8.2: Stories

Stories are a wonderful way to engage an audience. Scientists are widely admired, scientific research has clearly brought many benefits to humanity, and you might naively think that most people would be inclined to accept the main findings of climate science. Yet many people, including “Uncle Pete,” a fictional character closely based on fact, strongly disagree with climate scientists. When Uncle Pete comes to dinner, he ruins the meal for everyone else by loudly proclaiming that climate scientists are dishonest or incompetent, and climate science is fraudulent or a hoax or simply incorrect. Pete insists on frequently repeating several climate myths and falsehoods, which he believes are true. He may have heard them on a talk radio show or seen them in some dark corner of the internet. Many people know a real person, perhaps a friend or colleague or family member, who closely resembles Uncle Pete.

Uncle Pete’s myths and falsehoods include claims such as the world isn’t warming; or the warming is natural and not human-caused; or volcanoes produce more carbon dioxide than people do. In a moment, I will explain why Uncle Pete’s favorite and most frequently repeated claims are simply wrong. I don’t have enough space to cover all of them, and I recommend the website https://skepticalscience.com for the rest of the story. That website is a collection of the most commonly heard climate myths, and why they are all dead wrong. Skepticalscience.com is a useful resource in refuting your own Uncle Pete. For up-to-date scientific information on climate change, I also highly recommend the website www.realclimate.org, which is run by excellent climate scientists. The main postings by these scientists on realclimate.org are usually outstanding, but the comments on the site by bloggers and other viewers vary greatly in quality.

Start with the myth that the warming we have observed in recent decades is natural and not human-caused. First, let’s be clear that the climate has indeed changed naturally in the past, with ice ages being an obvious example. But natural causes simply cannot explain the recent warming. How do we know that? It’s much like the story of wildfires, which can be caused naturally, by lightning. But they can also be caused by people, either by carelessness or by arson. As you know, wildfire experts can investigate after a wildfire and can frequently determine exactly what caused it. They know how to do the detective work.

We climate scientists are good detectives too. We have discovered what paces the ice ages. It is the slow changes in the Earth’s orbit around the sun, which affect how sunlight is distributed over the Earth’s surface in the different seasons. Over many thousands of years, these effects are strong enough to trigger the transitions between ice ages and the warmer periods between them. However, over short time periods, such as decades, the orbital changes have much too small an effect to produce the observed large warming that has occurred in recent decades.

Through this kind of research, we scientists have also quantitatively ruled out all the other natural processes known to affect climate. For example, the sun powers the entire climate system, and the amount of energy given off by the sun does vary. The biggest variation that has been measured on decadal time scales is only about 0.1%, and that variation is due to the 11-year solar cycle, often called the sunspot cycle. We can measure this decadal-scale energy variability very accurately, and we can demonstrate convincingly that the measured changes are much too small to have caused the observed warming. As for the claim that the extra carbon dioxide added to the atmosphere by human activities is tiny compared with the amounts produced by volcanoes, that too fails quantitatively. Measurements show that human activities, mainly burning coal and oil and natural gas, produce about 100 times more carbon dioxide than volcanoes do.

Thus, we humans have taken over the dominant role of deciding what the climate in coming decades will be. We are no longer passive spectators in the global climate change pageant. We have become the primary actors. To climate scientists, whose goal is to discover the truth about climate change, it really doesn’t matter whether or not some people find this discovery believable. Science is based on facts and evidence, not on beliefs. Most people have a very vague conception of what science is and what scientists do. People often recall their high school chemistry course, for example, as a boring exercise in memorizing useless things, like the periodic table of chemical elements, and then forgetting them as soon as possible after the exam. Most people have never met a scientist. It’s not just that people don’t know elementary facts, such as that the Earth goes around the sun once a year. It is that they have no idea how such facts were discovered. There is nothing wrong with belief; indeed, it’s important for people to believe that it is good to treat other people well. But in some domains, there is another way to find out what is true. That is to compare one’s beliefs with facts and evidence. Science is the name we give to doing that.

