Tag Archives: Climate Change

Climate Change as a National Security Threat

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The White House has issued a press release noting that President Obama will address climate change as a national security threat in a speech later today in Connecticut. Here is the press release.

White House Report: The National Security Implications of a Changing Climate
Today, President Obama will travel to New London, Connecticut to deliver the commencement address at the United States Coast Guard Academy. During his speech, the President will speak to the importance of acting on climate change and the risks to national security this global threat poses. The White House also released a new report on the national security implications of climate change and how the Federal government is rising to the challenge.

As the President has made very clear, no challenge poses a greater threat to future generations than climate change, as we are already seeing these threats in communities across the country. We know that climate change is contributing to extreme weather, wildfires, and drought, and that rising temperatures can lead to more smog and more allergens in the air we breathe, meaning more kids are exposed to the triggers that can cause asthma attacks.

But as the President will stress, climate change does not respect national borders and no one country can tackle climate change on its own. Climate change poses immediate risks to our national security, contributing to increased natural disasters and resulting in humanitarian crises, and potentially increasing refugee flows and exacerbating conflicts over basic resources like food and water. It also aggravates issues at home and abroad including poverty, political instability and social tensions – conditions that can fuel instability and enable terrorist activity and other forms of violence.

The Department of Defense (DOD) is assessing the vulnerability of the military’s more than 7,000 bases, installations and other facilities to climate change, and studying the implications of increased demand for our National Guard in the aftermath of extreme weather events. Two years ago, DOD and DHS released Arctic Strategies, which addresses the potential security implications of increased human activity in the Arctic, a consequence of rapidly melting sea ice.

But we also need to decrease the harmful carbon pollution that causes climate change. That is why, this summer, the EPA will put in place commonsense standards to reduce carbon pollution from power plants, the largest source in the United States. Today, the U.S. harnesses three times as much electricity from the wind and twenty times as much from the sun as we did since President Obama took office. We are working with industry and have taken action to phase down HFCs and address methane emissions in the oil and gas sector. By the middle of the next decade, our cars will go twice as far on a gallon of gas, and we have made unprecedented investments to cut energy waste in our homes and buildings. And as the single largest user of energy in the United States, DOD is making progress to deploy 3 gigawatts of renewable energy on military installations by 2025.

Live Blogging Climate Denial 4: The Best Week So Far

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… because it is Paleo!

Paleo data, models, expectations, observations, about the past and to some extent the future. The Little Ice Age. The Hockey Stick. And, what people get wrong about it all.

Denial101x Making Sense of Climate Science Denial goes paleo (and Medieval) this week. Here is a sample video, Andy Skuce on the Little Ice Age:

Peter Jacobs employs a great analogy of encountering a dangerous bear in the woods to help us understand palaeoclimatology.

Professor Tim Osborn, Professor Michael Mann, Professor Katrin Meissner, Professor Dan Lunt and Professor Isabella Velicogna get down with a lot of details about past climates, proxies like ice cores and corals, and how this all gets linked to more recent thermometer data. Michael Mann talks about development of the the Hockey Stick research. The nature of climate variability over time.

Robert Way on the Medieval Warm Period aka the Medieval Climate Anomaly. Lots of great denialism about this topic!

What does the term “Hide the decline” really mean? Get the real story from the real scientists, Michael Mann and Tim Osborn:

Dana Nuccitelli explains what models are all about. Professor Dan Lunt of the University of Bristol, Professor Andrew Pitman of the University of New South Wales and Professor Katrin Meissner of the University of New South Wales also talk about climate models.

OMG the 1970s Ice Age Myth!!!! Daniel Bedford explores what really happened in climate science in that decade:

See also this: The 1970s Ice Age Myth and Time Magazine Covers – by David Kirtley

Denial 101x Week 3

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A few notes from Week 3 of Denial 101x: Making Sense of Climate Science Denial. These notes are mainly about the science and not the denialism part (unlike my last post, which addressed the central theme of the course, denialism, more.)

The Carbon Cycle

Atmospheric CO2 concentrations have gone up by about 40%. Simple explanation: Humans are releasing Carbon into the atmosphere by burning fossil fuel. More complex explanation: Humans are affecting the Carbon Cycle in a number of ways, releasing Carbon (burning fossil fuels) as well as affecting natural Carbon sinks.

This became known, observed, ca 1958. About half of the CO2 we release contributes to the extra atmospheric CO2. Myth: Since the amount of Carbon that cycles naturally through the system is so large, human influence must be negligible. Good analogy using a bank account. Nature has been a net Carbon sink over the last 50 years, but we are still seeing atmospheric CO2 going up.

A video by Gavin Cawley:

Andy Skuce discussed the role of volcanoes in comparison to human effects. Great discussion of the big picture for volcanoes. Did you know that most of the volcanoes are under the sea? But on balance the way undersea volcanoes work actually results in a lot of CO2 being consumed there. Mt Etna is one of the more prolific CO2 producers, but is still smaller than human fossil fuel burning in nearby Sicily. Also, 1/3rd of land based volcano CO2 is off set by weathering of volcanic surfaces. Humans release 60-100 times more Carbon than volcanoes.

Gavin Cawley talks more about the Carbon Cycle, asking the question, how long would it take the Carbon Cycle to return CO2 to pre-industrial levels is humans got out of the game today. Myth: CO2 has a short lifespan in the air. A given CO2 molecule may have a short lifespan but the amount of CO2 does not change quickly. Jelly Beans are invoked in a helpful analogy. Answer: It is a slow process that will take 50-200 years for much of it to return, but the total adjustment time is a long time, thousands of years. Also, Gavin Cawley and his wife need to talk more about heir checkbook and their private jelly bean stash.

Dr Joanna House, Corinne Le Quéré, Professor Tim Osborn, Professor Dan Lunt, Professor Lonnie Thompson, Professor Pierre Friedlingstein and Professor Mauri Pelto talk about the Carbon Cycle. Seasonal cycles, longer term cycles. Plants, ocean, etc. Natural fluxes are roughly in balance, human emissions provides a rapid positive flux. We have not had this CO2 level in 800 thousand years. NOTE: That does not mean that 800K years ago CO2 was at 400ppm. It is just that we have a good ice core record 800K long. To reach 400ppm you have to go back much farther in time, millions of years. The time scale for ocean mixing is thousands of years. About 65 – 80% of the human released CO2 will go away (if humans go away) in between 2 to 200 years. The remaining 35 percent (on average) will take thousands of years.

Greenhouse Effect

Mark Richardson: Pig picture, i.e., different planets. Good description of how the greenhouse effect works. Cool infrared camera demonstration. A pygerometer.

Mark Richardson: Looking at the first ever greenhouse effect myth, dates back to 1900. “Knut Ångström and his assistant did an experiment.” It seemed to show that the effects of CO2 could saturate. It does but not at actual relevant levels in the atmosphere.

Sarah Green about reinforcing feedback. Chicken-egg problems, causality. What do Ice Cores say about changes in the Carbon Cycle over long periods of time. Does warming increase CO2, or does increased CO2 cause warming? Yes. False dichotomy myth. This is pretty important and a bit complex, so I’ll just put the video here:

From the experts, Professor Naomi Oreskes, Dr Ed Hawkins, Professor Mike Mann, Professor Simon Donner, Professor Richard Alley, Professor Eric Rignot, Professor Jonathan Bamber and Professor Lonnie Thompson talk about the greenhouse effect, the history of research on the greenhouse effect, etc. Excellent video to show Uncle Bob:

Fingerprints

Mark Richardson examines the fingerprint of changing structure of heat distribution in the atmosphere, (including the famous Tropical Hotspot, not a real fingerprint, though may be it is like a partial print). (See this recent post on a related topic.)

Sarah Green on Satellite measurements of outgoing radiation. This is a key fingerprint of changes in energy balance.

