta, V., Bentley, M., Bettadpur, S., Briggs, K., Bromwich, D., Forsberg, R., Galin, N., Horwath, M., Jacobs, S., Joughin, I., King, M., Lenaerts, J., Li, J., Ligtenberg, S., Luckman, A., Luthcke, S., McMillan, M., Meister, R., Milne, G., Mouginot, J., Muir, A., Nicolas, J., Paden, J., Payne, A., Pritchard, H., Rignot, E., Rott, H., Sorensen, L., Scambos, T., Scheuchl, B., Schrama, E., Smith, B., Sundal, A., van Angelen, J., van de Berg, W., van den Broeke, M., Vaughan, D., Velicogna, I., Wahr, J., Whitehouse, P., Wingham, D., Yi, D., Young, D., & Zwally, H. (2012). A Reconciled Estimate of Ice-Sheet Mass Balance Science, 338 (6111), 1183-1189 DOI: 10.1126/science.1228102
Photo of icebergs in Disko Bay, Greenland from NASA
Despite the fact that the word “Dinosaurs” occurs in the title, this book is only partly about dinosaurs. In fact, I would say it is mostly about mammals, insofar as the critters go. And that’s good because Donald Prothero is probably the world’s leading expert on Fossil Mammals. The dinosaur part is major and interesting, though. One of the mysteries Don addresses is the presence of Dinosaurs in the region of the earth that is dark for 6 months out of the year and generally frozen. Indeed, the “greenhouse effect” was very much stronger (in that there were more greenhouse gasses) in those days than today. All that atmospheric Carbon (in the form of CO2) was eventually to be trapped in the lithosphere, which helped cause the planet to cool to the levels that were around when we, as a species (genus, really) evolved. The world in which everything alive today evolved in is a world with a few hundred parts per million of CO2 in the atmosphere, the world of the “Dino Greenhouse” had much more CO2, and we are quickly heading back to the Dinosaur era level, which is going to really mess us up.
Greenhouse of the Dinosaurs: Evolution, Extinction, and the Future of Our Planet addresses questions of “Yeah, so, it was hot then and everything was fine, so Global Warming is not important.” Don also regales the reader with stories about doing palaeontology, about controversies in the field, and that sort of thing. And, he brings us past the K-T boundary, to the “Cainozoic” (age of “Cain) during which the earth cooled, and mammals took over to be the dominant large visible above ground life form. (Yes, yes, I know, bacteria are the dominant life form, yadda yadda… just don’t look for any murals of bacteria interacting on the wall of the Yale Peabody Musuem any time soon.)
Climate Denial Crock of the Week gives us this new video. Details here.
We are not yet where we need to be with this “when did you stop beating your wife” question sometimes in the form of:
“Can you REALLY attribute ANY storm to Global Warming, really? No? Then is global warming really real? Really?”)
Next time someone says something like that to you, consider answering the question with a question:
“Which major storm of the last two decades or so did not include any of the extra climatic energy provided to this planet by the release of fossil Carbon and other greenhouse gasses into the atmosphere by human activities? WHICH ONES, DAMMIT!?!??”
Imagine the following scenario. Two guys are walking down the street, in different cities. Guy A has two PhDs, one in quantum physics with a focus on dimensionality dynamics, the other in astrophysics with a focus on relativistic aspects of gravity and black holes. She has published dozens of peer reviewed papers on both topics and is a brilliant mathematician. Guy B never took a physics class but yesterday he finished reading large parts of The Elegant Universe. Suddenly, at the same moment, they each have an idea (they do not have the same idea … they have different ideas) about how to unify quantum level and cosmic level dynamics. Continue reading Empowering the individual does not equal ensmartening the individual→
This is temperature increasing on the earth over a century or so. Notice that there is what looks like a warming around 1940 on top of an otherwise mostly warming trend, followed by a bunch more warming.
The Fourth Assessment Report of the IPCC, in 2007, referring to data that ran up to 2005 inclusively, said the following:
Most of the observed increase in global average temperatures since the mid-twentieth century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations.
Later, in a congressional hearing, Patrick Michaels, a climate science denialist (one of the meteorologists famous for his rejection of the data and science demonstrating a human induced warming trend) said to a congressional committee, of the statement by the IPCC:
… greenhouse-related warming is clearly below the mean of relevant forecasts by IPCC … the Finding of Endangerment from greenhouse gases by the Environmental Protection Agency is based on a very dubious and
critical assumption.