Science provides extremely persuasive evidence that the heat-trapping atmospheric gases and particles produced by human activities such as fossil fuel burning are the main cause of the warming observed in recent decades. This aspect of climate science is very firmly established, going back to definitive laboratory experiments in the 1850s. Those scientific experiments showed clearly that carbon dioxide and other gases, present in small quantities in the atmosphere, have powerful heat-trapping properties. In recent decades, the fingerprint of the observed warming, such as how it varies with altitude and geography and season, matches the pattern that we expect from human activities adding heat-trapping gases to the atmosphere. We have found the enemy. He is us. Figure 8.2.1 symbolizes the profound and disturbing truth that we people are now the main actors in climate change. Our choices will determine the future climate. The destiny of the planet is indeed in our hands.

Figure 8.2.1 The warming climate observed in recent decades is not natural. Human activities, such as extensive use of fossil fuels, are causing it. We people are now the main actors in climate change. The destiny of the planet is in our hands. Reproduced from clipartimage.com.

Here are some of Uncle Pete’s favorite myths and falsehoods.

Uncle Pete asks, How can you forecast climate for a century if you can’t even forecast the weather for next week? Answer: Climate is statistics, and that is much more predictable than daily weather, just as we can skillfully forecast mortality statistics for large populations, but not the lifetime of a specific person.

Pete claims that in the 1970s, climate scientists predicted global cooling. That’s simply not true. We’ve checked. Global cooling was prominent in some media articles and popular books, but not in the scientific research publications of the 1970s. The great majority of climate scientists in the 1970s were already focused on warming.

Pete has heard about certain satellite data that seemed to show a lack of warming. We have known for many years now that those data were simply wrong. Measuring atmospheric temperatures from satellites is technically very difficult. It took time to learn how to do it right.

Pete says changes in the sun cause climate change. That is true for some past climate changes but not for the warming observed in recent decades. We measure the sun and its variability. The effects of the sun’s changes in recent decades are tiny compared with effects caused by humans.

Pete claims that the atmospheric CO₂ amount increased from natural causes, like volcanoes. That’s just plain wrong. It did not. We can measure volcanic emissions. We also measure human-caused emissions. Human activities produce about 100 times more CO₂ than volcanoes do.

Pete says errors in the Intergovernmental Panel on Climate Change (IPCC) reports show that the science is wrong. Not true. A few small mistakes did get into the reports, but none of them is important.

All of Uncle Pete’s claims are simply not true. They are falsehoods, not facts.

There are similar convincing refutations of all the other common climate myths. That’s why many studies have shown that about 97% of the climate scientists who are most active in publishing research on climate change agree that the observed recent warming is real and serious and overwhelmingly human-caused. Nevertheless, Uncle Pete remains unconvinced. He continues to repeat the myths. You might well ask, Why is Uncle Pete so stubborn and so resistant to overwhelming scientific evidence? That’s a very good question, and here is my answer.

For many skeptics or contrarians, like Pete, the climate change issue is not a science topic at all. For Pete, climate change is simply an opportunity for the government, and for liberals and environmentalists, to make rules and regulations, to interfere with markets, and to diminish the personal freedom of individuals. For Pete, climate change is just one more excuse for the authority of the state to control the lives of citizens. This view of Pete’s has nothing to do with science, and no argument based only on science can change it. Uncle Pete, like some actual people I know, may seriously fear that the government will not only claim the right to decide what kind of car he will be allowed to drive, but will ultimately want to force him to limit his individual carbon footprint, that is, to ration his personal emissions of heat-trapping gases.

Uncle Pete invariably has a high opinion of the free market. He is confident that government actions, such as taxes and regulations, tend to hinder free markets and thus have the effect of limiting economic progress. He is also suspicious of subsidies for renewable energy. He is sure that renewables will never be feasible without big subsidies. Uncle Pete couches his opposition to carbon taxes or fees in statements such as “If you let people keep more of their money, they will invest it in the future.” Once again, science is irrelevant here, and no claim that science has discovered or proven this or that fact will change Uncle Pete’s mind.

