Tag Archives: greenhouse gases

Modelling the Apocalypse

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Let’s all put on our science-fiction hats and imagine that humans get wiped off the face of the Earth tomorrow. Perhaps a mysterious superbug kills us all overnight, or maybe we organize a mass migration to live on the moon. In a matter of a day, we’re gone without a trace.

If your first response to this scenario is “What would happen to the climate now that fossil fuel burning has stopped?” then you may be afflicted with Climate Science. (I find myself reacting like this all the time now. I can’t watch The Lord of the Rings without imagining how one would model the climate of Middle Earth.)

A handful of researchers, particularly in Canada, recently became so interested in this question that they started modelling it. Their motive was more than just morbid fascination – in fact, the global temperature change that occurs in such a scenario is a very useful metric. It represents the amount of warming that we’ve already guaranteed, and a lower bound for the amount of warming we can expect.

Initial results were hopeful. Damon Matthews and Andrew Weaver ran the experiment on the UVic ESCM and published the results. In their simulations, global average temperature stabilized almost immediately after CO2 emissions dropped to zero, and stayed approximately constant for centuries. The climate didn’t recover from the changes we inflicted, but at least it didn’t get any worse. The “zero-emissions commitment” was more or less nothing. See the dark blue line in the graph below:

However, this experiment didn’t take anthropogenic impacts other than CO2 into account. In particular, the impacts of sulfate aerosols and additional (non-CO2) greenhouse gases currently cancel out, so it was assumed that they would keep cancelling and could therefore be ignored.

But is this a safe assumption? Sulfate aerosols have a very short atmospheric lifetime – as soon as it rains, they wash right out. Non-CO2 greenhouse gases last much longer (although, in most cases, not as long as CO2). Consequently, you would expect a transition period in which the cooling influence of aerosols had disappeared but the warming influence of additional greenhouse gases was still present. The two forcings would no longer cancel, and the net effect would be one of warming.

Damon Matthews recently repeated his experiment, this time with Kirsten Zickfeld, and took aerosols and additional greenhouse gases into account. The long-term picture was still the same – global temperature remaining at present-day levels for centuries – but the short-term response was different. For about the first decade after human influences disappeared, the temperature rose very quickly (as aerosols were eliminated from the atmosphere) but then dropped back down (as additional greenhouse gases were eliminated). This transition period wouldn’t be fun, but at least it would be short. See the light blue line in the graph below:

We’re still making an implicit assumption, though. By looking at the graphs of constant global average temperature and saying “Look, the problem doesn’t get any worse!”, we’re assuming that regional temperatures are also constant for every area on the planet. In fact, half of the world could be warming rapidly and the other half could be cooling rapidly, a bad scenario indeed. From a single global metric, you can’t just tell.

A team of researchers led by Nathan Gillett recently modelled regional changes to a sudden cessation of CO2 emissions (other gases were ignored). They used a more complex climate model from Environment Canada, which is better for regional projections than the UVic ESCM.

The results were disturbing: even though the average global temperature stayed basically constant after CO2 emissions (following the A2 scenario) disappeared in 2100, regional temperatures continued to change. Most of the world cooled slightly, but Antarctica and the surrounding ocean warmed significantly. By the year 3000, the coasts of Antarctica were 9°C above preindustrial temperatures. This might easily be enough for the West Antarctic Ice Sheet to collapse.

Why didn’t this continued warming happen in the Arctic? Remember that the Arctic is an ocean surrounded by land, and temperatures over land change relatively quickly in response to a radiative forcing. Furthermore, the Arctic Ocean is small enough that it’s heavily influenced by temperatures on the land around it. In this simulation, the Arctic sea ice actually recovered.

On the other hand, Antarctica is land surrounded by a large ocean that mixes heat particularly well. As a result, it has an extraordinarily high heat capacity, and takes a very long time to fully respond to changes in temperature. So, even by the year 3000, it was still reacting to the radiative forcing of the 21st century. The warming ocean surrounded the land and caused it to warm as well.

As a result of the cooling Arctic and warming Antarctic, the Intertropical Convergence Zone (an important wind current) shifted southward in the simulation. As a result, precipitation over North Africa continued to decrease – a situation that was already bad by 2100. Counterintuitively, even though global warming had ceased, some of the impacts of warming continued to worsen.