A probabilistic quanti?cation of the anthropogenic component of twentieth century global warming examines both claims and concludes that Michaels is wrong. From the abstract:
This paper examines in detail the statement in the 2007 IPCC Fourth Assessment Report that “Most of the observed increase in global average temperatures since the mid-twentieth century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations.” We use a quantitative probabilistic analysis to evaluate this IPCC statement, and discuss the value of the statement in the policy context. For forcing by greenhouse gases (GHGs) only, we show that there is a greater than 90% probability that the expected warming over 1950–2005 is larger than the total amount (not just ‘‘most’’) of the observed warming. This is because, following current best estimates, negative aerosol forcing has substantially offset the GHG-induced warming. We also consider the expected warming from all anthropogenic forcings using the same probabilistic framework. This requires a re-assessment of the range of possible values for aerosol forcing. We provide evidence that the IPCC estimate for the upper bound of indirect aerosol forcing is almost certainly too high. Our results show that the expected warming due to all human in?uences since 1950 (including aerosol effects) is very similar to the observed warming. Including the effects of natural external forcing factors has a relatively small impact on our 1950–2005 results, but improves the correspondence between model and observations over 1900–2005. Over the longer period, however, externally forced changes are insuf?cient to explain the early twentieth century warming. We suggest that changes in the formation rate of North Atlantic Deep Water may have been a signi?cant contributing factor.
Not only is the IPCC assessment correct according to this new paper, but it is a bit of an understatement.
So much for that little bit of climate science denialism.
Wigley, T., & Santer, B. (2012). A probabilistic quantification of the anthropogenic component of twentieth century global warming Climate Dynamics DOI: 10.1007/s00382-012-1585-8
One of the reasons that we have not, as a species, as a group of nations, dealt effectively with Anthropogenic Global Warming is the effectiveness of climate science denialism. There are denialists in Congress, on the Internet, and everywhere. They have not succeeded in making a valid scientific argument regarding Global Warming, but they have kept the rhetoric in the foreground, which has allowed interests protecting Big Oil to keep the hapless Main Stream Media focused on a false balance between scientific consensus and unreasonable doubt. As a result, the last decade or so has been a wash when it comes to international action on Carbon emissions and other ameliorating action. As a result, the idea that we could keep global temperature rise from going past the 2 degree C mark. Now, it is increasingly understood that we are heading for much warmer conditions, and this has the World Bank worried.
The World Bank just commissioned an analysis by scientists at the Potsdam Institute looking at the consequences of a 4°C rise in global temperatures above pre-industrial levels by 2100. And the report appears to have unnerved many bank officials. “The latest predictions on climate change should shock us into action,” wrote World Bank President Jim Yong Kim in an op-ed after the report was released Monday.
The analysis suggests that there is a 20% chance that temperatures will warm to more than 4°C by 2100, possibly reaching g 4°C by 2060. This would result in sea level rise of up to 3 feet, maybe more. If the warming reached 6°C, which is possible, sea level rise would be in the range of a dozen feet or more. The report also discusses the uneven distribution of imacts:
Even though absolute warming will be largest in high latitudes,
the warming that will occur in the tropics is larger when compared to the historical range of temperature and extremes to
which human and natural ecosystems have adapted and coped.
The projected emergence of unprecedented high-temperature
extremes in the tropics will consequently lead to significantly
larger impacts on agriculture and ecosystems.
Sea-level rise is likely to be 15 to 20 percent larger in the tropics than the global mean.
Increases in tropical cyclone intensity are likely to be felt
disproportionately in low-latitude regions.
Increasing aridity and drought are likely to increase substantially in many developing country regions located in tropical
and subtropical areas.
The report is sobering. Let us hope it is also inspiring. You should have a look at it.
You may have heard that the release of greenhouse gases has recently gone down, to match levels of several years ago. Why, then, do we have someone saying that greenhouse gasses have reached a new record high?
There are two, maybe three, reasons.
First, even though CO2 release from the US may be lower now than it has been in a few years, it is still high (it was high a few years ago, so we’ve reduced to a level that is high!). More importantly, the US has reduced its release of CO2 primarily for incidental economic reasons. With a recession/depression going on, there is less money being spent on things that burn fuel. But, we are also producing more fossil carbon-containing products that we send to other countries, where that fuel is burned, thus releasing the CO2. So, globally, CO2 release is probably as high as it has ever been, more or less.
Second, the greenhouse gasses stay in the atmosphere for a long time. Releasing less does not make what is there go away, really. So if we add less for a couple of years, we still increase the amount.
Greenhouse Gas Concentrations Reach New Record: WMO Bulletin highlights pivotal role of carbon sinks
Geneva, 20 November (WMO) – The amount of greenhouse gases in the atmosphere reached a new record high in 2011, according to the World Meteorological Organization. Between 1990 and 2011 there was a 30% increase in radiative forcing – the warming effect on our climate – because of carbon dioxide (CO2) and other heat-trapping long-lived gases.
