BISC 3 Lecture 11: Chapter 9.2 Climate Change
Document Summary
The conclusion is a 90% certainty that observed climate change is caused by human activity: subsequent reports raised that certainty to 99%. Changes in heat waves, sea level, and storms are expected: the 4th ipcc report presents a variety of climate scenarios for predicted emissions of greenhouse gases. Evidence: nearly all mountain glaciers are retreating rapidly and many have disappeared entirely, satellite images and surface measurements show that growing seasons are now as much as three weeks longer in a band across northern eurasia and. North america than they were 30 years ago: droughts are becoming more frequent and widespread, plants and animals are breeding earlier or extending their range into new territory, coral reefs worldwide are bleaching, losing key algae. In kyoto, japan, in 1997, 160 nations agreed to roll back co2, methane, and nitrous oxide emissions about 5 percent below 1990 levels by 2012, but china and.