These experiments, assuming an overnight apocalypse, are purely hypothetical. By definition, we’ll never be able to test their accuracy in the real world. However, as a lower bound for the expected impacts of our actions, the results are sobering.

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Cumulative Emissions and Climate Models

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As my summer research continues, I’m learning a lot about previous experiments that used the UVic ESCM (Earth System Climate Model), as well as beginning to run my own. Over the past few years, the UVic model has played an integral role in a fascinating little niche of climate research: the importance of cumulative carbon emissions.

So far, global warming mitigation policies have focused on choosing an emissions pathway: making a graph of desired CO2 emissions vs. time, where emissions slowly reduce to safer levels. However, it turns out that the exact pathway we take doesn’t actually matter. All that matters is the area under the curve: the total amount of CO2 we emit, or “cumulative emissions” (Zickfeld et al, 2009). So if society decides to limit global warming to 2°C (a common target), there is a certain amount of total CO2 that the entire world is allowed to emit. We can use it all up in the first ten years and then emit nothing, or we can spread it out – either way, it will lead to the same amount of warming.

If you delve a little deeper into the science, it turns out that temperature change is directly proportional to cumulative emissions (Matthews et al, 2009). In other words, if you draw a graph of the total amount of warming vs. total CO2 emitted, it will be a straight line.

This is counter-intuitive, because the intermediate processes are definitely not straight lines. Firstly, the graph of warming vs. CO2 concentrations is logarithmic: as carbon dioxide builds up in the atmosphere, each extra molecule added has less and less effect on the climate.

However, as carbon dioxide builds up and the climate warms, carbon sinks (which suck up some of our emissions) become less effective. For example, warmer ocean water can’t hold as much CO2, and trees subjected to heat stress often die and stop photosynthesizing. Processes that absorb CO2 become less effective, so more of our emissions actually stay in the air. Consequently, the graph of CO2 concentrations vs. CO2 emissions is exponential.

These two relationships, warming vs. concentrations and concentrations vs. emissions, more or less cancel each other out, making total warming vs. total emissions linear. It doesn’t matter how much CO2 was in the air to begin with, or how fast the allowable emissions get used up. Once society decides how much warming is acceptable, all we need to do is nail down the proportionality constant (the slope of the straight line) in order to find out how much carbon we have to work with. Then, that number can be handed to economists, who will figure out the best way to spread out those emissions while causing minimal financial disruption.

Finding that slope is a little tricky, though. Best estimates, using models as well as observations, generally fall between 1.5°C and 2°C for every trillion tonnes of carbon emitted (Matthews et al, 2009; Allen et al, 2009; Zickfeld et al, 2009). Keep in mind that we’ve already emitted about 0.6 trillion tonnes of carbon (University of Oxford). Following a theme commonly seen in climate research, the uncertainty is larger on the high end of these slope estimates than on the low end. So if the real slope is actually lower than our best estimate, it’s probably only a little bit lower; if it’s actually higher than our best estimate, it could be much higher, and the problem could be much worse than we thought.

Also, this approach ignores other human-caused influences on global temperature, most prominently sulfate aerosols (which cause cooling) and greenhouse gases other than carbon dioxide (which cause warming). Right now, these two influences basically cancel, which is convenient for scientists because it means we can ignore both of them. Typically, we assume that they will continue to cancel far into the future, which might not be the case – there’s a good chance that developing countries like China and India will reduce their emissions of sulfate aerosols, allowing the non-CO2 greenhouse gases to dominate and cause warming. If this happened, we couldn’t even lump the extra greenhouse gases into the allowable CO2 emissions, because the warming they cause does depend on the exact pathway. For example, methane has such a short atmospheric lifetime that “cumulative methane emissions” is a useless measurement, and certainly isn’t directly proportional to temperature change.

This summer, one of my main projects at UVic is to compare what different models measure the slope of temperature change vs. cumulative CO2 emissions to be. As part of the international EMIC intercomparison project that the lab is coordinating, different modelling groups have sent us their measurements of allowable cumulative emissions for 1.5°C, 2°C, 3°C, and 4°C global warming. Right now (quite literally, as I write this) I’m running the same experiments on the UVic model. It’s very exciting to watch the results trickle in. Perhaps my excitement towards the most menial part of climate modelling, watching as the simulation chugs along, is a sign that I’m on the right career path.