At this point I would like to pause and note something important. Here we learn that there has been a 30% increase in warming effects from 1990 onward. This does not mean, however, that Anthropogenic Global Warming (AGW) started in 1990. You will often see Climate Science Denialists refer to events earlier in the last 100 years as evidence that global warming is not real. If global warming supposedly causes large storms, and there was a large storm in the 1930s, or if global warming supposedly causes droughts, and there was the Dust Bowl in the 1930s, then global warming is not real, the story goes. However, global warming is largely the result of the release of Carbon from the burning of coal and petroleum, and that (especially the coal) started way back in the 18th century and really took off in the mid 19th century. Global warming and its effects have certainly been much more significant over the last several decades, but the effects are much older than that. To return to the UN report…
Since the start of the industrial era in 1750, about 375 billion tonnes of carbon have been released into the atmosphere as CO2, primarily from fossil fuel combustion, according to WMO’s 2011 Greenhouse Gas Bulletin, which had a special focus on the carbon cycle. About half of this carbon dioxide remains in the atmosphere, with the rest being absorbed by the oceans and terrestrial biosphere.
“These billions of tonnes of additional carbon dioxide in our atmosphere will remain there for centuries, causing our planet to warm further and impacting on all aspects of life on earth,” said WMO Secretary-General Michel Jarraud. “Future emissions will only compound the situation.”
“Until now, carbon sinks have absorbed nearly half of the carbon dioxide humans emitted in the atmosphere, but this will not necessarily continue in the future. We have already seen that the oceans are becoming more acidic as a result of the carbon dioxide uptake, with potential repercussions for the underwater food chain and coral reefs. There are many additional interactions between greenhouse gases, Earth’s biosphere and oceans, and we need to boost our monitoring capability and scientific knowledge in order to better understand these,” said Mr Jarraud.
“WMO’s Global Atmosphere Watch network, spanning more than 50 countries, provides accurate measurements which form the basis of our understanding of greenhouse gas concentrations, including their many sources, sinks and chemical transformations in the atmosphere,” said Mr Jarraud.
The role of carbon sinks is pivotal in the overall carbon equation. If the extra CO2 emitted is stored in reservoirs such as the deep oceans, it could be trapped for hundreds or even thousands of years. By contrast, new forests retain carbon for a much shorter time span.
The Greenhouse Gas Bulletin reports on atmospheric concentrations – and not emissions – of greenhouse gases. Emissions represent what goes into the atmosphere. Concentrations represent what remains in the atmosphere after the complex system of interactions between the atmosphere, biosphere and the oceans.
CO2 is the most important of the long-lived greenhouse gases – so named because they trap radiation within the Earth’s atmosphere causing it to warm. Human activities, such as fossil fuel burning and land use change (for instance, tropical deforestation), are the main sources of the anthropogenic carbon dioxide in the atmosphere. The other main long-lived greenhouse gases are methane and nitrous oxide. Increasing concentrations of the greenhouse gases in the atmosphere are drivers of climate change.
The National Oceanic and Atmospheric Administration’s Annual Greenhouse Gas Index, quoted in the bulletin, shows that from 1990 to 2011, radiative forcing by long-lived greenhouse gases increased by 30%, with CO2 accounting for about 80% of this increase. Total radiative forcing of all long-lived greenhouse gases was the CO2 equivalent of 473 parts per million in 2011.
The report goes on to state that CO2 is the single most important human generated greenhouse gas, but also discusses methane, which I mentioned above, and discusses Nitrous oxide as well.
(Thanks to Brad Johnson for the info on hydrocarbon exports.)
I would almost count it unethical that the New Scientist has a thing that looks like a blog post (an article you can comment on) that has some science in it, but that you have to be a paid subscriber to comment on. WTF New Scientist? What are you trying to pull?
But that’s OK, I’ve got a blog and can comment here.
THE world has been suffering more droughts in recent decades, and climate change will bring many more, according to received wisdom.
“Received Wisdom” means stuff we were told, passed down to us from authority or tradition, that we accept generally unquestioned and that becomes part of our belief system even if the science or other data does not support it. Pearce either thinks that the global warming-drought link was made up and passed on (by whom? I don’t know) as opposed to being the result of consideration and research by involved and knowledgeable scientists, or he does not know what “Received Wisdom” means. Either way, this should be clarified.
Now it is being challenged by an analysis that questions a key index on which it is based.
Predictions of megadroughts affecting Africa and the western side of North America may be wrong. We could even be headed for wetter times, says Justin Sheffield of Princeton University.
