Global Analysis - February 2012
Note: GHCN-M Data Notice
An omission in processing a correction algorithm led to some small errors on the Global Historical Climatology Network-Monthly dataset (GHCN-M v3.2.0). This led to small errors in the reported land surface temperatures in the October, November, December and Annual U.S. and global climate reports. On February 14, 2013, NCDC fixed this error in its software, included an additional improvement (described below), and implemented both changes as GHCN-M version 3.2.1. With this update to GHCN-M, the Merged Land and Ocean Surface Temperature dataset also is subsequently revised as MLOST version 3.5.3.
The net result of this new version of GHCN-M reveals very small changes in temperature and ranks. The 2012 U.S. temperature is 0.01°F higher than reported in early January, but still remains approximately 1.0°F warmer than the next warmest year, and approximately 3.25°F warmer than the 20th century average. The U.S. annual time series from version 3.2.1 is almost identical to the series from version 3.2.0 and that the 1895-2012 annual temperature trend remains 0.13°F/decade. The trend for certain calendar months changed more than others (discussed below). For the globe, ranks of individual years changed in some instances by a few positions, but global land temperature trends changed no more than 0.01°C/century for any month since 1880.
NCDC uses two correction processes to remove inhomogeneities associated with factors unrelated to climate such as changes in observer practices, instrumentation, and changes in station location and environment that have occurred through time. The first correction for time of observation changes in the United States was inadvertently disabled during late 2012. That algorithm provides for a physically based correction for observing time changes based on station history information. NCDC also routinely runs a .pairwise correction. algorithm that addresses such issues, but in an indirect manner. It successfully corrected for many of the time of observation issues, which minimized the effect of this processing omission.
The version 3.2.1 release also includes the use of updated data to improve quality control and correction processes of other U.S. stations and neighboring stations in Canada and Mexico.
Compared to analyses released in January 2013, the trend for certain calendar months has changed more than others. This effect is related to the seasonal nature of the reintroduced time-of-observation correction. Trends in U.S. winter temperature are higher while trends in summer temperatures are lower. For the globe, ranks of individual years changed in some instances by a few positions, but global temperature trends changed no more than 0.01°C/century for any month since 1880.
More complete information about this issue is available at this supplemental page.
NCDC will not update the static reports from October through December 2012 and the 2012 U.S and Global annual reports, but will use the current dataset (GHCN-M v. 3.2.1 and MLOST v. 3.5.3) for the January 2013 report and other comparisons to previous months and years.
Contents of this Section:
- The combined average temperature over global land and ocean surfaces for February 2012 was the 22nd warmest on record and the coolest since 2008, at 12.47°C (54.57°F), which is 0.37°C (0.67°F) above the 20th century average of 12.1°C (53.9°F).
- Looking only at land, the global land surface temperature was 0.38°C (0.68°F) above the 20th century average of 3.2°C (37.8°F), making this the 37th warmest February on record and the coolest February since 1994. It was also the coolest month on record since January 2008. Warmer-than-average conditions occurred across nearly all of Canada and Alaska, the eastern half of the United States, southern Greenland, and north central Russia. Cooler-than-average regions included northeastern Africa, most of Europe and central Asia, and much of Australia.
- Separately, the global land surface temperature was 0.38°C (0.68°F) above the 20th century average of 3.2°C (37.8°F), making this the 37th warmest February on record and the coolest February since 1994. It was also the coolest month on record since January 2008.
- For the ocean, the February global sea surface temperature was 0.36°C (0.65°F) above the 20th century average of 15.9°C (60.6°F), making it the 12thth warmest February on record. The warmth was most pronounced across the north central Pacific, the North Atlantic, much of the eastern Indian Ocean, and portions of the mid-latitude Southern oceans.
- For the ocean, the February global sea surface temperature was 0.36°C (0.65°F) above the 20th century average of 15.9°C (60.6°F), making it the 12thth warmest February on record.
- The combined global land and ocean average surface temperature for the December–February period was 0.41°C (0.74°F) above the 20th century average of 12.1°C (53.8°F), making it the 17th warmest such period on record and the coolest December–February since 2008.
- The December–February worldwide land surface temperature was 0.59°C (1.06°F) above the 20th century average, the 20th warmest such period on record. The global ocean surface temperature for the same period was 0.33°C (0.59°F) above the 20th century average and was the 15th warmest such period on record.
- The combined global land and ocean average surface temperature for the January–February period was 0.37°C (0.67°F) above the 20th century average of 12.1°C (53.8°F), making it the 20th warmest such period on record.
