What Exxon Knew

Clearly, there's going to be an impact so I'm not disputing that increasing CO2 emissions in the atmosphere is going to have an impact. It'll have a warming impact. How large it is, is very hard for anyone to predict and depending on how large it is then projects how dire the consequences are. In the fall of 2015, an investigation by the Pulitzer Prize winning Inside Climate News as well as the Los Angeles Times and the Colombia School of Journalism revealed a trove of documents from scientists inside oil giant ExxonMobil, showing that Exxon scientists understood the mechanisms and consequences of human caused climate change as early as the late 1970s and early 1980s. New York State Attorney General Eric Schneiderman recently subpoenaed oil giant ExxonMobil, apparently seeking documents that might show the company had downplayed the risks to profits and therefore to investors of stronger regulations on burning fossil fuels. The documents show Exxon understood a clear scientific consensus existed on the greenhouse effect, that the build-up of carbon dioxide in the atmosphere could become a serious problem and mentioned the distinct possibility of effects that could be catastrophic for a substantial fraction of the Earth's population.

Exxon scientists stated their research was in accord with the scientific consensus on the effect of increased atmospheric CO2 on climate. Multiple documents mentioned potential adverse impacts such as flooding of coastal land masses due to the melting Antarctica sheets. Our view of this very complex subject over the years, over the decades, has mirrored that of the broader scientific community. In the early 1980s, the scientific community was just beginning to sound the alarm about increasing buildup of gases like carbon dioxide in the atmosphere. Researchers say increasingly large amounts of CO2 are accumulating in the atmosphere. They fear the earth will gradually become warmer, causing as yet uncertain but possibly disruptive changes in the Earth's climate 50 to 70 years from now. The discussions that have taken place inside our company among our scientists mirror the discussions that have been taking place in the work that's been taking place by the broader scientific community.

That's what the facts show. Scientists and a few politicians are beginning to worry that global energy planning does not take the greenhouse effect seriously enough. Those same computer models correctly predict the past climate of the Earth. They correctly predict the present climate of the Earth. It is reasonable that they are correctly predicting the future climate on the Earth, given the amount of CO2 and other greenhouse gases that were pouring into the atmosphere. Internal briefing documents for Exxon executives showed a science effort that was on the very cutting edge for its time. Graphs showed projections of temperature rise derived from increasingly complex atmospheric models, much like temperatures that have now been observed in the real world. Using global climate models developed by NASA, Exxon scientists agreed with the mainstream projections of approximately 3 degrees global average temperature rise for a doubling of atmospheric carbon dioxide with a rise of more than 10 degrees projected for polar regions, a phenomenon called polar amplification, which has now been actually observed. Exxon state-of-the-art climate modeling predicted a pattern of planetary warming, projecting the lower atmosphere to warm, while the upper atmosphere cooled, a telltale fingerprint of human-caused warming that has now also been observed in the real world.

This table from 1982 predicts conditions looking well into the future including the current year of 2015 where Exxon predicted atmospheric carbon levels for our time to within nine parts per million and a temperature rise to within a few tenths of degree of the best current observations. But in the following years, something happened at Exxon. The company seem to have forgotten the findings of its own experts. Proponents of the global warming theory say that higher levels of greenhouse gases are causing world temperatures to rise and the burning fossil fuels is the reason. The scientific evidence remains inconclusive as to whether human activities affect global climate. You know, there was no doubt that fossil fuels were the main driver of higher CO2 emissions and that CO2 emissions will lead to the climate change, right.

What Exxon was trying to figure out in the 70s and 80s was, when is it gonna hit and how bad is it gonna be but they knew it was gonna be bad like they admitted it is going to be bad, they used the word 'catastrophic' over and over again in documents. Fifteen years later, as the science became more certain, Exxon backed away from that and Lee Raymond talked about that. Many scientists agree there's ample time to better understand climate systems and considered policy options so there's simply no reason to take drastic action now. It's a pretty startling walk back from what, you know, the scientists said 15 years earlier. What he's concerned about and wants to know, is whether Exxon was using one set of scientific models to do its work in the Arctic, for example, where Exxon has been engaged in drilling and on the other hand, telling the public, telling its shareholders a very different set of facts about the state of climate change.

When you're making public disclosures to investors and when you're making public disclosures to government officials, there are laws regulating whether or not that's something that you really need to stand by so if there's evidence demonstrating purposeful concealment and it's too early to say then it really could be a big cloud over the company site. Exxon has funded a number of organizations that he said have been openly climate change deniers, he mentioned the American Enterprise Institute… Take for example, this hold 97% of scientists agree on global warming. That is an utterly fraudulent number. Has Exxon been funding these organizations? Well, the answer is yes, and I'll let those organizations respond for themselves. They're basically saying you and your industry are hiding the risks of climate change just like the tobacco companies hid the risks of smoking.

.. and then using tactics that are very similar to what the cigarette industry or tobacco industry used for many years even though the overwhelming scientific consensus was that smoking cigarettes is bad for you, they would find a few scientists that would disagree and then they would say, look, scientists disagree so that's essentially how they would try to trick the public into thinking that smoking is not that bad. There are allegations that ExxonMobil also funded research from somebody for example at the Smithsonian Institution without disclosing and without that person disclosing that he was going on a certain path whereby there were other scientists within ExxonMobil that might have had beliefs to the contrary. You have received over a million dollars and funds from coal and oil interests. The last grant you received from a funder with no ties to the energy industry was in 2002. That's over a decade ago. In recent weeks, ExxonMobil has accused Columbia School of Journalism of ethical misconduct in reporting this story. In response, Steve Coll, the Dean of the Columbia School of Journalism, has refuted those allegations in a detailed letter since published in The New York Times.

Meanwhile, 2015 will soon go down in history as the hottest year globally in the modern record with indications that 2016 will be even warmer. We can't be a 100% sure, but which is more prudent? Which is wiser? …to do nothing and hope that a mistake has been made, or to take these predictions seriously even if there's a chance the precautions you will take will be unnecessary..

Environmental Econ: Crash Course Economics #22

Adriene: Welcome to Crash Course Economics. I’m Adriene Hill Jacob: And I’m Jacob Clifford. Economics is about choices, and how we use our scarce resources. It’s not just about producing and consuming, it can also be about conserving. Adriene: Maybe counterintuitively, economics has a lot to add to discussions of how we can balance our desire for prosperity and growth, with the need to protect our natural resources. Today we're going to look at environmental economics and think about how economics can help us keep our planet livable. [Theme Music] Pollution is going to happen, it’s a by-product of human existence and there is no way that we can get rid of it all. In fact, one of the ways we know about earliest the societies is by looking at their trash heap, something archaeologists call middens, because it sounds better than “dumps.” But the fact that humans produce all kinds of waste doesn’t mean that we have to embrace islands of trash floating in the oceans, a layer of smog over industrial cities, and toxic chemicals in our rivers. For sake of simplicity though, we’re going to focus on one type of pollution: carbon dioxide emissions. They’re one of the primary greenhouse gases.

