Global Analysis - April 2007


Global Highlights:

  • Based on preliminary data, globally averaged combined land and sea surface temperature was the warmest on record for January-April year-to-date period and third warmest for April.
  • Global land surface temperature was warmest on record in April. Temperatures were above average in Europe, Alaska, western U.S., eastern Brazil, northwestern Africa, and most of Asia. Cooler-than-average conditions occurred in the Middle East Region and the eastern half of the contiguous U.S.
  • Precipitation during April 2007 was above average in the Northeast region of the contiguous U.S. and most of South America. Drier than average conditions were observed in Japan, southeastern U.S., southeastern China and most of Europe.
  • ENSO conditions remained in a neutral phase during April.

Contents of this Section:

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The data presented in this report are preliminary. Ranks and anomalies may change as more complete data are received and processed. The most current data may be accessed via the Global Surface Temperature Anomalies page.
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Top of PageIntroduction

Temperature anomalies for April 2007 are shown on the dot maps below. The dot map, below left, provides a spatial representation of anomalies calculated from the Global Historical Climatology Network (GHCN) data set of land surface stations using a 1961-1990 base period. The dot map, below right, is a product of a merged land surface and sea surface temperature anomaly analysis developed by Smith and Reynolds (2005). Temperature anomalies with respect to the 1961-1990 mean for land and ocean are analyzed separately and then merged to form the global analysis. Additional information on this product is available.

Anomalously warm temperatures have covered much of the globe throughout the year. The January-April 2007 map of temperature anomalies shows the presence of warmer than average temperatures across all land areas, with the exception of Alaska. Additional information on Alaska temperatures are available on the U.S. National page. Warmer than average Sea Surface Temperatures (SST) occured in the equatorial Pacific, North and South Atlantic and the Indian Ocean. Cooler than average conditions were observed in the northeastern Pacific and some areas in the South Pacific.

During April, there were above average temperatures across Europe, Alaska, western U.S., eastern Brazil, northwestern Africa, and most of Asia. Cooler-than-average conditions occurred in the Middle East Region and the eastern half of the contiguous U.S. Warmer than average SSTs occurred in the Atlantic Ocean, North Indian Ocean, and the Northwestern Pacific Ocean. In the Niño regions, SST anomalies were in the range of average or slightly below average with the exception of the Niño 4 region where SST anomalies were slightly above average. These conditions are indicative of a persisting neutral ENSO phase. Please see the latest ENSO discussion for additional information.

Current month's Land SurfaceTemperature Dot map
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Current month's blended Land and sea surface Temperature Dot map
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The mean position of upper level ridges of high pressure and troughs of low pressure (depicted by positive and negative 500-millibar height anomalies on the April map) are generally reflected by areas of positive and negative temperature anomalies at the surface, respectively. For other Global products see the Climate Monitoring Global Products page.

Images of sea surface temperature conditions are available for all weeks during 2007 at the weekly SST page.

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Top of Page Temperature Rankings and Graphics

Effective with the February 2006 report, NCDC transitioned from the use of the Operational Global Surface Temperature Index (Quayle et al. 1999) to the blended land and ocean dataset developed by Smith and Reynolds (2005). The differences between the two methods are discussed in Smith et al. (2005).

April 2007 ranked as the third warmest April since records began in 1880 for combined global land and ocean surface temperatures. The April land surface temperature ranked warmest on record, while ocean surface temperature ranked seventh warmest in the 127-year record. For the January-April year-to-date period, the global surface temperature ranked warmest on record.

Current Month / Year-to-date
April Anomaly Rank Warmest (or Next
Warmest) Year on Record
Ties

Global

Land
Ocean
Land and Ocean

+1.37°C (+2.47°F)
+0.41°C (+0.74°F)
+0.67°C (+1.21°F)

warmest
7th warmest
3rd warmest

2000 (+1.30°C/2.34°F)
1998 (+0.53°C/0.95°F)
1998 (+0.70°C/1.26°F)

2001

Northern Hemisphere

Land
Ocean
Land and Ocean


+1.57°C (+2.83°F)
+0.43°C (+0.77°F)
+0.86°C (+1.55°F)


2nd warmest
4th warmest
warmest


2000 (+1.66°C/2.99°F)
2004 (+0.53°C/0.95°F)
2005 (+0.81°C/1.46°F)


2002

Southern Hemisphere

Land
Ocean
Land and Ocean


+0.79°C (+1.42°F)
+0.40°C (+0.72°F)
+0.45°C (+0.81°F)


9th warmest
9th warmest
8th warmest


1992 (+1.41°C/2.54°F)
1998 (+0.59°C/1.06°F)
1988 (+0.63°C/1.13°F)


1983

Global Land and Ocean Triad plot
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Global Hemisphere Triad plot
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January-April Anomaly Rank Warmest (or Next
Warmest) Year on Record
Ties

Global

Land
Ocean
Land and Ocean

+1.35°C (+2.43°F)
+0.44°C (+0.79°F)
+0.69°C (+1.24°F)

warmest
6th warmest
warmest

2002 (+1.29°C/2.32°F)
1998 (+0.53°C/0.95°F)
2002 (+0.68°C/1.22°F)


Northern Hemisphere

Land
Ocean
Land and Ocean


+1.56°C (+2.81°F)
+0.46°C (+0.83°F)
+0.88°C (+1.58°F)


warmest
3rd warmest
warmest


2002 (+1.54°C/2.77°F)
2004 (+0.50°C/0.90°F)
2002 (+0.83°C/1.49°F)


2005

Southern Hemisphere

Land
Ocean
Land and Ocean


+0.72°C (+1.30°F)
+0.43°C (+0.77°F)
+0.47°C (+0.85°F)


4th warmest
7th warmest
6th warmest


2005 (+0.89°C/1.60°F)
1998 (+0.56°C/1.01°F)
1998 (+0.61°C/1.10°F)


2001

Global Land and Ocean Triad plot
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Global Hemisphere Triad plot
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The most current data may be accessed via the Global Surface Temperature Anomalies page.

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Top of Page Precipitation

The maps below represent anomaly values based on the GHCN data set of land surface stations using a base period of 1961-1990. During April 2007, above average precipitation fell over areas that include the Northeast region of the contiguous U.S. and most of South America. Drier than average conditions were observed in Japan, southeastern U.S., southeastern China and most of Europe. Additional details on flooding and drought can also be found on the April Global Hazards page.

Current month's Precipitation Dot Map in Millimeters larger image
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Current month's Precipitation Percent Departure Dot Map in Millimeters larger image
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Top of Page ENSO SST Analysis




Last week of the month's ENSO condtions Map
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  • Sea Surface Temperature anomalies were near average or slightly cooler than average across the central and eastern equatorial Pacific, indicative of a neutral ENSO phase (shown in the adjacent animation of weekly sea surface temperature anomalies). A comprehensive summary of April 2007 ENSO conditions can be found on the ENSO monitoring page. For the latest advisory on ENSO conditions go to NOAA's Climate Prediction Center (CPC) and the CPC ENSO Diagnostic Discussion.


  • Images of sea surface temperature conditions are available for all weeks since 2003 at the weekly SST page.

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Top of Page References


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.

Citing This Report

NOAA National Climatic Data Center, State of the Climate: Global Analysis for April 2007, published online May 2007, retrieved on November 27, 2014 from http://www.ncdc.noaa.gov/sotc/global/2007/4.