The planet's long-term warming trend is seen in this chart of every year's annual temperature cycle from 1880 to the present, compared to the average temperature from 1880 to 2015. In contrast, the Arctic experienced its warmest year ever, consistent with record low sea ice found in that region for most of the year. For example, both NASA and NOAA found the 2016 annual mean temperature for the contiguous 48 United States was the second warmest on record. Weather dynamics often affect regional temperatures, so not every region on Earth experienced record average temperatures last year. Researchers estimate the direct impact of the natural El Niño warming in the tropical Pacific increased the annual global temperature anomaly for 2016 by 0.2 degrees Fahrenheit (0.12 degrees Celsius). A warming El Niño event was in effect for most of 2015 and the first third of 2016. Phenomena such as El Niño or La Niña, which warm or cool the upper tropical Pacific Ocean and cause corresponding variations in global wind and weather patterns, contribute to short-term variations in global average temperature. October, November, and December of 2016 were the second warmest of those months on record – in all three cases, behind records set in 2015. 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.
Most of the warming occurred in the past 35 years, with 16 of the 17 warmest years on record occurring since 2001. The planet’s average surface temperature has risen about 2.0 degrees Fahrenheit (1.1 degrees Celsius) since the late 19th century, a change driven largely by increased carbon dioxide and other human-made emissions into the atmosphere. “We don’t expect record years every year, but the ongoing long-term warming trend is clear.” “2016 is remarkably the third record year in a row in this series,” said GISS Director Gavin Schmidt. However, even taking this into account, NASA estimates 2016 was the warmest year with greater than 95 percent certainty. Schmunk (NASA/GSFC GISS).īecause weather station locations and measurement practices change over time, there are uncertainties in the interpretation of specific year-to-year global mean temperature differences. Credit: NASA/Goddard Space Flight Center Scientific Visualization Studio. The final frame represents global temperature anomalies averaged from 2012 through 2016 in degrees Celsius. This color-coded map displays a progression of changing global surface temperatures anomalies from 1880 through 2016.
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