This is the script of a presentation I will make to several groups of high school students on Earth Day. I was originally going to use the same script from my PowerShift presentation, but in light of recent developments and my ever-expanding thoughts on climate change, I decided to create an entirely new presentation.

I would greatly appreciate any thoughts, input, suggestions, etc. Keep in mind that I don’t have my PowerPoint created yet, so some of the text may seem a little confusing without the visuals I’ll be pointing to.

Enjoy!

Update: Thanks for all the helpful comments and critiques. I’ve made some changes here, but feel free to keep them coming.

Welcome everyone, nice to see you all here. My name is Kate, I’m in my last year of high school, and I am here to talk to you about climate change, or global warming. After I graduate I want to be a climate scientist, so until then, I’m channelling my obsession into a website. For the past year, I’ve been writing the blog ClimateSight.org, which has allowed me to meet a lot of cool people and correspond with a lot of scientists.

I’ve spent several years doing a lot of research on climate change, and something that’s been really interesting to me is the link between climate scientists and the public – the communication between these two groups. And the very first thing I want to talk about is assessing credibility, which is probably the most important tool I can give you. How much weight should you give different statements from different sources about scientific issues?

The scientific community that is actually studying the issue is going to be more credible than the media and the public. And that scientific research starts with scientists. They write peer-reviewed articles, published in journals like Nature or Science. Anything that is a serious scientific idea will be in one of these journals at some time or other. But there are thousands of journal articles published every month, and because they’re generally studying the frontier of their field, it’s inevitable that some of them are going to be proven wrong later. That’s why there are scientific organizations and assessment reports that look back at all these papers and compile what we know about the major issues. So statements from organizations like NASA, or from assessment reports like the IPCC, means that something has stood the test of time.

Among all the people who are not scientists, some know more than others. People who communicate science, like journalists and high school teachers and some politicians, are held a little more accountable for what they say than just any random person on the street.

So let’s see what the different levels of the credibility spectrum say about global warming. Who would disagree – who would say that humans are not causing the Earth to warm? 0% of scientific organizations say no. Pretty much 0% of peer-reviewed articles say no – there is the odd one out there, but they’re so small in number that they round right down to zero. And less than 3% of publishing climatologists say no. But 57% of articles in leading newspapers say no (or probably not, or maybe, maybe not), and 53% of the public says no.

As you can see, there is a big gap right here. The top half of the credibility spectrum is very confident about human-caused global warming, and the bottom half is very confused. Why is this? How can an issue that is so important to public policy have such drastically different levels of support between those who study it and everyone else?

There are all kinds of common objections that you and I hear about global warming. What if it’s a natural cycle and we’re just coming out of an ice age? What if the Sun is heating up? And how could there possibly be global warming when it is so cold outside? There are all kinds of arguments against the idea of climate change that everybody knows. But the scientific community is still saying this. They are still sure that yes, it’s going on and yes, it’s us.

So there are three possible explanations. Scientists could be ignorant and overconfident. Maybe they never considered the idea it could be a natural cycle. Scientists could be frauds, part of some Communist conspiracy to take over the world somehow. Or, maybe scientists know what they’re doing, and have evidence to say what they’re saying. So let’s look at the evidence that they do have.

We’ve been studying this problem for a long time, and it all started in the 1800s, when the greenhouse effect was discovered – the gases in the atmosphere that trap heat and keep the planet warm enough for life. The idea that emissions of carbon dioxide from our burning of fossil fuels – like coal, oil, and natural gas – would eventually cause warming was first proposed in 1896. So this is not a new theory by any means.

We began measuring the carbon dioxide content of the atmosphere in the 1950s, and we can see that it’s steadily going up. Over the last 2.1 million years, CO2 never exceeded 300 ppm, but right now it’s at 390. This might not seem like a lot, but 390 ppm of arsenic in your coffee would kill you.

We can confirm that this increase in CO2 is due to human activity because of its isotopes. The carbon in CO2 from fossil fuels has fewer neutrons, on average, than CO2 from natural sources like volcanoes or the ocean. That makes it lighter, so we can tell the difference in samples from the air.

