Much of the delay in climate adaptation planning is because of the uncertainty surrounding actual impacts to our communities and the severity of these impacts. This uncertainty is trumpeted by our new EPA Administrator Scott Pruitt and by the House Science Committee Chairman Lamar Smith as reason to not take action. They argue the models do not all agree and the models suggest there is still much uncertainty as to the role humans have on our changing climate. However, like the planet’s polar bears, the iceberg they are standing on is becoming smaller each day.
Climate scientists for years have been able to say with certainty that human activities are directly influencing the climate. This all started about 200 years ago with French Mathematician Joseph Fourier and scientists’ continued to develop their understanding of the role of human activities on greenhouse gas concentrations in our atmosphere to present day. You can see the entire timeline of greenhouse gas discovery at Dr. Katharine Hayhoe’s Global Weirding series.
In March of this year, the climate scientist scored another victory for certainty with a new study conducted by Mann et al, published in Nature Scientific Reports. This report provides an even stronger link between man-made global warming and extreme weather events. Through both observation of real data and the use of the CMIP5 historical climate model, brought to you by the nation’s Lawrence Livermore National Lab, they were able to show that the air streams that circle our planet are not acting as expected and this funny behavior can be attributed to a rapidly warming arctic. By the air streams not shifting, or undulating, as they have historically, but rather staying stuck in place, persistent weather patterns occur that result in extreme weather events. Check out the article by John Abraham at The Guardian to get a great breakdown of the study.