Are you taking the course? You should check it out, here.

Seepage: Climate change denial and its effect on the scientific community

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The title of this post is also the title of a new peer reviewed paper by Stephan Lewandowsky, Naomi Orskes, James Risbey, Ben Newell and Michael Smithson, published in Global Environmental Change. The article is Open Access, available here. Stephan Lewandosky has a blog post on it, in which he notes,

… we examine the effect of contrarian talking points that arise out of uncertainty on the scientific community itself. We show that although scientists are trained in dealing with uncertainty, there are several psychological and cognitive reasons why scientists may nevertheless be susceptible to uncertainty-based argumentation, even when scientists recognize those arguments as false and are actively rebutting them….

We highlight three well-known psychological mechanisms that may facilitate the seepage of contrarian memes into scientific discourse and thinking: ‘stereotype threat’, ‘pluralistic ignorance’ and the ‘third-person effect’.

Stereotype threat refers to the emotional and behavioural responses when a person is reminded of an adverse stereotype against a group to which they belong. Thus, when scientists are stereotyped as ‘alarmists’, a predicted response would be for them to try to avoid seeming alarmist by downplaying the degree of threat. There are now several studies that highlight this tendency by scientists to avoid highlighting risks, lest they be seen as ‘alarmist.’

Pluralistic ignorance describes the phenomenon which arises when a minority opinion is given disproportionate prominence in public debate, resulting in the majority of people incorrectly assuming their opinion is marginalized. Thus, a public discourse that asserts that the IPCC has exaggerated the threat of climate change may cause scientists who disagree to think their views are in the minority, and they may therefore feel inhibited from speaking out in public.

Finally, research shows that people generally believe that persuasive communications exert a stronger effect on others than on themselves: this is known as the third-person effect. However, in actual fact, people tend to be more affected by persuasive messages than they think. This suggests the scientific community may be susceptible to arguments against climate change even when they know them to be false.

I have little to add beyond Stephan’s overview (Sou has this, go check it out), and you can read the paper itself. I do think these questions are part of an even larger issue, of the influence of systematic well funded constant denialism on both the science and the implementation of science as public policy. Imagine if all the effort spent addressing contrarian claims was spent on doing more science or the translation of science into policy? One could argue that questioning the science strengthens it, and in many cases that may be true. But the denialism about climate science does not play that role. Contrarian arguments are not valid questions about the science, but rather, little more than self indulgent contrived nefarious sophistic yammering. That is not helpful; It does not strengthen the science. Rather, denialism has served to slow down the implementation of sensible energy policies, and has probably slowed down our collective effort to the extent that were the denialism ignored, or didn’t exist to begin with, we would be decades ahead of where we are now in addressing the existential issue of our time.

A Global Warming Expectation Confirmed: Upper Troposphere Warming

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Note: The original title of this post was “A Global Warming Fingerprint Confirmed: Upper Troposphere Warming” because I was thinking that upper troposphere warming was a fingerprint. John Cook contacted me to let me know that he didn’t think it was. The reason it is not is that more than one thing can cause upper tropospheric warming, not just AGW. However, it does turn out to be more complicated than that. Various people claiming that a lack of UT warming was evidence of no warming have now been shown wrong, but even a lack of warming is not, if you will, an anti-AGW fingerprint. In the end it turns out to be a very complicated phenomenon and it would probably take me five blog posts to adequately related the conversation I’ve had over the last 24 hours with various climate scientists about the details.

John Abraham will be having something on this in the Guardian very soon, I’ll put a link here. An now, back to the original post:

Global warming is real, and caused by the release of human generated greenhouse gas pollution. We can measure the greenhouse gas concentrations (mainly CO2) and we can measure surface warming and upper ocean warming. But global warming should have a number of additional indicators, predicted by modeling or other aspects of climate science, and identifying those indicators both confirms the overall idea of global warming and helps us understand its effects.

The troposphere is the lower layer of the Earth’s atmosphere, where about three quarters of the air and most of the water vapor resides, and it is about 7 to 20 kilometers thick, thickest in the tropics and thinest near the poles. Climate models and thermodynmaic calculus predict that the upper troposphere in the tropics should experience warming. Temperatures at this altitude are measured using radiosonde technology. This is a package of instruments sent aloft on a weather baloon. But there are a lot of problems with the data. Instruments that measure temperature are ideally situated in one spot and properly enclosed. Such instruments dangling off the end of a balloon flying through the air are subject to heating and cooling from various uncontrolled effects, such as sunlight (vs. not), air movements, etc. Given the low quality of the data, it has been hard to observe upper troposphere temperatures.

Satellite measurement of temperature variation in the troposphere are not as useful as one might hope, because those instruments tend to average out temperatures over a much larger area of air than suitable for measuring the expected warming.

The new study, Atmospheric changes through 2012 as shown by iteratively homogenized radiosonde temperature and wind data (IUKv2), by Steven Sherwood and Nidhi Nishant, takes a new approach. From the Abstract:

We present an updated version of the radiosonde dataset homogenized by Iterative Universal Kriging (IUKv2)…This method, in effect, performs a multiple linear regression of the data onto a structural model that includes both natural variability, trends, and time-changing instrument biases, thereby avoiding estimation biases inherent in traditional homogenization methods. One modification now enables homogenized winds to be provided for the first time. ..Temperature trends in the updated data show three noteworthy features. First, tropical warming is equally strong over both the 1959–2012 and 1979–2012 periods, increasing smoothly and almost moist-adiabatically from the surface (where it is roughly 0.14 K/decade) to 300 hPa (where it is about 0.25 K/decade over both periods), a pattern very close to that in climate model predictions. This contradicts suggestions that atmospheric warming has slowed in recent decades or that it has not kept up with that at the surface. Second, as shown in previous studies, tropospheric warming does not reach quite as high in the tropics and subtropics as predicted in typical models. Third, cooling has slackened in the stratosphere such that linear trends since 1979 are about half as strong as reported earlier for shorter periods.

This graphic shows the relative warming of the upper troposphere in the tropics:

Upper_Troposphere_Warming_In_Tropics

This is not the first study showing this, but rather, a significant update clarifying the observations.

Several modifications have been introduced, which have not had a large effect on estimated long-term trends in temperature but have enabled us to present a homogenized wind dataset in addition to that for temperature.

The warming patterns shown in the revised dataset are similar to those shown in the original study except that expected patterns now appear somewhat more clearly. These include a near-moist-adiabatic profile of tropical warming with a peak warming rate of 0.25–0.3 K/decade near 300 hPa since either 1959 or 1979. This is interesting given that (a) many studies have reported less-than-expected tropospheric warming, and (b) there has been a slowing of ocean surface warming in the last 15 years in the tropics. We support the findings of other recent studies … that reports of weak tropospheric warming have likely been due to flaws in calibration and other problems and that warming patterns have proceeded in the way expected from models. Moreover our data do not show any slowdown of tropical atmospheric warming since 1998/99, an interesting finding that deserves further scrutiny using other datasets

Another outcome of this research is the observation of increased winds in the Southern Hemisphere. This increase may be related to Ozone depletion at the southern end of the planet, a phenomenon that may also account for increasing extent of winter sea ice around Antarctica. Quoted in PhysOrg, author Steve Sherwood notes, “I am very interested in these wind speed increases and whether they may have also played some role in slowing down the warming at the surface of the ocean.”

John Abraham has also written up this research, here.

Since we were talking about “fingerprints” I thought you might like to watch this video by John Cook discussing global warming fingerprints. The video is from the MOOC “Denial101x Making Sense of Climate Science Denial”

Bjorn Lomborg’s WSJ Response to Nixing of Australian Project

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Bjorn Lomborg has written an Op Ed in the Wall Street Journal lamenting the decision of the University of Western Australia (UWA) to nix previously developed plans to accept a $4 million dollar payment from the conservative Australian government, to be matched by university money, to implement a version of Lomborg’s Copenhagen Institute there, to be known as Australia Consensus.

