Climate of 2004 February in Historical Perspective Including Boreal Winter

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* Based on preliminary data for December 2003 – February 2004, global average combined land and sea surface temperature was third warmest on record, and fourth warmest for February 2004
* December – February temperatures were much above average throughout much of western and central Asia as well as parts of Canada with below average temperatures in northern Australia, Mexico and the eastern U.S.
* Precipitation during December – February was above average across most of Europe, the Great Plains of the U.S. and northern Australia with drier than average conditions in Ireland, the eastern U.S. and Argentina
* Near-normal SSTs across the central and eastern equatorial Pacific basin are indicative of neutral ENSO conditions.

Introduction

Using a 1961-1990 base period, the maps indicate above average temperatures in the central U.S., most of Europe and Japan while cooler than average temperatures occurred in northern Australia and northern Argentina during winter and February 2004.

The mean position of upper level ridges of high pressure and troughs of low pressure are generally reflected by areas of positive and negative temperature anomalies at the surface, respectively

Temperature Rankings

February Anomaly Rank Warmest Year on Record Global

Land +1.08°C (+1.94°F) 5th warmest 1998 (+0.1.61°C/2.90°F) Ocean +0.43°C (+0.77°F) 2nd warmest 1998 (+0.53°C/0.95°F) Land and Ocean +0.62°C (+1.12°F) 4th warmest 1998
(+0.85°C/1.53°F)

February Northern Hemisphere

Land +1.19°C (+2.14°F) 7th warmest 2002 (+2.01°C/3.62°F) Ocean +0.44°C (+0.79°F) 2nd warmest 1998 (+0.55°C/1.00°F) Land and Ocean +0.74°C (+1.33°F) 5th warmest 1998 (+1.10°C/1.98°F)

Winter 2003-2004 Global Anomaly Rank Warmest Year on Record

Land +0.89°C (+1.60°F) 5th warmest 2002 (+1.08°C/1.94°F) Ocean +0.44°C (+0.79°F) 2nd warmest 1998 (+0.56°C/1.01°F) Land and Ocean +0.57°C (+1.03°F) 3rd warmest 1998 (+0.71°C/1.28°F)

Precipitation

The maps below represent anomaly values based on the GHCN data set of land surface stations using a base period of 1961-1990. The map to the left is precipitation anomalies measured in millimeters, the map to the right is the percentage of average (1961-1990) precipitation. During December – February 2004, much above average precipitation fell across the Mississippi Valley in the U.S., eastern Europe and Indonesia. Below average precipitation was observed in Iberian Peninsula, Ireland and India.

ENSO SST Analysis

Sea surface temperatures were near-normal over much of the central and eastern equatorial Pacific (as shown in the adjacent animation of weekly sea surface temperature anomalies). A consensus of indices suggest neutral ENSO conditions

More information: www.ncdc.noaa.gov/oa/climate/research/2004/feb/global.html