As the lone scientist in many aspects of my life, I feel like I am obligated to make a statement on climate change for my friends and family. The purpose of this is not to dive into politics, but to provide you with my own perspective as a scientist on the issue. Additionally, I would like to offer an analogy that can easily be used in conversation.
I am a member of the American Physical Society (does that make you jealous?) and the society has an official position that “[t]he evidence is incontrovertible: Global warming is occurring” as a result of “human activities.”1 And after I used a dictionary to understand what “incontrovertible” meant, over 51,000 physicists stand by the statement that global warming is real and caused by us. There are many other science organizations that have similar positions (American Chemical Society, American Association for the Advancement in Science, American Meteorological Society, etc.).
Climate change skeptics most often use the scientific result from the 1990s that measured the temperature of Earth’s troposphere with satellites.2 Remember that guy from Red Bull that jumped out of a hot air balloon basically from space? Well, the last 10 miles he fell before reaching Earth was the troposphere. In this paper, they found that while the surface temperature of the Earth was increasing, the temperature of the troposphere was actually getting colder. Not surprisingly, people who disagree with climate change point to this paper as evidence. In fact, the U.S. Representative serving as the chairman for the Committee on Science, Space and Technology (though he is not a scientist) recently alluded to this paper.
Although that paper was a good first attempt, researchers in the early 2000s found a flaw.3 The new calculations, when done correctly, showed a continual increase in temperature matching the expected change from global warming. This is typically how science works; research grows on other research, and the new results either verify the old ones, or the old ones are no longer valid.
True academic consensus can only be determined when scientific contributions are taken as a whole. Focusing on one (blemished) result is taking science out of context. An analogy to this is as follows: you are a casual tennis player and you lose 0-6, 0-6, 0-6. If this is the only information I have, it would be reasonable for me to conclude that you are a horrible tennis player. But if I learn that this score is from a match you played with Novak Djokovic, I can’t necessarily conclude that anymore. I can’t choose to focus on only the score when I have additional information to consider.
The same goes for science; I can’t focus on one result, I need to take all results into account before I make a conclusion. Unfortunately, this is difficult because we aren’t all scientists, so we are liable to being exposed to scientific results taken out of context. But when almost every scientist agrees that global warming exists and is a result of human actions, it seems unreasonable to point out extraneous contributions and give them equal weight in an argument against the whole scientific body.
I hope this is enlightening, thought provoking, and not enough to get me assassinated,
2) Christy, Spencer, and McNider, J. Climate, 8, 888–896 (1995)
3) Mears and Wentz, Science, 309, 1548-1551 (2005)
A PDF of this statement is available here: Climate Statement