In 2007, the Intergovernmental Panel on Climate Change published its fourth assessment report, internationally regarded as the most credible summary of climate science to date. It concluded that “most of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations”.

A clear question remains: How much is “most”? 51%? 75%? 99%? At the time that the IPCC report was written, the answer was unclear. However, a new frontier of climate research has emerged since, and scientists are working hard to quantify the answer to this question.

I recently attended the 2011 American Geophysical Union Fall Meeting, a conference of over 20 000 scientists, many of whom study the climate system. This new area of research was a hot topic of discussion at AGU, and a phrase that came up many times was “more than 100%”.

That’s right, humans are probably causing more than 100% of observed global warming. That means that our influences are being offset by natural cooling factors. If we had never started burning fossil fuels, the world would be cooling slightly.

In the long term, oscillations of the Earth’s orbit show that, without human activity, we would be very slowly descending into a new ice age. There are other short-term cooling influences, though. Large volcanic eruptions, such as Mount Pinatubo in 1991, have thrown dust into the upper atmosphere where it blocks a small amount of sunlight. The sun, particularly in the last few years, has been less intense than usual, due to the 11-year sunspot cycle. We have also experienced several strong La Niña events in the Pacific Ocean, which move heat out of the atmosphere and into the ocean.

However, all of these cooling influences pale in comparison to the strength of the human-caused warming influences. The climate change communication project Skeptical Science recently summarized six scientific studies in this graphic:

Most of the studies estimated that humans caused over 100% of the warming since 1950, and all six put the number over 98%. Additionally, most of the studies find natural influences to be in the direction of cooling, and all six show that number to be close to zero.

If you are interested in the methodologies and uncertainty ranges of these six studies, Skeptical Science goes into more detail, and also provides links to the original journal articles.

To summarize, the perception that humans are accelerating a natural process of warming is false. We have created this problem entirely on our own. Luckily, that means we have the power to stop the problem in its tracks. We are in control, and we choose what happens in the future.

• Mountain pine beetles, whose range is expanding due to warmer winters, are beginning to infest jack pines as well as lodgepole pines. To understand the danger from this transition, one only needs to look at the range maps for each species:
  

  Lodgepole Pine

  

  Jack Pine

  A study from Molecular Ecology, published last April, has the details.

• Arctic sea ice extent was either the lowest on record or the second lowest on record, depending on how you collect and analyze the data. Sea ice volume, a much more important metric for climate change, was the lowest on record:

And one piece of good news:

• Our abstract was accepted to AGU! I have been wanting to go to this conference for two years, and now I will get to!

The main problem with the IPCC, in my opinion, is that their reports are out of date as soon as they’re published, and then everyone has to wait another six years or so for the next version, which is subsequently out of date, and so on. Additionally, because there are so many authors, reviewers, and stakeholders involved in the IPCC, the reports come to reflect the lowest-common-denominator scientific understanding, rather than the median opinion of experts. In particular, government officials oversee the writing and reviewing of the Summary for Policymakers, to make sure that it’s relevant and clear. However, some governments are beginning to abuse their power in this process. The late Stephen Schneider, in his 2009 book Science as a Contact Sport, recounts his experiences with government representatives who absolutely refuse to allow certain conclusions to be published in the IPCC, regardless of their scientific backing.

The result is that the IPCC reports frequently underestimate the severity of climate change. For example, in the most recent report, the worst-case estimate of sea level rise by the end of this century was 0.59 m. Since then, scientists have revised this estimate to 1.9 m, but it won’t show up in the report until the next edition comes out around 2014.

Another example concerns Arctic sea ice: the worst-case scenario from the IPCC was an ice-free Arctic in the summer beginning around 2100. These estimates have come down so rapidly that there’s an outside chance the summer sea ice could be gone before the next IPCC report has a chance to correct it (presentation by Dr. David Barber, media coverage available here). It will more likely disappear around 2035, but that’s still a drastic change from what the IPCC said.

