Air temperature in 2018 at a height of two meters, compared to 1981–2010 average. Data from the Copernicus Climate Change Service shows that 2018 was the fourth in a series of exceptionally warm years, with atmospheric CO2 concentrations continuing to rise. Source: Copernicus Climate Change Service, ECMWF

How we know the Earth is warming and humans are responsible

By Dana Nuccitelli, May 1, 2020

https://thebulletin.org/wp-content/uploads/2019/06/Temp_differences-150x150.jpg

Air temperature in 2018 at a height of two meters, compared to 1981–2010 average. Data from the Copernicus Climate Change Service shows that 2018 was the fourth in a series of exceptionally warm years, with atmospheric CO2 concentrations continuing to rise. Source: Copernicus Climate Change Service, ECMWF

The American public is poorly informed about the existence and primary cause of global warming. Just 67 percent of Americans are confident in the knowledge that global warming is happening, and a mere 53 percent understand that it’s mostly caused by human activities, while 33 percent of Americans continue to believe that global warming is mostly natural (Marlon et al. 2019). Of the latter, 13 percent believe that humans are not at all responsible for climate change, and a further 5 percent say the climate is not changing; this level of misconception is worse in the United States than any other developed country (Milman and Harvey 2019).

RELATED:
RELATED: Despite pledges to take action, almost no nations are cutting down fossil fuel production

The situation is dramatically different among those who make a career of studying climate change; numerous studies using a variety of survey methods have found that there is a 90-to-100 percent expert consensus on human-caused global warming (Cook et al. 2016). This raises an oft-heard question, which can be loosely phrased as: How do the experts know that global warming is happening, and that humans are the cause? Herein is a summary of the evidence underlying what has been described as a “knowledge-based consensus” (Jacobs et al. 2018).

As the coronavirus crisis shows, we need science now more than ever.

The Bulletin elevates expert voices above the noise. But as an independent, nonprofit media organization, our operations depend on the support of readers like you. Help us continue to deliver quality journalism that holds leaders accountable. Your support of our work at any level is important. In return, we promise our coverage will be understandable, influential, vigilant, solution-oriented, and fair-minded. Together we can make a difference.


Get alerts about this thread
Notify of
guest
0 Comments
Inline Feedbacks
View all comments