Tornadoes and Climate Change

Cross-posted from NextGen Journal

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.

Beautiful Things

This is what the last few days have taught me: even if the code for climate models can seem dense and confusing, the output is absolutely amazing.

Late yesterday I discovered a page of plots and animations from the Canadian Centre for Climate Modelling and Analysis. The most recent coupled global model represented on that page is CGCM3, so I looked at those animations. I noticed something very interesting: the North Atlantic, independent of the emissions scenario, was projected to cool slightly, while the world around it warmed up. Here is an example, from the A1B scenario. Don’t worry if the animation is already at the end, it will loop:

It turns out that this slight cooling is due to the North Atlantic circulation slowing down, as is very likely to happen from large additions of freshwater that change the salinity and density of the ocean (IPCC AR4 WG1, FAQ 10.2). This freshwater could come from either increased precipitation due to climate change, or meltwater from the Arctic ending up in the North Atlantic. Of course, we hear about this all the time – the unlikely prospect of the Gulf Stream completely shutting down and Europe going into an ice age, as displayed in The Day After Tomorrow – but, until now, I hadn’t realized that even a slight slowing of the circulation could cool the North Atlantic, while Europe remained unaffected.

Then, in chapter 8 of the IPCC, I read something that surprised me: climate models generate their own El Ninos and La Ninas. Scientists don’t understand quite what triggers the circulation patterns leading to these phenomena, so how can they be in the models? It turns out that the modellers don’t have to parameterize the ENSO cycles at all: they have done such a good job of reproducing global circulation from first principles that ENSO arises by itself, even though we don’t know why. How cool is that? (Thanks to Jim Prall and Things Break for their help with this puzzle.)

Jim Prall also pointed me to an HD animation of output from the UK-Japan Climate Collaboration. I can’t seem to embed the QuickTime movie (WordPress strips out some of the necessary HTML tags) so you will have to click on the link to watch it. It’s pretty long – almost 17 minutes – as it represents an entire year of the world’s climate system, in one-hour time steps. It shows 1978-79, starting from observational data, but from there it simulates its own circulation.

I am struck by the beauty of this output – the swirling cyclonic precipitation, the steady prevailing westerlies and trade winds, the subtropical high pressure belt clear from the relative absence of cloud cover in these regions. You can see storms sprinkling across the Amazon Basin, monsoons pounding South Asia, and sea ice at both poles advancing and retreating with the seasons. Scientists didn’t explicitly tell their models to do any of this. It all appeared from first principles.

Take 17 minutes out of your day to watch it – it’s an amazing stress reliever, sort of like meditation. Or maybe that’s just me…

One more quick observation: most of you are probably familiar with the naming conventions of IPCC reports. The First Assessment Report was FAR, the second was SAR, and so on, until the acronyms started to repeat themselves, so the Fourth Assessment Report was AR4. They’ll have to follow this alternate convention until the Eighth Annual Report, which will be EAR. Maybe they’ll stick with AR8, but that would be substantially less entertaining.

Learning Experiences

I apologize for my brief hiatus – it’s been almost two weeks since I’ve posted. I have been very busy recently, but for a very exciting reason: I got a job as a summer student of Dr. Steve Easterbrook! You can read more about Steve and his research on his faculty page and blog.

This job required me to move cities for the summer, so my mind has been consumed with thoughts such as “Where am I and how do I get home from this grocery store?” rather than “What am I going to write a post about this week?” However, I have had a few days on the job now, and as Steve encourages all of his students to blog about their research, I will use this outlet to periodically organize my thoughts.

I will be doing some sort of research project about climate modelling this summer – we’re not yet sure exactly what, so I am starting by taking a look at the code for some GCMs. The NCAR Community Earth System Model is one of the easiest to access, as it is largely an open source project. I’ve only read through a small piece of their atmosphere component, but I’ve already seen more physics calculations in one place than ever before.

I quickly learned that trying to understand every line of the code is a silly goal, as much as I may want to. Instead, I’m trying to get a broader picture of what the programs do. It’s really neat to have my knowledge about different subjects converge so completely. Multi-dimensional arrays, which I have previously only used to program games of Sudoku and tic-tac-toe, are now being used to represent the entire globe. Electric potential, a property I last studied in the circuitry unit of high school physics, somehow impacts atmospheric chemistry. The polar regions, which I was previously fascinated with mainly for their wildlife, also present interesting mathematical boundary cases for a climate model.