What Happened At Durban?

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Cross-posted from NextGen Journal

Following the COP17 talks in Durban, South Africa – the latest attempt to create a global deal to cut carbon emissions and solve global warming – world leaders claimed they had “made history”, calling the conference “a great success” that had “all the elements we were looking for”.

So what agreement did they all come to, that has them so proud? They agreed to figure out a deal by 2015. As James Hrynyshyn writes, it is “a roadmap to a unknown strategy that may or may not produce a plan that might combat climate change”.

Did I miss a meeting? Weren’t we supposed to figure out a deal by 2010, so it could come into force when the Kyoto Protocol expires in 2012? This unidentified future deal, if it even comes to pass, will not come into force until 2020 – that’s 8 years of unchecked global carbon emissions.

At COP15 in Copenhagen, countries agreed to limit global warming to 2 degrees Celsius. The German Advisory Council on Global Change crunched the numbers and discovered that the sooner we start reducing emissions, the easier it will be to attain this goal. This graph shows that if emissions peak in 2011 we have a “bunny slope” to ride, whereas if emissions peak in 2020 we have a “triple black diamond” that’s almost impossible, economically. (Thanks to Richard Sommerville for this analogy).

If we stay on the path that leaders agreed on in Durban, emissions will peak long after 2020 – in the best case scenario, they will only start slowing in 2020. If the triple black diamond looks steep, imagine a graph where emissions peak in 2030 or 2040 – it’s basically impossible to achieve our goal, no matter how high we tax carbon or how many wind turbines we build.

World leaders have committed our generation to a future where global warming spins out of our control. What is there to celebrate about that?

However, we shouldn’t throw our hands in the air and give up. 2 degrees is bad, but 4 degrees is worse, and 6 degrees is awful. There is never a point at which action is pointless, because the problem can always get worse if we ignore it.

What Can One Person Do?

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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.

An Unmeasured Forcing

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“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

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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.

The Rest of the World

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Here in North America, we are surrounded with rhetoric denouncing the feasibility of climate change mitigation. It’s not possible to reduce our emissions, people say. It’s not worth it.

The situation in the U.S. Congress regarding this issue is becoming so bizarre that hopes for an international agreement to reduce greenhouse gas emissions have grown faint. Without the U.S. on board, many countries (see: Canada) will bail out entirely.

Not all countries are waiting for everyone else, however. Many developed countries, particularly in Europe, have gone ahead and achieved significant cuts in their emissions. Let’s take a step out of the little bubble of North America and see what the rest of the world managed to do while we bickered about whether or not there was even a problem.

***

Countries: the European Union (EU), representing most of Europe

Emission Targets: 20% below 1990 levels by 2020

How They’ll Get There: The EU started a cap-and-trade system in 2005. They also plan to target energy efficiency and develop the use of renewable energy.

How They’re Doing : The total emissions of the EU have declined slightly since 1990. This is partly because many Eastern European countries are still transitioning from communism, and their emissions are fairly low while their economies recover. However, some rich countries such as Germany, Sweden, Denmark, and the UK have made significant cuts in their emissions, and, as of 2008, were already around 10-20% below 1990 levels.

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Country: the United Kingdom (UK)

Emission Targets: 12.5% below 1990 levels by 2012, as per their Kyoto targets. Through their Climate Change Acts, the UK has also set a goal of 80% below 1990 levels by 2050.

How They’ll Get There: The government is aiming for 40% of their energy to come from low-carbon sources (both renewable and nuclear). They are also focusing on efficiency, and planning a cap-and-trade system.

How They’re Doing: The UK is well on track to meet, and even exceed, their Kyoto agreements. By 2010, their emissions were predicted to be 11% below their Kyoto targets.

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Country: Norway

Emission Targets: Norway has some of the most ambitious targets in the world. Not only are they aiming for emissions to be 30% below 1990 levels by 2020, they are planning a carbon-neutral economy – 100% cuts – by 2050. If a major international agreement comes to pass, like Copenhagen was supposed to be, they will pledge for carbon neutrality by 2030.

How They’ll Get There: In addition to their cap and trade system, Norway is investing a lot of money into carbon capture and storage (CCS). They have also introduced taxes on natural gas and stricter efficiency standards for new houses.