Despite this conservative stance, there are still some who think the IPCC is alarmist (this is usually paired with something about a New World Order and/or socialists using a carbon tax to take over the world). Naturally, the IPCC has become a favourite target of climate change deniers, who wish to obscure the reality of human-caused global warming. Last year, they claimed to have found all kinds of errors in the latest report, somehow proving that global warming wasn’t happening. In fact, most of these so-called “errors” were nothing of the sort, and the worst of the two real mistakes in the report involved a typo regarding which year certain glaicers were expected to disappear. Not bad, for a three-thousand-page document, but it created quite the media firestorm. Apparently scientists are expected to have 100% accuracy at all times, or else they are frauds.

Just a few weeks ago, the IPCC made some changes to their policies in response to these events. Their press release about the new policies featured the phrase ”Boost Quality, Transparency and Rigour” in the title.

No, no, no. That’s not what the IPCC needs. These are very admirable goals, but they’re doing just fine as it is. Actions to ”further minimize any possibility of errors in future reports” should not be their top priority. Further extending the review process will only further delay the publication of each report (making them even more out of date) and further enhance their lowest-common-denominator position. When you have an error rate on the order of 0.67 errors/1000 pages, should you spend your energy getting that all the way down to zero (a virtually impossible task) or on the real issues that need to be addressed?

I think the IPCC should adopt a continually-updating online version of their report. This would solve their chronic problem of being out of date, as well as help the organization adapt to the increasing role of the Internet in our world. Any future errors the deniers liked to yell about would be fixed immediately. Governments would be forming policies based on the best available evidence from today, not a decade ago. Everything would still be in one place, and version control would allow transparency to remain high.

The IPCC should also make it more clear when their estimates are too conservative. When a single sentence that didn’t even make it into the summary is shown to overestimate the problem, the climate science community ties itself up in knots trying to correct its tattered image. But prominent conclusions that underestimate the problem go unacknowledged for decades. If it were the other way around, can you imagine the field day deniers would have?

Luckily, the changes made to IPCC policy are not all aimed at appeasing the bullies. A long-overdue communications plan is in development: a rapid response team and Senior Communications Manager will develop formal strategies for public education and outreach. Hopefully, this will counteract the false claims and defamation the IPCC has been subject to since its creation.

Another new plan is to create an Executive Committee, composed of the Chair, Vice Chairs, Working Group Co-Chairs, and advisory members. This will “strengthen coordination and management of the IPCC” and allow for actions to be taken between reports, such as communication and responding to possible errors. A more structured administration will probably be helpful, given that the only people in the organization currently getting paid for their work are the office staff (even the Chair doesn’t make a cent). Coordinating overworked scientists who volunteer for a scientific undertaking that demands 100% accuracy can’t be an easy task.

Will the IPCC continue to be the best available source of credible information on climate change? Will its structure of endless review remain feasible in a world dominated by instant news? Should we continue to grant our governments control over the contents of scientific reports concerning an issue that they desperately want to avoid? Should we continue to play to the wants and needs of bullies? Or should we let scientists speak for themselves?

It has been a bad season for tornadoes in the United States. In fact, this April shattered the previous record for the most tornadoes ever. Even though the count isn’t finalized yet, nobody doubts that it will come out on top:

In a warming world, many questions are common, and quite reasonable. Is this a sign of climate change? Will we experience more, or stronger, tornadoes as the planet warms further?

In fact, these are very difficult questions to answer. First of all, attributing a specific weather event, or even a series of weather events, to a change in the climate is extremely difficult. Scientists can do statistical analysis to estimate the probability of the event with and without the extra energy available in a warming world, but this kind of study takes years. Even so, nobody can say for certain whether an event wasn’t just a fluke. The recent tornadoes very well might have been caused by climate change, but they also might have happened anyway.

Will tornadoes become more common in the future, as global warming progresses? Tornado formation is complicated, and forecasting them requires an awful lot of calculations. Many processes in the climate system are this way, so scientists simulate them using computer models, which can do detailed calculations at an increasingly impressive speed.

