The Science of Climate Change


The current warming trend is important because most of it is extremely likely (greater than 95 percent probability) to be the result of human activity since the mid-20th century and continues at a rate that is unprecedented over decades to millennia.
The Earth’s average surface temperature has risen about 1.62 degrees Fahrenheit (0.9 degrees Celsius) since the late 19th century. This is caused largely by increased carbon dioxide & other human-made emissions into the atmosphere. Most of the warming occurred in the past 35 years, with the five warmest years on record taking place since 2010. Not only was 2016 the warmest year on record, but eight of the 12 months that make up the year — from January through September, with the exception of June — were the warmest on record for those respective months.
The oceans have absorbed much of this increased heat, with the top 700 meters (about 2,300 feet) of ocean showing warming of more than 0.4 degrees Fahrenheit since 1969.
Global sea level has risen about 8 inches in the last century. The rate in the last two decades, however, is nearly double that of the last century and is accelerating slightly every year.

SOURCE: NASA