These greenhouse gases basically blanket the earth and are causing climate change. CO2 levels are the highest they've been for millions years which is why environmentalists consider it a “planetary emergency.” There's a lot of effort going into how to remove greenhouse gases from the atmosphere, how to make cities more resilient to climate change, but in the interest of time we’re going to focus on efforts to reduce the amount of new pollutants getting spewed into our atmosphere. Jacob: The economic solution is pretty simple. Step one, identify the sources of the most air pollution. Done. We know exactly what it is. It’s factories that burn fossil fuels for energy, industries that use oil and coal to produce things, and vehicles with internal combustion engines. Step two, decrease the supply of these technologies and products or decrease the demand for them. That’s it, it’s simple.

But, the implementation of these policies gets complicated. Let’s look at decreasing supply. As we mentioned in the last video, one of the biggest problems with having countries independently enforce environmental regulations is the Tragedy of the Commons. No one owns the atmosphere, so there is very little incentive for countries to keep it clean and switch to expensive green technologies if no one else is going to. It’s not like there is some global environmental police punishing countries for polluting. While a country like Trinidad and Tobago has a huge carbon output per capita, its small population means it’s only producing a small fraction of global CO2. The other option is to decrease the demand for fossil fuels, possibly by finding alternate green energy sources. But we’re already very reliant on fossil fuels, and markets have made the production of those fuels very cheap. So, any new type of energy will have a hard time beating the established system.

So we can either wait patiently for new technologies to develop and get cheaper, or we can speed up the process by manipulating markets with government subsidies, taxes, and regulations. Adriene: In the case of pollution, there are long-term side effects, like climate change, that consumers often don’t take into account when they buy products. Remember negative externalities? When the full cost of a product doesn’t line up with the costs that manufacturers or consumers pay? Pollution represents a market failure — a situation where markets fail to produce the amount that society wants. To address this, some economists argue that government intervention is not only justified, but essential. There are all kinds of different ways intervention can happen — all of them meant to encourage producers and consumers to choose to pollute less.

One solution is for the government to come out and set very specific rules about how much specific industries can pollute. Forget markets. You're gonna follow our pollution rules. Another way governments encourage people to pollute less is by providing price incentives. Those incentives can encourage individuals to make choices that are better for the environment. The government could add taxes to gasoline purchases, or, on the other hand, provide subsidies for people who drive electric cars. Governments can also create permit markets — basically setting a limit on how much firms can pollute, and allowing those firms to buy and sell pollution permits. You’ve probably heard these called “cap and trade”. Proponents of cap and trade argue that it can successfully limit emissions, without creating hard and fast rules that might hinder economic growth.

And, governments can subsidize the development of a specific technology or industry—in an effort to make that technology more competitive with the alternatives. A country might help support the development of solar or wind energy. As of 2014, around 10% of the energy consumed in the United States came from renewable sources, which is pretty much in line with the global average. Current predictions are that by 2040 15% of the world energy consumption will come from renewable sources. But, alternative energy sources, for the most part, just aren’t cheap enough yet, so the majority of our energy is likely to continue to come from non-renewable sources, at least for now. Jacob: We don’t have the time to sit back and wait for new technologies to get cheaper, and there's no guarantee that the technologies that the government picks will be cost effective. Perhaps the solution is not to get rid of fossil fuels, but instead be more efficient with those fuels. But that has drawbacks, too. Some energy economists argue that the expected gains from energy saving technologies, are offset by something called the rebound effect. Let’s go to the Thought Bubble.

Adriene: Let’s say Hank uses a gallon of gas to drive to work everyday. Then, partially to help the planet but mostly to help his wallet, he buys a new fuel efficient car that only takes half a gallon of gas for the same commute. He saves money and there's less pollution. It is a win-win. But the rebound effect says that the benefits of energy efficiency might be reduced as people change their behavior. With the money he saves, Hank might start driving more than he normally would or he might go on a vacation in Hawaii. That leads to more consumption and possibly even more emissions. Also, if greater fuel-efficiency makes driving less expensive it might encourage more people to buy cars and increase the overall use of gasoline. And even if people didn't increase their driving, the new fuel efficiency could decrease the demand for gas, making fossil fuels cheaper and more readily available for other uses. The possibility of the rebound effect doesn’t mean we shouldn’t invest in energy saving technologies. It just means that we have to keep in mind how consumers will behave. It’s also the reason why it's important to have economists involved in the discussion of environmental policy.

The tools of economics can help analyze the incentives and figure out what might work best. Thanks Thought Bubble. Okay, so we’ve identified another problem. But before you get so angry that you kick over a barrel of oil and light it on fire, keep in mind that there is hope. Most countries are actively trying to address the problem of greenhouse gases. The international community has been trying for decades to work together to protect the environment with varying success. There are international treaties that commit countries to reducing greenhouse gas emissions. UN negotiations are underway to create a new climate change agreement — that could be adopted in December 2015. Private companies and governments are also funding research into green technology. In the U.S. the American Recovery and Reinvestment Act of 2009 allocated billions to fund renewable energy.

China is also vowing to clean things up, and, in fact, leads the world in renewable energy investment. So, now that most countries recognize there is a problem, the hope is that they’ll figure out a way, or more likely a lot of ways, to start addressing it. Environmental economists say that is not just governments and producers that need to change, it’s also consumers. Conserving and consuming more thoughtfully likely need to be a part of our daily lives if we want to protect the environment. But just bringing our reusable grocery bags to the store isn’t going to save the planet, even if it says it on the bag. Bigger and more costly interventions like improving insulation and changing thermostats might have more impact, but we need to recognize individual action alone isn’t going to be enough. Industries, governments, and individuals; we’re in this together. Thanks for watching, we’ll see you next week.

Crash Course Economics is made with the help of all these fine people. You can support Crash Course at Patreon, a voluntary subscription service where your support helps keep Crash Course free for everyone forever. And you get great rewards! Thanks for watching and DFTBA..

