The Heat Is Online

US April Snow Cover Lowest in 43 Years

NASA satellite image reveals record low snow for the United States, June 2, 2010

According to the National Oceanic and Atmospheric Administration, snow cover retreated to the lowest extent ever recorded in North America by the end of this April. Snow cover was 2.2 million square kilometers below average. With records of snow extent beginning in 1967, this is the lowest in 43 years and the largest negative anomaly in the past 521 months.

A new image released by NASA shows just how little snow cover remained in April. Almost the entirety of Eastern and Midwestern United States is free of snow, while big chunks of Canada also lacked any snow cover.

While scientists stress that a single weather event cannot be linked with certainty to global climate change, trends such as earlier springs (i.e. less snow cover during spring months) are not only expected under climate change, but have been recorded in many parts of the world.

In addition to little snow cover in North America, April 2010 was the warmest April worldwide since record-keeping began in the late 19th Century: 0.76 degrees Celsius (1.37 degrees Fahrenheit) above the 20th Century average.

Record Low April Snow, June 2, 2010
Winter 2009-2010 was  much colder than normal for the United States, and it delivered a string of record-breaking snowstorms that began on the winter solstice.
 The snow and cold didn’t linger far into the spring, however. By the end of April, North American snow cover had retreated to the lowest extent in the 1967–2010 record, according to the National Oceanic and Atmospheric Administration’s April 2010 State of the Climate Report. This map shows percent snow cover across North America in April 2010 based on observations from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s  Terra satellite. Percent snow cover ranges from just above zero (light blue) to 100 percent (white). Land areas with no detectable snow cover during the month are gray.
According to NOAA, “Across North America, snow cover for April 2010 was 2.2 million square kilometers below average — the lowest April snow cover extent since satellite records began in 1967 and the largest negative anomaly to occur in the 521 months that satellite measurements are available.” Unusual warmth descended on North America in April, leading to both low snowfall amounts and rapid melt of existing snow.