It’s also interesting to see how the collaborative nature of CESM, written by many different authors and designed for many different purposes, impacts its code. Some of the modules have nearly a thousand lines of code, and some have only a few dozen – it all depends on the programming style of the various authors. The commenting ranges from extensive to nonexistent. Every now and then one of the files will be written in an older version of Fortran, where EVERYTHING IS IN UPPER CASE.

I am bewildered by most of the variable names. They seem to be collections of abbreviations I’m not familiar with. Some examples are “mxsedfac”, “lndmaxjovrdmdni”, “fxdd”, and “vsc_knm_atm”.

When we get a Linux machine set up (I have heard too many horror stories to attempt a dual-boot with Windows) I am hoping to get a basic CESM simulation running, as well as EdGCM (this could theoretically run on my laptop, but I prefer to bring that home with me each evening, and the simulation will probably take over a day).

I am also doing some background reading on the topic of climate modelling, including this book, which led me to the story of PHONIAC. The first weather prediction done on a computer (the ENIAC machine) was recreated as a smartphone application, and ran approximately 3 million times faster. Unfortunately, I can’t find anyone with a smartphone that supports Java (argh, Apple!) so I haven’t been able to try it out.

I hope everyone is having a good summer so far. A more traditional article about tornadoes will be coming at the end of the week.

Thoughts

My presentation went very well. The church group was full of kind, educated, and passionate people. It was nice to have an audience that wasn’t full of high school students who thought science was boring!

After the presentation, a woman in the group shared something with me that she found at a conference in Australia just before the Copenhagen summit. I liked it so much that I thought I’d share it here, with her permission.

If the earth
were only a few feet in
diameter, floating a few feet above
a field somewhere, people would come
from everywhere to marvel at it. People would
walk around it marvelling at its big pools of water,
its little pools and the water flowing between the pools.
People would marvel at the bumps on it, and the holes in it,
and they would marvel at the very thin layer of gas surrounding
it and the water suspended in the gas. The people would
marvel at all the creatures walking around the surface of the ball
and at the creatures in the water. The people would declare it
as sacred because it was the only one and they would protect
it so that it would not be hurt. The ball would be the
greatest wonder known and people around would come to
pray to it, to be healed, to gain knowledge, to know
beauty and to wonder how it could be. People
would love it and defend it with their lives
because they would somehow know that
their lives, their own roundness, could
be nothing without it. If the
Earth were only a few
feet in diameter.

-Joe Miller

What Can One Person Do?

Next week, I will be giving a speech on climate change to the green committee of a local United Church. They are particularly interested in science and solutions, so I wrote the following script, drawing heavily from my previous presentations. I would really appreciate feedback and suggestions for this presentation.

Citations will be on the slides (which I haven’t made yet), so they’re not in the text of this script. Let me know if there’s a particular reference you’re wondering about, but they’re probably common knowledge within this community by now.

Enjoy!

Climate change is depressing. I know that really well, because I’ve been studying it for over two years. I’m quite practiced at keeping the scary stuff contained in the analytical part of my brain, and not thinking of the implications – because the implications make you feel powerless. I’m sure that all of us here wish we could stop global warming on our own. So we work hard to reduce our carbon footprints, and then we feel guilty every time we take the car out or buy something that was made in China or turn up the heat a degree.

The truth is, though, the infrastructure of our society doesn’t support a low-carbon lifestyle. Look at the quality of public transit in Winnipeg, or the price of local food. We can work all we want at changing our practices, but it’s an uphill battle. If we change the infrastructure, though – if we put a price on carbon so that sustainable practices are cheaper and easier than using fossil fuels – people everywhere will subsequently change their practices.

Currently, governments – particularly in North America – aren’t too interested in sustainable infrastructure, because they don’t think people care. Politicians only say what they think people want to hear. So, should we go dress up as polar bears and protest in front of Parliament to show them we care? That might work, but they will probably just see us as crazy environmentalists, a fringe group. We need a critical mass of people that care about climate change, understand the problem, and want to fix it. An effective solution requires top-down organization, but that won’t happen until there’s a bottom-up, grassroots movement of people who care.

I believe that the most effective action one person can take in the fight against global warming is to talk to others and educate others. I believe most people are good, and sane, and reasonable. They do the best they can, given their level of awareness. If we increase that awareness, we’ll gain political will for a solution. And so, in an effort to practice what I preach, I’m going to talk to you about the issue.

