In the US, we celebrate Thanksgiving this week, which for many of us means dining with family and friends we have not seen in a while. Given the current tumultuous political climate, some people are likely to be passing more than just the potatoes. A source of major concern with the incoming administration is their lack of commitment toward addressing the very real threat to the future of our planet posed by climate change.
So how do you talk to someone who is skeptical about the impact climate change will have? Or maybe that skeptic is you—there is so much information and rumor out there. How do we know what to trust? Well, I’ve got you covered! Let’s break down some of the biggest sources of conflicting information and common misconceptions surrounding climate science.
Misconception #1: Scientists do not agree that climate change is real.
There are many unanswered questions that serve as the source of heated debates among scientists—what is dark matter? Are we alone in the universe? How can we overcome bacterial resistance? Can we cure cancer? What is at the bottom of the ocean? just to name a few —but the reality of global warming is not one of them. A whopping 97% of actively publishing climate scientists agree that the planet is warming and that human activity is likely the cause. Over 200 scientific organizations worldwide have issued statements supporting this position, including the American Physical Society, the US National Academy of Sciences, and the Intergovernmental Panel on Climate Change. Even the U.S. Navy agrees.
Consensus is so high, in fact, that in late 2015 representatives from 195 countries negotiated the Paris Agreement at the 21st Conference of the Parties of the United Nations Framework Convention on Climate Change. Signatories offer their commitment to mitigating greenhouse gas emissions, with an emphasis on financial incentives that promote activities and development that do not increase these emissions, as well as a commitment to investing in our ability to adapt to the adverse impacts of climate change so as to not threaten food production. To date, the agreement has been ratified by 109 countries.
In a meeting of over 200 nations last week in Marrakech, Morocco, countries including the US and China confirmed their participation in the effort to reduce greenhouse gas emissions and reliance on fossil fuels. Unfortunately, members of the incoming administration in the US have voiced plans to abandon the agreement. Such a move would not only hinder the global effort to reduce the impact of global warming—the US produces ~16% of the world’s greenhouse gases—but would also very likely strain diplomatic ties with the large number of participating countries.
Among the general US population, concern about global warming is currently the highest it has been in 8 years. In a recent Gallup poll, 64% of respondents were concerned a “great deal or a fair amount” about global warming with 59% believing that the effects of global warming had already begun. Only 10% of those polled believed we will never see any adverse effects from rising temperatures. Thus, the only people who appear to dispute the claim that the Earth is warming in any significant numbers are politicians.
So 97% of climate scientists have determined global warming to be a real concern. Of course, not all of us are climate scientists and thus able to analyze the data ourselves. Let’s say 97% of all of the actively practicing doctors in the US told me that I needed surgery. But what if the prospect of that surgery made me nervous and would require a big adjustment of how I was used to living? Would I keep looking until I found one doctor, or even a group of politicians, who disagreed? No. You’d better believe I’d get that surgery.
Misconception #2: Climate scientists are exaggerating the issue.
Climate scientists have very little to gain from lying about or exaggerating their results. A major evaluator of success in a scientific career is the quantity and quality of publications the scientist has produced. Publishing scientific results requires in most cases critical reviews from your peers and competitors making it very difficult to fake results.
Monetary gains for climate scientists are also not evident. The biggest winners—if anyone can be called a winner—from increased attention to anthropogenic rises in global temperatures will be companies focused on renewable energy sources. However, there is still relatively little investment in such companies—half of the top 10 global companies are in fossil fuels according to Fortune – and renewable energy companies don’t typically employ climate scientists.
Perhaps some of this doubt arises because the study of climate science involves complicated models of sources and sinks of greenhouse gases and multiple other competing factors. Any reasonable model will require a number of tunable parameters meaning that the resulting conclusions cannot be 100% certain. But 100% certainty is rare in science. For example, in medicine, we don’t consider it unusual to ask, “what are the chances of this treatment curing my illness?”
Rarely does anything in life require 100% certainty for us to take action. If it did, we’d be in real trouble because no one would ever choose to become parents. We are comfortable assessing risk and deciding on actions to take without demanding 100% certainty and our reaction to climate models should not be any different.
There are thousands rigorous scientific studies that indicate global temperatures have steeply increased due to human activity. 2015 was the hottest year on record and 2016 will likely beat it. Globally, sea ice is melting. Levels of carbon dioxide in the atmosphere have spiked. Even given the uncertainties inherent in any complicated climate model, the odds are not in our favor.
