NOAA's NCDC's State of the Climate, Global Analysis for March 2010: Hottest March ever recorded

State of the Climate 

Global Analysis, March 2010

NOAA's National Climatic Data Center

 Global Highlights

• The combined global land and ocean average surface temperature for March 2010 was the warmest on record at 13.5 °C (56.3 °F), which is 0.77 °C (1.39 °F) above the 20^th century average of 12.7 °C (54.9 °F). This was also the 34^th consecutive March with global land and ocean temperatures above the 20^th century average.
• The March worldwide land surface temperature was 1.36 °C (2.45 °F) above the 20^th century average of 5.0 °C (40.8 °F)—the fourth warmest on record.
• The worldwide ocean surface temperature was 0.56 °C (1.01 °F) above the 20^th century average of 15.9 °C (60.7 °F) and the warmest March on record.
• For the year-to-date, the global combined land and ocean surface temperature of 13.0 °C (55.3 °F) was the fourth warmest January-March period. This value is 0.66 °C (1.19 °F) above the 20^th century average.

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Please Note: The data presented in this report are preliminary. Ranks and anomalies may change as more complete data are received and processed. Effective with the July 2009 State of the Climate Report, NCDC transitioned to the new version (version 3b) of the extended reconstructed sea surface temperature (ERSST) dataset. ERSST.v3b is an improved extended SST reconstruction over version 2. For more information about the differences between ERSST.v3b and ERSST.v2 and to access the most current data, please visit NCDC's Global Surface Temperature Anomalies page.

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Introduction

Temperature anomalies for March 2010 are shown on the dot maps below. The dot map on the left provides a spatial representation of anomalies calculated from the Global Historical Climatology Network (GHCN) dataset of land surface stations using a 1961-1990 base period. The dot map on the right is a product of a merged land surface and sea surface temperature (SST) anomaly analysis developed by Smith et al. (2008). For the merged land surface and SST analysis, temperature anomalies with respect to the 1971-2000 average for land and ocean are analyzed separately and then merged to form the global analysis. For more information, please visit NCDC's Global Surface Temperature Anomalies page.

March Land Surface Temperature
Anomalies in degrees Celsius

March Blended Land and Sea Surface
Temperature Anomalies in degrees Celsius

March 2010

The combined global land and ocean surface temperature anomaly for March 2010 was 0.77 °C (1.39 °F) above the 20^th century average, resulting in the warmest March since records began in 1880. The previous record was set in 2002 when temperatures were 0.74 °C (1.33 °F) above the 20^th century average. Sea surface temperatures (SST) during March 2010 were warmer than average across much of the world's oceans, with the cooler-than-average conditions across the higher-latitude southern oceans, across parts of the northern Pacific Ocean, and along the western coast of South America. Warmer-than-average conditions were most pronounced in the equatorial portions of the oceans, where the tropical ocean surface temperature (equatorward of 20° latitude) also had its warmest March on record. The March 2010 worldwide SST ranked as the warmest on record, with an anomaly of 0.56 °C (1.01 °F) above the 20^th century average—the previous record was set in 1998. El Niño weakened to moderate strength during March; however, it contributed significantly to the warmth observed in the tropical belt and the overall ocean temperature. According to NOAA's Climate Prediction Center, El Niño is expected to continue through the Northern Hemisphere spring 2010 and transition to ENSO-neutral conditions by the Northern Hemisphere summer 2010.

Did you know?

In climate change studies, temperature anomalies are more important than absolute temperature. A temperature anomaly is the difference from an average, or baseline, temperature. The baseline temperature is typically computed by averaging 30 or more years of temperature data. A positive anomaly indicates the observed temperature was warmer than the baseline, while a negative anomaly indicates the observed temperature was cooler than the baseline. When calculating an average of absolute temperatures, things like station location or elevation will have an effect on the data (ex. higher elevations tend to be cooler than lower elevations and urban areas tend to be warmer than rural areas). However, when looking at anomalies, those factors are less critical. For example, a summer month over an area may be cooler than average, both at a mountain top and in a nearby valley, but the absolute temperatures will be quite different at the two locations.