The science that led us to the modern concern about climate change began all the way back in 1824, when a man named Joseph Fourier discovered the greenhouse effect. Gases such as carbon dioxide make up less than one percent of the Earth’s atmosphere, but they trap enough heat to keep the Earth over 30 degrees Celsius warmer than it would be otherwise.

Without greenhouse gases, there could be no life on Earth, so they’re a very good thing – until their concentration changes. If you double the amount of CO2 in the air, the planet will warm, on average, somewhere around 3 degrees. The first person to realize that humans could cause this kind of a change, through the burning of fossil fuels releasing CO2, was Svante Arrhenius, in 1897. So this is not a new theory by any means.

For a long time, scientists assumed that any CO2 we emitted would just get absorbed by the oceans. In 1957, Roger Revelle showed that wasn’t true. The very next year, Charles Keeling decided to test this out, and started measuring the carbon dioxide content of the atmosphere. Now, Arrhenius had assumed that it would take thousands of years to double CO2 from the preindustrial value of 280 ppm (which we know from ice cores), but the way we’re going, we’ll get there in just a few decades. We’ve already reached 390 ppm. That might not seem like a lot, but 390 ppm of arsenic in your coffee would kill you. Small changes can have big effects.

Around the 1970s, scientists realized that people were exerting another influence on the climate. Many forms of air pollution, known as aerosols, have a cooling effect on the planet. In the 70s, the warming from greenhouse gases and the cooling from aerosols were cancelling each other out, and scientists were split as to which way it would go. There was one paper, by Stephen Schneider, which even said it could be possible to cause an ice age, if we put out enough aerosols and greenhouse gases stayed constant. However, as climate models improved, and governments started to regulate air pollution, a scientific consensus emerged that greenhouse gases would win out. Global warming was coming – it was just a question of when.

In 1988, James Hansen, who is arguably the top climate scientist in the world today, claimed it had arrived. In a famous testimony to the U.S. Congress, he said that “the greenhouse effect has been detected, and it is changing our climate now.” Many scientists weren’t so sure, and thought it was too early to make such a bold statement, but Hansen turned out to be right. Since about 1975, the world has been warming, more quickly than it has for at least the last 55 million years.

Over the past decade, scientists have even been able to rule out the possibility that the warming is caused by something else, like a natural cycle. Different causes of climate change have slightly different effects – like the pattern of warming in different layers of the atmosphere, the amount of warming in summer compared to winter, or at night compared to in the day, and so on. Ben Santer pioneered attribution studies: examining these effects in order to pinpoint a specific cause. And so far, nobody has been able to explain how the recent warming could not be caused by us.

Today, there is a remarkable amount of scientific agreement surrounding this issue. Between 97 and 98% of climate scientists, virtually 100% of peer-reviewed studies, and every scientific organization in the world agree that humans are causing the Earth to warm. The evidence for climate change is not a house of cards, where you take one piece out and the whole theory falls apart. It’s more like a mountain. Scrape a handful of pebbles off the top, but the mountain is still there.

However, if you take a step outside of the academic community, this convergence of evidence is more or less invisible. The majority of newspaper articles, from respected outlets like the New York Times or the Wall Street Journal, spend at least as much time arguing against this consensus as they do arguing for it. They present ideas such as “maybe it’s a natural cycle” or “CO2 has no effect on climate” that scientists disproved years ago. The media is stuck in the past. Some of them are only stuck in the 1980s, but others are stuck all the way back in 1800. Why is it like this?

Part of it comes from good, but misguided, intentions. When it comes to climate change, most journalists follow the rule of balance: presenting “two equal sides”, staying neutral, letting the reader form their own opinion. This works well when the so-called controversy is one of political or social nature, like tax levels or capital punishment. In these cases, there is no right answer, and people are usually split into two camps. But when the question at hand is one of science, there is a right answer – even if we haven’t found it yet – so some explanations are better than others, and some can be totally wrong. Would you let somebody form their own opinion on Newton’s Laws of Motion or the reality of photosynthesis? Sometimes scientists are split into two equal groups, but sometimes they’re split into three or four or even a dozen. How do you represent that as two equal sides? Sometimes, like we see with climate change, pretty much all the scientists are in agreement, and the two or three percent which aren’t don’t really publish, because they can’t back up their statements and nobody really takes them seriously. So framing these two groups as having equal weight in the scientific community is completely incorrect. It exaggerates the extreme minority, and suppresses everyone else. Being objective is not always the same as being neutral, and it’s particularly important to remember that when our future is at stake.