Kansas: Conservation, the “5th Fuel” (ENERGY QUEST USA)

Narrator: Kansas, a land of wheat, and corn, and cattle. In the heart of the country, it's number 48 out of all 50 states in energy efficiency. So this is a place where energy conservation can really make a difference. Come on, girls. Our region is a region of farmers. We are famously conservative and we have talked from the beginning about putting the conserve back in conservative. Narrator: According to a study by the Natural Resources Defense Council, improvements in energy efficiency have the potential to deliver more than $700 billion in cost savings in the U.S. alone. But, they say motivating consumers to take action is the key to unlocking this potential and that was the aim of Nancy Jackson's Climate and Energy project, with its Take Charge! Challenge. Kansans are patriotic, Kansans are hardworking, Kansans are humble.

Narrator: And Kansans are competitive. You all are competing against Ottawa, Baldwin City, and Paola, so really, you gotta beat those guys, yes? Do you want to help us beat Manhattan? Narrator: 2011 was the second year for the Take Charge! Challenge, a friendly competition among 16 communities arranged in four regional groups aiming to reduce their local energy use. Some of the lowest cost, most effective ways that you can take ownership of your energy future is taking ownership of the efficiency and the conservation of your house or your business. Narrator: Ray Hammarlund's office used federal stimulus dollars to fund four prizes of $100,000 for each of the four regions in the competition. Just as important as the grand prize, $25,000 went to each community to fund local coordinators who took the lead in galvanizing grassroots efforts.

Here's how the challenge worked in Iola. The challenge started in January of this year and ends October 1st. You're required to have three community events. We're going to have a lot more than that. Today, we are at the Fight The Energy Hog Festival. Becky Nilges: I love the hog. He was just so ugly that he is cute. He represents energy hogs in your home. You would probably let him in but you don't know the damage he's going to do. Narrator: Competing towns scored points by counting how many cfl bulbs and programmable thermostats were installed and how many professional home energy audits were done. Our job as energy auditors, both for commercial buildings as well as residential buildings is, we're essentially detectives.

What's happening here? Is there a great deal of air leakage? And we're finding that the majority of the houses that we're dealing with actually use a lot more energy than they need to. Narrator: In Lawrence, a house of worship did an energy audit, made changes, and got a pretty nice donation in its collection plate. David Owen: One part of the audit was to contact the power company. Well, during that process we discovered they had been overcharging us. And so we got a check, a rebate check from them for $4,456. Narrator: Other changes start small, but add up. We were a little bit worried at one point that the congregation would not accept the very bright, white type lights. So as an experiment, we took one of these chandeliers and changed all the bulbs in it to the cfls. And then we took the priest over here and we said, "which one did we do?" and he could not tell us.

So that told us it was ok to do them all. Narrator: Changing lights, adding insulation, and upgrading windows paid off. Even though it's an old building, we saved 64% on the consumption of energy in this room. Narrator: Lighting makes up about 15% of a typical home's electricity bill, and lighting all of our residential and commercial buildings uses about 13% of the nation's total electricity. But changing out old bulbs is a lot easier than paying for audits and the energy enhancements they recommend. Here's where the 2011 Take Charge! Challenge promised material assistance using stimulus funds. Ken Wagner: It's a $500 audit that costs you $100. The rest of that $500 is covered under the Take Charge Challenge program through the Kansas Energy Office. We really love the competitive spirit of the program and I think it's really raised a whole awareness of energy efficiency and the importance of energy efficiency to a lot of segments in our community here.

Narrator: Even Baldwin City bankers were grateful for financial assistance from state and federal governments. Dave Hill: Nine months ago, we installed a 14 KW solar power system. I believe the initial cost of the system was basically $65,000 and then we got a substantial grant from USDA, I believe it was $20,000. We have about $18,000 of our own money invested in the system, after all the deductions. We think it will pay out in about 7-8 years. Narrator: David Crane of NRG Energy thinks that kind of approach makes good business sense. Crane: What I say to every businessman who has a customer-facing business, think of a solar panel not only as a source of electricity, think of it as a billboard. You don't even have to write your name on it. Just put it on the top of your store and it will be sending a message to your customers that you're doing the right thing when it comes to sustainable energy. Narrator: Surveys of why conservation is hard to achieve have found that people want one-stop shopping, a place where they can find out what to do and get practical recommendations about who to hire and what it all might cost, just what this new facility was to offer.

Now it's mid-October, time for the results of the 2011 Take Charge! Challenge. MC: Fort Scott. MC: And the winner is Baldwin City. Nancy Jackson: Over 100 billion BTUs were saved as a result of this Challenge, and millions and millions of dollars in each community. Those savings come from measures that have been installed that will guarantee those savings for years to come. So the savings are enormous over time. $100,000 has a nice ring to it and it's a nice cash award for a community of our size. Our challenge now is to continue on with energy efficiency and encourage our community to save. Nancy: One of our real goals was to help people to stop thinking about energy efficiency as the things they shouldn't do, as what not to do, and think about it instead as a tremendous opportunity to both save money in the near term, and to make our electric system more resilient in the long term.

So it's about what we can do, both individually and together, and for us that feels like the real win. The United States today is twice as energy efficient as it was in the 1970s. And I think we have the capability in the decades ahead to become twice as energy efficient again. We believe this is something that can be done really anywhere with great success..

CO2, the Sun, and Warming in the Middle Ages – Viewer Questions on Climate Science

PAUL JAY: Welcome to The Real News Network. I’m Paul Jay in Baltimore. A few days ago we ran a couple of interviews with climate scientists, and in those interviews we promised that you, our viewers, could ask questions and challenge those scientists. And this is the beginning of a series where they will attempt to answer your questions. We’re also in the midst of our spring-summer fundraising campaign. So, in case you haven’t noticed, we have a $50,000 challenge grant. Every dollar you give triggers another dollar. And if you want us to keep doing Real News programming (as you know, ’cause you’ve heard me pitch this more than once), we need you to support us. We don’t accept government funding, we don’t accept corporate underwriting, we don’t sell advertising, which means it’s all about viewer support.

So there’s a “Donate” button over here. And if you click on it, it will help make sure we’re still here over the summer and heading into the U.S. elections. Now, with no further ado, we will invite our scientists to join us and we will start asking your questions. Now joining us from Paris is Valérie Masson-Delmotte. She’s a French paleoclimatologist. She holds an engineering degree from l’École centrale Paris in physics and fluid transfer. Since 1997 she’s been the senior scientist at the French Nuclear Energy Commission. She’s served on numerous national and international projects, including the Intergovernmental Panel on Climate Change. Thanks for joining us, Valérie. VALÉRIE MASSON-DELMOTTE: Hi. JAY: And also joining us–and, Jeff, before I go any further, you’re going to have to help me. I forget what city you’re in. KIEHL: [incompr.] Colorado. JAY: In Colorado.