Misconception #3: Global warming can't be a serious issue because it's still really cold too.
Many of us have heard the argument, including from our own president-elect, that global warming can’t possibly be real because in my neck of the woods, it is currently freezing/snowing/cold. Last year a senator from Oklahoma brought a snowball to the Senate floor as supposed “proof” that global warming cannot be a real problem. Can the Earth be warming if some places are still experiencing very cold winters?
The answer, of course, is yes. The global warming predictions from scientists suggest that on average across the globe, temperatures are rising, and this is undeniably the case. However, this is an average. While parts of the US are experiencing cold temperatures, people are cooking eggs on the sidewalk thanks to heat waves in Australia. Even given the winter storms in the US, many day-to-day heat records were still set in 2014 and 2015 in other US locations.
Extreme weather of any kind is also a predicted outcome from climate models along with global warming. More heat and thus moisture in the air can affect not just heat waves and droughts but also storms, even winter ones.
Misconception #4: Humans aren’t causing global warming so there is nothing we can do.
Even among those who do not deny the clear trends that the Earth is warming, some dispute the cause. Volcanoes, for example, produce carbon dioxide emissions although at an estimated rate more than 130 times less than human activity, according to the US Geological Survey. When combined, natural sources do indeed dominate the production of greenhouse gases in the atmosphere. However, over the Earth’s 4.5 billion year history, natural sources and sinks of greenhouse gases like forests and oceans have settled into a balance that has kept the level of carbon dioxide in the atmosphere relatively stable for thousands of years. We know this to be true because scientists can measure historic levels of CO2 directly from tree rings and ice cores in the Antarctic.
That stability has begun to falter since the Industrial Revolution. In other words, even though the human contribution to greenhouse gas emissions through fossil-fuel burning and deforestation is a small fraction compared to the entirety of nature’s additions, nature provides appropriate mechanisms for absorbing and thus balancing its emissions. Humans do not. The result has been a dramatic 35% rise in CO2 levels since 1832.
Some skeptics point out that since carbon dioxide makes up only an extremely small percentage of the Earth’s atmosphere, curbing those emissions won’t really make a dent. Others further suggest that water vapor may be a bigger culprit so the focus on carbon dioxide is again misplaced.
Water vapor has been proven to be a major contributor to global warming, but its main role is in amplifying the effects of increasing levels of carbon dioxide. While the amount of CO2 in the atmosphere can drive temperatures to rise and rise and rise because CO2 serves as an effective heat trap, the amount of water vapor the Earth’s atmosphere can hold is ultimately limited by the ambient temperature. Thus, while in a given location in the atmosphere, water vapor may directly raise the temperature more than the CO2 that is present, water vapor cannot drive a continued rise in temperatures the same way that CO2 can.
Astronomical sources, like variations in the sun’s output or cosmic rays, are also logical places to look for an explanation for the observed increase in global temperatures. After all, solar variations are predicted to have been a main reason for the planet’s ice ages. Thus, climate scientists do take these sources into account in their atmospheric models, but so far, convincing evidence has not been found to suggest that solar-related phenomena outweigh human contributions.
Even if the models underestimate the contribution from variations in the solar cycle, the fact remains that human CO2 production works to amplify the existing ambient temperature. Thus, any contribution from human activity in a time of peak solar warming would warrant our attention.
Even if we want to dispute the predicted impact or even causes of global warming, a more important question may be whether or not any differences in opinion change how we decide to react. As a country we spend trillions of dollars in military spending to guard against potential threats. Is it not reasonable to spend a fraction of that cost to protect against the possible threat of rising global temperatures?
If your holiday discussion does turn to climate science, remember to start from a place of common ground. Do you both have a favorite sea shore spot that could be lost to rising sea levels? What about a favorite food that may be subject to shortages should the worst of climate predictions prove true? Investing in climate change requires sacrifices in the short term for long term gains which can be a hard sell so we need everyone we can get on board.
For more detailed explanations of some of the topics discussed in this episode, you can check out the frequently asked questions guide written by the Intergovernmental Panel on Climate Change.
Until next time, this is Sabrina Stierwalt with Everyday Einstein’s Quick and Dirty Tips for helping you make sense of science. You can become a fan of Everyday Einstein on Facebook or follow me on Twitter, where I’m @QDTeinstein. If you have a question that you’d like to see on a future episode, send me an email at everydayeinstein@quickanddirtytips.com.
Earth image courtesy of shutterstock. Rising CO2 plot courtesy of nasa.gov
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