Last year was the hottest since scientists started keeping track of global temperature data in the late 1880s, .
It may not have felt that way for much of the United States, as the East Coast and Midwest experienced cooler-than-average temperatures, but virtually the entire rest of the world experienced above-average temperatures. Global temperatures were up 0.7 degrees Fahrenheit.
2014 marked the 38th consecutive year of above-average temperatures. The 10 hottest years on record have come since 1997, and most scientists credit human emissions with causing the relentless rise in temperatures.
Scientists were puzzled that the record-setting year came in a year without El Ni帽o, a periodic weather event that releases heat from the oceans into the atmosphere and characterized many recent hottest years. Some have speculated that the next El Ni帽o year will easily exceed global temperature records.