However, individual tornadoes are relatively small compared to other kinds of storms, such as hurricanes or regular rainstorms. They are, in fact, smaller than a single square in the highest-resolution climate models around today. Therefore, it’s just not possible to directly project them using mathematical models.

However, we can project the conditions necessary for tornadoes to form. They don’t always lead to a tornado, but they make one more likely. Two main factors exist: high wind shear and high convective available potential energy (CAPE). Climate change is making the atmosphere warmer, and increasing specific humidity (but not relative humidity): both of these contribute to CAPE, so that factor will increase the likelihood of conditions favourable to tornadoes. However, climate change warms the poles faster than the equator, which will decrease the temperature difference between them, subsequently lowering wind shear. That will make tornadoes less likely (Diffenbaugh et al, 2008). Which factor will win out? Is there another factor involved that climate change could impact? Will we get more tornadoes in some areas and less in others? Will we get weaker tornadoes or stronger tornadoes? It’s very difficult to tell.

In 2007, NASA scientists used a climate model to project changes in severe storms, including tornadoes. (Remember, even though an individual tornado can’t be represented on a model, the conditions likely to cause a tornado can.) They predicted that the future will bring fewer storms overall, but that the ones that do form will be stronger. A plausible solution to the question, although not a very comforting one.

With uncertain knowledge, how should we approach this issue? Should we focus on the comforting possibility that the devastation in the United States might have nothing to do with our species’ actions? Or should we acknowledge that we might bear responsibility? Dr. Kevin Trenberth, a top climate scientist at the National Center for Atmospheric Research (NCAR), thinks that ignoring this possibility until it’s proven is a bad idea. “It’s irresponsible not to mention climate change,” he writes.

A landmark report (summary available here) was published this week by the National Research Council in the United States, which is part of the National Academy of Sciences. The report, “America’s Climate Choices”, was requested by Congress several years ago. It focused on the observed impacts of climate change in the United States, as well as the policy choices most likely to be effective.

The report was created not just by scientists, but also by business executives and politicians. The diverse author committee is made apparent in the report’s message. Climate scientists tend to follow the IPCC mantra of “policy-relevant but policy-neutral” – they might discuss the potential ramifications of different policy choices, but they don’t recommend one over the other.

In contrast, this report includes phrases such as, ”Current efforts of local, state, and private sector actors are important, but not likely to yield progress comparable to what could be achieved with the addition of strong federal policies that establish coherent national goals and incentives, and that promote strong U.S. engagement in international-level response efforts.” This is toeing the line of policy-prescriptive. It doesn’t hesitate to say that some policy options will be better than others for reducing global warming, and that the policy option of doing nothing would be foolish.

More specifically, the authors recommend a price on carbon, and describe a system similar to a carbon tax for the most effective option. They also name elements of what they see to be the best course of action for the United States:

• “significantly reduce greenhouse gas emissions”
• “begin mobilizing now for adaptation”
• “invest in science, technology, and information systems”
• “participate in international climate change response efforts”
• “coordinate national response efforts”

These recommendations conflict with many postulates of the conservative American ideology. “Historically there’s only one thing Congress dislikes more than science and that’s international treaties,” writes Kevin Grandia, and this report recommends both. It’s no surprise, then, that Tea Party politicians are dismissing the report out of hand, as the New York Times reports. Apparently, Joe Barton thinks that doing nothing about climate change is a viable policy option. Fifty years from now, when civilizations and ecosystems worldwide are struggling to survive the impacts of climate change, what will history books say about Joe Barton?

The New York Times article illustrates much of what is wrong with mainstream climate journalism. It balances a massive report from the National Academy of Sciences with statements from an extremist politician. Additionally, it does a hilarious job of framing decades-old scientific findings as new and controversial, as if this report was the first to discuss them. “Not only is global warming real, but the effects are already becoming serious,” writes the New York Times. “Not only is the science behind the climate-change forecast solid, the report found, but the risks to future generations from further inaction are profound.”

