Worldwide glacier melt continues to rise

Posted: 29 January 2007

Mountain glaciers around the world continue to melt, with new, still tentative figures for 2005 indicating a further average loss in thickness by a set of reference glaciers over the past two and a half decades amounting to 9.6 metres.

The still tentative data for 2005 show that these 30 glaciers lost 0.6 metre water equivalent (w.e.)in that year. (On average, one metre water equivalent corresponds to 1.1 metre ice thickness.)

This confirms the trend in accelerated ice loss during the past 25 years and brings the average thickness loss since 1980 of the 30 reference glaciers of nine mountain ranges at about 9.6 metre w.e. These results come from glacier mass balance measurements collected by scientistsall over the world and published by the World Glacier Monitoring Service (WGMS) in Zurich, Switzerland.

The preliminary data on glacier change for the year 2005 from 80 glaciers was reported to the WGMS from the majority of the glaciated mountain ranges of the world. Thirty of these glaciers have continuous mass balance measurement series since 1980. Their average annual ice loss since the year 2000 was about 0.6 metre w.e., which is 1.6 times more than the average of the 1990s and three times the loss rate of the 1980s.

Comprehensive data for the year 2006 are not yet available, but as it was one of the warmest years in many parts of the world, it is expected that the downward trend will continue.

Rivers threatened

Achim Steiner, UN Under-Secretary General and UNEP Executive Director, said:"This is the most authoritative, comprehensive and up-to-dateinformation on glaciers world-wide and as such underlines the rapid changes occurring on the planet as a result of climate change. Glaciers across the globe are important sources of water for many important rivers - rivers upon which people depend for drinking water, agriculture and industrial purposes".

"The findings confirm the science of human-induced climate change, confirmation that will be further underlined when the IntergovernmentalPanel on Climate Change unveil their next report on 2 February.

These findings should strengthen the resolve of governments to act now to reduce greenhouse gas emissions and put in place the medium to longer term strategies necessary to avert dangerous climate change," he added

Michael Zemp, a glaciologist and research associate at the WGMS said: "Today, the glacier surface is much smaller than in the 1980s, this means that the climatic forcing has continued since then. The recent increase in rates of ice loss over reducing glacier surface areas leaves no doubt about the accelerated change in climatic conditions", he said.

The WGMS collects and publishes standardised glacier data which are considered to be among the best natural indicators of climate change.Scientific measurements relate to the so-called 'net mass balance' of glaciers, which can be seen as their overall ice thickness change. The long-term monitoring of glacier mass balance produces one of the most essential variables required for the regular assessment reports on global climate monitoring. As such, the glacier mass balance data are an important contribution to UNEP's Global Environment Outlook (GEO) report and one of the headline indicators presented in the GEO Yearbook series.

The new preliminary findings also underlines the importance of this year's 5 June World Environment Day theme Melting Ice- A Hot Topic? . The main international celebrations, which also coincide with International PolarYear, will be held in Norway.

Related links:

World Glacier Monitoring Service

UNEP GEO Data Portal

World Environment Day 2007

Source: UNEP 30 January 2007