How They’re Doing: Norway’s emissions have increased by 8% since 1990. Hopefully their extensive plans will reverse that trend.

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Country: Australia

Emission targets: If an international agreement comes to pass, Australia will reduce their emissions to 25% below 2000 levels by 2020. Otherwise, they will shift that target to 5-15%. Normally, using a baseline that’s later than the standard 1990 is a warning sign, a clever trick that governments use to make their targets look stricter than they are (see: Canada). However, since Australia’s emissions fell slightly between 1990 and 2000, the equivalent target with respect to 1990 is actually more than 25%.

How They’ll Get There: The Australian Parliament has had difficulty passing cap-and-trade legislation. They are hoping to implement this eventually, but will focus on energy efficiency and renewables in the mean time.

How They’re Doing: Originally, Australia refused to sign Kyoto, but in 2007 a new Prime Minister, Kevin Rudd, was elected. He committed the country to Kyoto targets, just a little late. So far, it looks like Australia will easily meet their targets of 8% over 1990 levels by 2012.

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Country: Japan

Emission targets: Japan has set solid targets of 25% below 1990 levels by 2020, and 80% by 2050.

How They’ll Get There: Japan has a cap-and-trade system, and is considering a carbon tax. They also want 10% of their energy to come from renewables by 2020.

How They’re Doing: Japan’s emissions have increased slightly since 1990. As of 2008, they were about 6% above 1990 levels.

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Country: Canada

Emission targets: The Canadian government has pledged to reduce emissions to 17% below 2005 levels by 2020. However, emissions in 2005 were quite a bit higher than they were in 1990. When you adjust this estimate to the standard baseline, it’s actually a 2.5% increase. The Environment Canada website describes this as an “ambitious target”. Go figure!

How They’ll Get There: So far, the Canadian government has tightened up fuel efficiency standards for passenger vehicles, but that’s about it. The current administration refuses to consider meaningful action until the United States does. In fact, the House of Commons recently passed a bill setting meaningful emission targets (20% below 1990 levels by 2020, and 80% by 2050)…but the Senate, which has a Conservative majority, voted the bill down with absolutely no debate. Given the fact that Senators are appointed by Prime Ministers, not elected by citizens, it’s hard to see this action as anything less than anti-democratic.

How They’re Doing:By 2008, Canadian emissions had soared to 24% above 1990 levels.

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This data almost makes me feel ashamed to be Canadian, to be a part of such an obstructionist country. Look at what countries in Europe have managed to do. It wasn’t impossible, like so many North American politicians warned. And then look at countries like the United States and Canada, that have not only failed to reduce their emissions, but have actively worked against any kind of a plan to do so.

Future generations will not look on us kindly. We will become the villains of our own history books.

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Update: By popular request:

Country: United States of America

Emission targets: None

How They’ll Get There: Despite not having a formal target for emissions, the Environmental Protection Agency (EPA) began to regulate emissions from fossil-fuel fired power plants and refineries in late December. The Republican Party is resorting to all sorts of silliness to try to change this.

How They’re Doing: As of 2008, US emissions were 14% above 1990 levels.

Ozone Depletion and Climate Change

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“Global warming…doesn’t that have something to do with the ozone?” Well, no. Environmental issues are not all the same. It’s common for people to confuse climate change and ozone depletion, but they are separate issues – although they are indirectly connected in some interesting ways.

Ozone, which is made of three oxygen atoms stuck together (instead of two, which is what normal oxygen gas is made of), is vital to life on Earth. It forms a layer in the stratosphere, the second layer up in the atmosphere, that is very good at absorbing ultraviolet (UV) radiation from the Sun. UV radiation severely damages organisms if enough of it reaches the surface. The 3% or less that gets through the ozone already gives us sunburns and skin cancer, so you can imagine what the situation would be like if the ozone layer wasn’t there at all.

In the middle of the 20th century, synthetic gases known as chlorofluorocarbons (CFCs) became popular for use in refrigerators and aerosol products, among other applications. They were non-toxic, and did not react easily with other substances, so they were used widely. However, their chemical stability allowed them to last long enough to drift into the stratosphere after they were emitted.