See: Bjorn Lomborg Is Wrong About Bangladesh And Sea Level Rise

See: Bjørn Lomborg WSJ Op Ed Is Stunningly Wrong

See: Are electric cars any good? Lomborg says no, but he’s wrong.

Lomborg’s scholarship in the area of climate and energy related policy has been repeatedly criticized and often described as far less than adequate. A typical Bjorn Lomborg missive on climate or energy policy seems to include instance after instance of inaccuracies, often taking the form of a statement of fact with a citation, where that fact or assertion is not to be found in the citation. Many regard his policies as “luke warm.” From the highly regarded Sketpical Science web site:

…examples of Luckwarmers include Matt Ridley, Nic Lewis, and Bjorn Lomborg. The University of Western Australia has been caught up in a major Luckwarmer controversy, having taken federal funds to set up a center from which Lomborg was expected to argue that the government’s money would be better spent on issues other than curbing global warming. In a sign that even Stage 3 climate denial is starting to become untenable, the resulting uproar forced the university to cancel plans for the center.

The UWA project received a great deal of critisim, and was seen by many as a move by Big Fossil to water down academic and government response to the critical issue of climate change. Graham Readfearn, writing for The Guardian, notes:

Danish political scientist and climate change contrarian Bjørn Lomborg says the poorest countries in the world need coal and climate change just isn’t as big a problem as some people make out.

Australia’s Prime Minister Tony Abbott says “coal is good for humanity” and there are more pressing problems in the world than climate change, which he once described as “crap” but now says he accepts.

So it’s not surprising then that the latter should furnish the former with $4 million of taxpayer funds to start an Australian arm of Lomborg’s Copenhagen Consensus Centre (CCC) at the University of Western Australia’s business school.

The Australian project was shut down after severe criticism from the global academic community as well as students and faculty within UWA. Predictably, Lombog had characterized this as an attack on free debate. From the Op Ed, “Opponents of free debate are celebrating. Last week…the University of Western Australia canceled its contract to host a planned research center, Australia Consensus, intended to apply economic cost-benefit analysis to development projects—giving policy makers a tool to ensure their aid budgets are spent wisely.

While Lomborg blames “activists” for shutting down the center, it is more widely believed that the project was criticized because, based on prior work done by Lomborg, any ensuing “cost-benefit analyses” would be academically weak and policy-irrelevant.

Central to the difference in overall approach (aside from allegations of poor scholarship) between Lomborg and many others is how poor or developing nations should proceed over coming decades. Lomborg seems to advocate that these nations go through the same economic and technological evolution as developed nations, building an energy infrastructure based mainly on fossil fuels, in order to industrialize and reach the standard of living presumed desired by those who live in those nations. The alternative, of course, is that development in these regions be done with lessons learned from the industrialized and developed world. We don’t ask rural Kenyans to install a wire-based analog phone system before using modern digital cell phone systems. With respect to energy, developing regions should implement clean energy with smart distribution rather than building hulking coal plants and committing for centuries to come to expensive and extensive electric grid systems that are now generally regarded as outdated.

Lomborg says enough about mitigating climate change effects, and developing green energy technologies, to be able to suggest that he supports these ideas when he is pushed up against the wall, as with the nixing of the Australian project. But his regular statements on specific policy points, frequent and well documented, tell a different story.

Lomborg claims that much of the policy development of the Copenhagen Institute is not even about climate change. To the extent that this is true, it may be part of the problem. As development occurs, energy is key. With development of energy technologies, climate change is key. Lomborg’s approach that the Copenhagen projects are mostly not about climate change is not an argument that he is doing something right. It is evidence that he is doing something wrong, and at the same time, is apparently unaware of this.

It is very important to remember, as this conversation unfolds, that the objections to Lomborg’s work, and to spending vast sums of money to support it, are only partly because of differences in approach. These objections also come from two other things. One is a sense that Lomborg is detached from scholarship and good analysis.

Graham Readfearn has documented academic response to Lomborg’s work. Here is one example:

Dr Frank Jotzo, director of the Centre for Climate Ecnomics and Policy at the Australian National University, was once invited to write a paper for Lomborg’s centre in 2008, which was sharply critical of how the cost of the impacts of climate change were treated.

He told me:

Within the research community, particularly within the economics community, the Bjorn Lomborg enterprise has no academic credibility. It is seen as an outreach activity that is driven by specific set of objectives in terms of bringing particular messages into the public debate and in some cases making relatively extreme positions seem more acceptable in the public debate.

And, regarding energy policy vis-a-vis the Big Fossil,

…we had a look at Lomborg’s claims that the world’s poorest were crying out for more fossil fuels which, Lomborg argued, were the only real way they could drag themselves out of poverty…the positions Lomborg takes on these issues are underpinned by a nasty habit of picking the lowest available estimates of the costs of climate change impacts.

Last year, when Lomborg spoke to a coal company-sponsored event in Brisbane in the shadow of the G20 talks, Lomborg suggested that because the International Energy Agency (IEA) had developed one future scenario that saw growth in the burning of coal in poor countries, in particular in sub-Saharan Africa, that this somehow meant that fossil fuels were just what they needed.

Yet Lomborg ignored an important rejoinder to that assessment, which had come from the IEA itself, and which I pointed out at the time.

The IEA said its assessment for Africa was consistent with global warming of between 3C and 6C for the continent by the end of this century.

Lomborg’s prior written works could be, and actually have been (I am told), used in coursework on analytical approaches to policy as bad, not good, examples. And, although Lomborg often associates himself with Nobel Prize Winners (and rarely fails to note that) he is not known as a high powered, influential scholar in his area. A recent citation analysis of Lomborg’s work backs up that concern:

…I combed through his Google Scholar entries and dumped all the duplicates, I ignored all the magazine and newspaper articles (e.g., you can’t count opinion editorials in The Wall Street Journal as evidence of an academic track record), I cut out all non-articles (things Lomborg hadn’t actually written), omitted any website diatribes (e.g., blog posts and the like) and calculated his citation profile.

Based on my analysis, Lomborg’s Google Scholar h-index is 4 for his peer-reviewed articles. If I was being particularly generous and included all of Lomborg’s books, which have by far the most citations, then his h-index climbs to 9. However, none of his books is peer-reviewed, and in the case of his most infamous book, The Skeptical Environmentalist, it has been entirely discredited. As such, any reasonable academic selection committee would omit any metrics based on opinion-based books.

So, the best-case scenario is that Lomborg’s h-index is no more than 4. Given his appointment to Level D (Associate Professor) at a world-class university, the suggestion that he earned it on academic merit is not only laughable, it’s completely fraudulent. There is no way that his academic credentials had anything to do with the appointment.

Even a fresh-out-of-the-PhD postdoc with an h-index of only 3 or 4 would have trouble finding a job. As a rule of thumb, the h-index of a Level D appointment should be in the 20–30 range (this would vary among disciplines). Despite this variation, Lomborg’s h-index is so far off the mark that even accounting for uncertainty and difference of opinion, it’s nowhere near a senior academic appointment.

The other problem people see with Lomborg’s efforts is the sense that the Copenhagen Institute is a bit of a sham, and that Lomborg is not selling informed expertise, but rather, snake oil. From a recent analysis of the status of the Copenhagen Consensus Center:

Copenhagen Consensus Center is a textbook example of what the IRS calls a “foreign conduit” and it frowns strongly on such things. It may also frown on governance and money flows like this…

CCCMoney2

…more than 60% went directly to Lomborg, travel and $853K promotion of his movie. According to Wikipedia it grossed $63K…

Even in a simple US charity, poor governance and obvious conflicts of interest are troublesome, but the foreign element invokes stringent extra rules. Legitimate US charities can send money to foreign charities, but from personal experience, even clearly reasonable cases like foreign universities require careful handling. It is unclear that Lomborg himself is a legitimate charity anywhere, but most of the money seems under his control. One might also wonder where income taxes are paid.