What you are seeing here is a misdirection used by many climate change science denialists, having to do with the time frame of global warming. Droughts affecting Africa are predicted? Sorry, guy, but they’ve happened already and are in progress now. The link between global warming and drought has to do with the regional water cycle, and the idea that if things warm up you get more evaporation in some regions and higher concentration of rainfall, so drought and floods ensue. If you look at the temperature-specific effects of global warming by region, you’ll see that certain areas of Africa and souther hemisphere land masses show more warmth earlier, and they also show more drought earlier. The idea that the effects of global warming are something of the future is a standard denialist lie, and I’m thinking Fred Pearce doesn’t know that. Droughts in Africa, the circum Mediterranean region, and Australia are old news, and the link to global warming is highly likely.
The problem with the PDSI, says Sheffield, is that it does not directly measure drought. Instead, it looks at the difference between precipitation and evaporation. But since evaporation rates are hard to determine, it uses temperature as a proxy, on the assumption that evaporation rises as it gets hotter.
Mostly, that is a reasonable assumption, holding ambient moisture in the air constant, because of physics and stuff.
Sheffield points out that temperature is only one factor influencing evaporation. He inferred evaporation rates using the Penman-Monteith equation, which includes factors such as wind speed and humidity, and found “little change in global drought over the past 60 years” (Nature, DOI: 10.1038/nature11575). His new calculations back up his own previous analysis that the most significant of recent droughts mostly occurred in the 1950s and 60s, before global warming got going.
If global warming increases evaporation and changes the water cycle to cause drought, then why have we ruled out droughts in the 50s and 60s as irrelevant? There is a general pattern. Climate on a round planet with a sun (like this one) will tend to be driven by equatorial factors, and similarly, the effects of global warming have probably worked their way out from the equator. Ruling out drought in the 50s and 60s, one hundred years after the start of wholesale burning of coal, is rather absurd. Some effects of Global Warming have become very strong in recent decades, especially in the Arctic, but others have been more slow and steady during the entire time of industrial burning of mainly coal. Sea level rise should give a good indicator of whether or not Global Warming is a thing that only counts from 1970, as the article implies. Let’s have a look at that:
I chose that graph because it is one used by global warming denialists to deny that global warming is real by pointing out that an alleged change that would come with global warming happened before their imagined start of climate change (recently). But no, this is a phenomenon that has been going on for a while.
So, no, major events that have fundamentally changed the distribution of bioms in the 1950s and 60s near the Equator can not be disassociated from this process.
It may well be that the PDSI is not the best measurement for drought, but the arguments made here by the New “Scientist” reek of global warming denialist illogic. I look forward to a spirited discussion among actual drought experts over the coming days. If there is something interesting, I’ll report back.
Meanwhile, New Scientist, you should let people comment on the stuff you put out freely. Paid-to-comment in a world where no one else does that produces the appearance of bias. I would think you would not want to do that.
One of the most commonly winged-about facts of Earth’s climate change we hear from science denialists is that sea ice in the Antarctic is increasing, therefore, there is no global warming. The fact that every other measurement of temperature and ice-osity indicates warming and melting would make a normal person think of the Antarctic situation as odd, and seek explanations, but somehow this logic does not emerge in the minds of the denialists. It has been suspected, and increasingly confirmed, for some time that the increase in sea ice in the Antarctic is the result of changes in wind patterns that cause a local increase in ice while at the same time the planet warms. New research from NASA and the British Antarctic Survey adds to this understanding. From a NASA press release:
NASA and British Antarctic Survey scientists have reported the first direct evidence that marked changes to Antarctic sea ice drift caused by changing winds are responsible for observed increases in Antarctic sea ice cover in the past two decades. The results help explain why, unlike the dramatic sea ice losses being reported in the Arctic, Antarctic sea ice cover has increased under the effects of climate change.
Research scientists Ron Kwok of NASA’s Jet Propulsion Laboratory, Pasadena, Calif., and Paul Holland of the Natural Environment Research Council’s British Antarctic Survey, Cambridge, United Kingdom, used maps created by JPL from more than five million individual daily ice-motion measurements. The data, captured over a period of 19 years by four U.S. Defense Meteorological satellites, show, for the first time, long-term changes in sea ice drift around Antarctica.
“Until now, these changes in ice drift were only speculated upon, using computer models of Antarctic winds,” said Holland, lead author of the study published this week in the journal Nature Geosciences. “This study of direct satellite observations shows the complexity of climate change. The total Antarctic sea ice cover is increasing slowly, but individual regions are actually experiencing much larger gains and losses that are almost offsetting each other overall.
“We now know that these regional changes are caused by changes in the winds, which, in turn, affect the ice cover through changes in both ice drift and air temperature,” he continued. “The changes in ice drift also suggest large changes in the ocean surrounding Antarctica, which is very sensitive to the cold and salty water produced by sea ice growth.”
Holland said sea ice around Antarctica is constantly being blown away from the continent by strong northward winds. “Since 1992, this ice drift has changed,” he said. “In some areas, the export of ice away from Antarctica has doubled, while in others it has decreased significantly.”
