New Web Site Images Show Shifts in Global Sea Temperatures
The Web address is:
“The images on this site will be valuable not only for scientists, but also for educational purposes and for the media,” said Nigel Houghton, ATSR Data Services Manager at RAL.
The gallery shows monthly maps from May 1995 to the current date (with the exception of January - June 1996 when no data were recorded) and will be updated regularly as new raw data becomes available. Animated versions showing how sea surface temperatures varied over each year have also been included.
Data for the images came from the UK-built ATSR-2 (Along Track Scanning Radiometer) instrument on the European Remote-Sensing Satellite ERS-2, which is operated by the European Space Agency. The data was processed at CLRC Rutherford Appleton Laboratory.
The period covered by this gallery has been particularly significant for climate researchers since it coincided with the rise and decline of one of the most active El Nino events on record. El Nino is named after the Christ Child since it often arrives around Christmas time. During these periodic events, there is a remarkable switch in weather patterns, most notably over the Pacific Ocean.
In normal conditions, trade winds blowing across the Pacific Ocean push warm water across from the coast of Peru to the Western Pacific. This water is replaced by colder water rising up from deeper within the Ocean. Throughout 1995, normal conditions prevailed and the images for that year show a tongue of cooler water stretching away from the coast of South America towards the western Pacific.
During an El Nino event, the trade winds diminish and the enormous pool of warm water, which normally surrounds Malaysia and Indonesia, transfers thousands of miles eastwards to the coast of the Americas. Here it brings unusually heavy rains, while drought occurs in the western Pacific. This El Nino can first be seen in the gallery in January 1997 when the tongue of cooler water disappears and continues until June 1998 when the cooler water reappears.
Since June 1998, the cooler waters have become even more pronounced than normal and a La Nina event has begun. During times of a La Nina, the warm water is driven further westwards towards Australia and Indonesia often causing extensive floods in the western Pacific and drought in the Americas.
Monthly maps of sea surface temperatures derived from the ATSR-1 instrument on the ERS-1 satellite (August 1991 - June 1995) will start to become available later this year.
The development of the ATSR instruments was funded by the Natural Environment Research Council (NERC). A new, improved version, known as the Advanced ATSR (AATSR), has just completed tests at RAL prior to installation by Matra Marconi Space (Bristol) on the European Space Agency's Envisat satellite.
The ATSR instruments were developed for the European Space Agency by a consortium comprising:
The ATSR team at RAL has been involved in all aspects of the project from instrument conception, design and construction through to the processing of the huge amounts of data from the instrument and use of the data in research into relevant areas within the field climatology such as global warming.
RAL's Space Science Department is involved in many European and international space missions, including ERS-1 and 2, Envisat, Cassini-Huygens, SOHO and ISO.