CCC seems to break many rules. Foreign citizen Lomborg is simultaneously CCC founder, president, and highest-paid employee. Most people are a little more subtle when trying to create conduits…

This is apparently the Copenhagen Consensus Center, Copenhagen Consensus Center USA, 262 Middlesex St, Lowell MA .
This is apparently the Copenhagen Consensus Center, Copenhagen Consensus Center USA, 262 Middlesex St, Lowell MA .
Both the flow of money and sources matter when thinking about a non profit research or policy institution. From DeSmog Blog:

A billionaire “vulture capitalist” and major backer of the US Republican Party is a major funder of the think tank of Danish climate science contrarian and fossil fuels advocate Bjørn Lomborg, DeSmogBlog has found.

New York-based hedge fund manager Paul Singer’s charitable foundation gave $200,000 to Lomborg’s Copenhagen Consensus Center (CCC) in 2013, latest US tax disclosures reveal.

That was about a third of the CCC’s donations for the year 2013.

Lomborg, who claims to not be a climate skeptic, is the author of “The Skeptical Environmentalist” and the book and movie “Cool It”

Global Surface Temperatures Continue To Rise

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Global warming is typically measured at the surface, with data from thermometers all across the land areas and sea surface temperatures combined. That isn’t the whole story, of course. Much of the added heat, an effect of human generated greenhouse gas pollution, goes into the upper 2,000 meters or so of the ocean. But we use the surface measurements to track global warming because we have the data for a long period of time, and those data in turn have been linked to longer running but less precise paleo data.

Almost every month for way over a year now has been warm, and April 2015 is no exception. The official NASA GISS surface temperature data is out for the month. April came in at an anomaly value of 75. That’s 0.75 degrees C above the base period for that data set.

That makes April the fifteenth warmest month in the database, which starts in 1880. March was warmer (fifth) and I’m pretty sure May is going to be warmer too (maybe as warm as March, we’ll see).

If we start in April and work backwards 12 months, we can get a one year long average. And, we can go back to the beginning of the data set to look at a 12-month running average for the entire thing. When we do that, we see that the current 12 month period, the one just ending, was the warmest ever in the data set, which makes it likely the warmest one year period in thousands and thousands of years. We have had several record breaking 12-month periods in a row. Here’s what that looks like:

GlobalSurfaceTemperature12-MonthMovingAverage_2015_April

Another way of looking at this is for the calendar year only. This is a graph of the average temperature for the first four months of the year for the entire NASA GISS data set, to give you an idea of where our Year-To-Date stands:

GlobalWarming_AverageTemperature_Jan-April

Will 2015 end up being a very warm year? Almost certainly. Unlike last year, we will see significant enhancements of surface heat from El Nino. This is probably already happening. Using only the year to date data to estimate 2015, it is a good sight warmer than any other calendar year on record. As noted, May will be warm (over 0.80) and subsequent months are likely to be even warmer if El Nino does pan out.

The following graphic indicates where the remaining months of the year will have to fall (on or above the horizontal red line) for 2015 to break the record set by 2014.

2014vs2015_How-much-warmer

Bjorn Lomborg Pulled From Australian Consensus Centre Project

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Over the last several weeks we’ve seen the University of Western Australia accept a $4 million dollar Federal grant to develop a “Consensus Centre” in the mold of Bjorn Lomborg’s non profit, with Lomborg as a key player. Lomborg has been heavily criticized for his lack of scholarship and seemingly biased policy related to climate change and related issues. There was heavy opposition in the Australian academic community to this project. Under pressure from peers and colleagues, Vice Chancellor Paul Johnson has announced that the project is cancelled. In a message published on the UWA University News site, the Vice-Chancellor notes:

The mail drop in Massachusetts which apparently fronts for Lomborg's Copenhagen Consensus Institute.
The mail drop in Massachusetts which apparently fronts for Lomborg’s Copenhagen Consensus Institute.

… it is with great regret and disappointment that I have formed the view that the events of the past few weeks places the Centre in an untenable position as it lacks the support needed across the University and the broader academic community to meet its contractual obligations and deliver value for money for Australian taxpayers.
…
I have today spoken to the Federal Government and Bjorn Lomborg advising them of the barriers that currently exist to the creation of the Centre and the University’s decision to cancel the contract and return the money to the government.

More here: University of Western Australia Cancels $4 Million Federal Government Contract For Bjorn Lomborg’s Consensus Center

The #FauxPause is Faux

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The Earth’s climate is warming. The upper oceans are warming, the sea surface temperatures are elevated, the air in the lower Troposphere, where we live, is warming. This warming is caused almost entirely by the increase in human generated greenhouse gasses and the positive (not positive in a good way) feedbacks caused by that. The effects that increase the global heat imbalance and the effects that decrease it (such as greenhouse gas increase and aerosols — dust — from volcanoes, respectively) vary over time in their effect, which causes some variation in the upward march of global surface and ocean temperatures. Meanwhile heat is going back and forth between the surface (atmosphere and sea surface) and the deeper (but still upper) ocean, which causes either of these parts of the Earth system to wiggle up and down in temperature. There are other effects causing other wiggles.

See: The Ocean Is The Dog. Atmospheric Temperature Is The Tail

Every now and then the wiggling results in a seemingly rapid increase in temperature. Every now and then the wiggling results in a seeming slowdown in increase in temperature. When the latter happen, those who wish you to believe that climate change is not real point, jumping up and down, giddy, and say, “See, there is a pause in global warming, therefore global warming is not happening!” They are wrong for the reasons just stated.

Dana Nuccitelli (author of this book), over at the Guardian, has written a blog post that nicely summarizes current scientific thinking on the so-called pause (or so-called hiatus) which has been named by witty climate scientists as the #FauxPause. Because it is faux.

Screen Shot 2015-05-06 at 10.42.10 AM

The post is here, go read it: Pause needed in global warming optimism, new research shows

I’m pretty sure Dana and I were looking at the same information recently. While Dana focuses on the #FauxPause, I recently penned this: Global Warming Getting Worse

Global Warming Is Happening: DENIAL101.x

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I’m auditing the EdEx course “Denial101x: Making Sense of Climate Science Denial.” This is Week 2: Global Warming ins Happening. The course is covering indicators of warming, what is happening in the Cryosphere, and related matters.

Here is an example lecture segment:

A central theme of this week is the relationship between climate and weather, and how this relationship becomes fodder for the development of myths in service of denial about climate change. The climate is a cherry orchard. Weather is the cherries. Don’t pick the cherries!

There are many dimensions the climate system that allow cherry picking. You can look at local temperature records and see very little warming in some placs. You can look at different levels of the atmosphere, and you can ignore the oceans. Don’t ignore the oceans, that is where most of the heat imbalance caused by anthropogenic greenhouse gas pollution plays out.

At one point in this week’s course, you get to play with a really cool data tool. Like this:

Screen Shot 2015-05-05 at 8.54.34 AM

Playing around with that tool is very fun and informative, and the process is backed up with some excellent information about how the data set(s) work(s).

Notes:

Cherry Picking, Setting False Expectations, How records are made and tracked (we are setting hot records more often than cold records over recent decades, in the US and elsewhere). Global warming is analogous to rigging the climate dice.

Sea level rise, thermal expansion of the global ocean, melting glacial ice. Glaciers are losing about 150 billion tonnes of ice a year, accelerating. Many mountain glaciers have disappeared or shrunk a great deal. Annual mass balance. Tracking glacier history. Myth: Some glaciers are growing therefore there is no global warming (cherry picking, there are a few growing glaciers due to warming causing more snow locally).