If this is news to the New York Times, they need to catch up on their science. Right now, they’re stuck in the 1980s.

There are several familiar names among the nominees, including meteorology professor and frequent ClimateSight commenter Scott Mandia, the ever-brilliant Naomi Oreskes, and the growing organization of Skeptical Science.

Voting is quick and easy, and only requires an email address. Please be sure to cast your vote before April 15th and support the community!

In the current economy, it’s not surprising that many countries are reducing funds for scientific research. It’s necessary to cut spending across the board these days. However, North American governments are singling out climate science as a victim – and not just reducing its funding, but, in many cases, eliminating it altogether.

Climate change research is largely supported by government money, as there aren’t many industries that recognize a vested interest in the science. Pharmaceutical companies often fund biomedical researchers, and mining companies fund geologists, but there’s no real analogue for climate scientists. Additionally, many global warming studies are particularly expensive. For example, transporting researchers and equipment to the North Pole via helicopter, and building climate models on supercomputers that stretch the limits of our data storage capacities, cost quite a bit more than injecting rats with chemicals in a lab.

In Canada, where I live, the federal government recognized these unique characteristics of climate science, and, in 2000, set up a special foundation to fund research in the field: the Canadian Foundation for Climate and Atmospheric Sciences (CFCAS). Over the past decade, it has spent $118 million supporting most of Canada’s university-based climate research, and it was assumed that it would be continually renewed as the country established itself as a leader in the field.

However, since the Conservative Party formed a minority government almost five years ago, it has only extended the foundation’s lifespan by a year, and refuses to consider long-term funding commitments. The CFCAS only has a few months left before it will run out of money and close its doors. Many of Canada’s premier climate research projects and laboratories will have to shut down as a result, as they have always relied on CFCAS, and general federal funds such as the National Science and Engineering Research Council (NSERC) simply won’t be able to fill the gap. Some researchers are leaving the country to pursue more fertile academic ground, and as an aspiring climate scientist, I am wondering whether I will have to eventually do so as well.

If it seems cruel to abandon funding for researching the greatest threat to our future, rather than simply reducing its budget until the economy recovers, take a stroll south to what my sociology professor likes to refer to as “that wild society”. The U.S. House of Representatives is becoming dominated by politicians who hate the idea of government, and wish to tear most of it down in anger. Add to that mindset a staunch denial of climate science, and you can see where this is going.

The House of Representatives just passed a bill that not only prevents the Environmental Protection Agency from regulating greenhouse gases that cause climate change, but also repeals a great deal of clean air and water protection. Other cornerstones of the bill include repealing the new American health care system and cutting off funding of Planned Parenthood.

Since not a single Democrat Member of Congress voted for this bill, it is unlikely to pass the Senate, where Democrats hold a majority. However, Republicans have threatened to take away all federal funding, effectively shutting down the entire U.S. government, if the bill is not passed into law.

An amendment to this bill, which also passed the House of Representatives, completely cuts off federal funding to the Intergovernmental Panel on Climate Change (IPCC). The IPCC, a scientific organization of the United Nations, doesn’t do any original research, but writes extensive summary reports of the academic literature on climate change. It’s hard to overestimate how important these reports, published every few years, are to governments, scientists, and citizens alike. Instead of having to dig through thousands of scientific journals and articles, with no idea where to start, people can simply read these reports to find out what science knows about climate change. They are painstakingly reviewed, are offered in several levels of technicality, and include carefully organized references to the multitude of studies whose conclusions contributed to the text. For a field of research that is quickly expanding, these reports are absolutely vital, and it’s hard to imagine how they could carry on without support from the American government.

Blaine Luetkemeyer, the Republican Member of Congress that proposed the amendment, justified cutting off the IPCC by asserting the oft-debunked, but disturbingly popular, meme that climate science is some kind of worldwide conspiracy. If the IPCC really is “corrupt” and “nefarious”, as Luetkemeyer claims, then why can’t they afford to pay any of the scientists that write the reports – not even the IPCC president? Why do they allow anyone to help review the draft reports? Why do they permit their Summary for Policymakers to be watered down by policymakers? And, most importantly, why is climate change progressing faster than the IPCC expected?

