In March of 2011, planetwide temperature readings kept their recent tendency toward unusual warmth. Last week NASA’s Goddard Institute for Space Studies released its latest data on average global temperature — a dataset stretching back in time to January 1880 and forward through last month. Based on direct readings of temperature around the planet over land and sea, NASA ranks March 2011 as the 9th hottest March on record.
Considered in isolation, that’s just one measure in time, but placed in the context of other measurements in the dataset it’s clear that March 2011 is a continuation of a long period of change in the climate. The globe is warming. Check the data for yourself and you’ll see there hasn’t been a single month in which the Earth was cooler than the 1951-1980 average temperature for 17 years; that kind of streak is supremely unlikely to have occurred by chance alone.
Well, maybe, you might be thinking to yourself, maybe some of the other really hot Marches have happened far back in the past, in the late 1800s or the early 1900s. That’s a fair question; let’s check back in time to see the actual trend over the years:
The following are the 10 hottest Novembers over land and sea around the globe in the Goddard Institute data:
Hottest on record: 2002
2nd hottest on record: 2010
3rd hottest on record: 2005
4th hottest on record: 2008
5th hottest on record: 2007
6th hottest on record: 1990
7th hottest on record: 2006
8th hottest on record: 2004
9th hottest on record: 2011
10th hottest on record: 1998
And the following are the ten coldest Novembers on record in the Goddard Institute’s global data:
Coldest on record: 1911
2nd coldest on record: 1898
3rd coldest on record: 1917
4th coldest on record: 1888
5th coldest on record: 1908
6th coldest on record: 1909
7th coldest on record: 1913
8th coldest on record: 1884
9th coldest on record: 1887
10th coldest on record: 1890
That’s not a random distribution of temperature. The coldest years are the earliest, the hottest years are the latest. That’s climate change. That’s global warming.