So we know that an increase in greenhouse gases causes warming, and we know that we are increasing greenhouse gases. So it’s not really a surprise that we’re starting to see the warming show up. There are five independent research teams worldwide that measure the average global temperature, some from weather stations and some from satellites, and all five of them are finding a very similar pattern of warming since about 1975.

But what if it’s a coincidence? What if something else was causing the warming, and it just happened to be at the same time that we were dumping fossil fuels into the air? Something that a lot of people don’t know is that there are ways that we can confirm that the warming is caused by us. First of all, there’s nothing else going on that could be causing it. Actually, if you took human activity out of the picture, we would be slowly cooling: the cycles of the Earth’s orbit show that we should be very very slowly going into a new ice age.

There is also a specific pattern of warming we can look at. If warming were caused by the sun, the entire atmosphere would warm in a uniform fashion. But if greenhouse gases were causing global warming, the first layer of the atmosphere (the troposphere) would be warming, but the next layer up, the stratosphere, would be cooling. This is referred to as the “fingerprint” of greenhouse warming, because it’s like DNA evidence or the smoking gun. And that’s exactly what we’re seeing – stratospheric cooling. (Randel et al, 2009).

So we can be very sure that yes, our activities are causing the Earth to warm, at a rate that we haven’t seen for at least the past 55 million years, which was before humans even existed. That’s really the problem – the rate of change. It’s not the actual temperature that poses a threat, it’s all about how much it changes and how fast. The world has been plenty warmer than this at times, like when dinosaurs were around. And dinosaurs were okay with that because it had been like that for a really long time and they had adapted to it. But a change in temperature at the rate we’re seeing now? It might seem slow to you and me, but on a geological timescale, it’s incredibly quick, too quick for species – including humans – to adapt. Yes, the climate has changed many times before, but it never really ended well.

For example, the largest extinction in our Earth’s history, the Permian extinction 250 million years ago, was most likely caused by warming from greenhouse gases that came out of supervolcanoes much larger than anything we have today. It got so warm that the ocean couldn’t hold any oxygen and produced hydrogen sulphide instead. That’s what makes rotten eggs smell bad, and it’s actually poisonous in large enough quantities. It killed 97% of species in the ocean and 70% of species on land. It has been nicknamed “The Great Dying”. So this is the absolute worst-case scenario of what can happen when too many greenhouse gases go into the atmosphere at once. It means a whole lot more than just nicer Winnipeg winters.

So, to the people who really look at this issue, the evidence is undeniable. In academic circles, there really is no argument. All the objections that we have – they thought of them long ago, and covered them all, and ruled all of them out, before you and I even knew what global warming was. 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.

As for the second option, that scientists are part of a conspiracy – if you stop and think about it, like, really? Scientific fraud happens, but on the scale of one paper, or at the most one scientist, not an entire field stretching back for over a century. Scientists are not that organized. And that only leaves one explanation – that the field of climatology does know what it’s doing, and does have evidence to say what it’s saying: that humans are causing the Earth to warm, and it’s not going to be good.

We’ve established that the top half of the credibility spectrum is the one that we can trust on this issue. So what’s going on in the communication between the top and the bottom so that the public has got totally the wrong idea? This is what I spend most of my time working on, and there are a lot of factors involved, but it really comes down to three points.

Firstly, climatology is a complex science, and it’s not a required course in high school, so the public doesn’t understand it the way they understand Newton’s Laws of Motion. Most people do not know all this stuff I just told you, and that’s only scratching the surface; there is so much more science and so many more lines of evidence. And when you only have bits and pieces of this story, it’s easy to fall prey to these kinds of misconceptions.

Second, there are, sadly, a lot of people out there trying to exploit number one. There are a lot of very prominent people in the media, politics, and industry who will use whatever they can get – whether or not it’s legitimate, whether or not it’s honest – as proof that global warming is not real. You’ll hear them say that all scientists said an ice age was coming in the 70s, so we shouldn’t trust them now. In reality, most scientists were predicting warming by the 70s, and the single paper to talk about an ice age was proven wrong almost immediately after its publication. You’ll hear them say that volcanoes emit more CO2 than humans, but volcanoes only emit about 1% of what we do. They’ll say that the Greenland ice sheet is getting thicker, so therefore, it cannot be warming. But the reason that Greenland is getting thicker is that it’s getting more snow, caused by warmer temperatures that are still below zero.

