Nearly 24 years ago, NASA researcher James Hansen said:   The greenhouse effect had been detected.  And it is changing our climate now .  It was at that time the hottest 12-month period scientists had ever seen. Returning to the present, 2021 was only the fifth or sixth hottest year, even though July was the hottest month humanity has recorded.   Further, the seven hottest years on record have happened in the last seven years. Further : Since 1981, average global temperatures have increased at a rate of about 0.18 degrees Celsius (0.32 degrees Fahrenheit) per decade. In the same period, the warming of oceans — which have absorbed about 90 percent of the additional heat trapped by human carbon pollution — has gotten eight times faster. Finally : The United States endured at least   20 weather disasters costing $1 billion or more   last year, the second most on record, NOAA announced this week. Hurricanes, wildfires, tornadoes and floods — almost all of them made worse by climate change