- The January–February worldwide land surface temperature was 0.43°C (0.77°:F) above the 20th century average, the 33rd warmest such period on record. The global ocean surface temperature for the year to date was 0.34°C (0.61°F) above the 20th century average and was the 14th warmest such period on record.
- La Niña continued to weaken during February 2012. According to NOAA's Climate Prediction Center, La Niña is expected to dissipate by the end of April 2012.
- The average Arctic sea ice extent during February was 6.9 percent below average, ranking as the fifth smallest February extent since satellite records began in 1979. The five smallest February Arctic ice extents have occurred in the last seven years. February 2012 is the 14th consecutive February and the 129th consecutive month with below-average Arctic sea ice extent.
- On the opposite pole, the Antarctic sea ice extent during February was 20.3 percent above average, the fifth largest on record.
- The Northern Hemisphere snow cover extent for February was the eighth largest monthly extent on record. The North American snow cover extent was the 16th smallest, while the Eurasian snow cover was the third largest February extent on record. The Eurasian February snow cover of 12.0 million square miles (31.2 million square km) was also the fifth largest snow cover extent among all months on record.
- The snow cover extent for the Northern Hemisphere during the winter (December–February) was the 14th largest on record. The North American winter snow cover extent was the fourth smallest, partially driven by low snow totals across the contiguous United States. The Eurasian winter snow cover extent was the fourth largest on record, due to the heavy snowfall observed across central and eastern Europe during January and February.
- Precipitation was variable across the globe during February. Dryness prevailed across much of Western Europe during February. France reported its driest February since 1959, Spain reported its driest since 2000, and England had its driest February since 1998. Rainfall was much heavier than average in southeastern Australia, with major flooding occurring in Queensland, New South Wales, and Victoria. This rainfall was associated in part with La Niņa.
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 2010 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.
Temperature anomalies for February 2012 and December 2011 – February 2012 are shown on the dot maps below. The dot maps on the left provide 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 maps on the right are 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.
In the atmosphere, 500-millibar height pressure anomalies correlate well with temperatures at the Earth's surface. The average position of the upper-level ridges of high pressure and troughs of low pressure—depicted by positive and negative 500-millibar height anomalies on the February 2012 map—is generally reflected by areas of positive and negative temperature anomalies at the surface, respectively.
During February 2012, many land areas around the globe, especially in the Northern Hemisphere, saw extreme warm or extreme cold temperatures compared with their averages. The temperature departures were due at least in part to a negative phase of the Arctic Oscillation during the first half of the month that was associated with a long and severe cold snap to Central and Eastern Europe. Anomalous cold stretched across most of the 40°N–55°N latitude belt of Europe and Asia. It was also much colder than normal across eastern Russia to the northeast. Conversely, all of Canada, the eastern half of the United States, and north central Russia saw much warmer-than-average temperatures. The average Northern Hemisphere land temperature was 0.31°C (0.56°F) above normal, the 45th warmest February for this region since records began in 1880. February 2012 also marks the coolest February since 1994 for the Northern Hemisphere. In the Southern Hemisphere, which contains much less land mass than its counterpart, Australia had cooler-than-average temperatures while parts of southern South America were warmer than normal, contributing to the February Southern Hemisphere temperature anomaly of 0.56°C (1.01°F)—the 12th warmest February on record. Combining the two hemispheres, the average global temperature over land in February was 5.58°C (37.68°F), which is 0.38°C (0.68°F) above the 20th century average and the 37th warmest February on record.
- The average Febraury temperature across Spain was 2.5°C (4.5°F) below the 1971–2000 period of reference, representing the fourth coldest February on record since 1961.The average minimum temperature for the month was the lowest since 1956.
- Austria's average February temperature was 3.9°C (7.0°F) below the 1971–2000 period of reference, the coldest February on record since 1986. It is notable that the temperature during the first half of the month was about 10°C (18.0°F) below average and then warmed susbstantially during the latter half.
- Both Scotland and Northern Ireland reported their warmest Februaries since 1998. For Northern Ireland, this marks it fourth warmest February on record.
- Germany experienced its coldest February since 1986 and 15th coldest since records began in 1881. The average temperature was 3.4°C below the 1981–2010 period of reference.
- According to Environment Canada, the average temperature in Ontario during February "rivaled record values set in 1998". Average temperatures across the region ranged from 3.7°C to 6.8°C (6.7°F to 12.2°F) above average.
- Australia reported its lowest nationally-averaged minimum temperature since 1990. It was the eighth coolest since records began in 1950. The state of Queensland in the northeast of the country observed its third coolest February minimum temperatures on record while Tasmania in the southeast experienced its eighth warmest.