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 (Hoggan and Littlemore, 2009). 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.

The third reason that the public is so confused about climate change is that the media has been very compliant in spreading the message of these guys. You would expect that newspapers and journalists would do their research about scientific issues, and make sure that they were writing science stories that were accurate, but sadly, that’s not what’s happening.

One of the major problems is that 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 one day, because speed and availability of news has become more important than quality.

And, finally, when it comes to climate change, journalists follow the rule of balance, or presenting “two equal sides”, staying neutral, letting the reader form their own opinion. This works really well when the so-called controversy is one of political or social nature, like tax levels, a federal election, how we should develop infrastructure. In those cases, there is no real right answer, and people usually are split into two camps. But when the question at hand is one of science, there is a right answer, and some explanations are better than others. Sometimes the scientists are split into two equal groups, but sometimes they’re split into three or four or even a dozen. And 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 prove what they’re saying and nobody really takes them seriously. So framing these two groups as having equal weight in the scientific community is completely wrong. It exaggerates this extreme minority, and suppresses everyone else.

All these problems are perfectly explained by a man named James Hrynyshyn, a journalist himself. He says, “Science journalism….is too often practiced by journalists who know so little about the subject they’re covering that they can’t properly evaluate the reliability or trustworthiness of potential sources. The result is that sources with no credibility in the field routinely appear alongside genuine experts as part of an effort to provide balance.”

One of the best examples of how this kind of journalism can really go wrong happened quite recently. Someone hacked into the email server of the Climatic Research Unit in the UK, stole thirteen years of emails between scientists, sifted through them all to find the juiciest ones, and put them on the Internet. The police are trying to figure out who did this, because it’s quite illegal, but it wasn’t some teenage kid in their basement.

Some of the emails certainly were embarrassing, the scientists said some things that weren’t very nice and insulted some people. But can you imagine if all of your email was released to the world? Scientists are people too, and they say stupid stuff that they don’t mean over email just the same as you and I do – especially when there are so many people actively spreading lies about their work.

The most important thing, though, is that there was nothing in there that compromised any science, any data sets, anything that we know about climate change. Nothing actually changed…..but the scary part was that a striking amount of the media reported that the entire field of climate science was potentially a political scam.

For example, some scientists are working on reconstructing temperatures from before we had thermometers, using tree rings or ice cores or ocean sediment. In one of the most widely circulated emails, the scientists discussed how to “hide the decline” in a set of tree ring data that’s known to have some serious problems – the tree growth is going down while thermometers show local temperatures going up, which is the opposite of what you’d expect. It probably means there was a drought or something. So they were trying to see if they could still use the first part and cut out the useless part at the end. They’re only hiding it in a mathematical sense, they’re not hiding it from their colleagues or from the media. In fact, they’ve written about this decline in one of the most prestigious scientific journals in the world, so if they’re trying to pull off a conspiracy here, they’re not doing a very good job.

But somehow, in the media, the story changed. Instead of saying that scientists were “removing regional tree ring data known to be erroneous,” the media said they were “covering up the decline in global temperatures”. That’s so fundamentally different, so removed from the facts – these scientists don’t even work with global temperatures! – but you heard it everywhere. The story that reached virtually every newspaper in the world was that the world is cooling and scientists are trying to hide it from us.

That’s only one example of how a single phrase can be taken out of context and have its meaning completely twisted. It doesn’t surprise me, you see it from these guys all the time, but what absolutely amazes me is how the media just sat and lapped it right up without doing any research into the validity of these serious allegations.

Subsequently, two independent investigations into the contents of these emails have been released, and the scientists involved were basically cleared in both cases. The British Parliament found that “the focus on CRU has been largely misplaced”, that the scientists’ “actions were in line with common practice”, that “they were not part of a systematic attempt to mislead”, and that all of the CRU’s “analyses have been repeated and the conclusions have been verified”. (British House of Commons, 2010). The University of East Anglia found “no evidence of any deliberate scientific malpractice in any of the work of the CRU”, “no hint of tailoring results to a particular agenda”, and that “allegations of deliberate misrepresentation and unjustified selection of data are not valid”. (UEA, 2010) So this affirms what the climate science community already knew: the stolen emails do not change the science one bit.