Another reason to frame climate science as controversial is that it makes for a much better story. Who really wants to read about scientists agreeing on everything? Journalists try to write stories that are exciting. Unfortunately, that goal can begin to overshadow accuracy.

Also, there are fewer journalists than there used to be, and there are almost no science journalists in the mainstream media – general reporters cover science issues instead. Also, a few decades ago, journalists used to get a week or two to write a story. Now they often have less than a day, because speed and availability of news has become more important than quality.

However, perhaps the most important – and disturbing – explanation for this inaccurate framing is that the media has been very compliant in spreading the message of climate change deniers. They call themselves skeptics, but I don’t think that’s accurate. A true skeptic will only accept a claim given sufficient evidence. That’s a good thing, and all scientists should be skeptics. But it’s easy to see that these people will never accept human-caused climate change, no matter what the evidence. At the same time, they blindly accept any shred of information that seems to support their cause, without applying any skepticism at all. That’s denial, so let’s not compliment them by calling them skeptics.

Climate change deniers will use whatever they can get – whether or not it’s legitimate, whether or not it’s honest – as proof that climate change is natural, or nonexistent, or a global conspiracy. They’ll tell you that volcanoes emit more CO2 than humans, but volcanoes actually emit about 1% of what we do. They’ll say that global warming has stopped because 2008 was cooler than 2007. If climatologists organize a public lecture in effort to communicate accurate scientific information, they’ll say that scientists are dogmatic and subscribe to censorship and will not allow any other opinions to be considered.

Some of these questionable sources are organizations, like a dozen or so lobby groups that have been paid a lot of money by oil companies to say that global warming is fake. Some of them are individuals, like US Senator James Inhofe, who was the environment chair under George W. Bush, and says that “global warming is the greatest hoax ever imposed upon the American people.” Some of them have financial motivations, and some of them have ideological motivations, but their motivations don’t really matter – all that matters is that they are saying things that are inaccurate, and misleading, and just plain wrong.

There has been a recent, and very disturbing, new tactic of deniers. Instead of attacking the science, they’ve begun to attack the integrity of individual scientists. In November 2009, they stole thirteen years of emails from a top climate research group in the UK, and spread stories all over the media that said scientists were caught fudging their data and censoring critics. Since then, they’ve been cleared of these charges by eight independent investigations, but you wouldn’t know it by reading the newspaper. For months, nearly every media outlet in the developed world spread what was, essentially, libel, and the only one that has formally apologized for its inaccurate coverage is the BBC.

In the meantime, there has been tremendous personal impact on the scientists involved. Many of them have received death threats, and Phil Jones, the director of the research group, was nearly driven to suicide. Another scientist, who wishes to remain anonymous, had a dead animal dumped on his doorstep and now travels with bodyguards. The Republican Party, which prides itself on fiscal responsibility, is pushing for more and more investigations, because they just can’t accept that the scientists are innocent…and James Inhofe, the “global warming is a hoax” guy, attempted to criminally prosecute seventeen researchers, most of whom had done nothing but occasionally correspond with the scientists who had their emails stolen. It’s McCarthyism all over again.

So this is where we are. Where are we going?

The Intergovernmental Panel on Climate Change, or IPCC, which collects and summarizes all the scientific literature about climate change, said in 2007 that under a business-as-usual scenario, where we keep going the way we’re going, the world will warm somewhere around 4 degrees Celsius by 2100. Unfortunately, this report was out of date almost as soon as it was published, and has widely been criticized for being too conservative. The British Meteorological Office published an updated figure in 2009 that estimated we will reach 4 degrees by the 2070s.

I will still be alive then (I hope!). I will likely have kids and even grandkids by then. I’ve spent a lot of time researching climate change, and the prospect of a 4 degree rise is terrifying to me. At 4 degrees, we will have lost control of the climate – even if we stop emitting greenhouse gases, positive feedbacks in the climate system will make sure the warming continues. We will have committed somewhere between 40 and 70 percent of the world’s species to extinction. Prehistoric records indicate that we can expect 40 to 80 metres of eventual sea level rise – it will take thousands of years to get there, but many coastal cities will be swamped within the first century. Countries – maybe even developed countries – will be at war over food and water. All this…within my lifetime.