We shouldn’t have to spend time addressing paranoid conspiracy theories like Luetkemeyer’s . Sadly, the government of the most powerful country on Earth is being taken over by people who buy into these conspiracy theories, and who want to punish climate scientists as much as possible for crimes they haven’t committed. Countries like Canada, even if they refrain from public accusations, are following suit in their actions.

“It’s quite clear by their actions [with CFCAS] and its lack of funding that [the Canadian government is] basically saying ‘We don’t want your science any more’,” Andrew Weaver, Canada’s top climatologist, told the Globe and Mail.

“[Cutting off the IPCC] is like putting our heads in the sand, denying the science, and then stopping the scientists from working – because they might come to a different conclusion from the Republican Party’s ideology,” Democrat Member of Congress Henry Waxman argued.

Is this really a wise move?

Climate change is a worrying phenomenon, but watching it unfold can be fascinating. The beginning of a new year brings completed analysis of what last year’s conditions were like. Perhaps the most eagerly awaited annual statistic is global temperature.

This year was no different – partway through 2010, scientists could tell that it had a good chance of being the warmest year on record. It turned out to be more or less tied for first, as top temperature analysis centres recently announced:

• “Global surface temperatures in 2010 tied 2005 as the warmest on record,” announced NASA’s climate change team at GISS.
• “2010…tied with 2005 as the warmest such period on record,” the National Oceanic and Atmospheric Administration (NOAA) similarly concluded.
• “Provisional global temperature records for 2010…show the year to be the second warmest on record [after 1998],” the UK Met Office found.
• “The year 2010 ranked as the warmest year on record, together with 2005 and 1998,” was the World Meteorological Organization’s response.

Why the small discrepancy in the order of  1998, 2005, and 2010? The answer is mainly due to the Arctic. Weather stations in the Arctic region are few and far between, as it’s difficult to have a permanent station on ice floes that move around, and are melting away. Scientists, then, have two choices in their analyses: extrapolate Arctic temperature anomalies from the stations they do have, or just leave the missing areas out, assuming that they’re warming at the global average rate. The first choice might lead to results that are off in either direction…but the second choice almost certainly underestimates warming, as it’s clear that climate change is affecting the Arctic much more and much faster than the global average. Currently, NASA is the only centre to do extrapolation in Arctic data. A more detailed explanation is available here.

But how useful is an annual measurement of global temperature? Not very, as it turns out. Short-term climate variability, most prominently El Nino and La Nina, impact annual temperatures significantly. Furthermore, since this oscillation occurs in the winter, the thermal influence of El Nino or La Nina can fall entirely into one calendar year, or be split between two. The result is a graph that’s rather spiky:

A far more useful analysis involves plotting a 12-month running mean. Instead of measuring only from January to December, measurements are also compiled from February to January, March to February, and so on. This results in twelve times more data points, and prevents El Nino and La Nina events from being exaggerated:

This graph is better, but still not that useful. The natural spikiness of the El Nino cycle can, in the short term, get in the way of understanding the underlying trend. Since the El Nino cycle takes between 3 and 7 years to complete, a 60-month (5-year) running mean allows the resulting ups and downs to cancel each other out. Another cycle that impacts short-term temperature is the sunspot cycle, which operates on an 11-year cycle. A 132-month running mean smooths out that influence too. Both 60- and 132- month running means are shown below:

A statistic every month that shows the average global temperature over the last 5 or 11 years may not be as exciting as an annual measurement regarding the previous year. But that’s the reality of climate change. It doesn’t make every month or even every year warmer than the last, and a short-term trend line means virtually nothing. In the climate system, trends are always obscured by noise, and the nature of human psychology means we pay far more attention to noise. Nonetheless, the long-term warming trend since around 1975 is irrefutable when one is presented with the data. A gradual, persistent change might not make the greatest headline, but that doesn’t mean it’s worth ignoring.