Global ocean temperatures remained fairly steady in comparison with recent months. According to NOAA's Climate Prediction Center, La Niña continued to weaken across the east central equatorial Pacific Ocean, as is evident by the above blended land and sea surface temperature anomaly dot map. The cooler-than-average temperatures are warmer in this region compared with January, and in fact above average in parts of the eastern equatorial Pacific. Warmer-than-average temperatures were also observed across the north central Pacific, the North Atlantic, much of the eastern Indian Ocean, and portions of the mid-latitude Southern oceans. During February, the average temperature across the world's oceans was 0.36°C (0.65°F) above the long-term average, the 12th warmest February on record. By comparison, February 2011, which also saw a weakening La Niña, ranked as 10th warmest. The current La Niña is expected to dissipate by the end of April this year.
(out of 133 years)
|Land||+0.38 ± 0.34||+0.68 ± 0.61||Warmest||37th||2002||+1.65||+2.97|
|Ocean||+0.36 ± 0.04||+0.65 ± 0.07||Warmest||12th||1998, 2010||+0.56||+1.01|
|Land and Ocean||+0.37 ± 0.11||+0.67 ± 0.20||Warmest||22nd||1998||+0.84||+1.51|
|Land||+0.31 ± 0.37||+0.56 ± 0.67||Warmest||45th||2002||+2.20||+3.96|
|Ocean||+0.32 ± 0.04||+0.58 ± 0.07||Warmest||10th||2010||+0.57||+1.03|
|Ties: 2001, 2011|
|Land and Ocean||+0.32 ± 0.17||+0.58 ± 0.31||Warmest||30th||2002||+1.08||+1.94|
|Ties: 1934, 1941, 1944|
|Land||+0.56 ± 0.13||+1.01 ± 0.23||Warmest||12th||2010||+1.12||+2.02|
|Ocean||+0.40 ± 0.04||+0.72 ± 0.07||Warmest||13th||1998||+0.59||+1.06|
|Land and Ocean||+0.42 ± 0.06||+0.76 ± 0.11||Warmest||13th||2010||+0.66||+1.19|
|Ties: 1992, 1999|
Two large-scale climate patterns—the Arctic Oscillation (AO) and La Niña—influenced temperatures around the globe during December 2011–February 2012 (boreal winter/austral summer). The AO, which impacts weather patterns in the Northern Hemisphere, was primarily positive during the three-month period, keeping cold Arctic air tightly contained in the polar regions; however, there was a three-week period during late January to mid-February when the AO turned negative and was associated with record-breaking cold and snow to Central and Eastern Europe. On average, warmer-than-normal temperatures were observed across most of North America, most of northern Europe and Asia, and southern South America. Cooler-than-normal temperatures were felt across western and central Alaska, far eastern Russia, the Middle East, central and eastern mainland Asia, the southern half of Australia, and northwestern Africa. Overall, the average December–February 2011/12 temperature over land surfaces was 0.59°C (1.06°F) above the 20th century average, marking the 20th warmest such period on record.
- Norway reported its 23rd warmest winter in its 113-year period of record, with the average temperature 2.0°C (3.6°F) above normal.
- The contiguous United States reported its fourth mildest winter since records began in 1895, with the average temperature 2.2°C (3.9°F).
- Australia reported its 11th coolest maximum and 15th coolest minimum summer temperatures in the country's 63-year period of record. La Niña conditions contributed to the second coolest February minimum temperature for the southeastern state of New South Wales.
Across the oceans, cool La Niña waters influenced sea surface temperatures during December–February. Even so, the globally-averaged temperature was 0.34°C (0.61°F) above the 20th century average, the 15th warmest such period on record. Combining land and ocean temperatures, the global average temperature was the 17th warmest on record, 0.41°C (0.74°F) above average.
(out of 133 years)
|Land||+0.59 ± 0.21||+1.06 ± 0.38||Warmest||20th||2007||+1.42||+2.56|
|Ties: 1944, 1993|
|Ocean||+0.33 ± 0.04||+0.59 ± 0.07||Warmest||15th||1998||+0.57||+1.03|
|Land and Ocean||+0.41 ± 0.09||+0.74 ± 0.16||Warmest||17th||2007||+0.74||+1.33|
|Land||+0.61 ± 0.23||+1.10 ± 0.41||Warmest||26th||2007||+1.67||+3.01|
|Ocean||+0.34 ± 0.05||+0.61 ± 0.09||Warmest||12th||2010||+0.57||+1.03|
|Coolest||122nd||1904, 1910, 1913||-0.46||-0.83|
|Land and Ocean||+0.44 ± 0.13||+0.79 ± 0.23||Warmest||14th||2007||+0.96||+1.73|
|Land||+0.53 ± 0.13||+0.95 ± 0.23||Warmest||14th||2010||+0.95||+1.71|
|Ocean||+0.34 ± 0.04||+0.61 ± 0.07||Warmest||22nd||1998||+0.60||+1.08|
|Land and Ocean||+0.37 ± 0.07||+0.67 ± 0.13||Warmest||19th||1998||+0.64||+1.15|
Falling within the December 2011–February 2012 period discussed above, the January–February 2012 temperature anomalies were rather similar to the 2011/12 boreal winter/austral summer months around the globe. For the year to date, the average global land surface temperature ranked as the 33rd warmest such period on record, while the average sea surface temperature ranked as 14th warmest. Combined, the globally-averaged temperature across all land and ocean surfaces was 0.37°C (0.67°F) above the 20th century average, the 20th warmest January–February on record.
