President Obama spoke to students in Mexico City this morning about a variety of subjects, but I was especially glad to hear this line: "Climate change is happening. The science is undeniable."
The ratio of carbon dioxide in Earth's atmosphere is flirting with 400 parts per million, a level last seen about 2.5 million to 5 million years ago, according to the Scripps Institution of Oceanography at the University of California, San Diego. [...]Isolated measurements have peaked at above 400 parts per million in the Arctic, but scientists are more alarmed at steady readings from Mauna Loa, Hawaii, far from major pollution sources. Those measurements, considered to be the most reliable indicators of Earth's atmospheric content, could breach the 400 level this month, according to Scripps. [...]For the previous 800,000 years, CO2 levels never exceeded 300 parts per million, and there is no known geologic period in which rates of increase have been so sharp. The level was about 280 parts per million at the advent of the Industrial Revolution in the 18th century, when the burning of fossil fuels began to soar.
You've probably heard of 350.org, a group/movement founded Bill McKibben, which works on combating the climate crisis. The name of the organization has a specific meaning -- it refers to the goal of 350 parts per million for carbon emissions, a level scientists tell us is necessary to avoid climate catastrophes.
We're now "flirting with 400 parts per million," and moving in the wrong direction.
Making matters slightly worse, the United States will struggle to play a leadership role in addressing the crisis because many in Congress are convinced the totality of climate science is a communist conspiracy and a hoax perpetrated by greedy scientists who hate the American way of life.