Greenland ice loss: Over 300 billion tonnes per year, or 6 meters of ocean if all melted. Moulins. Ice shelves as corks. Gaining ice in interior. Greenland is already at 2 degrees C surface air increase. Largest individual contributor to sea level rise. Myth: Since ice is building up in the interior (ignoring the rest of the region) global warming is not real. Note: Most of the accelerated melt is very recent, mass balance has been negative for about 15 years, and this is increasing. Get waders.

Antarctica, west and east (largest, oldest). Total contribution to global sea level if all melted = 72 meters. Recently discovered that WAIS is more sensitive to climate change than previously thought. Melt started in recent decades and is accelerating, in WAIS. EAIS relatively stable. (But this is questionable, may be changing.)

Antarctic sea ice: Seasonal, does not influence climate much. Myth: sea ice increase means global warming not real. Winds may blow sea ice outwards, so open water freezes, and the winds blow colder water. Fresh meltwaters easier to freeze. Snow fall increased.

Land and sea ice are totally different things. Myth of sea ice discounting global warming is cherry picking and error of omission.

Excellent in depth interview with several ice experts. It is worth looking at these longer interviews even if they are not on the quiz!

Building the temperature record (How do we measure global warming). Myths: Thermometers not reliable, insufficient in number. Jumping to conclusions … scientists estimate error, the error is way smaller in magnitude than the temperature increase signal. Multiple methods of measurement agree with each other.

Urban heat island effect. Neat: Compare light pollution with heat island effect. They don’t match up, suggesting HIE is very local and not strong. NASA matching of paired rural/urban stations: effect is small. Other studies support this. Fallacy: Jumping to conclusions. Going from a reasonable hypothesis to the conclusion, meanwhile actual scientists examined the hypothesis and found it wanting. Myth: “Corrections” are bogus (jumping to conclusions). Truth: Corrections are proper adjustments to data. Ie when you change instruments or move instruments an adjustment or calibration may be necessary. Comparing adjusted vs. non adjusted data shows that the adjustments, while justified, don’t change the numbers much.

Wavy Jet Streams. How hey work. Myth: “It’s cold out, so much for global warming!” Cherry Picking, that. GLOBAL warming.

How jet streams form and why they get wavy. Arctic amplification (positive feedback from ice/snow cover changes, etc.). So tropical/polar temp gradient (and thus pressure gradient) reduces, waves and slower jet streams result.

“Climate Change” vs. “Global Warming.” Myth: Some bogus story about how scientists are playing a fast one. Personally, I prefer Obamacare over the Affordable Care Act. (FLICC type: Conspiracy Theory. Over Simplification.)

Global Warming: Getting worse

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I recently noted that there are reasons to think that the effects of human caused climate change are coming on faster than previously expected. Since I wrote that (in late January) even more evidence has come along, so I thought it was time for an update.

First a bit of perspective. Scientists have known for a very long time that the proportion of greenhouse gasses in the Earth’s atmosphere controls (along with other factors) overall surface and upper ocean heat balance. In particular, is has been understood that the release of fossil Carbon (in coal and petroleum) as CO2 would likely warm the Earth and change climate. The basic physics to understand and predict this have been in place for much longer than the vast majority of global warming that has actually happened. Unfortunately, a number of factors have slowed down the policy response, and the acceptance of this basic science by non scientists.

A very small factor, often cited by climate contrarians, is the consideration mainly during the 1960s and 1970s, that the Earth goes through major climate swings including the onset of ice ages, so we have to worry about both cooling and warming. This possibility was obviated around the time it was being discussed, though people then may not have fully realized it at the time, because as atmospheric CO2 concentrations increased beyond about 300ppm, from the pre-industrial average of around 250–280ppm (it is now at 400ppm), the possibility of a new Ice Age diminished to about zero. Another factor mitigating against urgency is the fact that the Earth’s surface temperatures have undergone a handful of “pauses” as the surface temperature has marched generally upwards. I’m not talking about the “Faux Pause” said to have happened during the last two decades, but earlier pauses, including one around the 1940s that was probably just a natural down swing that happened when there was not enough warming to swamp it. A second pause, shorter, happened after the eruption of Mount Pinatubo, in 1991.

Prior to recent anthropogenic global warming, the Earth’s surface temperature has squiggled up and down do to natural variability. Some of these squiggles were, at least reionally large enough to get names, such as the “Medieval Warm Period” (properly called the “Medieval Climate Anomaly”) and the “Little Ice Age.” When the planet’s temperature started going distinctly up at the beginning of the 20th century, these natural ups and downs, some larger and some smaller, caused by a number of different factors, eventually became imposed on a stronger upward signal. So, when we have a “downward” swing caused by natural variation, it is manifest not so much as a true downturn in surface temperatures, but rather, less of an upward swing. Since about a year and a half ago, we have seen very steady warming suggesting that a recent attenuation in how much temperatures go up is reversing. Most informed climate scientists expect 2015 and even 2016 to be years with many very warm months globally. So, the second factor (the first being the concern over the ice age as possibly) is natural variation in the Earth’s surface temperature. To reiterate, early natural swings in the surface temperature may have legitimately caused some scientists to wonder about how much greenhouse gas pollution changes things, but later natural variations have not; Scientists know that this natural variation is superimposed on an impressive long term upward increase in temperature of the Earth’s surface and the upper ocean. Which brings us to the third major factor delaying both non-scientists’ acceptance of the realities of global warming, and dangerous policy inaction: Denialism.

The recent relative attenuation of increase in surface temperatures, likely soon to be over, was not thought of by scientists as disproving climate models or suggesting a stoppage of warming. But it was claimed by those denying the science as evidence that global warming is not real and that the climate scientists have it all wrong. That is only one form of denialism, which also includes the idea that yes, warming is happening, but does not matter, or yes, it matters, but we can’t do anything about it, or yes, we could do something about it, but the Chinese will not act (there is little evidence of that by the way, they are acting) so we’re screwed anyway. Etc.

The slowdown in global warming is not real, but a decades-long slowdown in addressing global warming at the individual, corporate or business, and governmental levels is very real, and very meaningful. There is no doubt that had we started to act aggressively, say, back in the 1980s when any major hurdles for overall understanding of the reality of global warming were overcome, that we would be way ahead of where we are now in the effort to keep the Carbon in the ground by using clean energy. The precipitous drop we’ve seen in photovoltaic costs, increases in battery efficiency and drop in cost, the deployment of wind turbines, and so on, would have had a different history than they have in fact had, and almost certainly all of this would have occurred faster. Over the last 30 or 40 years we have spent considerable effort building new sources of energy, most of which have used fossil Carbon. If even half of that effort was spent on increasing efficiency and developing non fossil Carbon sources, we would not have reached an atmospheric concentration of CO2 of 400ppm in 2015. The effects of greenhouse gas pollution would be less today and we would not be heading so quickly towards certain disaster. Shame on the denialists for causing this to happen.

I should mention a fourth cause of inappropriate rejection of the science of climate change. This is actually an indirect effect of climate change itself. You all know about the Inhofe Snowball. A US Senator actually carried a snowball into the senate chamber, a snowball he said he made outside where there has been an atypical snowfall in Washington DC, and held it aloft as evidence that the scientists had it all wrong, and that global warming is a hoax. Over the last few years, we have seen a climatological pattern in the US which has kept winter snows away from the mountains of California, contributing significantly to a major drought there. The same climatological phenomenon has brought unusual winter storms to states along the Eastern Seaboard that usually get less snow (such as major snow storms in Atlanta two winters ago) and persistent unseasonal cold to the northeastern part of the US. This change in pattern is due to a shift in the behavior of the Polar jet stream, which in turn is almost certainly caused by anomalous very warm water in parts of the Pacific and the extreme amplification of anomalous warm conditions in the Arctic, relative to the rest of the planet. (The jury is still out as to the exact process, but no serious climate scientists working on this scientific problem, as far as I know, doubts it is an effect of greenhouse gas pollution). This blob of cold air resting over the seat of power of one of the more influential governments in the world fuels the absurd but apparently effective anti-science pro-fossil fuel activism among so many of our current elected officials.