Jeff Kiehl’s a senior scientist at the National Center for Atmospheric Research, where he heads the Climate Change Research Section. He’s published over 100 articles on the effects of greenhouse gases on the Earth’s climate, the effects of stratospheric ozone depletion on climate, and the effects of aerosols on the climate system. He’s also the coauthor of Frontiers of Climate Modeling. Thanks for joining us, Jeff. KIEHL: Thank you. JAY: So here’s how this format’s going to work. We’re going to ask one, maybe two questions per segment. We want to give our scientists time to dig into these issues. And we will do multiple segments. So, over the course of the next week or two during the fundraising campaign, we will be running more or less daily as we work our way through questions. And we will do it again.

Once you viewers have seen these series, I’m guessing you’re going to have more questions, more challenges. And then we’ll do it again, and we’ll keep doing it until we think we’ve kind of really dug into all these issues. Now, this part of this section is really about the science. Some of the questions we received were a little more political, and had to do with, you know, what are the real solutions and how are people going to pressure governments, like the American and Canadian government, that aren’t doing much of anything. We’re not going to deal with that now. We’re going to stick to science. And we may even find–our scientists may, in response to a certain question, may say that’s not their expertise, which is fair enough, ’cause this is about science, and if we do hit a question like that, then we will go find a scientist with that expertise and we’ll deal with the question then. So here we go.

We’re going to start, and I’m going to read these off my device here. So here’s the first question. Sorry. My first question–I just–I’m on an electronic thing, and it just moved. Okay. Here we go: The evidence does show a relationship between the rise in temperature and the rise in CO2. What it does not show is a cause-and-effect scenario that definitively proves that the temperature rises because of the rise of CO2. He, a viewer, writes: I know there’s a great temptation to jump the gun, since the evidence shows a relationship, but that is, again, bad science. And this is coming from–he identifies himself as WWVND, and he put this question up on YouTube. Okay. Valérie, you want to start, take the first shot at an answer? MASSON-DELMOTTE: Okay. So the question is about what is observed with regards to the timing of temperature changes and CO2 changes, and also about the methods that are used to relate these type of observations with causality. And there are a number of answers that could be brought in, depending on the timescales that are considered.

Once you look at the last centuries, one could look at spatial interglacial cycles or at geological past. My own expertise is focused on glacial-interglacial cycles. And most of you have already seen these curves showing a tight correlation between Antarctic temperature and atmospheric composition, CO2 concentration, methane concentration that is measured in Antarctic ice cores. And so this correlation is quite striking over the last 800,000 years. But if you look in detail, what you observe is that at the start of an ice age, Antarctic temperature is falling down before CO2 is going downwards. And if you look at the shift from a glacial period into a warm phase, at the moment we also think that there is lag for some of the time periods between the rise in Antarctic temperature and the rise in CO2. What’s interesting to consider on this timescale is what is the driver and what are the feedbacks. And the driver of glacial and interglacial climate changes, there is no doubt it lies in the incoming insulation that is distributed at the Earth’s surface.

And this distribution depends on the orbit of the Earth around the sun, so there are regular shifts in this orbit at timescales of 20,000 years, 40,000 years, 100,000 years. This changes the distribution of insulation. And that’s the main driver of glacial and interglacial changes. It acts on ice sheets and it acts on climate. And when climate is changing, especially ocean circulation is changing, then it controls, it regulates the amount of CO2 that is transferred from the deep ocean to the atmosphere. So on this timescale, CO2 is both a feedback to the impact of orbital forcing on climate, but it also acts on climate. And there is no doubt that when you add CO2 in the atmosphere, you alter the radiative properties of the atmosphere and it has an effect on climate. So in order to understand the exact role of CO2, you cannot just rely on data.

You need also to model the processes at play. So we use, basically, the same climate models that are used for present day for future projections. And we make tests with these models. What if you have constant CO2? What if we prescribe to these models the glacial and interglacial changes in CO2? And basically the answer is: you cannot explain ice ages with a constant glacial CO2. It doesn’t work. In order to explain quantitatively, but also the spatial patterns of glacial and interglacial changes, you need to take into account the effect of CO2. And the way climate models account for this effect seems correct at first order compared to their performance for glacial climates. So that’s an ongoing effort, in fact, in using data from glacial climate to test the realism of the sensitivity, that is, the response of climate to CO2 that is a result of numerous feedbacks simulated by climate models. JAY: Okay. Jeff, do you want to add something? And let me say that we’ve got a couple of questions I won’t read, but they’re similar, which is that CO2 is a naturally produced thing. The dead algae produces CO2, there’s all kinds of natural ways the Earth produces CO2, and there’s nothing wrong with CO2, and that nature has a way of dealing with CO2.

So maybe you can deal with that. Plus, do you want to add anything to what Valérie said? KIEHL: Yeah. So let me actually just start with the question you just posed about the sources, natural sources of carbon dioxide. Indeed, there are natural sources of carbon dioxide, and those processes or sources put enough carbon dioxide in the atmosphere that it’s actually very good that we have that carbon dioxide in the atmosphere, because left to its own, the natural processes supply enough carbon dioxide to the atmosphere that it keeps the planet’s surface warm enough for life to exist on earth. So this is actually the positive aspect of the greenhouse effect, that if we took all of the carbon dioxide out of the atmosphere that nature puts in without humans changing it, well, if we took all of it out, you can actually do a fairly simple calculation to show that the temperature of the Earth would drop a tremendous amount.

And what’s–also operates is–and as you start to drop the temperature by taking carbon dioxide out completely, the amount of water vapor also decreases in the atmosphere, and that cools the planet even more. So there have been some nice studies showing that carbon dioxide at its preindustrial levels is absolutely essential for life on Earth. The problem is, we humans are actually going in and changing the amount of carbon dioxide at a fairly substantial magnitude. For example, one natural source of carbon dioxide is volcanic activity, volcanoes. And, you know, you can think–most people think of volcanoes as explosive, but there are lots of volcanoes that aren’t exploding around the Earth, but they’re still leaking out carbon dioxide. So you can measure how much carbon dioxide’s coming out of volcanoes.

And people have done this, and they’ve compared how much volcanoes are putting into the atmosphere compared to humans. And it turns out that humans are putting hundreds of times more carbon dioxide in the atmosphere every year compared to what volcanoes are blowing. In fact, a recent calculation shows that within a period of 3 to 5 days, humans put more carbon dioxide in the atmosphere–more carbon dioxide in the atmosphere than volcanoes do in a whole year. So there’s–yes, nature does put carbon dioxide in the atmosphere, but when you actually add up the numbers and look at the hard facts, it’s clear that humans are outstripping nature now by orders of magnitude, factors of tens. JAY: I mean, one of the viewers wrote, in sort of a argument in support of what you’re saying, that nature produces CO2 and nature has ways of reducing CO2. Humans are adding to CO2 without reducing it. Is that a correct way to state it? KIEHL: Yes. Essentially, nature has–.

