ENVIRONMENT: 2002 the Planet’s Second Warmest Year

By Gustavo Capdevila Reprint | | Print |

Gustavo Capdevila

GENEVA, Dec 18 2002 (IPS) - This year, which saw an increase in the Earth’s average surface temperature, is the second warmest in the 160 years since instrumental measurements of temperatures have been recorded, reports the World Meteorological Organisation (WMO).

Another notable weather trait of 2002 is the reappearance of the phenomenon known as El Niño, though in a more moderate version than its most recent occurrence, in 1997-1998.

Since 1900, the planet’s average surface temperature has risen 0.6 degrees Celsius, and the temperatures recorded this year, through late November, were a half-degree higher than the annual average from 1961 to 1990.

As a result, 2002 replaced 2001 as being the second hottest year – after 1998 – of the 20th century.

The exceptional readings on thermometers in the last few years are not isolated incidents. "Clearly, for the past 25 or 26 years, the warming has been accelerating," said WMO Climate Programme director Kenneth Davidson, adding that the rate of increase "is unprecedented in the last thousand years."

This warming has been verified through ice core samples, seabed samples and tree ring samples, Davidson explained.

The rate of warming is the most noteworthy aspect of the phenomenon. Davidson admitted that he is surprised at the rate of temperature increases.

"Personally, I would say it isn’t what I expected," he told a press conference as he presented the WMO report Tuesday. "I think that everyone is surprised to see this rate of increase" in the average world temperatures.

The phenomenon is being tracked by the Intergovernmental Panel on Climate Change (IPCC), which is made up of scientists specialising in studying aspects related to global warming.

In its the third assessment report, the IPCC states that the world is warming at unprecedented rates and it is "likely" that human activities are influencing this phenomenon.

"And I would say that certainly is the opinion of the members of the WMO as well," the United Nations agency entrusted with research and information on climate phenomenon, said Davidson.

The warming trend will persist unless additional steps are taken to curb greenhouse gas emissions, which contribute to retaining heat in the Earth’s atmosphere, according to WMO assistant secretary-general Hong Yan.

The WMO annual report, which Yan presented Tuesday in Geneva, notes the reappearance in 2002 of conditions in the tropical Pacific that are known to give rise to El Niño.

The El Niño event occurs every three to seven years, when the sea-surface temperature over a large area of the equatorial Pacific, off Australia, becomes warmer than normal, and this current of warmer water moves eastwards, towards South America.

The presence of the current alters the winds and the climate in general, and can cause weather extremes, including torrential rains and drought, in the Pacific region.

Climatologists explain that El Niño is only one stage of a characteristic cycle of changes that occur in this region, and can be likened to a pendulum. An El Niño event occurs when the pendulum reaches its maximum point.

The two relatively recent El Niño experiences that are considered the most intense in history occurred in 1982-1983 and 1997-1998, causing the extremes of drought and flooding, with devastating consequences for humans and for economies.

But Davidson said, "We are anticipating that the El Niño conditions will begin to move back to neutral after next May."

The WMO also called attention to the reduced size of the so- called ozone hole over Antarctica. The Southern Hemisphere spring is when the atmospheric ozone layer thins, but this year the total area of the hole was the smallest since 1988.

In late September, an unprecedented event occurred: the ozone hole cleaved into two parts. The hole expanded until mid-October, but by early November it had disappeared. The thinning is cyclical, occurring from September to as late as December.

The limited area of the hole and the brevity of its appearance can be explained by meteorological conditions in the stratosphere, says the WMO. Efforts must continue to eliminate the production and use of ozone-depleting gases, particularly CFCs and furans.

The UN agency’s report also states that the extent of sea ice covering the Arctic Ocean in September this year was less than in any previous September since 1978, when satellite observations began to be conducted.

ENVIRONMENT: 2002 the Planet’s Second Warmest Year

By Gustavo Capdevila Reprint | | Print |

Gustavo Capdevila

GENEVA, Dec 18 2002 (IPS) - This year, which saw an increase in the Earth’s average surface temperature, is the second warmest in the 160 years since instrumental measurements of temperatures have been recorded, reports the World Meteorological Organisation (WMO).
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