Once in the stratosphere, the CFCs were exposed to UV radiation, which was able to break them down. Free chlorine atoms (Cl) were liberated, a substance that is very reactive indeed. In fact, Cl acts as a catalyst in the decomposition of ozone, allowing two ozone molecules to become three oxygen molecules, losing their UV absorbing power in the process. Since catalysts are not used up in a reaction, the same Cl radical can continue to destroy ozone until it reacts with something else in the atmosphere and is removed.

Over the poles, the stratosphere is cold enough for polar stratospheric clouds (PSCs) to form. These PSCs provided optimum conditions for the most reactive chlorine gas of all to form: ClO (chlorine monoxide). Now there wasn’t just a catalytic cycle of free Cl radicals depleting the ozone, there was also a cycle of ClO. It turns out that Antarctica was more favourable for ozone depletion than the Arctic, both because its temperatures were lower and because its system of wind currents prevented the ozone-depleting substances from drifting out of the area.

Before long, there was a hole in the ozone layer over Antarctica (due to the PSCs), and concentrations were declining in other locations too (due to the basic Cl reactions). The issue became a frontier for scientific research, and scientists Crutzen, Rowland, and Molina won the 1995 Nobel Prize in Chemistry for their work with atmospheric ozone.

In 1987, politicians worldwide decided to ban CFCs under the Montreal Protocol. This movement was largely successful, and the use of CFCs has become nearly negligible, especially in developed nations. They have been replaced with gases that safely decompose before they reach the stratosphere, so they don’t interfere with ozone. The regulations are working: the ozone hole in Antarctica has stabilized, and global stratospheric ozone concentrations have been on the rise since 1993.

In contrast, climate change is a product of greenhouse gases such as carbon dioxide. Unlike CFCs, most of them are not synthetic, and they are released from the burning of fossil fuels (coal, oil, and natural gas), not specific products such as refrigerators. Rather than destroying a natural process, like CFCs do, they strengthen one to the point of harm: the greenhouse effect. This phenomenon, which traps heat in the atmosphere, is absolutely vital, as the Earth would be too cold to support life without it. Increasing the concentrations of greenhouse gases with fossil fuels becomes too much of a good thing, though, as the greenhouse effect traps more heat, warming the planet up.

Just a few degrees Celsius of warming can cause major problems, as agricultural zones, wind and ocean currents, and precipitation patterns shift. The sea level rises, submerging coastal cities. Many species go extinct, as the climate changes faster than they can adapt. Basically, the definition of “normal” in which our civilization has developed and thrived is changing, and we can’t count on that stability any more.

Unlike the Montreal Protocol, efforts to reduce greenhouse gas emissions have more or less failed. Fossil fuels permeate every part of our lives, and until we shift the economy to run on clean energy instead, convincing governments to commit to reductions will be difficult at best. It remains to be seen whether or not we can successfully address this problem, like we did with ozone depletion.

Although these two issues are separate, they have some interesting connections. For example, PSCs form in cold areas of the stratosphere. That’s why the ozone hole is over Antarctica, and not somewhere else. Unfortunately, global warming is, paradoxically, cooling the stratosphere, as a stronger greenhouse effect means that less heat reaches the stratosphere. Therefore, as climate change progresses, it will make it easier for the ozone depletion reactions to occur, even though there are fewer CFCs.

Additionally, CFCs are very strong greenhouse gases, but their use has drastically reduced so their radiative effects are of lesser concern to us. However, some of their replacements, HFCs, are greenhouse gases of similar strength. They don’t deplete the ozone, but, per molecule, they can be thousands of times stronger than carbon dioxide at trapping heat. Currently, their atmospheric concentrations are low enough that they contribute far less forcing than carbon dioxide, but it wouldn’t take a large increase in HFCs to put us in a bad situation, simply because they are so potent.

Finally, these two issues are similar in that ozone depletion provides a smaller-scale analogue for the kinds of political and economic changes we will have to make to address climate change:

  1. Unintended chemical side effects of our economy posed a serious threat to all species, including our own.
  2. Industry representatives and free-market fundamentalists fought tooth and nail against conclusive scientific findings, and the public became bewildered in a sea of misinformation.
  3. Governments worked together to find sensible alternatives and more or less solved the problem.

We’ve already seen the first two events happen with climate change. Will we see the third as well?