Sea ice plays a key role in Earth’s environment, reflecting heat from the sun and providing a habitat for marine life. At both poles, sea ice cover is at its minimum during late summer. However, during the winter freeze in Antarctica, this ice cover expands to an area roughly twice the size of Europe. Ranging in thickness from less than three feet (a meter) to several meters, the ice insulates the warm ocean from the frigid atmosphere above.
This new research also helps explain why observed changes in the amount of sea ice cover are so different in the two polar regions. The Arctic has experienced dramatic ice losses in recent decades, while the overall ice extent in the Antarctic has increased slightly. However, this small Antarctic increase is actually the result of much larger regional increases and decreases, which are now shown to be caused by wind-driven changes. In places, increased northward winds have caused the sea ice cover to expand outwards from Antarctica. In contrast, the Arctic Ocean is surrounded by land, so changed winds cannot cause Arctic ice to expand in the same way.
“The Antarctic sea ice cover interacts with the global climate system very differently than that of the Arctic, and these results highlight the sensitivity of the Antarctic ice coverage to changes in the strength of the winds around the continent,” said Kwok.
Climate change has had contrasting impacts across Antarctica in recent decades. The Antarctic Peninsula has warmed as much as anywhere in the Southern Hemisphere, while East Antarctica has shown little change or even a small cooling around the coast. The new research improves understanding of present and future climate change. The authors note it is important to distinguish between the Antarctic Ice Sheet – glacial ice – which is losing volume, and Antarctic sea ice – frozen seawater – which is expanding.
The research was funded by NASA and the Natural Environment Research Council.
October was, nationally in the US, kinda cold. Not record cold, but colder than average. However, as Jeff Masters at Weather Underground has calculated, we would have to have some kind of Snowball Earth scenario kick in for December in order for 2012 to not be the warmest year on record in the US. Here, you can read about it yourself.
In the mean time, there is an interesting weather related production coming up you may want to know about. First, check this out:
I am sure that by now you know about ScienceDebate Dot Org. It was set up for the 2008 US presidential election by a bunch of people including my friend Shawn Otto. The idea is to simultaneously push for an actual debate focussed on science and science policy as part of the presidential election process, and to make people realize that such a thing, which is not happening, is important.
We’ve had a couple of elections now that were almost overshadowed by major storms, the most recent, Sandy, being as much of a direct effect of Global Warming (a scientific issue) as any large storm ever was, since it was both strengthened by Atlantic warm waters (caused by Global Warming) and directed to New Jersey and New York by blocking features in the atmosphere that seem to have emerged from the lack of Arctic Ice (caused by Global Warming). Ya. Global warming killed over 100 Northeasterners and did a gazillion dollars in damage in one day. It is relevant. Let me say that again. It. Is. Relevant. And solving this sort of problem is a matter of science and science policy, and it is not being discussed enough.
Science Debate OK has put out a report to stakeholders, in the form of a simple web page with many useful links. It is here. Go have a look.
The time to join up with effort a propos the next presidential election is now, not later. Also, I would hope we can do things between now and then, perhaps pertaining to midterm Congressional elections.
The term “War on Science” comes from multiple sources, one being Chris Mooney’s book “The Republican War on Science” (see below) and another, the made up “War on Christmas,” a term attributed to Bill O’Really. Throw in a little “Culture War” rhetoric and I think we have a good basis for the origin of the term. The term “War on X” has been in used for decades if not longer, when some large perhaps organized group of people or institutions takes up the task of shutting down some thing or another. It does not mean an actual war with generals and troops and bullets, but the metaphor “war” is still quite apt because there are generals and troops and bullets, just metaphorical ones.
Anyway, I thought it would be a good idea to provide a list of current or recent books and other resources pertaining to the war on science. Where I’ve reviewed a book here, I provide a link to that review. There are also some helpful web sites and podcasts listed below. The listing of resources is divided up by “front” or “battle ground” where appropriate, keeping with the “War on Science” metaphor.
Disclaimer: The comment that we have a new kind of storm is not a conclusion, but a hypothesis, though it does not sound that way from the way I said it. But now you know.
If you are in the path…the thousand mile wide path…of Hurricane Sandy, a.k.a. Frankenstorm, then you should make sure you know what the storm could do in relationship to where you are. If you are in or near an area with mountains, look for very serious flash flooding. The winds will be strong everywhere. If you are near the coast, be aware that the highest storm surges seen in years are expected in many areas. At the same time, it is important for those of us writing or talking about this storm to be realistic and careful in making predictions. This is becasue every case of dire prediction that does not materialize is a morsel of ignorance that will be served up later by climate change denialists who profit from confusing the general public about the connection between climate change and storminess. Here, I’d like to do the following: Give a brief overview of what Sandy is all about; address the question “Can you attribute Sandy or any other large storm to Global Warming?”; and tell you about some recent research related to that question. I’ll also throw in a little bit of historical background by way of discussing a nightmare scenario that actually didn’t happen.