(out of 133 years)
|Land||+0.43 ± 0.26||+0.77 ± 0.47||Warmest||33rd||2002||+1.50||+2.70|
|Ocean||+0.34 ± 0.04||+0.61 ± 0.07||Warmest||14th||1998||+0.56||+1.01|
|Land and Ocean||+0.37 ± 0.10||+0.67 ± 0.18||Warmest||20th||2007||+0.74||+1.33|
|Land||+0.38 ± 0.29||+0.68 ± 0.52||Warmest||39th||2002||+1.96||+3.53|
|Ocean||+0.33 ± 0.05||+0.59 ± 0.09||Warmest||10th||2010||+0.55||+0.99|
|Ties: 2006, 2009|
|Land and Ocean||+0.35 ± 0.15||+0.63 ± 0.27||Warmest||24th||2002||+0.98||+1.76|
|Ties: 1988, 1996|
|Land||+0.58 ± 0.13||+1.04 ± 0.23||Warmest||12th||2010||+1.02||+1.84|
|Ties: 1999, 2001|
|Ocean||+0.36 ± 0.04||+0.65 ± 0.07||Warmest||17th||1998||+0.59||+1.06|
|Ties: 1980, 1992, 2000|
|Land and Ocean||+0.39 ± 0.06||+0.70 ± 0.11||Warmest||16th||1998, 2010||+0.64||+1.15|
The most current data may be accessed via the Global Surface Temperature Anomalies page.
Images of sea surface temperature conditions are available for all weeks during 2012 from the weekly SST page.
The maps below represent anomaly values based on the GHCN dataset of land surface stations using a base period of 1961–1990. During February 2012, above-average precipitation fell over areas that included part of the south central United States and Mexico, portions of South America, the Philippines, southeastern Australia, and Madagascar, where Tropical Cyclone Giovanna dropped heavy rainfall. Lower-than-average precipitation was observed over areas that included much of Western Europe, eastern Brazil, and the eastern United States.
During the seasonal period December 2011 – February 2012, above-average precipitation fell over areas that included much of Northern and Eastern Europe, Malaysia, southeastern Australia, parts of northern South America, and the south central United States. Drier-than-average conditions were observed across several regions during December 2011 – February 2012, including southern Europe, eastern Brazil, and Pakistan.
- In Western Europe, France reported its driest February since 1959, Spain reported its driest since 2000, and England had its driest February since 1998.
- Norway reported its 35th wettest February and 22nd wettest winter, at 35 percent and 25 percent above average, respectively, since records began in 1900.
- Precipitation was variable for the summer across New Zealand. According to NIWA, it was very wet across the North Island and extremely dry over the southwestern portion of South Island; the northern towns of Nelson and Takaka on South Island reported their wettest summers on record.
- February rainfall in Australia was 11.9 percent below average, ranking as the 44th driest February on record. For the entire summer season (December–February), however, rainfall was 16 percent above average for the country as a whole, making this the 22nd wettest summer since records began in 1900. The eastern Australian states of Queensland, New South Wales, and Victoria saw heavy flooding during February due to the monsoonal trough and ongoing La Niña effects.
Additional details on flooding and drought events around the world can also be found on the February 2012 Global Hazards page.
Peterson, T.C. and R.S. Vose, 1997: An Overview of the Global Historical Climatology Network Database. Bull. Amer. Meteorol. Soc., 78, 2837-2849.
Quayle, R.G., T.C. Peterson, A.N. Basist, and C. S. Godfrey, 1999: An operational near-real-time global temperature index. Geophys. Res. Lett., 26, 333-335.
Smith, T.M., and R.W. Reynolds (2005), A global merged land air and sea surface temperature reconstruction based on historical observations (1880-1997), J. Clim., 18, 2021-2036.
Smith, et al (2008), Improvements to NOAA's Historical Merged Land-Ocean Surface Temperature Analysis (1880-2006), J. Climate., 21, 2283-2293.