And look at our current response. We seem to be spending more time attacking the scientists who discovered the problem than we are negotiating policy to fix it. We should have started reducing our greenhouse gas emissions twenty years ago, but if we start now, and work really hard, we do have a shot at stopping the warming at a point where we stay in control. Technically, we can do it. It’s going to take an unprecedented amount of political will and international communication

Everybody wants to know, “What can I do?” to fix the problem. Now, magazines everywhere are happy to tell you “10 easy ways to reduce your carbon footprint” – ride your bike, and compost, and buy organic spinach. That’s not really going to help. Say that enough people reduce their demand on fossil fuels: supply and demand dictates that the price will go down, and someone else will say, “Hey, gas is cheap!” and use more of it. Grassroots sentiment isn’t going to be enough. We need a price on carbon, whether it’s a carbon tax or cap-and-trade…but governments won’t do that until a critical mass of people demand it.

So what can you do? You can work on achieving that critical mass. Engage the apathetic. Educate people. Talk to them about climate change – it’s scary stuff, but suck it up. We’re all going to need to face it. Help them to understand and care about the problem. Don’t worry about the crazy people who shout about socialist conspiracies, they’re not worth your time. They’re very loud, but there’s not really very many of them. And in the end, we all get one vote.

Change

If you know what these colours mean, you probably share my surprise:

For those of you who aren’t familiar with Canadian politics, past and present, here’s a quick brush-up. (If parliamentary democracy or constitutional monarchy is new to you, Rick Mercer gives a great explanation.)

Liberal Party (Red Seats)

  • Politics: More liberal than the American Democrats, but not by a huge amount.
  • How they usually do: They’ve won elections so many times that they’re deemed “Canada’s natural government”. Whether it’s a majority or a minority, a Liberal government is the rule, rather than the exception.
  • What happened on Monday: 34 Liberal MPs were elected – only 11% of the available seats. The leader of the party, Michael Ignatieff, wasn’t even elected in his riding – a rare (but not unprecedented) occurrence.

Conservative Party (Dark Blue Seats)

  • Politics: Somewhere between American Republicans and Democrats. Canada’s most right-wing party that’s mainstream enough to win seats.
  • How they usually do: When it’s not a Liberal government, it’s a Conservative one. The last time they had a majority, it was under Brian Mulroney – an event that eventually led to the party’s collapse and division. The two halves of the party rejoined for the 2004 election, under Stephen Harper, the leader of the more right-wing of the two. Since 2006, he has held seemingly never-ending minorities. Again, Rick Mercer hits the nail on the head.
  • What happened on Monday: They got their first majority – 54% of the seats, but with only 40% of the popular vote.

Bloc Quebecois (Light Blue Seats)

  • Politics: Diverse, as the party’s sole platform is the intent to make Quebec a sovereign nation. These days, it’s pretty liberal.
  • How they usually do: Fifty-some seats in Quebec.
  • What happened on Monday: Only four Bloc were elected – most seats were lost to the NDP. The leader, Gilles Duceppe, lost the election in his riding. Now they don’t even have enough seats for party status.

New Democrat Party (Orange Seats)

  • Politics: The most liberal of the mainstream parties, they subscribe to social democracy. If Tea Partiers think Obama’s a socialist, I wonder what they’d say if the NDP swept the US Congress.
  • How they usually do: Twenty seats or so, scattered throughout the country, but rarely any from Quebec.
  • What happened on Monday: The NDP unexpectedly swept Quebec, and won 102 seats – for the first time, they’re the Official Opposition. Many of their MPs are brand new and never expected to get elected. Some are still university students. One spent her campaign in Las Vegas, but ended up winning the riding. Their growing popularity wasn’t limited to Quebec, but in many ridings – most notably some in Ontario – they split the vote with the Liberals, giving a lot of seats to the Conservatives.

Green Party (I’ll let you work out their colour of seats)

  • Politics: Not quite as left-wing as the NDP. They focus on environmental issues, climate change mitigation, and the legalization of marijuana.
  • How they usually do: Over the past few elections, they have held between 1 and 10% of the popular vote, but have never had an MP sit in Parliament. Once a Liberal MP switched to the Green Party, but Parliament was dissolved for an election before he got to sit in it as a member of the Greens.
  • What happened on Monday: Elizabeth May, the party leader, won the election in her riding, defeating a Conservative cabinet minister. She is the first elected Green and will be the first to sit in the House of Commons.