Climate Sensitivity Is Not Low

The concept of “Climate Sensitivity” is embodied in two formulations that each address the same basic question: given an increase in CO2 in the atmosphere, how much will the Earth’s surface and upper ocean temperatures increase? The issue is more complex than I’ll address here, but here is the simple version. Often, “Climate sensitivity” is the amount of warming that will result from a doubling of atmospheric CO2 from pre-industrial levels. That increase in temperature would take a while to happen because of the way climate works. On a different planet, equilibrium would be reached faster or slower. Historically, the range of climate sensitivity values has run from as low as about 1.5 degrees C up to 6 degrees C.

The difficulty in estimating climate sensitivity is in the feedbacks, such as ice melt, changes in water vapor, etc. For the most part, feedbacks will increase temperature. Without feedbacks, climate sensitivity would be about 1.2 degrees C, but the feedbacks are strong, the climate system is complex, and the math is a bit higher level.

As time goes by, our understanding of climate sensitivity has become more refined, and it is probably true that most climate scientists who study this would settle on 3 degrees C as the best estimate, but with wide range around that. The lower end of the range, however, is not as great as the larger end of the range, and the upper end of the range probably has what is called a “fat tail.” This would mean that while 3 degrees C is the best guess, the probability of it being way higher, like 4 or 5, is perhaps one in ten. (This all depends on which model or scientist you query.) The point here is that while it might be 3, there is a non-trivial chance (one in ten is not small for an extreme event) that it would be a value that would be really bad for us.

Anyway, Dana Nuccitelli has a recent post in The Guardian that looks at climate sensitivity in relation to “The Single Study Syndrome.”

There have been a few recent studies using what’s called an “energy balance model” approach, combining simple climate models with recent observational data, concluding that climate sensitivity is on the low end of IPCC estimates. However, subsequent research has identified some potentially serious flaws in this approach.

These types of studies have nevertheless been the focus of disproportionate attention. For example, in recent testimony before the US House of Representatives Committee on Science, Space and Technology, contrarian climate scientist Judith Curry said,

Recent data and research supports the importance of natural climate variability and calls into question the conclusion that humans are the dominant cause of recent climate change: … Reduced estimates of the sensitivity of climate to carbon dioxide

Curry referenced just one paper (using the energy balance model approach) to support that argument – the very definition of single study syndrome …

…As Andrew Dessler told me,

There certainly is some evidence that climate sensitivity may be below 2°C. But if you look at all of the evidence, it’s hard to reconcile with such a low climate sensitivity. I think our best estimate is still around 3°C for doubled CO2.

So there is not new information suggesting a higher climate sensitivity, or a quicker realization of it, but there is a continuation of the consensus that the value is not low, despite efforts by so called luke-warmists or denialists to throw cold water on this hot topic.

Important Carbon Sink May Be Limited.

A study just out in Nature Geoscience suggests that one of the possible factors that may mitigate against global warming, the terrestrial sink, is limited in its ability to do so. The idea here is that as CO2 increases some biological activities at the Earth’s Surface increase and store some of the carbon in solid form as biomass. Essentially, the CO2 acts as plant fertilizer, and some of that Carbon is trapped in the detritus of that system, or in living tissue. This recent study suggests that this sink is smaller than previously suspected.

Terrestrial carbon storage is dependent on the availability of nitrogen for plant growth… Widespread phosphorus limitation in terrestrial ecosystems may also strongly regulate the global carbon cycle… Here we use global state-of-the-art coupled carbon–climate model projections of terrestrial net primary productivity and carbon storage from 1860–2100; estimates of annual new nutrient inputs from deposition, nitrogen fixation, and weathering; and estimates of carbon allocation and stoichiometry to evaluate how simulated CO2 fertilization effects could be constrained by nutrient availability. We find that the nutrients required for the projected increases in net primary productivity greatly exceed estimated nutrient supply rates, suggesting that projected productivity increases may be unrealistically high. … We conclude that potential effects of nutrient limitation must be considered in estimates of the terrestrial carbon sink strength through the twenty-first century.

Related, the Amazon carbon sink is also showing long term decline in its effectiveness.

Permafrost Feedback

From Andy Skuce writing at Skeptical Science:

We have good reason to be concerned about the potential for nasty climate feedbacks from thawing permafrost in the Arctic….research bring good news or bad? [From recent work on this topic we may conclude that] although the permafrost feedback is unlikely to cause abrupt climate change in the near future, the feedback is going to make climate change worse over the second half of this century and beyond. The emissions quantities are still uncertain, but the central estimate would be like adding an additional country with the unmitigated emissions the current size of the United States’ for at least the rest of the century. This will not cause a climate catastrophe by itself, but it will make preventing dangerous climate change that much more difficult. As if it wasn’t hard enough already.

Expect More Extreme Weather

Michael D. Lemonick at Climate Central writes:

disasters were happening long before humans started pumping heat-trapping greenhouse gases into the atmosphere, but global warming has tipped the odds in their favor. A devastating heat wave like the one that killed 35,000 people in Europe in 2003, for example, is now more than 10 times more likely than it used to be…. But that’s just a single event in a single place, which doesn’t say much about the world as a whole. A new analysis in Nature Climate Change, however, takes a much broader view. About 18 percent of heavy precipitation events worldwide and 75 percent of hot temperature extremes — defined as events that come only once in every thousand days, on average — can already be attributed to human activity, says the study. And as the world continues to warm, the frequency of those events is expected to double by 2100.

Melting Glaciers Are Melting

This topic would require an entire blog post in itself. I’ll give just an overview here. Over the last year or so, scientists have realized that more of the Antarctic glaciers are melting more than previously thought, and a few big chunks of ice have actually floated away or become less stable. There is more fresh water flowing from glacial melt into the Gulf of Alaska than previously thought. Related to this, as well as changes in currents and increasing sea temperatures, sea level rise is sparking sharply.

The Shifting Climate

I mentioned earlier that the general upward trend of surface temperature has a certain amount of natural variation superimposed over it. Recent work strongly suggests that a multi-decade long variation, an up and down squiggle, which has been mostly in the down phase over recent years, is about to turn into an upward squiggle. This is a pretty convincing study that underscored the currently observed month by month warming, which has been going on for over a year now. It is not clear that the current acceleration in warming is the beginning of this long term change … that will be known only after a few years has gone by. But it is important to remember that nothing new has to happen, no new scientific finding has to occur, for us to understand right now that the upward march of global surface temperatures is going to be greater on average than the last decade or so has suggested. We have been warming all along, but lately much of that warming has been in the oceans. Expect surface temperatures to catch up soon.

Dire Predictions: Understanding Climate Change, Must Read Book

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Dire Predictions: Understanding Global Warming by Michael Mann and Lee Kump is everyperson’s guide to the latest Intergovernmental Panel on Climate Change (IPCC) report. The IPCC issues a periodic set of reports on the state of global climate change, and has been doing so for almost two decades. It is a massive undertaking and few have the time or training to read though and absorb it, yet it is very important that every citizen understands the reports’ implications. Why? Because human caused climate change has emerged as the number one existential issue of the day, and individuals, corporations, and governments must act to implement sensible and workable changes in behavior and policy or there will be dire consequences.

