Planet Sees Second Warmest May on Record

Global weather events for May 2012. CREDIT: NOAA View full size image

Last month, the global average temperature climbed to the second highest for May on record since 1880, according to U.S. National Oceanographic and Atmospheric Administration (NOAA) records. 

Much of the world, including nearly all of Europe, Asia, northern Africa, most of North America and southern Greenland experienced above average May temperatures. In fact, last month wrapped up the warmest spring on record for the continental U.S., NOAA records show.

The global May record included the combined global land and ocean average surface temperatures for the month, which 1.19 degrees Fahrenheit (0.66 degrees Celsius) above the 20th-century average of 58.5 F (14.8 C). This record was beat only in 2010, when the global average was 1.24 F (0.69 C) above the 20th-century average.

The Northern Hemisphere saw its warmest May on record — 1.53 F, or 0.85 C above average — while the Southern Hemisphere's May ranked ninth warmest among all Mays on record, at 0.85 F (0.47 C) above average.

Of course, it wasn't unusually warm everywhere. Australia, Alaska and parts of the western U.S.-Canadian border were notably cooler than average. 

Snow cover on the Northern Hemisphere was significantly below average in May, according to NOAA records. 

Globally, this spring ranked as the fourth warmest. Meanwhile, May brought a slew of temperature records to the continental U.S. after an unusually warm spring and mild winter. [10 Weird Weather Events]

Because of natural fluctuations in weather, climate scientists are loath to connect events that occur over a short-time frame, from a strong storm to an unusual warm spring, to climate change. However, the warming effect of humans' greenhouse gas emissions forms a backdrop for the weather the world is experiencing and shows up as a longer-term trend. It is not a coincidence that the first decade of this century was the warmest on record, according to NOAA's State of Climate in 2010 report.

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