But look at what newspapers told us for weeks on end. Every time the Winnipeg Free Press mentioned the emails, they would say something along the lines of, “The correspondence appears to suggest researchers may have manipulated data to exaggerate global warming.” These are very serious allegations to make, and they were made without evidence in serious, credible and widely read newspapers, and they’re not being retracted or corrected in the media now that the investigations are coming up clear.

Spencer Weart, who is a science historian, had some great words to say on this issue: “The media coverage represents a new low. There are plenty of earlier examples of media making an uproar without understanding the science….but this is the first time the media has reported that an entire community of scientists has been accused of actual dishonesty. Such claims….would normally require serious investigation. But even in leading newspapers like The New York Times, critics with a long public record for animosity and exaggeration are quoted as experts.”

Many of the scientists featured in the emails received death threats. Phil Jones, the director of CRU, says that he’s been suicidal. The story of these stolen emails is not a story of scientists engaged in conspiracy – it is a story of how desperate some people are to make it seem that way, and how gullible and irresponsible the mainstream media can be.

And not long after that, story after story broke that the IPCC, which is a huge UN publication about everything we know about the science of climate change, had all kinds of mistakes in it. So what were these mistakes? In 3 000 pages, two examples of overestimating climate change were found. First, the report said that the Himalayan glaciers would disappear by 2035, and we now know that it’s going to take a lot longer than that. Second, it said that 55% of the Netherlands is below sea level, when in fact 55% of the Netherlands is susceptible to flooding, and only some of that is below sea level. This last one is background information. It really isn’t all that relevant.

So should that have happened? No. But does it actually matter to our understanding of the science? No.

Then several British journalists managed to invent five or six other “IPCC scandals”. When these were investigated more seriously, they were found to be completely false. But they were still reported in virtually every newspaper around the world. Again.

However, the IPCC has made a lot of mistakes, much more serious than these, that none of the newspapers are reporting. The difference is that the mistakes that make the media scream scandal are examples of overestimating climate change, while the ones you don’t hear about are examples of underestimating climate change. There was recently a report published that evaluated the last IPCC report, and this is what it found:

Over the past three years, there was about 40% less Arctic summer sea ice than the IPCC predicted, and melting in the Arctic is far exceeding its worst case scenarios. Recent observed sea level rise is about 80% more than the IPCC predicted.  Global sea level by 2100 is expected to rise at least twice as much as the IPCC predicted. (Copenhagen Diagnosis, 2009)

So which seems more important? The exact date at which a specific glacier is expected to melt? Or the amount of sea level rise we can expect all over the world? I have yet to find a newspaper in the world that covered this, but I have yet to find a newspaper in the world that did not cover this. Yes, the IPCC makes mistakes, but they are almost always mistakes that say, “oops, it’s going to be worse than we thought.”

So, as you can see, the real message about the reality and severity of climate change is not getting through. Communication of science is always important, but it’s especially important for climate change, because it could potentially screw up our civilization pretty bad, and we want to minimize that risk.

Scientists, in general, are not that great at public communication – that’s why they’re scientists and not journalists or salesmen or whatever. They want to sit in the lab and crunch numbers. And there’s always been sort of a stigma in the scientific community against talking to the media or the public. But the one good thing about all these rumours and all this awful journalism is that it’s finally making the scientific community wake up and realize how bad things are and how much their voice and their input is needed.

In the period of just a few months, over 300 American climate scientists signed an open letter to the US government about how two small mistakes in the IPCC do not impact the overall message that humans cause climate change, and should not impact our efforts to stop it.

And the National Academy of Sciences, which is one of the most prestigious organizations in the world – 1 out of 10 members have a Nobel Prize – has all sorts of plans for public lectures and articles in newspapers and a science show on prime time television.

The one good thing about things getting this bad is that it makes the people involved mad enough to step up and finally try to stop it. To finally narrow this gap that has existed for so long. That’s why I’m here today, that’s why I’ve been writing my blog for over a year, because I’m mad, and if I don’t do anything about it my head is going to explode. I cannot just sit and watch while these rumours threaten our ability to preserve a good future for me and for us and for everyone who will come after us. And I sincerely hope that all of you will not just sit and watch it happen either. We need to fix this together.