Dire Predictions is a DK Publishing product, which means it is very visual, succinct, and as is the case with all the DK products I’ve seen, well done. This is the second edition of the book, updated to reflect the most recent IPCC findings. The book gives a basic background on climate change, describes scientific projections and how they are developed, discuses impacts of climate change, and outlines vulnerability and modes of adaptation to change. The book finishes with a panoply of suggestions for solving the climate change crisis. Since Dire Predictions reflects the IPCC reports, it can be used as a primer in understanding the much more extensive and intensive original document, but it can also be used entirely on its own. I would recommend Dire Predictions for use in any of a wide range of classroom settings. It could be a primary text in middle school or high school Earth Systems classes, or a supplementary text in intro college courses. Anyone who is engaged in the climate change conversation and wants to be well informed simply needs to get this book, read it, and have it handy as a reference.

See: An interview with Michael Mann by yours truly

Lee Kump is a professor in Geosciences at Penn State, and author of a major textbook “The Earth System.” Michael Mann is Distinguished Professor of Meteorology and Director of the Earth System Science Centre at Penn State, and author of The Hockey Stick and the Climate Wars: Dispatches from the Front Lines (as well as countless scientific publications). Mann has been on top of the climate change issue for years. His work in the late 1980s, with colleagues, produced the famous “Hockey Stick” graph which had two major impacts. First, it made the link between the recent century or so of direct observation of Earth’s surface temperatures (with thermometers and/or satellites) and the “paleo” record made up of proxyindicators of temperature, an essential step in placing modern climate change in long term perspective. Second, using this connection, Mann and colleagues showed that recent global warming, known to be primarily caused by human released greenhouse gas pollution, was already extreme and likely to get more extreme. Since then, Mann has been a key scientist involved with the IPCC, and has carried out many important research projects.

See: New Research on Tree Rings as Indicators of Past Climate

I asked Dr. Mann to address a handful of questions I had about Dire Predictions.

Question: Some might think of the title of the book as a bit extreme, even “alarmist,” to reference a term we often see used by climate science deniers. I assume you chose it carefully. Why “Dire Predictions: [subtitle]” instead of “Understanding Climate Change: [subtitle]”?

Answer: This was a mutual decision between the authors (Lee Kump and myself) and the publisher. The publisher felt this title both communicates the nature of the content of the book and the larger message of urgency; The predictions really are “dire” for the worst case scenarios, i.e. if we fail to act on climate change.

Question: What are the biggest changes, or perhaps most interesting changes, between the first and second edition, such as new research? Did any of the initial projections get less dire? More dire?

Answer: The main difference is that the book reflects the latest science as reported in the most recent (5th) IPCC assessment report. Some spreads remained unchanged, i.e. we felt there were no significant developments in the science since the last report (and last book). But in other cases, there were some substantial developments, i.e. we felt compelled to talk about the “Faux Pause” since it has gotten so much attention, and the issue of equilibrium climate sensitivity is discussed in more depth. The concept of the “Anthropocene” is dealt with more explicitly. And the issue of recent cold eastern U.S. winters and what it really means, and the unprecedented current drought in California are discussed.

Question: It seems that for decades the climate science has been settled sufficiently to realize that release of fossil Carbon will have serious consequences. Yet policy and technology changes to address this have been slow. Is this simply because such things take a long time, or have the efforts of science deniers been successful in slowing down action? How much better (or less dire) would things be in, say, 2050 had people, corporations, and governments accepted climate change as a serious matter 20 years ago? In other words, how much damage has science denialism done?

Answer: Oh, that’s a fundamentally important point. There is a huge “procrastination penalty” in not acting on the problem, and we’ve presumably committed to billions if not trillions of economic losses by not having acted yet. But there is still time to avert the worst and most costly damages, so there is an urgency of action unlike there has ever been before. This is something we tackle head on in the book.

See: Michael Mann Answers Questions From Dangerous Children About Ian Somerhalder

Question: Since you finished working on the second edition, are there any new research findings you wish you could somehow add to the book? Or, any changes in what is emphasized?

Indeed. As you know, Stefan Rahmstorf, I and others recently published an article in Nature Climate Change demonstrating that the AMOC (North Atlantic ocean circulation, the so-called “conveyor belt”) may be weakening even faster than the IPCC models indicate. Yet, we have downplayed that topic (though it is mentioned in a brand new spread on “Tipping Points”) because the consensus has leaned toward this being one of the less likely tipping points to occur in the decades ahead. This is a reminder that science is often fast-moving, and in this case, had we waited a year to publish the 2nd edition of DP, we might have chosen to actually give the AMOC collapse issue even more attention!

See: A list of climate change books

Question: I’m wondering if the projections for sea level rise in Dire Predictions are conservative with respect to more recent research. Also, there seems to be a more clear and explicit link between climate change an ware or social unrest. Would these issues also have more attention if you had another shot at the book?

Answer: We do discuss the sea level rise and the fact that iPCC projections here (and for many other variables) have been historically too conservative. There is some discussion now about the role of water resources in national security and conflict, and the huge advances that are taking place in renewable energy (that is something that has changed dramatically since the first edition—and a reminder of the reasons there are for cautious optimism).

Also of interest:

Comparing models and empirical estimates Part II: interview with Brown

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I recently posted an overview of a new climate study, Comparing the model-simulated global warming signal to observations using empirical estimates of unforced noise, by Patrick T. Brown, Wenhong Li, Eugene C. Cordero & Steven A. Mauget. That study is potentially important because of what it says about how to interpret the available data on global warming caused by human generated greenhouse gas pollution. Also, the since publication the study has been rather abused by climate contrarians who chose to interpret it very inaccurately. This is addressed in this item by Media Matters.

My post on the paper describes the basic findings, but at the time I wrote that, I had a number of questions for the study authors. I sent the questions off noting that there was not a big hurry to get back to me, since the climate wasn’t going anywhere any time soon. Lead Author, Patrick Brown, in the mean time, underwent something of a trial by fire when the denialosphere went nuts in the effort to misinterpret the study’s results. I guess I can’t blame them. There is no actual science to grab on to in the effort to deny the reality or importance of anthropogenic climate change, so why not just make stuff up?

Anyway, Patrick Brown addressed all the questions I sent him, and I thought the best way to present this information is as a straight forward interview. As follows.

Amidst the reactions I’ve seen on social media, blogs, etc. to your paper, I see the idea that your study suggests a downward shift in the (severity of, literally, GMT) resulting from greenhouse gas pollution than what was previously thought. However, I don’t think your paper actually says that. Can you comment?

Reply: You are correct, our paper does not say that. How much warming you get for a given change in greenhouse gasses is termed ‘climate sensitivity’ and our study does not address climate sensitivity at all. In fact, the words ‘climate sensitivity’ do not even appear in the study so we are a little frustrated with this interpretation.

It seems to me that between RCP 4.5, 6 and 8.5, you are suggesting that they differ in their ability to predict, with 6 being the best, 4.5 not as good (but well within the range) and 8.5 as being least good, possible but depending on conditions maybe rejectable.

Reply: Yes and this is just over the recent couple decades, our study does not address how likely these scenarios will be by next year or 2050 or 2100.

At this point I think the following characterizes your work; 1) Taking a somewhat novel look at models and data, what we were thinking before seems by and large confirmed by your work; The central trend of warming with increased greenhouse gas is confirmed in that models and data are by and large aligned in both central tendency (the trend line) and variation. Is this correct?

Reply: We found that models largely get the ‘big picture’ correct when it comes to how large the natural chaotic variability is. We already knew the multi-model mean was not getting the trend correct over the past decade-or-so but we knew that this could have been due to random natural variation. Our study just quantified how large the underlying global warming progression could be given that we saw little warming over the recent past.

Your paper seems to confirm that the more likely scenarios are more likely and the less likely scenarios are as previously thought, possible but less likely. More extreme scenarios have not been taken off the table, though there may be refinement in how we view them. Is that a fair characterization?