Nightmare Storms
First the nightmare scenario. Years ago, my first long distance trip anywhere not involving aircraft was a road trip from Albany, NY to the Southeast, the Southwest, California, and back. This was in the 1970s, and it took months. On the way out, I encountered a storm in Texas that stranded me there, in Big Spring, for several days. The state was covered with a layer of ice, and there was no way to handle it. Months later, on the way back, I drove through the aftermath of that storm and a very long time after the storm had passed though, there were still wrecked semis littering Routes 30 and 40.
I did not live in Boston at the time, but that was the year Boston was hit with a very severe storm, was part of the same system that iced the Lone Star State. In Boston, so much snow fell during rush hour that the cars on the major beltways that go around the urban core were trapped in situ. People died of exposure in their own cars, or en route on foot to “safety” from more remote parts of the road. Hundreds of homes and cabins along the coast were destroyed.
That was one of several storms leading to changes in zoning and regulation along the north Atlantic coast in the US which led to no more building and in some cases the aggressive removal of structures on the open coast or barrier islands. A couple of years later I did move to the coast, and spent a fair amount of time on the shores of Cape Cod, Plumb Island and elsewhere. As an archaeologist, I fully enjoyed encountering the remains of homes or small settlements. There would be nothing standing, but the remains of houses and their contents would be poking up here and there. It was always interesting to try to figure out based on the position and location of the largest bits where the home may have originally sat, and based on the degree of deterioration of the remains, which of the recent storms had destroyed the home or cabin.
One of the great historical events one learns of while working, in historic preservation and archaeology in New York and New England is the Great Storm of 38. The big storm in the 70s happened 35 years ago, and 35 years or so before that a storm came up the Atlantic, crossed Long Island, slammed into Rhode Island and Southeast Massachusetts, and generally made a mess of the interior, destroying lots of homes and killing lots of people. We now think it was a hurricane, but the people of New England at the time, including fisherfolk who’s lives and livelihood depended on the sea and on knowledge of the weather, had not even heard of a “Hurricane” before. Surely, hurricanes had come up the coast before, but with such infrequency that they were not a named phenomenon. Just another (big) storm. Years after the Storm of ’38, when I was busy climbing all the High Peaks in the Adirondack Mountains, I was often challenged by “slides” and blowdowns caused by that storm. Anyone who knows the ADK’s of the 1960s and 1970s or earlier knows of the big slides on Giant and the other steep sloped mountains, and the blowdowns on the Dix range. Those features of hiking and climbing are mostly courtesy of the big storm of ’38.
Here’s the thing. Imagine that a storm like Sandy came along in either of two years; 70 years ago or 35 years ago. Sandy is much larger and contains much more energy than the ’38 storm, or for that matter, of any known storm of the North Atlantic (we’ll get to that below). If Sandy hit the region in the 1930s, it would have been without warning, and it would have been prior to the reconstruction of seawalls and the development of flood mitigation measures inland that have happened in recent decades. Sandy, in ’38, would kill tens of thousands and destroy thousands of structures. That would be an average Sandy, a Sandy not being as bad as the most dire predictions we are considering today as the storm begins to take a grip on the eastern seaboard.
A Sandy of 35 years ago would have been predicted. The ability to see hurricanes coming was in place, but not as well developed as it is today. We would have seen Sandy coming, but her massiveness and extent, and her exact trajectory, would probably have been unknown. But at least there would be warning. Many of the seawalls and flood mitigation systems would have been in place, but the overbuilding on barrier islands and other vulnerable coastal regions would have been at or near a peak. With evacuations, Sandy would not kill 10s of thousands… probably only hundreds. But the number of buildings destroyed would be unthinkable. Most of those buildings are now gone or shored up. A Sandy in 1975 would have left some very interesting coastal archaeology for me to have observed during my trips to the shore in the 1980s. Very interesting indeed.
Do you remember the October storm of 1991, a.k.a., the Halloween Nor’easter a.k.a. The Perfect Storm? I do. I was living in Somerville, Ma. After the storm raged for hours and finally calmed down a bit I went out for a walk. Power lines and large tree fragments littered the landscape. There would be no driving for a day or two in many neighborhoods. I was able to get out the next day, and I drove right up to Cape Anne, near Gloucester (Bass Point to be exact), where the Andrea Gail had sailed from never to return. I had not heard about the Andrea Gail yet but I went down to Glouscter to see the waves.
Is Sandy Caused By Global Warming?
