Scientists at Berkeley Earth say our planet experienced the fourth warmest year on record. Last year’s average temperature was 58.9 degrees Fahrenheit – 1.4 degrees warmer than the average from 1951 to 1980 and about 2 degrees warmer than pre-industrial times.  Pennsylvania State University climate scientist Michael Mann, who wasn’t part of the Berkeley Earth team, said the fact that nearly every year recently is in the top five or top 10 hottest years is clear evidence of human-caused warming on this planet.