If that isn’t enough to convince you of what a massive change this election was, look at the diagrams on this page. Start at the bottom for the most recent Parliaments.

It is arguable that, although the Conservatives only have 40% of the popular vote, Stephen Harper has 100% of the power in the federal government. They hold a majority not only in the House of Commons, but also in the Senate – their five years of minorities have ensured that only Conservatives get appointed to the upper house. It is common for party leaders to demand that their caucus vote the party line on important issues, so Harper can pass pretty much any bill he wants. Also, unless his own party turns against him, he doesn’t have to call an election for another five years. Despite a more left-wing opposition that will be stronger on issues such as climate change (Elizabeth May, in particular, is a fabulous debater), they can’t actually sway results away from what Harper wants. Additionally, the new NDP MPs will have to prove their worth quickly if they want to be taken seriously.

But this is nothing new. It’s nothing specific to Harper. This concentration of power happened before with all the Liberal majority governments, as well as the Conservative exceptions such as Mulroney. This is the way majority governments in Canada work. They will pass a great deal of legislation in their favour, much of which will be undone when the opposing party eventually takes over. I am just worried because, given the Conservatives’ stance on climate change mitigation, we will likely move backwards on an issue where we don’t have time to waste. These decisions, or lack thereof, cannot be undone or reversed.

Thoughts?

Data from Elections Canada

More coverage from CBC News

An Unmeasured Forcing

“It is remarkable and untenable that the second largest forcing
that drives global climate change remains unmeasured,” writes Dr. James Hansen, the head of NASA’s climate change research team, and arguably the world’s top climatologist.

The word “forcing” refers to a factor, such as changes in the Sun’s output or in atmospheric composition, that exerts a warming or cooling influence on the Earth’s climate. The climate doesn’t magically change for no reason – it is always driven by something. Scientists measure these forcings in Watts per square metre – imagine a Christmas tree lightbulb over every square metre of the Earth’s surface, and you have 1 W/m2 of positive forcing.

Currently, the largest forcing on the Earth’s climate is that of increasing greenhouse gases from burning fossil fuels. These exert a positive, or warming, forcing, hence the term “global warming”. However, a portion of this positive forcing is being cancelled out by the second-largest forcing, which is also anthropogenic. Many forms of air pollution, collectively known as aerosols, exert a negative (cooling) forcing on the Earth’s climate. They do this in two ways: the direct albedo effect (scattering solar radiation so it never reaches the planet), and the indirect albedo effect (providing surfaces for clouds to form and scatter radiation by themselves). A large positive forcing and a medium negative forcing sums out to a moderate increase in global temperatures.

Unfortunately, a catch-22 exists with aerosols. As many aerosols are directly harmful to human health, the world is beginning to regulate them through legislation such as the American Clean Air Act. As this pollution decreases, its detrimental health effects will lessen, but so will its ability to partially cancel out global warming.

The problem is that we don’t know how much warming the aerosols are cancelling – that is, we don’t know the magnitude of the forcing. So, if all air pollution ceased tomorrow, the world could experience a small jump in net forcing, or a large jump. Global warming would suddenly become much worse, but we don’t know just how much.

The forcing from greenhouse gases is known with a high degree of accuracy – it’s just under 3 W/m2. However, all we know about aerosol forcing is that it’s somewhere around -1 or -2 W/m2 – an estimate is the best we can do. The reason for this dichotomy lies in the ease of measurement. Greenhouse gases last a long time (on the order of centuries) in the atmosphere, and mix through the air, moving towards a uniform concentration. An air sample from a remote area of the world, such as Antarctica or parts of Hawaii, will be uncontaminated by cars and factories nearby, and will contain an accurate value of the global atmospheric carbon dioxide concentration (the same can be done for other greenhouse gases, such as methane) . From these measurements, molecular physics can tell us how large the forcing is. Direct records of carbon dioxide concentrations have been kept since the late 1950s:

However, aerosols only stay in the troposphere for a few days, as precipitation washes them out of the air. For this reason, they don’t have time to disperse evenly, and measurements are not so simple. The only way to gain accurate measurements of their concentrations is with a satellite. NASA recently launched the Glory satellite for just this purpose. Unfortunately, it failed to reach orbit (an inherent risk for satellites), and given the current political climate in the United States, it seems overly optimistic to hope for funding for a new one any time soon. Luckily, if this project was carried out by the private sector, without the need for money-draining government review panels, James Hansen estimates that it could be achieved with a budget of around $100 million.

