Feds: World still warm
Warmest first four months on record, U.S. says.
Earth's temperature for the Jan. 1 through April 30 period was the highest for the first four months of any year in recordkeeping dating to 1880, according to the U.S. government.
The combined land-and-sea temperatures were 1.44 degrees Fahrenheit above the 20th Century average, with a margin of error of 0.16 degrees, beating out the 1.30 of 2007.
The report was released Thursday by the newly named National Centers for Environmental Information, the erstwhile National Climate Data Center. That will take some getting used to.
As for April, the feds say it was the fourth-warmest, with a globally averaged temperature of 1.33, with a margin of error of 0.14 degrees.
We mention the margin of error, because, as we've noted, taking the world's temperature isn't as simple as sticking a thermometer under the planetary armpit.
To arrive at a figure, daily high-low average temperatures at about 2,500 stations worldwide are taken on a month-by-month basis, explained government climate specialist Deke Arndt.
As for the why of using temperature "anomalies" – the differences based on 20th century averages -- the planet's thermometers do not constitute a homogeneous set. They are located at different elevations and above different terrains.
So, rather than attempting to average temperatures in different environments, Arndt said, it is tidier to measure how readings at a given site deviate from the average readings at the same site.
And, yes, no method is perfect, he said, but the major global temperature sets have been in agreement for the most part.