You know, if we weren’t on this planet (and we weren’t, you know, at one point in Earth’s history), the atmospheric carbon dioxide amount is basically regulated by how much is put into the atmosphere through volcanic activity and how much is taken out either in plants on land or organisms in the ocean, so-called ocean sink of carbon dioxide. And in the grand, long timescale of things, tens of hundreds of millions of years, because these processes work very slowly, that determines how much carbon dioxide is in the atmosphere. And it reaches a balance, unless, say, volcanic activity increases over a certain long period of time. And then what happens is carbon dioxide in the atmosphere increases. And guess what? We actually have examples of this in Earth’s deep past–we’re talking tens of hundreds of millions of years ago. And what we see is that when carbon dioxide was high in those past periods, the planet was much warmer.

It was so warm 30 million years ago that there was no ice on either Antarctica or Greenland. It was significantly warmer than it is today. And the amount of carbon dioxide in the atmosphere at that time was about 3 to 4 times what it is today. So–. JAY: Well, we actually–actually, let me just ask you–we have a question relating to that specifically. This is a question from–he calls himself silo cyberspace man. (We’ve got to get people to use their real names here.) But he asked the question that if 80 million years ago there was no ice on either of the poles, how are temperature and carbon levels determined from that time period? KIEHL: No, well, we have other ways of doing that. There are deep sediment cores in the ocean. People go out and–very brave people go out on boats in the middle of the ocean and they drop cores down into the sediments at the bottom of the ocean. And those sediments can take our climate record back 100 million years, or roughly. So they–using those, there’s geologic, geochemical information in those sediment cores that tells us about what the planet was like past the ice core record. And then if you go back even further, because the sediments at the bottom of the ocean can only take you back about 100 million years or so, if you want to go back further, then you have to go to the geologic record, the rock record.

And there you go out to the different places around the planet where you can date the geologic rocks and look at the formations of the rocks and the geochemistry of the rocks. And that again tells you something about what Earth’s climate was like even further back in time. So we have this array of techniques. The ice core records would go back about 1 million years, and then beyond 1 million years you use the sediment cores from the deeper parts of the ocean. And then, if you want to go back even further than that, you use the Earth’s geologic record. JAY: Right. Okay. We’re going to wrap up this segment. But if you want to respond or ask a question about this segment, please identify it in your email or in the comments section between the video so we can tie your comment to the specific segment, and then we can explore this issue even further.

So don’t forget this is all part of our matching fundraising campaign, and if you donate a dollar, we trigger another dollar. So please donate generously. And join us for the next segment of this further discussion on climate change science on The Real News Network..

Ocean Seeding – A New Technology that can Save Marine Life

People have relied on the abundance of the ocean since the beginning of human history. But things are rapidly changing. Scientists project that by 2048 the ocean will be depleted and fisheries will cease to exist. Billions of people rely on fish as their primary source of food and income – a number that will continue to grow over the next few decades as the world population increases. A collapse of ocean fisheries will be a massive threat to the food security and well-being of life on this planet. Nations around the world are pursuing better management practices and sustainable fishing in an attempt to curb this loss… but it is not enough. Despite our efforts, the health of the ocean is decaying even faster than initially predicted. Moreover, we have discovered that overfishing is only part of the problem. To see the bigger picture, we have to go much, much smaller. The whole oceanic ecosystem obtains its energy, food, and nutrients from tiny green phytoplankton – microscopic organisms that play a critical role as the base of the marine food chain. They grow and multiply through the absorption of sunlight – alongside water, carbon dioxide, and micronutrients such as iron.

Phytoplankton are the food of zooplankton, which in turn are consumed by small fish, which are themselves consumed by larger ones and so on. For their health, phytoplankton depend on the natural fertilization of iron-rich winds and upwelling currents, which have been ongoing for millions of years. However, as a result of climate change, winds and currents are changing, and the oceans are getting warmer. This hinders the mixing of surface layers, separating phytoplankton from the nutrients they need to grow. A NASA study has shown a constant decrease of phytoplankton in the ocean… 1% per year since 1950. That means plankton has declined more than 40% in just 60 years. When phytoplankton are in danger, the whole ocean is in danger. Less plankton means less food for fish and other organisms. With the continual decline of plankton, we are facing the collapse of the marine food chain as we know it due to climate change.

The question is: WHAT CAN BE DONE? Over the last several decades, scientists have observed that the iron-rich dust of volcanic eruptions can create massive plankton blooms over deserted areas of the ocean. On several occasions, scientists saw the volume of wild fish in these areas increase significantly – far beyond expectations. Given these observations, experts began to consider what might happen if humans could mimic natural volcanic iron fertilization to boost ocean life. This process is known as OCEAN SEEDING. In a recent Ocean Seeding project, researchers added iron dust to an area of the ocean that was part of the migratory route of juvenile salmon. Only a year later, mainland rivers experienced one of the largest salmon returns in history. Ocean Seeding offers an opportunity to begin repairing the damage to our ocean, rebuild wild fish stock, and improve food security for the growing populations of the world. This vital shift cannot be made without further research in Ocean Seeding and your support. Support us by sharing this video with your friends on social media.

And join the conversation on Twitter with hashtag #OceanSeeding.

The Crazy Plan to Capture and Store CO2 Under the Ocean

CO2 is created by every living thing on the planet, but also by burning fossil fuels, which is causing global warming… So, what if we just trapped it all under the ocean? That'd work, right? Howdy oxygenators, Trace here for DNews. Every breath you take, you'll be exhaling CO2. In fact, each exhale contains 100 times more CO2 than was inhaled, totalling about 2 lbs of CO2 per day, per person. Carbon Dioxide is odorless, colorless, highly toxic; and apparently tastes "pungent" and acidic. Because Earth is a relatively closed system, so carbon never leaves. It gets burned and then trapped and then breathed and reused all over the planet again and again. Most of us probably connect CO2 with breathing. While we only release pounds per day, industry releases tons, and if we don't capture it, the CO2 will continue to exacerbate the greenhouse effect.

In 2014 we were projected to release 37 gigatons of carbon dioxide into the air, which is more than the planet can absorb. This is getting serious. So, scientists are working on ways to filter and trap this ubiquitous gas. In the 1930s, researchers figured out if you bubble air through a solution of a derivative of ammonia called amine, the CO2 will be plucked out, "scrubbing" the air clean. We've since developed a bunch of other ways to capture it, but in 2014 MIT developed a super-efficient process using electrochemistry — electricity plus chemistry — it's awesome. The researchers used amines to pick up CO2, just like in the 1930s, but they added a modern twist. When you bubble polluted air through an amine solution those guys naturally want to cling to CO2. They love it. But then, electricity throws copper ions into the mix.