Using anomalies also helps minimize problems when stations are added, removed, or missing from the monitoring network. The above diagram shows absolute temperatures (lines) for five neighboring stations, with the 2008 anomalies as symbols. Notice how all of the anomalies fit into a tiny range when compared to the absolute temperatures. Even if one station were removed from the record, the average anomaly would not change significantly, but the overall average temperature could change significantly depending on which station dropped out of the record. For example, if the coolest station (Mt. Mitchell) were removed from the record, the average absolute temperature would become significantly warmer. However, because its anomaly is similar to the neighboring stations, the average anomaly would change much less.

The worldwide land surface temperature was the fourth warmest on record, with a temperature anomaly of 1.36 °C (2.45 °F) above the 20^th century average. During March 2010, warmer-than-average conditions dominated the globe, with the most prominent warmth in northern Africa, the Middle East, South Asia and Canada. Cooler-than-average conditions were present across Mongolia, central and eastern Russia, northern and western Europe, Mexico, the southeastern U.S., northern Australia, and western Alaska.

Most of Canada was engulfed by abnormally warm conditions during March 2010. Mean temperature records were set or tied across Ontario, Canada, as mean temperatures were 2.5-8.1 °C above the March average, according to Environment Canada.

The March 2010 average temperature across China was 3.4 °C (38.1 °F), which is 0.02 °C (0.04 °F) above the 1971-2000 average of 3.2 °C (37.8 °C)—according to Beijing Climate Center (BCC). It was reported that Tibet experienced its second warmest March temperatures since historic records began in 1951 (Source: BCC).

According to the India Meteorological Department (IMD), many locations across India experienced their warmest March maximum, minimum, or mean temperatures on record. Delhi, India experienced above-average temperatures during March 2010. The average maximum and minimum temperatures for March 2010 were 34.1 °C (93.4 °F) and 18.6 °C (65.5 °F)—which is 4.1 °C (7.4 °F) and 3.2 °C (5.8 °F) above average, respectively. These were the second warmest March maximum and minimum temperatures, behind 1953 (34.3 °C [93.7 °F]) and 1916 (18.8 °C [65.8 °F]), respectively. Delhi's average mean temperature during March 2010 was 26.3 °C (79.3 °F), the second warmest March mean temperature on record, behind 1953 (26.4 °C [79.5 °F]). Records in Delhi began in 1901. Please see IMD's March 2010 report for additional information.

The March 2010 average temperature for the Northern Hemisphere as a whole (land and ocean surface combined) was 0.92 °C (1.66 °F) above the 20^th century average—the third warmest March on record, behind 2008 (warmest March) and 1990 (second warmest March). The Northern Hemisphere ocean temperature during March 2010 ranked as the warmest March on record, with an anomaly of 0.54 °C (0.97 °F) above the 20^th century average. The previous record was set in 2004 when the Northern Hemisphere March ocean temperature was 0.49 °C (0.88 °F) above the 20^th century average. The March 2010 Northern Hemisphere land temperature was the fourth warmest on record (1.52 °C [2.74 °F] above the 20^th

century average).

The average temperature for the Southern Hemisphere as a whole (land and ocean surface combined) was 0.64 °C (1.15 °F) above the 20^th century average—the second warmest March on record, behind 1998. The Southern Hemisphere ocean temperature during March 2010 also represented the second warmest, with an anomaly of 0.59 °C (1.06 °F) above the 20^th century average. The March 2010 Southern Hemisphere land temperature was 0.95 °C (1.71 °F) above the 20^th century average—the warmest on record. The previous record was set in 1998.

Year-to-date (January-March)

The January-March 2010 map of temperature anomalies shows that for the first three months of the year anomalous warm temperatures were present over much of the world, with the exception of cooler-than-average conditions across the higher-latitude southern oceans, the northern Pacific Ocean, and along the western South American coast, Mongolia, northern China, northern Australia, the south central and southeastern contiguous U.S., northern Mexico, and most of Europe and Russia. The combined global land and ocean surface temperature for January-March period was the fourth warmest on record. This value is 0.66 °C (1.19 °F) above the 20^th century average. Separately, the worldwide land surface temperature ranked as the fifth warmest on record, while the worldwide ocean surface temperature ranked as the second warmest January-March on record—behind 1998.

Link:  http://www.ncdc.noaa.gov/sotc/?report=global