Legislating Scientific Truth

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Cross-posted from NextGen Journal

Scientific statements rely on uncertainty and error bars. If our understanding changes, the scientific consensus changes accordingly, in a more or less implicit manner. There’s no official process that needs to be followed to update our knowledge.

Laws passed by governments work in the opposite way. Official technicalities are paramount, and acknowledgements that the government’s understanding could be wrong are rare.

Why, then, are attempts to legislate scientific truth – an archaic practice to any reasonable person – becoming far more common in the United States?

One of the most early, and infamous, incidents of this manner occurred in 1897, when the government of Indiana attempted to legislate the value of pi (∏). The text of the bill, describing a circle, clearly says “the ratio of the diameter and circumference is as five-fourths to four”. If you do a bit of simple fractional algebra, this comes out to ∏ = 3.2, rather than 3.1415952…and so on. The scary part is that this bill passed the House without a single nay vote. Luckily, it was postponed in the Senate indefinitely.

More recently – in fact, just last month – Joe Read, a member of the Montana House of Representatives, penned a bill that is equally disturbing. Let’s take a look at what he is planning to turn into state law:

“The legislature finds:

(a) global warming is beneficial to the welfare and business climate of Montana;

(b) reasonable amounts of carbon dioxide released into the atmosphere have no verifiable impacts on the environment; and

(c) global warming is a natural occurrence and human activity has not accelerated it.”

At least ∏ = 3.2 was moderately close to the correct value. This bill, however, proclaims exactly the opposite of what the scientific consensus tells us. I would argue that it is even more dangerous. A fundamental constant that is 0.1 or so inaccurate could cause a couple buildings to fall down in Indiana, but a law that orders the government to believe the opposite of what the scientific community says – a law that outright denies any possibility of a problem which, if not addressed, will likely harm the citizens of Montana for generations to come – could cause political ripples leading to mass destruction.

It looks like a case of government officials burying their heads in the sand, refusing to acknowledge a problem because the solutions are politically problematic. The physical world, though, does not obey the Thomas Theorem, a sociological theory of self-fulfilling prophecies. No matter how passionately people like Joe Read believe that climate change is natural/nonexistent/a global conspiracy, the problem won’t go away. In fact, it’s more of an inverse prophecy: if enough politicians refuse to acknowledge the reality of climate change, no action will be taken to address it, and the problem will get worse. It doesn’t seem like Joe Read et al have thought through this line of logic, though. Peter Sinclair wittily describes their mindset as “[s]o simple. Just pass a law. Command the seas to stop rising.”

Dana Nuccitelli goes one step further, claiming “Republicans have decided that they can repeal the laws of physics with the laws of the USA”. In this instance, he is referring to a second, similar, bill that the Republican Party is attempting to pass, this time at the federal level. Basically, Republicans are desperate to prevent the Environmental Protection Agency (EPA) from regulating  greenhouse gas emissions – which they have the authority to do, under the Clean Air Act, as they can “reasonably be anticipated to endanger public health or welfare”.

There are two ways to take away this responsibility of the EPA. First, Congress could create a system of their own to control emissions, such as cap-and-trade or a carbon tax – both more capitalist than standard regulation. Republicans aren’t too chuffed about this option, as they don’t want to have to control emissions at all. So they are invoking desperate measures by choosing the second option: if greenhouse gases were found to no longer pose a danger, regulation by the EPA would be unnecessary.

Legitimately reaching this conclusion would call over a century’s worth of physics and chemistry into question. If they could actually do it, the Republicans would probably win a Nobel Prize. Apparently, though, they aren’t interested in legitimacy. The “Energy Tax Prevention Act of 2011”, by Members of Congress Fred Upton and James Inhofe, claims to overturn the EPA’s endangerment finding and, therefore, takes away their authority to regulate greenhouse gases. The justification for such an unusual scientific finding consisted of a couple of testimonies from climate change deniers, spouting out the usual long-debunked myths that scientists thought of, considered, and ruled out long before you and I even knew what global warming was. They offered no new information.