If you're an amine, copper ions are way more enticing than CO2, so they drop the toxic gas like a bad habit and pick up the copper. At that point the lonely CO2 floats out of the system! Yay! Afterward, the copper is pulled away from the amines who have to run through that process again and again. I sort of feel bad for the hard-workin' little guys, you know? But back to the CO2. So now that we've filtered it, then what? Well, because industry faces such strict penalties for releasing CO2 into the atmosphere, they've created Carbon Capture and Storage technologies. Essentially, most companies take the filtered CO2, cool it until the gas becomes a liquid, and then transport it somewhere for storage. There are two major ways to do this, one is straightforward, and one just seems crazy. The straightforward one is called geologic carbon sequestration. In the States, the US Geological Survey has identified 36 regions around the country where the CO2 could be injected into porous areas of rock between 3,000 and 15,000 feet underground (914-4600M).

And hopefully, there it will stay. The second CRAZY one, is similar, but it's oceanic carbon sequestration. In liquid form, CO2 is denser than water. So theoretically, if we just, pumped it under the ocean, the water above it would hold it down there like a weighted blanket. A 2013 study in Geophysical Research Letters looked at the viability of pumping liquid CO2 to the bottom of the ocean, and determined it would form a lake of liquid carbon dioxide. Yep. A lake. The high-pressure, cold world of the deep sea would hold it in stasis for perhaps 1,000 years. I know what you're thinking, and yes, both of the ideas have their dangers. For example in geologic sequestration the pressure of the rock above should keep the CO2 liquid and it should stay there. Should. But if the CO2 finds its way out of the rock… global disaster. In the undersea example, the implications are also dangerous. CO2 is toxic, remember, so it could drastically increase ocean acidity, and deep sea life might not survive. Plus, if it DID leak out… global catastrophe again. Look, there's no real, permanent solution to CO2 problems except maybe venting it into space somehow… or simply stopping the release of so much carbon.

Pollution doesn't just hurt the planet, it can also hurt YOU. Check out how in this video! And if you're down to listen to my weird voice, come subscribe to my podcast! On each episode we take 45 minutes to dig into a topic all the way to the brass tacks. Here's a taste Every time we talk about this stuff, I just want to never use fossil fuels again. What about you? Ever feel guilty about your carbon footprint? Tell me about it….

Attack on science

Hayhoe: These days, to get attacked, all we have to do is step foot off campus and tell anybody, even a local Kiwanis club, or a local church, or even a group of elementary school kids, that climate change is real, and then the angry letters start to flood in. Mann: Typically the attacks are not really about the science. The attack on the science is a proxy for what is really an effort to discredit science that may prove inconvenient for certain special interests. Oreskes: That’s when I started getting attacked. And that was when life sort of changed, it was a bit going through the looking glass. I started getting hate e-mail. What happened then was I mentioned to a couple of colleagues what was going on, and one of my colleagues at Scripps, at the Scripps Institution of Oceanography, said to me, “You should talk to Ben Santer.

Something sort of similar happened to him.” Santer: I remember sitting in a bar in Madrid with Stephen Schneider, the late Stephen Schneider, immediately after the final sentence had been agreed on in the 1995 report, a sentence that’s forever engraved on my memory. The balance of evidence suggests a discernible human influence on global climate. Here we are at this bar, and Steve says to me, “This changes everything, you know. Your life is going to be changed forever.” I had no idea what he was talking about. I really didn’t. Hayhoe: There is definitely a pattern of what happens: nasty e-mails, complaints to your university, requests for your e-mails, and a lot of attacks online. Mann: Often it takes the form of an attack on individual scientists. It’s part of the strategy of ad hominem attack.

Santer: Go after the scientist. Go after their integrity. Go after their funding. Make life miserable for them. Mann: I have received letters in the mail that in one case contained a while powder that I had to actually report to the FBI. They had to come to my office and investigate this and send this off to a lab to make sure that it wasn’t anthrax or some very dangerous substance that my entire department would have been subject to because of this. Santer: Then there’s the power of the Internet, which really was not available back in 1995, to harness your supporters to go after individual scientists, send them threatening e-mails or worse, and let them know, “We’re watching you. We don’t like you. We don’t like what you do.

” Mann: One of the tactics that you see in climate change denialism is an effort to spin and misrepresent peer reviewed scientific studies. So often studies that say one thing, for example, show that some aspect of climate change is even worse than we thought, will somehow be spun by climate change deniers as if it doesn’t provide evidence for concern. Oreskes: Clearly misrepresenting scientific information, cherry picking scientific data, one egregious example that we talk about in the book is an early work by Jim Hansen that Bill Nierenberg, Bob Jastrow and Fred Seitz take out of context and use it to argue that climate change is caused by the sun when, in fact, if you go back to the original paper, Hansen is arguing exactly the opposite. Santer: I think an additional weapon in the arsenal is Freedom of Information Act requests, which are being used not really to advance understanding or, again, shed light on complex scientific issues but as a tactic to threaten, to intimidate, to throw a spanner in the works to take up your time.

Mann: They will bully editors to try to get them to retract articles that are a threat to their case, their case being that climate change isn’t real, it’s not something to worry Oreskes: The weirdest day of my whole life practically was the day I got a phone call from a reporter in Tulsa, Oklahoma ,who said to me, “Are you aware of the fact that Senator James Imhofe is attacking you?” [laughter] I was like, at that time, I honestly didn’t know who Senator Imhofe was. In fact, I think I had been to Oklahoma maybe once but, I mean, and so I said, “No, I have no idea.” At first I thought he was making a mistake, this was some other, well, I have a very unusual name, so it didn’t seem plausible it was some other Naomi Oreskes. And then he had, he read to me from this speech that Imhofe was making and it was part of what we all are very familiar with now that I was a part of the “global conspiracy,” the scientific conspiracy to bring down global capitalism. And I remember thinking, “Conspiracy?!? Scientists are not that organised.” Santer: hacking e-mails, releasing them, all of these things. The technology has moved on since 1995, but it’s the same playbook: don’t really focus on the science and advancing understanding, contributing, but tear down, destroy.

Hayhoe: I think the best we can do is shield ourselves from the attacks and try not to dwell on them, unless it’s a safety issue, in which case we should take appropriate steps, and try to move on, focusing on what we want to achieve rather than what’s trying to hold us back. Mann: So if you are a prominent scientist, if you participate in the public discourse, as I’ve often said, you better develop a thick skin because you will be attacked personally. Hayhoe: My number one rule of thumb is: do not Google myself. I don’t want to see. My number two rule of thumb is to not read the comments section. I don’t want to know. Oreskes: One of the things that I think is really important us that by writing about these things and by documenting about it in a scholarly way with high standards of documentation, we can explain to our colleagues, our institutions, editors at journal, and the public and the media what this is. Because this is not a scientific debate.