Research showing that some 97% of active climate experts agree with the mainstream scientific consensus does not impress Uncle Pete. Instead, he is convinced that many climate falsehoods and climate myths are true. Uncle Pete may be a fictional character, but almost everybody seems to know people who closely resemble him. Some well-known public figures and some high officials in the government of the United States apparently agree with Uncle Pete. If you want to have any hope of changing the opinion of your own Uncle Pete, you need to understand why he rejects the science of climate change.

It’s sad but true that most Americans have never met a scientist. Uncle Pete may have his own somewhat strange ideas about how science works and what scientists do. Peer review, the elaborate and thorough formal process by which other scientists carefully evaluate new scientific research before it can be published in technical journals, carries no weight at all with Pete. In fact, he can easily imagine a corrupt and powerful scientific establishment, conspiring to deny research funding to scientists who disagree with prevailing opinions, and to prevent them from publishing. Pete likes to mention Galileo as an example of an outlier in science who turns out to have been correct. He forgets that real geniuses like Galileo are extremely rare and that almost everybody who considers himself a Galileo is very badly mistaken. Pete may cite past errors made by scientists as evidence that the scientific mainstream is indeed sometimes badly mistaken. Pete is very suspicious of us scientists, and he may think that government support of research in climate science is a waste of taxpayers’ money.

Social science tells us that people tend to trust those who share their values and to distrust those who do not. We know that controversial issues, such as abortion and evolution and gun control, bitterly divide the United States, and we ought to realize that climate change is a very big issue for Uncle Pete. His natural distrust of academics and elites generally is increased if he thinks climate scientists are arrogant people who are scornful of his opinions, who mock his values, and who dismiss his most firmly held convictions.

I urge each of you to engage with the Uncle Pete whom you may know. Have a civil conversation. In his heart, Uncle Pete would probably admit that everybody is entitled to his own opinions, but not to his own facts. When it comes to facts, we scientists have the high ground. The world is warming. It’s not a hoax. We measure it. The warming did not stop in 1998 or any other recent year. All the warmest years are recent years. The atmosphere is warming, and so is the ocean. Sea level is rising. Ice sheets and glaciers are shrinking. Rainfall patterns and severe weather events are changing. Climate change is real and serious, and it is happening here and now. It is definitely not caused by natural processes. Human activities are clearly the dominant cause of the climate changes we have observed in recent decades.

None of these facts tells us exactly what we should do about climate change. Science can inform wise policy, but it cannot decree or prescribe what the best policies will be. There is no silver bullet, but there is lots of silver buckshot. The main barrier to action is a lack of political will. In deciding climate policy, science matters, but so do values, priorities, and political convictions. Given the same facts, different reasonable people can easily prefer different policies. For Uncle Pete, attacking climate science and scientists is simply a disguise for what really concerns him most, which is the prospect of liberals and environmentalists dominating policy, and of a government spinning out of control, a government that in Pete’s view seizes power, limits freedoms, increases taxes, regulates markets, and diminishes prosperity.

We do not yet have national agreement on climate change. Despite the strong scientific consensus, climate change policy is contentious politically.

One option is to do nothing. Uncle Pete may well favor that option, because it appears to fit well with his sincere conviction that “if you let people keep more of their money, they will invest it in the future.” On the option of doing nothing, I may be able to help Uncle Pete think a bit more clearly. I do not claim to be an expert on energy policy or taxes, but as a climate scientist, I can say something with very high confidence about what will happen if we do nothing. Deciding to do nothing about climate change is like deciding not to have serious elective surgery, such as declining a coronary artery bypass operation that your cardiologist recommends. The operation will involve risks and costs. But declining it will also involve risks and costs, including the risk of a fatal heart attack.

