By Brandon Miller, CNN
updated 10:12 AM EDT, Fri September 27, 2013
(CNN) — Human activity has caused at least half of climate change in the last half-century, hundreds of scientists say. They are 95% certain of this, the surest they’ve ever been, says a United Nations report published Friday.
That activity? Driving cars, running power plants on coal and oil, torching swathes of forestland and debris; anything involving burning carbon-based fuels and emitting greenhouse gases.
We are seeing the consequences already in extreme weather patterns, particularly drought and flood, and they will probably get worse this century, the report said.
“It should serve as yet another wake-up call our activities today have a profound impact on society, not only for us, but for many generations to come,” Michel Jarraud, head of the World Meteorological Organization, said at a news conference in Stockholm, Sweden.
U.S. Secretary of State John Kerry echoed his words in an official statement.
“Those who deny the science or choose excuses over action are playing with fire,” he said. “Once again, the science grows clearer, the case grows more compelling, and the costs of inaction grow beyond anything that anyone with conscience or common sense should be willing to even contemplate.”
Beneath Greenland’s ice, a grand canyon
The assessment report from the Intergovernmental Panel on Climate Change is the benchmark study on global warming published every few years. Nearly 1,000 researchers from around the world work on the document, which then undergoes review by about as many scientists.
The panel released a summary report Friday and plans to post the full version, roughly 2,500 pages, online on Monday.
Global Climate Change