I mean if I have one message that’s what my message has been all along and it still is: this is not a scientific debate; it’s a political debate. But it’s a political debate being made to look like a scientific debate. We now know why people do that. Because it’s a very very effective strategy because if you can make people think it’s a scientific debate then people will think it’s too soon to act. But if people see the truth, if they realise that this is a political debate, that it’s related to people’s ideologies to their values, structures, that gives a whole different cast. So it’s very very important for people to understand the character of what this thing is. Santer: Some things are worth fighting for. That perhaps was the most profound lesson for me back then: that a clear public understanding of the science, doing the kind of thing that you’re doing here, that was truly worth fighting for..

Carbon cycle

House: The carbon cycle is, very simply, it’s about the cycling of carbon through natural systems – through plants, through soils, through the ocean – and back out into the atmosphere. Le Quéré: In the natural carbon cycle, there’s a lot of fluxes of carbon dioxide, so the carbon goes in and out of the ocean, in and out of the terrestrial biosphere every year. House: The carbon is constantly flowing between these different systems and large amounts of carbon moves all the time. Le Quéré: I mean in the terrestrial biosphere, in the trees and the forests, it’s very easy to see. If you live in a place that has a forest area with seasons, you see in the winter the trees they have no leaves, and the spring comes and the leaves build up. This is all good carbon dioxide that goes in the leaves. And in the fall and in the autumn when the leaves fall down then their carbon is emitted back in the atmosphere.

So you have a huge signal there of CO2 going in and out of the atmosphere. House: So the ocean will take up the CO2, it dissolves in the surface of the ocean and also when the ocean will release CO2 to the atmosphere and that depends on the concentration of CO2 in the atmosphere and the concentration of CO2 in the ocean. And they form a balance with each other. There’s a continuous massive exchange of carbon dioxide between the atmosphere on land and the atmosphere on the ocean. That is roughly in balance until we introduce human change. Osborn: The experiment that we’re inadvertently perhaps conducting with the climate system is to move huge volumes of carbon from these stores undergrounds in the form of fossil fuels and bringing them to the surface and burning them and adding this carbon to the atmosphere. Le Quéré: What we’re doing now is putting everything out of balance, so we’re adding carbon to the atmosphere. It’s new carbon. It’s not part of the natural cycle.

It’s one that we’ve dug out of the fossil reservoir where they were stored, and we’ve put them back in the atmosphere. This is new carbon, and it puts the system out of balance. House: Although the human emissions are much smaller than the natural fluxes, the natural fluxes approximately are in balance and so they’re not causing an increase of carbon dioxide in the atmosphere. The human emissions, however are very rapid, and the natural systems don’t have time to respond to them. And so you get a net imbalance of raised carbon dioxide concentrations in the atmosphere. Lunt: It’s unequivocal that the amount of carbon dioxide in the atmosphere is increasing and is increasing fast and is increasing faster than ever. House: Oh the rate of change now is incredibly rapid, and what’s more it’s pushed us outside the bounds of what we’ve seen in terms of atmospheric concentration throughout the Ice Ages. Thompson: We have not had levels of C02 at 400 parts per million by volume in 800,000 years of history. House: In the Earth’s past throughout in and out of the Ice Ages, the concentration of CO2 in the atmosphere ranged between about 180 parts per million to 280 parts per mission.

And it took thousands of year for it to change between those states. The difference is now it’s gone up to 350 and even topping 400 parts per million on a single day basis. And that’s happened over a period of a couple hundred years. Friedlingstein: Every single generation is emitting more than the previous generation because emission of CO2 increased exponentially. We emit it so far, if you start from the beginning, which is like the industrial revolution in 1750 or something, when we start to burn fossil fuel, from that time up until today we emitted something like 2000 gigaton of CO2. More than half of this has been emitted over the last 50 years. Thompson: And we know where that CO2 is coming from because we do the isotopes of the carbon. We know it’s coming from fossil fuels. Le Quéré: So carbon is increasing in the atmosphere, but it doesn’t entirely stay there, so about half of the emission and maybe a bit more than half of the emission that we put in the atmosphere ends up in the natural environment. It ends up in the ocean and in the forest. Friedlingstein: For the carbon cycle today absorbed about half of the emissions we put in the atmosphere, so we emit, as I said, 40 gigaton of CO2 per year, about half of it, 20 gigaton of CO2 are taken back from the atmosphere by the land and by the ocean.

House: There’s a multitude of different processes that remove carbon dioxide from the atmosphere. So for example, CO2 from the atmosphere dissolves in the surface of the ocean and then that’s turned over and taken into the deep ocean. Really for that amount of CO2 to be completely removed from the atmosphere it has to be completely dissolved and go down into the deep ocean. And then we’re talking about geological timescales – so hundreds and thousands of years. Le Quéré: So what happens when we put carbon emissions into the atmosphere, new carbon from burning fossil fuel or from different station, what happens is this takes a long time for this carbon to readjust in the land and ocean. Eventually if we’re prepared to wait long enough, so that’s thousands of years, a lot of this carbon, maybe 70 percent will end up in the ocean, and the reason this takes time is that you have different adjustment times, so the CO2 goes in the surface ocean, it takes about 1 year to dissolve. But how it is transported from the ocean’s surface to the intermediate and to the deep ocean depends on the ocean circulation.

The ocean circulation takes hundreds to a thousand years to mix the entire ocean. That’s the timescale that is really relevant here is taking a molecule of CO2, we’ve put it in the atmosphere, how long is it going to take before it ends in the deep ocean? House: So about 65 to 80 percent of the carbon dioxide pulse that’s put into the atmosphere will be removed within about 2 to 200 years. The rest of it, the remaining 35 percent, will take between 2 and 20 millennia to be completely removed from the atmosphere. So roughly you have to think whatever we’re doing today, whatever CO2 is being emitted, roughly a third of it is going to stick around essentially forever really when you consider it in our lifetime. Pelto: We can’t change the atmosphere, the chemistry, with one of the main constituents carbon dioxide by 25 percent and expect nothing to happen. You change your diet by 25 percent. You decide you’re going to start consuming 25 percent more calories, and you don’t change your exercise or anything else. You can’t realistically expect nothing to happen. And that’s what you have to understand.

If we change fundamentally our atmosphere chemistry, we can’t expect climate to stay the same..

