Geneva, Thursday, 17 December -- The earth's global temperature in 1998 will be the highest since 1860, according to the World Meteorological Organization (WMO). The global mean surface temperature is estimated to be 0.58 oC above the recent long-term average based on the period 1961-1990. As we approach the end of the century, global temperatures are almost 0.7 oC above those at the end of the 19th century.
It will be the 20th consecutive year with an above normal global surface temperature. The ten warmest years have all occurred since 1983, with seven of them since 1990. As of October, new monthly temperature records have been set in each of the past 18 months. The previous warmest year,1997, was 0.43 oC above average.
The regional temperature patterns (January through November) show all of the continents with above average temperatures, except for the northern sections of Eurasia. In the United States of America, spring and summer heat and drought caused massive wildfire outbreaks in Florida and damage to crops from the southern plains to the southeast. April-June was the driest period in 104 years of record in Florida, Texas, Louisiana, and New Mexico, and May-June was the warmest period on record.
February was the warmest in many regions of France and the UK for more than 100 years. A record-breaking heat wave during June in central Russia caused more than 100 deaths and started huge fires.
In New Zealand, at least five months of the year had unusually warm temperatures. Qatar experienced the hottest summer ever for four consecutive months from June to September, due principally to high minimum temperatures. A severe heat wave prevailed over many parts of India resulting in great loss of life in May 1998. There was widespread drought affecting large areas of Brazil inducing extensive wildfires. Rainfall deficits in some cities in Chile during July made it the driest in a century. Fiji and eastern New Zealand also experienced droughts.
Unusually low temperatures were recorded during January in Argentina and Uruguay, and during June in the USA. Also, during November, much of Europe experienced extremely cold conditions, which spread eastward through Siberia and into Korea and the northern sections of Japan by the end of the month.
Higher in the atmosphere, where regular measurements are made by instruments on weather balloons and satellites, record high temperatures also occurred. From the surface to 7 km altitude, record temperatures in 1998 were 0.47 =BAC higher than the average of the last 20 years, making 1998 by far the warmest year. In the lower stratosphere, 1998 was colder than usual, though not quite as cold as in 1995-1997 period.
Computer models of the atmosphere show that cold conditions in the lower stratosphere result from both increased carbon dioxide and depleted ozone. The ozone deficiency during the austral-spring season, September through November 1998, was the largest and strongest ever recorded. The area covered by the ozone-hole lasted for more than 100 continuous days, which was a new record. The area exceeded 25 million km2 for 20 days while in previous seasons the area exceeded 20-22 million km2 in area only for a few days. Poleward of 60 degrees South, the ozone deficiency was 25% more this season than the average of the previous seasons in the 1990s. Globally, carbon dioxide concentrations continued to increase at a rate of 1.5 parts per million per year.
Over the oceans, a slowly fading El Niño and the unprecedented warmth of the Indian Ocean contributed to this record warm year. The El Niño event which started in 1997,continued to influence the climate in 1998 including extremely dry conditions and fires in Indonesia, drought in Guyana and Papua New Guinea, and extensive flooding in Ecuador, Peru, and Kenya early in 1998. Devastating floods in China were linked to the final stages of the El Niño. Lingering El Niño conditions in the east Pacific were associated with extremely dry conditions in Mexico and southern USA.
The central equatorial Pacific warm El Niño waters gave way to colder than normal sea surface temperatures (La Nina condition) by mid-year. The switch to La Niña conditions was associated with extremely heavy rains in the West Pacific triggering landslides and floods in Indonesia.
El Niño contributed to the late start of the 1998 Atlantic Hurricane season which under the influence of La Niña, ended as one of the deadliest in history with 14 named storms. Hurricane Mitch triggered massive flooding and landslides in late October that killed over 9 000 people, displaced another 2.4 million, and damaged or destroyed over 130 000 homes in Central America.
In China, preliminary estimates show that 22 provinces suffered from severe flood disasters. With an affected area covering 8.5 million hectares, the death toll was more than 3 000 with a record number of rivers and lakes flooded.
Floods in India and Bangladesh took over 2 800 lives. In Bangladesh, three major floods occurred during July and August, leaving about 50% of the country under water, up to 3 meters deep, for periods of up to 67 days. Another 250 died in Nepal. There were also significant floods in the Republic of Korea and Vietnam, the Philippines, the Russian Federation, and Sudan. In January, eastern Canada suffered from the longest-duration ice storm in its history. More than 100 mm of freezing rain and drizzle fell for more than 80 hours.
The preliminary estimates for 1998 are based on observations up to mid-December from a network of ships, buoys and land-based weather stations. More extensive information will be made available in early January during the annual meeting of the American Meteorological Society in Dallas, Texas, USA.
Prof. G.O.P. Obasi, Secretary General of WMO, called upon the world community "to heed the anomalies and maximize their effort to implement the resolutions of the Fourth Conference of Parties of the UN Convention on Climate Change, particularly the resolution urging for the enhancement of the Global Climate Observing Systems." He added that "the Global estimates such as this are only possible thanks to the long-standing exchange of weather information facilitated by WMO through its Member countries and in particular the national Meteorological and Hydrological Services."
(*A joint Press Release issued in collaboration with the Hadley Centre of the UK Meteorological Office, the Climatic Research Unit at the University of East Anglia, UK and in the USA: the National Climatic Data Center in Asheville; the Climate Prediction Center in Washington; NASA Goddard Institute for Space Studies; NASA/Marshal Space Flight Center; University of Alabama in Huntsville; and the International Research Institute in New York. Other contributing WMO Member countries were Canada, Chile, China, Colombia, Ecuador, Fiji, Germany, India, Indonesia, Japan, New Zealand, Peru, the Philippines and Qatar)
For more information, please contact:
Mr. Taysir M. Al-Ghanem, Information and Public Affairs Office
World Meteorological Organization
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CH 1211 Geneva 2 (Switzerland)
Tel.+(41 22) 730 8315 - Fax.+(41 22) 733 2829
Internet website: http://www.wmo.ch