I remember parking the car along side the road, and climbing over a granite riprap structure to get to the shore. I stood on that high point, and from there could see a few dozen people milling around at a much lower elevation, taking pictures of the waves that were rolling in. I did a rough calculation. How far inland would a wave wash if it was double the size of those I could see now? Double and triple size waves … rogue waves … would not be unlikely after a storm like this. When I realized that my shoes would probably get wet, and all the people down at a lower elevation would probably get washed away, if that happened, I went back to the car and drove to the clam shack in Ipswich for lunch. Later that day, I hear, the authorities cleared the beaches. The waves I was watching were 10 meters if they were a centimeter. Indeed, 30 meter waves were recorded asea in Nova Scotia, and high waves killed a couple of looky-loos on Staten Island. That storm was one of several that hit New England since the big storm of the 1970s. Everybody who lives in the region knows that the storms have become more common and more severe, and probably lager, wider, in extent.
But is there any evidence to support that?
Well, yes, actually, there is. Here’s the abstract from a recent paper:
Detection and attribution of past changes in cyclone activity are hampered by biased cyclone records due to changes in observational capabilities. Here we construct an independent record of Atlantic tropical cyclone activity on the basis of storm surge statistics from tide gauges. We demonstrate that the major events in our surge index record can be attributed to landfalling tropical cyclones; these events also correspond with the most economically damaging Atlantic cyclones. We find that warm years in general were more active in all cyclone size ranges than cold years. The largest cyclones are most affected by warmer conditions and we detect a statistically significant trend in the frequency of large surge events (roughly corresponding to tropical storm size) since 1923. In particular, we estimate that Katrina-magnitude events have been twice as frequent in warm years compared with cold years (P < 0.02).
So, over the years, it gets warmer and colder and in warmer years there is more stormosity, as it were. Warm=storm. At the same time, the amount of warm (number of warm years and how warm they are) has been going up. More storms over time, just as any honest Salt can tell you. Here’s a nice graph from the same paper: (A) Average surge index over the cyclone season. (B) Observed fre- quency of surge events with surge index greater than 10 units/y (surge index > 10 units) and linear trend (black). (C) Accumulated cyclone energy for US landfalling storms. (D) Annual average global mean surface temperature anomaly from GISTEMP (23), shaded to show warmer and colder than median temperatures. Thick lines in A, B, and C are 5-y moving averages. Inset in A shows locations of the six tide gauges used in the construction of the surge index.
Now, here is what you’ll hear a lot of people say. People will tell you that “you can’t attribute any given storm to global warming.” There is a certain way in which that is true, but there is also a certain way in which it is wrong, and the importance of recognizing the relationship between global warming and storminess is now so important that the former has become little more than a pedantic nuisance and we’d better start focusing on the latter.
One of the reasons why this statement is true is a little unfair to those saying it, or for that matter to the phrase itself, and is extrinsic to the logic of the statement itself, yet is still a valid reason. Here’s the thing. People often say “Well, you can’t attribute a given weather event to climate change” or, more importantly, people often hear that said, and then in their brains a disconnect between climate and weather is established or verified. In other words, people use that phrase to give themselves permission to not worry about climate change vis-a-vis storminess. One might argue that it does not matter that people use this phrase incorrectly, it is still true. But it does matter a great deal because the bigger, overwhelmingly important issue is the lack of social and political will to tackle global warming as a problem. Phrases that are a) technically true but b) miss the point and c) contribute to the end of civilization do not deserve our protection. Just. Stop. Saying. It.
The other way to look at it, the way in which we might fairly and logically say that warming weather can be said to be the cause of a particular storm, is best viewed in a thought experiment first. Suppose there were no Nor’easters, like Sandy. Suppose hurricanes were never, ever known to travel north of Georgia and were not that common. Now, imagine that we warm the world up a bit and this warming causes Nor’easters to start to form, and it causes hurricanes to start heading farther north, and then, some of those Nor’easter low pressure systems combine with some of those hurricanes and cause Frankenstorms.
Those Frankenstorms were caused by global warming.
In a world in which storms generally are more severe, more common, bigger, go farther north, or do some other nasty trick (any subset of this list may pertain, it is not necessary that all are true), one might well ask the question: “Is there any way to say that a given North Atlantic Frankenstorm emerged from the sea and the atmosphere without any of the added energy of global warming contributing to the severity, size, and northerly track of that storm?” And the answer is, “No, of course not, don’t be a bonehead.”