Ed Markey, the Representative from Massachusetts, took the opportunity to openly wonder what field of science Republicans will “excommunicate” next: will it be gravity, the heliocentric solar system, or special relativity? Watch and listen to his brief remarks. (Aside: I am amazed at how quiet and civil the House of Congress is. In Canada, Members of Parliament from opposing parties like to shout and pound their desks when others make speeches.)

http://www.youtube.com/watch?v=QHVrE1NTgxI&feature=player_embedded

The Democrats on the House Energy and Commerce Committee invoked amendments to this bill that, instead of repealing the scientific consensus, acknowledged it:

Congress accepts the scientific finding … that “warming of the climate system is unequivocal”; that the scientific evidence regarding climate change “is compelling”; and that “human-caused climate change is a threat to public health and welfare.”

Zero Republicans on the committee voted in favour of these amendments. Why am I not surprised?

I wouldn’t place these words of legislation in the same category as the others. Instead of saying “this is how the physical world works”, the amendments state, “we, as politicians, accept what our scientists tell us.” Most importantly, the Members of Congress aren’t trying to outsmart experts in a field in which they have no experience.

However, I agree with Henry Waxman, the Representative from California, who says that such amendments shouldn’t be necessary – not because they’re wrong, but because the “finding is so obviously correct”. To me, governments accepting what their scientists tell them is the null hypothesis. The idea of politicians stamping down ideas that they don’t like, by attempting to legislate scientific truth, seems unspeakably bizarre. How did the most powerful and developed nation in the world reach this point?

Technology as Communication

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The relationship between technology and climate change is complex and multi-faceted. It was technology, in the form of fossil fuel combustion, that got us into this problem. Many uninformed politicians hold out hope that technology will miraculously save us in the future, so we can continue burning fossil fuels at our current rate. However, if we keep going along with such an attitude, risky geoengineering technologies may be required to keep the warming at a tolerable level.

However, we should never throw our hands in the air and give up, because we can always prevent the warming from getting worse. 2 C warming would be bad, but 3 or 4 C would be much worse, and 5 or 6 C would be devastating. We already possess many low-carbon, or even zero-carbon, forms of energy that could begin to replace the fossil fuel economy. The only thing missing is political will, and the only reason it’s missing, in my opinion, is that not enough people understand the magnitude and urgency of the problem.

Here is where technology comes in again – for purposes of communication. We live in an age of information and global interconnection, so ideas can travel at an unprecedented rate. It’s one thing for scientists to write an article about climate change and distribute it online, but there are many other, more engaging, forms of communication that harness today’s software and graphic technologies. Let’s look at a few recent examples.

Data clearly shows that the world is warming, but spreadsheets of temperature measurements are a little dry for public consumption. Graphs are better, but still cater to people with very specific kinds of intelligence. Since not everyone likes math, the climate team at NASA compressed all of their data into a 26-second video that shows changes in surface temperature anomalies (deviations from the average) from 1880 to 2010. The sudden warming over the past few decades even catches me by surprise.

Take a look – red is warm and blue is cool:

A more interactive visual expression of data comes from Penn State University. In this Flash application, you can play around with the amount of warming, latitude range, and type of crop, and see how yields change both with and without adaptation (changing farming practices to suit the warmer climate). Try it out here. A similar approach, where the user has control over the data selection, has been adopted by NOAA’s Climate Services website. Scroll down to “Climate Dashboard”, and you can compare temperature, carbon dioxide levels, energy from the sun, sea level, and Arctic sea ice on any timescale from 1880 to the present.

Even static images can be effective expressions of data. Take a look at this infographic, which examines the social dimensions of climate change. It does a great job of showing the problem we face: public understanding depends on media coverage, which doesn’t accurately reflect the scientific consensus. Click for a larger version:

Global Warming - the debate

Finally, a new computer game called Fate of the World allows you to try your hand at solving climate change. It adopts the same data and projections used by scientists to demonstrate to users what we can expect in the coming century, and how that changes based on our actions. Changing our lightbulbs and riding our bikes isn’t going to be enough, and, as PC Gamer discovered, even pulling out all the stops – nuclear power, a smart grid, cap-and-trade – doesn’t get us home free. You can buy the game for about $10 here (PC only, a Mac version is coming in April). I haven’t tried this game, but it looks pretty interesting – sort of like Civilization. Here is the trailer:

Take a look at these non-traditional forms of communication. Pass them along, and make your own if you’re so inclined. We need all the help we can get.