Global Analysis - April 2005
Note: The data presented in this report are preliminary. Ranks and anomalies may change as more complete data are received and processed. Effective September 2012, the GHCN-M version 3.2.0 dataset of monthly mean temperature replaced the GHCN-M version 3.1.0 monthly mean temperature dataset. Beginning with the August 2012 Global monthly State of the Climate Report, released on September 17, 2012, GHCN-M version 3.2.0 is used for NCDC climate monitoring activities, including calculation of global land surface temperature anomalies and trends. For more information about this newest version, please see the GHCN-M version 3.2.0 Technical Report.
*The GHCN-M version 3.1.0 Technical Report was revised on September 5, 2012 to accurately reflect the changes incorporated in that version. Previously that report incorrectly included discussion of changes to the Pairwise Homogeneity Algorithm (PHA). Changes to the PHA are included in version 3.2.0 and described in the version 3.2.0 Technical Report. Please see the Frequently Asked Questions to learn more about this update.
Global Highlights:
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Contents of this Section: |
| 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. |
Temperature anomalies for April 2005 are shown on the two maps
below. The dot map on the left uses anomalies that were calculated
from the Global Historical Climatology Network (GHCN) data set of
land surface stations using a 1961-1990 base period. The map on the
right is a weekly product based on data from the Comprehensive
Ocean-Atmosphere Data Set (COADS) of SST data. During April, there
were above average temperatures over much of Alaska, Canada,
Mexico, Algeria, the majority of Europe, the Middle East, eastern
China, Australia, as well as from the northern Great Plains to the
northeastern U.S. Cooler than average temperatures were observed
over the southern U.S., coastal Argentina, far western Alaska,
India and parts of western Australia. |
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| Above average SSTs are
also evident in the product above. Slightly warmer than average
conditions occurred over large parts of the eastern and central
Pacific, reflecting transitioning conditions from an El Niño
warm phase to a neutral phase. SSTs were also warmer than average
in much of the northern Pacific and northern Atlantic. Cooler than
average SSTs were observed over areas northwest of the Hawaiian
Islands, off the eastern seaboard of the U.S., and off the east
coast of Japan. 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 2005 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 months during 2005 at the weekly SST page |
|
| Current Month / Year-to-date |
| April | Anomaly | Rank | Warmest Year on Record |
|---|---|---|---|
| Global Land Ocean Land and Ocean |
+1.27°C (+2.29°F) +0.41°C (+0.74°F) +0.67°C (+1.21°F) |
1st warmest 3rd warmest 2nd warmest |
2nd - 1998 (+1.23°C/2.21°F) 1998 (+0.51°C/0.92°F) 1998 (+0.72°C/1.30°F) |
| Northern Hemisphere Land Ocean Land and Ocean |
+1.26°C (+2.27°F) +0.47°C (+0.85°F) +0.79°C (+1.42°F) |
1st warmest 1st warmest 1st warmest |
2nd - 1998 (+1.25°C/2.25°F) 2nd - 2004 (+0.46°C/0.83°F) 2nd - 1998 (+0.77°C/1.39°F) |
| Southern Hemisphere Land Ocean Land and Ocean |
+1.06°C (+1.91°F) +0.38°C (+0.68°F) +0.51°C (+0.92°F) |
2nd warmest 7th warmest 3rd warmest |
1998 (+1.07°C/1.93°F) 1998 (+0.56°C/1.01°F) 1998 (+0.66°C/1.19°F) |
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| January-April | Anomaly | Rank | Warmest Year on Record |
|---|---|---|---|
| Global Land Ocean Land and Ocean |
+0.97°C (+1.75°F) +0.43°C (+0.77°F) +0.59°C (+1.06°F) |
4th warmest 2nd warmest 4th warmest |
2002 (+1.37°C/2.47°F) 1998 (+0.51°C/0.92°F) 1998 (+0.72°C/1.30°F) |
| Northern Hemisphere Land Ocean Land and Ocean |
+0.93°C (+1.67°F) +0.46°C (+0.83°F) +0.65°C (+1.17°F) |
10th warmest 2nd warmest 4th warmest |
2002 (+1.60°C/2.90°F) 1998 (+0.51°C/0.92°F) 2002 (+0.86°C/1.55°F) |
| Southern Hemisphere Land Ocean Land and Ocean |
+0.90°C (+1.62°F) +0.43°C (+0.77°F) +0.52°C (+0.94°F) |
warmest 5th warmest 2nd warmest |
2nd - 1998 (+0.87°C/1.57°F) 1998 (+0.54°C/0.97°F) 1998 (+0.60°C/1.10°F) |
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The most current data may be accessed via the Global Surface Temperature Anomalies page.
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 2005, above average precipitation fell over the northeastern
U.S., the lower Mississippi Valley of the U.S., north-central South
America, Puerto Rico, western Europe, southern India and parts of
western Australia. Below average precipitation was observed over
the southern Great Plains of the U.S., Alaska, the majority of
eastern and southeastern Asia, much of Australia, Madagascar and
the Iberian Peninsula. |
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|
|
Peterson, T.C. and R.S. Vose, 1997: An Overview of the Global
Historical Climatology Network Database. Bull. Amer. Meteorol.
Soc., 78, 2837-2849. |