It is often said that storms are going to happen anyway, but global warming ramps up the probability, which is akin to saying that there is always going to be variation in temperature or some other weather related factor but global warming raises the baseline. That’s true. But the corollary to that is NOT that you can’t link climate change to a given storm. All storms are weather, all weather is the immediate manifestation of climate, climate change is about climate. Before we started talking about global warming, storms were caused by … things. Climate things. Did we ever say, back in the 1950s when a hurricane hit Florida, “Oh, ya, that was some hurricane, but the thing is, you can’t really attribute a given hurricane to the Intertropical Convergence Zone’s relationship to warm Mid Atlantic currents. The former is a weather event and the latter is a climate system.” Why did we not ever say that? Because it would have been irrelevant, even dumb.
The truth is, we experience more Atlantic severe storms because of global warming, though we are still working out the details of which features of which kinds of storms are affected most. Beyond this, it may well also be possible that something I hinted at above is true: We may be experiencing kinds of storms today that were very rare in recent centuries, because of global warming.
In any event, there’s more. From the paper:
We detect a statistically significant increasing trend in the number of moderately large surge index events since 1923. We estimate that warm years have been associated with twice as many Katrina-magnitude events compared with cold years in the global average surface temperature record.
Jeff Masters, at The Wunderblog, has an excellent post on Sandy, what’s going on now, and what might happen. It is here. Keep in mind that by the time you click through to that he may have put up a newer post, so check for that. Meantime, here’s a few salient items you may want to know about:
Sandy, the storm, is of record size, larger than any storm ever seen before. It is over 1,000 miles wide, with 12 foot seas covering that entire area. There’s been a couple of storms with this or that dimension exceeding Sandy, but in some other way they fell short. Sandy wins.
You already know about the whole “landfall” problem with storms, so I won’t go into this here. The thing is, even while Sandy’s worst rains and winds are no where near the coast, she is putting up storm surges already, and roads are being washed away as we speak with days of storminess ahead of us. (This is the thing about “Nor’easters… they go on for much longer than mere hurricanes!)
Sandy will generate modest storm surges from South Carolina to Canada, with severe storm surges from Delaware to Massachusetts.
The storm surge in New York City may be higher than ever seen before, and has about a 50-50 chance of flooding the subway system in the vicinity of the Battery. That has never happened before.
Tropical force winds will batter 1000 miles of coast on Monday and Tuesday, with hurricane force winds covering a 500 mile section of coast.
Remember all the flooding associated with Irene in 2011? Sandy will also cause major inland flooding, but not as much rain overall will fall, so overall the flooding will be less. However, what “less” means is relative. If you are in a hilly region of Pennsylvania or some other part of the northeast, you may well experience worse flooding with Sandy than you did with Irene. Or not. Overall, there will be less, but it will still be bad.
And yes, there will be snow. The usual places that get snow during Nor’easters are at risk. Any place with a high elevation or that is up north has a good chance of getting a few inches, or in some cases, a couple of feet.
I found it very interesting that the Maya recently came out to ask people to stop suggesting that somehow their cyclic calendar was going to cause the end of civilization, or the world, or whatever, at the end of the present year. This is a case of a traditional people well versed in their own indigenous technology (in this case, time tracking technology) noticing that the “civilized Western world” was making a major fool of itself, as usual, and then helpfully suggesting that certain people STFU. At the same time, we are doing it wrong for real and truly putting the future at risk, and not just with climate change, but how we address climate change. We are not making it part of the conversation in national elections, we are not making it part of our budget considerations, we are not making it part of our shovel-ready-stimulus activities. We are not even letting ourselves keep track of what we are ruining. The number of satellites that will be available to track storms like this will probably fall off in the near future to the extent that we won’t be able to do it. Talk about the end of civilization! Even if we didn’t simply screw up plans for putting up more satellites, we have this other growing problem with space junk. Our technology is warming our planet and at the same time blinding us, hampering our ability to manage the problem we are creating.
Stay safe.
Grinsted, A., Moore, J., & Jevrejeva, S. (2012). Homogeneous record of Atlantic hurricane surge threat since 1923 Proceedings of the National Academy of Sciences DOI: 10.1073/pnas.1209542109
This has been known for years. It is very frustrating to see people ask questions like “well, what we don’t know is what will global warming do?” Global warming has done, already, quite a bit and it is insulting to our collective intelligence and an affront to the families of those who have died from it to pretend nothing has happened. From desertification in Africa to heat waves in Chicago, global warming has killed people. Perhaps the following video from PBS will make this a bit more palpable to those who can’t grasp this concept.
? I do. I was living in Somerville, Ma. After the storm raged for hours and finally calmed down a bit I went out for a walk. Power lines and large tree fragments littered the landscape. There would be no driving for a day or two in many neighborhoods. I was able to get out the next day, and I drove right up to Cape Anne, near Gloucester (Bass Point to be exact), where the Andrea Gail had sailed from never to return. I had not heard about the Andrea Gail yet but I went down to Glouscter to see the waves.