How Global Warming Works in Under 5 Minutes

You may have heard of global climate change, which is often called "global warming." Whether or not people accept that humans are causing global warming, most folks have an opinion about it. But how much do regular people understand the science of climate change? If you were asked to explain how global warming works, could you? Take a moment to try to explain to yourself how virtually all climate scientists think the Earth is warming. What is the physical or chemical mechanism? Don't feel bad; if you're anything like the people we've surveyed in our studies, you probably struggled to come up with an explanation. In fact, in one study we asked almost 300 adults in the U.S.– and not a single person could accurately explain the mechanism a global warming at a pretty basic level. This is consistent with larger surveys that have shown that people often lack knowledge about climate change.

But how can we make informed decisions without understanding the issues we're debating? Allow us to give you a short explanation of how global warming works: First, here is how Earth's temperature works without considering how humans influence it. The Earth absorbs light from the Sun, which is mostly visible light. To release that light-energy, Earth also emits light. But, because the Earth is cooler than the sun, it emits lower-energy infrared light. So, Earth's surface essentially transforms most to the visible light it gets from the sun into infrared light. Greenhouse gases in the atmosphere, such as methane and carbon dioxide, let visible light passed through, but absorb infrared light–causing the atmosphere to retain heat. This energy can be absorbed and emitted by the atmosphere many times before it eventually returns to outer space. The added time this energy hangs around has helped keep earth warm enough to support life as we know it.

Without this greenhouse effect–caused by these greenhouse gases in the atmosphere– the Earth's average surface temperature would be about 50 degrees Fahrenheit cooler, which is well below the freezing point for ice! So, how have humans change things? Since the dawn of the industrial age, around the year 1750, atmospheric carbon dioxide has increased by 40%– and methane has almost tripled. These increases cause extra infrared light absorption, meaning an extra greenhouse effect, which has caused Earth to heat above its typical temperature range. In other words, energy that gets to Earth has an even harder time leaving it, causing Earth's average temperature to increase– thus producing global climate change. In case you're wondering about what makes greenhouse gases special, here are two sentences of slightly technical information: Greenhouse gases such as carbon dioxide absorb infrared light because their molecules can vibrate to produce asymmetric distributions of electric charge, which match the energy levels of various infrared wavelengths.

In contrast, non-greenhouse gases such as oxygen–that is, 02–don't absorb infrared light, because they have symmetric charge distributions even while vibrating. To wrap, up we'll quickly summarize the mechanism global climate change: Earth transforms sunlight's visible energy into infrared light, and infrared energy leaves Earth slowly because it's absorbed by greenhouse gases. As people produce more greenhouse gases, energy leaves Earth even more slowly– raising Earth's temperature even more than it has already gone up. That's how global warming happens! This wasn't so hard to understand, right? In these few minutes you've hopefully become one of the few people who understand the mechanism of global climate change. Please share this video with others so you can help them understand how global warming works, too.

Thanks for listening!.

Making sense of the slowdown

The Earth’s climate is controlled by the energy balance at the top of the atmosphere. If more heat enters the atmosphere than leaves, then the planet warms. Adding heat trapping gases changes the balance, which in turn causes warming. Ocean heat measurements show that the planet is indeed absorbing heat. Despite this fact, it is often claimed that the global warming has stopped. This claim is inspired by evidence that warming of the atmosphere has been slower over the past one and a half decades. This slowdown is sometimes called the hiatus. However, there are other factors which affect the atmosphere over shorter periods. These can cause faster or slower warming of the atmosphere. To understand the slowdown in warming, we need to understand some of these factors.

If we look at the global surface temperature over the past 3 decades, there are big changes in temperature from year to year. We know the cause of some of these variations. One of the biggest is the El Nino cycle. El Nino is a phenomena in which heat is stored up in the western Pacific Ocean, and then released to the atmosphere in the eastern Pacific. This happens over the course of a few years. El Nino is not predictable, but we can track it in retrospect through sea surface temperature measurements. If we compare past El Nino cycles with temperature changes over the past three decades, we can see that there is a strong relationship between the two. El Nino years tend to be hot years. Recent years have been dominated by the cool phase of the cycle. This is responsible for some of the slowdown in warming. However, El Nino doesn’t explain everything. There are cooler periods in the early eighties and nineties which don’t fit the El Nino cycle.

These were caused by two major volcanic eruptions, El Chichon and Pinatubo. Dust from the volcanoes spread in the upper atmosphere, cooling the surface. Smaller eruptions happen all the time, but can also affect temperatures. There has been an increase in the number of small eruptions over the past few years, offsetting a bit of the greenhouse warming. Another factor is the solar cycle. Satellites tell us that the sun varies in brightness with the sunspot cycle. The last cycle has been particularly weak. A dim sun also offsets a little bit of warming. Yet another factor is pollution. Rapid industrialisation in Asia has led to more particulate pollution in the atmosphere, which also has a cooling effect. The final factor is in the observations themselves. Two of the major temperature data providers, the UK Met Office and NOAA, don’t include the Arctic in their global temperature calculation, because there are no weather stations there.

But the Arctic has been warming faster than anywhere else on the planet. Missing it out leads to an underestimation of the rate of warming. To recap, greenhouse gases have continued to grow over the last one and a half decades. But over the same period, volcanoes, the weak sun and pollution have had a cooling effect, and the rate of warming has been underestimated as well. Two recent studies have put all of these together. If we ignore the short term influences, climate models predict faster warming than we have observed. However, if we use global temperature estimates, and add the influence of El Nino, volcanoes, the weak sun and pollution into the models, then the agreement is good. What can we conclude from this? When we put everything we know into the models, the answers match what we observe. So the slowdown in warming makes sense in retrospect, and doesn’t give us a reason to doubt the models.

However, we couldn’t have predicted it in advance, because we can’t predict volcanoes, pollution or the sun. The slowdown in warming has created a whole family of myths with different levels of sophistication. At one extreme, it is possible to argue that the hiatus should reduce our estimates of climate sensitivity. This is a genuine scientific argument, although the analysis we have just seen suggests that no reduction is required. At the other extreme, it is sometimes claimed that the hiatus disproves the role of CO2 in global warming. They claim that CO2 has increased, but the world hasn’t warmed. This is an example of a strawman, and a complex cause fallacy. Climate science doesn’t claim that CO2 is the only factor which affects temperature. This is why the hiatus is so hard to deal with. The myths may be wrong, but they are simple and convincing. The complex cause fallacy exists because people like things to be simple, but explaining the complex drivers of climate is hard. But in the end, all the hiatus myths revolve around drawing attention away from the big picture. When we look at the big picture, the hiatus does not change our understanding of human caused global warming.

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