The Global Climate 2000

The global average surface temperature is likely to be about 0.32°C above the climatological average for the period 1961-1990.

This is similar to 1999, which was the 5th warmest year in the past 140 years, according to records maintained by Members of the World Meteorological Organization (WMO). The warmer years were 1998, 1997, 1995 and 1990. The ten warmest years have all occurred since 1983, with eight of these occurring since 1990. The year 2000 has continued the run of warm years in spite of the persistent cooling influence of the tropical Pacific La Niņa.

As a new century begins, the global mean temperature is 0.6°C above those at the start of the 20th century. The year 2000 will be the 22nd consecutive year with the global mean surface temperature above the 1961-1990 normal. Most of the non-tropical Northern Hemisphere experienced above average temperatures in each season.

However, the eastern tropical Pacific was colder than usual throughout most of the year as La Niņa was strong at the beginning of the year, weakened during July and August and showed signs of reappearing at year’s end. The remainder of the tropics and the non-tropical Southern Hemisphere had a variety of anomalies, with a predominance of warmth.

In the atmospheric layer from the surface to 8 km altitude, routine temperature measurements made by instruments on weather balloons and satellites showed that the year 2000 was similar to 1999 in being very close to the 1979-1990 average. In the lower stratosphere (8 km to 12 km altitude), 2000 was slightly less cold than 1999 (the coldest year in the 36-year record) but was still nearly 1° C colder than the 1979-1990 average.

Precipitation patterns throughout the tropics were dominated by typical La Niņa conditions during the first half and at the end of the year. Indonesia, the tropical Indian Ocean and western tropical Pacific all experienced greatly enhanced precipitation during the two periods, while the central tropical Pacific experienced virtually no rainfall.

Other regions influenced by La Niņa included Australia, north-east South America and southern Africa, which experienced enhanced precipitation during the periods. Enhanced monsoonal precipitation also affected southern Asia. Conversely, La Niņa contributed to below-normal precipitation over equatorial east Africa and along the Gulf Coast of the United States.

During the year 2000, the Atlantic experienced an above average number of hurricanes and tropical storms (15, the average is 10), while the Pacific experienced only 22 storms, which is below the average of approximately 28. Several of these storms produced extreme amounts of precipitation, flooding and damage.

Most notable were hurricanes Keith and Gordon causing severe damage in Central America and tropical storm Leslie producing excessive amounts of precipitation in Florida in the United States.

In the Pacific, Typhoon Saomai caused record breaking rainfall over parts of Japan, Typhoon Prapiroon struck the coast of the Korean peninsula bringing over 30 hours of relentless rainfall, and two major typhoons made landfall on Viet Nam resulting in extreme rains over the SE Asian area. One major cyclone formed over the Bay of Bengal and struck the southern Indian peninsula in late November causing severe property damage from rainfall and wind.

Arguably the most devastating cyclones of the year were Eline, Gloria and Hudah which struck Madagascar, Mozambique and parts of southern Africa causing severe flooding and loss of life. Finally cyclone Steve caused major damage and record flooding in Australia in late February.

Severe rains resulting in flooding occurred in several other areas of the world as well. Most notably, severe flooding occurred in southern Switzerland and north-eastern Italy in October, in Colombia from June to August, and in India, Bangladesh, Cambodia, Thailand, Laos and Viet Nam from monsoon rainfall, all resulting in loss of life and severe property damage.

More than 10 million people were affected in India alone with over 650 deaths. Flooding and mudslides also caused damage and loss of life in Central and South America in May and June. Torrential rains triggered mudslides killing thirteen people in Guatemala. In Nicaragua, the Rama River rose 4.5 meters and spilled over its banks on June 21, flooding most of Rama City, a town of 10,000 people.

In Australia, extensive areas experienced one of their wettest-ever January-April periods, with record rainfall and flooding in many locations. Some parts of western Queensland in Australia received over 400 mm of rain in February, when their normal annual rainfall is 200-300 mm. Heavy rain in November caused widespread flooding over central and north-west New South Wales and south-west Queensland affecting one third of New South Wales.

Major droughts affected much of south-eastern Europe, the Middle East, and central Asia through northern China. Especially hard hit were Bulgaria, the Islamic Republic of Iran, Iraq, Afghanistan and parts of China.

This was the worst drought in over 30 years in the Islamic Republic of Iran destroying crops and killing livestock.

In North America, months of above average temperature coincided with below normal precipitation through northern Mexico and much of the southern and western regions of the United States leading to one of the worst wildfire seasons in the past 50 years. Severe to extreme drought covered 36% of the USA by the end of August.

A scorching heat wave gripped much of southern Europe during June and July, breaking many century-old records. The heat wave claimed numerous lives across the region as temperatures exceeded 43°C in locations across Turkey, Greece, Romania and Italy. In Bulgaria, 100-year records for daily maximum temperature were broken at more than 75% of all observation stations on July 5th.

The warm and dry conditions also led to 1,400 wildfires that consumed more than 58,000 hectares destroying 73 homes. Greece also suffered from hundreds of fires during the height of the heat wave. One of the most devastated areas was Samos where fire consumed one-fifth of the island.

The third consecutive year of below normal rainfall in the Horn of Africa countries exacerbated existing drought conditions over much of the area, resulting in severe food shortages. Tens of millions of people were affected by this drought. Especially hard hit were Ethiopia, and parts of Kenya, Somalia, Eritrea and Djibouti. Severe cold conditions affected large parts of China and Mongolia from January through February. Over one million people were affected with economic loss estimated at over 30 million dollars US. In January and February severe cold conditions affected part of India resulting in over 300 deaths.

In May, much of western Russia, centred at the Volga region, experienced a severe cold spell with temperatures 4-5°C below normal. In South America, Paraguay experienced the lowest minimum temperatures ever recorded at nearly all stations during June and July.

April 2000 was the wettest April in the 235-year monthly England and Wales precipitation series. October and November 2000 each had the highest ever daily England and Wales precipitation recorded in that calendar month in a 70-year record.

Sustained above-average rain fall from September through November 2000 led to major flooding in many parts of England and Wales.

It was the wettest autumn in the 235-year record and also the wettest 3-month period on record. June 2000 was the wettest June in 80 years in part of central Chile, in contrast to a significant rainfall deficit that characterized the rest of the wet season.

The first thunderstorm on record moved through Barrow, Alaska, on 20 June 2000. Thunderstorms are more typical of warmer climates. In early November, 692 mm of rain fell at Hilo, Hawaii, in one 24-hour period, breaking the previous 24-hour record of 566 mm.

During the Northern Hemisphere summer, Canada experienced its first deadly tornado in over 14 years and, in a rare incident, a hurricane struck land in Newfoundland.

This preliminary information for 2000 is based on observations up to the end of November from a network of ships, buoys and land-based weather stations.

The data are collected and disseminated on a continuing basis by the National Meteorological and Hydrological Services of the WMO Member countries.

Source: WMO