The GCM output this paper analysed suggested that there is hope. They found the relationship between temperature and sea ice cover to be more linear, and the ice-albedo feedback in the Arctic to be weaker, than we previously thought. Tipping points where sea ice is beyond hope might not be such a problem. Therefore, we may still have a chance to limit damage to the ecosystem that experiences consequences of climate change earliest and strongest, and the polar bears might still make it. Nature News has a great summary for those who want more detail on the literature.

When the story showed up in my CBC News feed, however, I was bewildered at the angle they took:

Polar bears could be saved from extinction if greenhouse gas emissions are significantly reduced in the next decade or two, a study released Wednesday suggests.

As if that’s the most compelling reason to pursue mitigation…

Don’t get me wrong: it would be a shame to see the polar bears go. But it would be much worse to see agriculture in the subtropics go, or to see low-lying nations go. I believe that the public is wise enough to understand that sentimental notions about an oft-romanticized species are minuscule in their importance when compared to matters of human security.

Additionally, since polar bears reside at the top of the food chain, the ecological consequences of their loss – while certainly not trivial – would probably be less intense than if it were another species. Imagine the hypothetical scenario of termites going extinct – it would be much worse. Termites aren’t quite so cute and cuddly, though.

I continue to be amazed by choices that the mainstream media makes as to which studies to report on and which studies to ignore. Their picture of ordinary people’s priorities is baffling and somewhat insulting. I get it - I have a strong affinity for wildlife – but the species I care about the most is still Homo sapiens, despite its blatant shortcomings.

Take a look – many of the statements are what you would expect from trolling YouTube commenters, not politicians aspiring to run the most powerful country in the world. Through a combination of framing science as personal opinion, promoting artificial balance, and re-iterating the same misconceptions that people like you and I have been fighting to correct for years now, the Republican party has adopted a position that, frankly, terrifies me.

“There are dramatic environmental changes happening the Arctic region – whether one believes they are man-made or natural.” – John McCain, Arizona

“While I think the earth is warming, I don’t think that man-made causes are the primary factor.” – Ken Buck, Colorado

“The climate is always changing. The climate is never static. The question is whether it’s caused by man-made activity and whether it justifies economically destructive government regulation.” -Marco Rubio, Florida

“[Scientists] are making up their facts to fit their conclusions. They’ve already caught them doing this.” – Rand Paul, Kentucky

“There isn’t any real science to say we are altering the climate path of the Earth.” -Roy Blunt, Missouri

“I don’t buy into the whole man-caused global warming, man-caused climate change mantra of the left. I believe that there’s not sound science to back that up.” -Sharron Angle, Nevada

“There is much debate in the scientific community as to the precise sources of global warming.” -Pat Toomey, Pennsylvania

“It’s going to keep snowing in DC until Al Gore cries ‘uncle’.” -Jim DeMint, South Carolina

“If you have one volcano in the world, that one volcano puts out more carbon dioxide than everything man puts out.” -John Raese, West Virginia

“I absolutely do not believe that the science of man-caused climate change is proven. Not by any stretch of the imagination. I think it’s far more likely that it’s just sunspot activity, or something just in the geologic eons of time where we have changes in the climate.” -Ron Johnson, Wisconsin

Who are these people to make statements about what the scientific community knows and does not know about climate change, when organizations like the NAS are quite capable of doing that themselves, and tell a very different story to these prospective Senators when they do?

Who are they to make informal analyses on the attribution of recent temperature change – assessing the likelihood of different causes via gut instinct, rather than looking at fingerprints like stratospheric temperature and tropopause height?

Who are they to spread around blatant mistruths like “a single volcano puts out more CO2 than people do”? Who are they to make damaging accusations about scientific fraud and false data, especially when these accusations have already been investigated multiple times, coming up completely clear?

I had hoped that politicians would be slightly more informed than the general public on scientific matters that have implications for policy. However, I must now change my mind, and hope instead that the American public realizes how off the mark this position is. If they don’t, there could be consequences up to millenia from now.