An accurate value for aerosol forcing can only be achieved with accurate measurements of aerosol concentration. Knowing this forcing would be immensely helpful for climate researchers, as it impacts not only the amount of warming we can expect, but also how long it will take to play out, until the planet reaches thermal equilibrium. Aimed with better knowledge of these details will allow policymakers to better plan for the future, regarding both mitigation of and adaptation to climate change. Finally measuring the impact of aerosols, instead of just estimating, could give our understanding of the climate system the biggest bang for its buck.

Where Activism Fails

Cross-posted from NextGen Journal

This weekend, 10 000 young people converged in Washington, D.C. and protested the American government’s inaction on climate change. Students stood in front of government buildings wearing green hard hats, holding signs saying “Make Polluters Pay, Not the EPA”. Students stormed the House of Representatives and sang a song about climate change, to the tune of the American national anthem. Fifteen minutes with President Obama, who agreed with their concerns but said “I can’t do this alone”, was PowerShift 2011’s biggest accomplishment.

This isn’t working.

The climate change mitigation lobby is currently a fringe group, at least in North America. It’s mostly made up of university students who mimic the campus protests of the 1960s, creating images that scream “socialism” to baby boomers who witnessed the original events. Governments, which are mostly made up of said baby boomers, largely ignore such fringe groups. Elected officials say what they think people want to hear, and most people don’t seem to care about climate change.

So what should we do instead? We don’t have a lot of money or connections to wealthy businesses. Youth don’t even vote in large enough numbers for governments to care what they want. What we do have, however, are facts on our side. We have the weight of the entire scientific community, agreeing that humans are causing a potentially catastrophic climate change which will only be stopped by major international action.

Instead of attempting to communicate with elected officials by marching around in front of their offices with our faces painted, I think we should focus our efforts on the public. If governments think people don’t care about climate change, we have to reverse that trend.

I believe that anyone who truly understands this issue will care about it and want to fix it. Who could honestly examine the overwhelming evidence for anthropogenic climate change and still have reasonable doubts about its existence? Who wouldn’t want to prevent future wars, famines, extinctions, and waves of environmental refugees? Of course, there are the crazies who will scream about “climate scientists in Al Gore’s pocket” and “the world needs more CO2” no matter what we tell them, but we shouldn’t bother engaging with these people. Instead, we should engage with those who are constantly exposed to the crazies, and who are at risk of dismissing climate change because they think people are still debating its existence.

We need public education to create a social movement, but not like the “Green Movement” in 2007 when magazines everywhere advertised “10 easy ways to reduce your carbon footprint”. We need people to understand the severity of climate change, and to see that planting a tree and buying organic lettuce will not solve the problem. We need people to understand that meaningful action, such as putting a price on carbon, is necessary to solve the problem.

Climate change education will spread most easily through the media, whether it is mass media or new media. People need to be aware of the level of scientific support surrounding this issue, and the reality that climate scientists are not ignorant or fraudulent. Researchers know that correlation does not equal causation, and they know that the climate has changed in the past. Many people still take these arguments seriously, though, because they are thrown around and not challenged. We need to challenge the media outlets that have spread dangerous, libelous misinformation regarding climate change for years. We need to challenge them on the level of lawsuits, not on the level of writing letters to the editor.

It is vital to engage with the apathetic and show them why they should care. Apathetic youth are particularly problematic. Why should the government care about the needs of the next generation when most of its members don’t even vote? We have to make the youth vote strong enough that political parties will compete for its support, just like they do with the ethnic vote and the women’s vote. As Canadian comedian and political analyst Rick Mercer said, “If you are between the ages of 18 and 25, and want to scare the hell out of the people who run this country – this time around, do the unexpected: vote.”

When faced with a depressing reality, many will turn away and ignore the problem. However, the only way to prevent the scary stuff from happening is to suck it up and face it. Just because we wasted 20 years of potential action and got ourselves into a bad situation doesn’t mean we should throw up our hands and give up. It’s never too late to act, because this bad situation can always get worse if we let it.

Climate Change Communicator of the Year Award

There’s just over a week left to vote in the Climate Change Communicator of the Year awards, run by the Centre for Climate Change Communication at George Mason University.

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!