Sadly, most of us do not have enough conversations about climate change. The mainstream news media largely avoid the subject, and so do many politicians. Today the fact is that we—you and I and the other 7.7 billion living people (as of November 2018)—now have our hands on the thermostat that controls the climate of our children and grandchildren. A considerable portion of the carbon dioxide we emit will remain in the atmosphere for centuries and longer. Thus, it accumulates. There is a given allowed amount of CO₂ in the atmosphere that we must not exceed if we want to limit warming to any target we pick. Science can now provide fairly accurate estimates of that allowed amount. For the warming target of the Paris Agreement, signed by almost every country in the world in late 2015, we’re already about halfway to that allowed amount of atmospheric CO₂, and we do not have much time left to bring global emissions to nearly zero. That’s why it’s urgent to drastically reduce global CO₂ emissions and to do it quickly before we exceed the allowed amount.

It’s important to realize that once a political process such as the one at Paris in 2015 has occurred, and the world has agreed on a target of how much warming is to be allowed, science can then say approximately how much more CO₂ can be emitted to allow a reasonable probability of meeting the warming target. Given the warming target, the urgency of reducing emissions is thus based directly on the physics and chemistry of the climate system. It has nothing to do with politics or ideology, once the warming target has been agreed to.

Mother Nature, which we may use as one name for the physical climate system, reacts to the total amount of CO₂. The more carbon dioxide there is in the atmosphere, the greater the climate change will be. If we who are alive today do nothing about climate change, and if the world continues to use the atmosphere as a free dump for carbon dioxide and other waste products of an energy system based on fossil fuels, then we are effectively sentencing future generations to the consequences of a severely disrupted climate. Also, the disruption will not be brief. It will take many thousands of years for the climate to recover after we stop emitting CO₂. Thus, it’s a long sentence. This is not a partisan opinion or a political statement. It is well-supported solid science.

Figure 8.2.2 The Earth is warming, just as surely as if it were immersed in a warm bath. Reproduced from Pixabay.

Figure 8.2.2 illustrates the uncomfortable fact that the Earth is now warming, just as surely as if it were immersed in a warm bath. In fact, the Earth is surrounded by an atmosphere, which acts much like a warm bath, and the atmosphere has been altered by human activities. As a result, the atmosphere now traps significantly more heat than it did in, say, 1800, before human activities adding heat-trapping substances to the atmosphere began to increase dramatically.

Military experts take this issue very seriously, and they have repeatedly characterized climate change as a threat multiplier. In the decades and centuries ahead, doing nothing would ensure that the world will inevitably see devastating climate change, including agricultural disasters on an immense scale and coastal cities abandoned worldwide because of sea level increases of many feet. If we do nothing, then because of devastating climate change, vast numbers of people will become environmental refugees, and we will see the destabilization of governments, especially in failed and failing states. In wealthy and powerful countries, like the United States, governments coping with severe climate change would surely have to act forcefully, including using emergency powers as in wartime, to preserve order and to minimize chaos and damage. Ironically, doing nothing at all about climate change, Uncle Pete’s preferred policy, is thus likely to force governments to do exactly what Uncle Pete fears most: seize power and limit freedoms. Doing nothing, whether intentionally or by neglect, is a truly disastrous policy option.

In your civil and mutually respectful conversation with your own Uncle Pete, I hope you can help him think seriously about the prospect of such a horrible, but very preventable, future. We are at a critical crossroads. If the world decides very soon to act decisively, we still have time to reduce emissions rapidly and drastically. We still have a chance of limiting climate change to a tolerable level, a level that offers some realistic chances of successful adaptation. Our window of opportunity is still open. But it won’t stay open much longer.

In my view, and that of many other climate scientists, we must act. We can’t dither any longer. If Uncle Pete wants to avoid the government controlling his life and diminishing his freedom, as all of us do, then we all need to learn about and accept the science. We all need to take the threat of climate change seriously. We all must act wisely, and urgently, to minimize it. For me, the best reason for communicating climate change science widely and accurately is that doing so can inform people and increase the likelihood that the world will act promptly, wisely, and forcefully.