Reply: Yes.

The amount of noise in the climate system (EUN) is sufficiently high that much of the observed squiggling around a central trend line is accounted for by that noise and does not require questioning the models (that is my rewrite of "We find that the empirical EUN is wide enough so that the interdecadal variability in the rate of global warming over the 20th century does not necessarily require corresponding variability in the rate-of-increase of the forced signal” in your paper) Is it correct to say that unforced squiggling/EUN/noise would naturally go away with longer sampling intervals (going from years to decades, for example) but these results suggest that even interdecadal variability is likely a result of noise, not forcing.

Reply: Yes, we do not rule out that forcing may be responsible but we are saying that this inderdecadal variability doesn’t necessarily require forcing.

Would it be accurate to say that your paper speaks mainly to the nature of variation observed temperature over time, the squiggling of the signal up and down along a trend line, in relation to variation that is seen in models?

Reply: Just to clarify, in the paper we refer to the component of GMT change that is due to external radiative forcings (e.g., greenhouse gasses) as the ‘signal’ and the component due to chaotic unforced variability as ‘noise’. We don’t necessarily expect either of these to be linear or to follow a trend line. We estimated how large the noise was and used this estimate to see what we might be able to infer regarding the underlying signal, given recent observations.

Noise in this signal is presumably dampened by averaging out the numbers over time (widening the sampling interval, if you will) so as we go from years to decades we get a straighter line that should be more in accord with the correct model. Your paper seems to be suggesting that natural/internal variation (EUN, noise) often operates at a scale larger than we would dampen by looking at the data at the decade-long scale. Is that correct? If so, is it the case that an excursion (such as the so called pause/hiatus) that is 10–20 years long does not fall out of the range of expectations (of noise effects) according to your work?

Reply: Yes. No recent trend was completely outside of the range of possibility – even for RCP8.5. However, it’s naturally the case that a steeper signal (like RCP8.5) is less likely than a slower progressing signal (like RCP6.0) over a time period of no warming.

There seems to be some confusion about your conclusions regarding RCP8.5. Does this paper suggest that RCP8.5 should be rejected? Or does it suggest that it is less likely than previous work suggests?

Reply: First it must be said that we were not looking at how likely RCP8.5 is in the long run. We are simply asking the question “if it hasn’t warmed in 11 years (2001–2013) how likely is it that we have been on RCP 8.5 during that time? We find that it is not very likely but still possible.

Asking this a slightly different way (to address the confusion that is out there) does your paper confirm that 8.5 is less likely than RCP 6.0 as previously thought? If RCP 8.5 is less likely than previously thought does this mean that the entire probability distribution estimate for climate sensitivity needs to be shifted downward, or, alternatively, does it only mean that the upper tail is less fat than previously thought, and if so, how much less fat?

Reply: We may have seen less warming than RCP8.5 because the forcings have been overestimated in RCP8.5 relative to reality over the past decade. If forcings have been overestimed than we expect less warming, even with high climate sensitivity. Because of this possibility, our study cannot make conclusions about the climate sensitivity distribution.

Schurer et al did something similar to what you’ve done here a couple of years ago. Comparing their work and yours the question arises, can you get adequate constraint on the forced and internal variability separately from the paleodata and paleo-forced simulations? Or is there too much noise in the two systems that differencing between two noisy data sets is affected by too much noise amplification? In other words, you have partitioned the problem into model outputs vs. empirical, while Shurer separate between forced and internal. Does your (relatively orthogonal) take an additional risk?

Reply: It is certainly a challenge to know how much can be inferred from the paleo record. Our goal, however, was simply to use the paleo-record in a sensible way to estimate the magnitude of unforced variability. We feel that we adequately account for uncertainty in this estimation as we came up with over 15,000 different estimates which sampled uncertainty in different parameters.

Finally, your study goes up to 2013. The year 2013 (or thereabouts) may be considered as part of a sequence of years with little increase in surface temperature. However, starting in March 2014 we have seen only very warm months (starting earlier than that, but excluding February). Predictions on the table suggest 2015 will be warm, and actually, 2016 as well. If it turns out that 2014, 2015, and 2016 are each warmer than the previous year, and your entire study was redone to go to the end of 2016, would your results change? If so, how? (I?m thinking not because the time scale of your work is so large, but I need to ask!)

Reply: The study was submitted before the 2014 datpoint was added to the record which is why it stops there. If by 2016, we are back in the middle of the distribution for RCP8.5 then it would imply that we might be back on the RCP8.5 scenario. This wouldn’t actually change the results of the study since the study was only concerned with what had already occurred. New data will not change that it did not warm from 2002–2013 so our probability calculations of how likely it was that we are on RCP8.5 over those 11 years would not change.

What is scientific consensus?

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A group of scientists attending a major conference get together in a bar. They talk, but they agree on nothing because they are critical academics. The server comes along to take the beer order and says, “I noticed you all are constantly arguing. What are you arguing about?”

“Sensitivity,” one of them says. “It is the number of degrees C the Earth’s surface will warm with a doubling of CO2 in the atmosphere. Is it 2, 3, 4? … We cant settle on a number”

The server considers their plight for a moment. Suddenly, she rips several sheets out of her order book and hands one to each of the scientists. She notices they all already have pens and mechanical pencils in their shirt pockets.

“Each of you write down a number for sensitivity. Don’t share. I’ll look at them all and if they are all the same number I’ll bring you your beer for free for the rest of the evening.”

The scientists comply. She looks at their numbers. They are all the same. Despite the quibbling they all had the same sense for what the number for climate “sensitivity” likely is. They get free beer for the evening.

Scientific consensus is what most scientists will nitpick about but ultimately agree on if free beer is at stake.

My first homework assignment for Making Sense of Climate Denial.

Will 2015 be warmer than 2014?

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That is a good question, and difficult to answer. If it turns out to be, it will be the warmest calendar year in the instrumental record, which goes back into the 19th century.

Regardless of what El Nino (ENSO) does, 2015 will be a warm year. Why? Because everything is warm and getting warmer and even if 2015 is less warm than 2014, it will be warm. There is no other possibility.

Even without the effects of El Nino, though, it is possible that 2015 will be warmer than 2014 because we see a lot of heat out there. If the present, relatively weak El Nino continues for a while, it will likely increase the chance that 2015 will be warmer than 2014. But current predictions suggest that 2014 will not only continue to have a strengthening El Nino, but El Nino conditions may either continue or repeat over 2015 and beyond. If that happens, not only is 2015 likely to be the warmest year in the instrumental record (since 1880) but 2016 may be in the running to be even warmer.

So far each month of 2015 has been very warm (see graph above) overall (the “zero” on the Y-axis of that graph represents the 20th century mean surface temperature). This month, April, is not excessively warm. Likely when April is plotted for 2015 on this graph, it will be either cooler then or around the same as last April.

Obviously we won’t know until the year is over, and given that climate change is a medium term phenomenon best measured in decades, we shouldn’t be in such a hurry to know these numbers. But, given that climate change is the existential issue of our day and the data become available month by month, we are not going to ignore the march of surface temperatures. We are going to, rather justifiably, be interested in what happens, month by month, as it happens.

At the end of the month, climate scientists such as my friend John Abraham, who is tracking global temperatures daily, will be able to produce a very good estimate of what the major data bases (such as NASA GISS, used here) will say, but those data bases won’t be officially updated until around the middle of the following month or so. So stay tuned.

Added: For those keeping track, I made a new version of the above graph. The red line represent the monthly anomaly values required (on average) for the rest of the year for 2015 to equal 2014. I also extended the Y-axis to 100 because the warmest month in the GISS database is in the 90s, just in case such a very warm month occurs. It is likely that April 2015 will not e as warm as April 2014 but it will likely be above the red line.

Will_2015_be_warmer_than_2014