Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Unprecedented glacier melting in the Andes blamed on climate change

22.01.2013
Glaciers in the tropical Andes have been retreating at increasing rate since the 1970s, scientists write in the most comprehensive review to date of Andean glacier observations.
The researchers blame the melting on rising temperatures as the region has warmed about 0.7°C over the past 50 years (1950-1994). This unprecedented retreat could affect water supply to Andean populations in the near future. These conclusions are published today in The Cryosphere, an Open Access journal of the European Geosciences Union (EGU).

The international team of scientists – uniting researchers from Europe, South America and the US – shows in the new paper that, since the 1970s, glaciers in tropical Andes have been melting at a rate unprecedented in the past 300 years. Globally, glaciers have been retreating at a moderate pace as the planet warmed after the peak of the Little Ice Age, a cold period lasting from the 16th to the mid-19th century. Over the past few decades, however, the rate of melting has increased steeply in the tropical Andes. Glaciers in the mountain range have shrunk by an average of 30-50% since the 1970s, according to Antoine Rabatel, researcher at the Laboratory for Glaciology and Environmental Geophysics in Grenoble, France, and lead author of the study.

Glaciers are retreating everywhere in the tropical Andes, but the melting is more pronounced for small glaciers at low altitudes, the authors report. Glaciers at altitudes below 5,400 metres have lost about 1.35 metres in ice thickness (an average of 1.2 metres of water equivalent [see note]) per year since the late 1970s, twice the rate of the larger, high-altitude glaciers.
“Because the maximum thickness of these small, low-altitude glaciers rarely exceeds 40 metres, with such an annual loss they will probably completely disappear within the coming decades,” says Rabatel.

The researchers further report that the amount of rainfall in the region did not change much over the past few decades and, therefore, cannot account for changes in glacier retreat. Instead, climate change is to blame for the melting: regional temperatures increased an average of 0.15°C per decade over the 1950-1994 period.

“Our study is important in the run-up to the next IPCC report, coming out in 2013,” says Rabatel. The Intergovernmental Panel on Climate Change (IPCC) has pointed out that tropical glaciers are key indicators of recent climate change as they are particularly sensitive to temperature changes. The tropical Andes host 99% of all tropical glaciers in the world, most of them in Peru.

The research is also important to anticipate the future behaviour of Andean glaciers and the impact of their accelerated melting on the region. “The ongoing recession of Andean glaciers will become increasingly problematic for regions depending on water resources supplied by glacierised mountain catchments, particularly in Peru,” the scientists write. Without changes in precipitation, the region could face water shortages in the future.
The Santa River valley in Peru will be most affected, as its hundreds of thousands of inhabitants heavily rely on glacier water for agriculture, domestic consumption, and hydropower. Large cities, such as La Paz in Bolivia, could also face shortages. “Glaciers provide about 15% of the La Paz water supply throughout the year, increasing to about 27% during the dry season,” says Alvaro Soruco, a Bolivian researcher who took part in the study.

In their comprehensive review of Andean glaciers, the scientists synthesised data collected over several decades, some dating as far back as the 1940s. “The methods we used to monitor glacier changes in this region include field observations of glacier mass balance, and remote-sensing measurements based on aerial photographs and satellite images for glacier surface and volume changes,” explains Rabatel.
The study takes into account data collected for glaciers in Colombia, Ecuador, Peru and Bolivia, covering a total of almost a thousand square kilometres. This corresponds to about 50% of the total area covered by glaciers in the tropical Andes in the early 2000s.

The research was conducted to provide the scientific community with a comprehensive overview of the status of glaciers in the tropical Andes and determine the rate of retreat and identify potential causes for the melting. But the authors hope the results can have a wider impact.

“This study has been conducted with scientific motivations, but if the insight it provides can motivate political decisions to mitigate anthropogenic impact on climate and glacier retreat, it will be an important step forward,” Rabatel concludes.

*Note*
Glacier mass balance is the difference between ice accumulation and ablation (melting and sublimation) in a glacier. Scientists express the annual mass balance in metre water equivalent (m w.e.). A loss of 1.2 m w.e. corresponds to a reduction of about 1.35 metres in ice thickness.
*More information*
This research is presented in the paper ‘Current state of glaciers in the tropical Andes: a multi-century perspective on glacier evolution and climate change’ to appear in the EGU Open Access journal The Cryosphere on 22 January 2013.

The peer-reviewed scientific article is available online, from the publication date onwards, at http://www.the-cryosphere.net/recent_papers.html. Please contact the EGU Media and Communications Officer if you would like the final version of the paper before the publication date.

The discussion paper (before peer review) and reviewers comments is available at

http://www.the-cryosphere-discuss.net/6/2477/2012/tcd-6-2477-2012-discussion.html

The team is composed of A. Rabatel (Laboratory of Glaciology and Geophysics of the Environment [LGGE], Joseph Fourier University, Grenoble, France), B. Francou (Laboratory for the Study of Transfers in Hydrology and Environment [LTHE], Joseph Fourier University, Grenoble, France), A. Soruco (Institute of Geological and Environmental Research, Universidad Mayor de San Andres [IGEMA-UMSA], La Paz, Bolivia), J. Gomez (National Water Authority, Glaciology and Water Resources Unit [ANA-UGRH], Huaraz, Peru), B. Cáceres (National Institute of Meteorology and Hydrology [INAMHI], Quito, Ecuador), J. L. Ceballos (Institute of Hydrology, Meteorology and Environmental Studies [IDEAM], Bogotá, Colombia), R. Basantes (LTHE -and- Department of Civil and Environmental Engineering, National Politechnic School [DICA-EPN], Quito, Ecuador), M. Vuille (Department of Atmospheric and Environmental Sciencies, University of Albany, New York, USA), J.-E. Sicart (LTHE), C. Huggel and M. Scheel (Department of Geography, University of Zurich, Switzerland), Y. Lejeune (Snow Research Centre, National Centre for Meteorological Research (CEN CNRM-GAME), Saint Martin d'Hères, France), Y. Arnaud (LTHE), M. Collet (LTHE -and- DICA-EPN), T. Condom (LTHE), G. Consoli (LTHE), V. Favier (LGGE), V. Jomelli (Laboratory of Physical Geography (LPG), University of Paris-Sud, Paris, France), R. Galarraga (DICA-EPN), P. Ginot (LGGE -and- Grenoble Observatory for the Sciences of the Universe (OSUG), Grenoble, France), L. Maisincho (INAMHI), J. Mendoza (Institute of Hydraulics and Hydrology, UMSA [IHH-UMSA], La Paz, Bolivia), M. Ménégoz (LGGE), E. Ramirez (IHH-UMSA), P. Ribstein (Sisyphe, University Pierre and Marie Curie, Paris, France), W. Suarez (National Service of Meteorology and Hydrology (SENAMHI), Lima, Peru), M. Villacis (DICA-EPN), and P. Wagnon (LTHE). Most of these researchers are members of the International Joint Laboratory GREAT-ICE, an initiative of the French Institute of Research for Development (IRD) and universities and institutions in Bolivia, Peru, Ecuador, and Colombia.

The European Geosciences Union (www.egu.eu) is Europe’s premier geosciences union, dedicated to the pursuit of excellence in the Earth, planetary, and space sciences for the benefit of humanity, worldwide. It is a non-profit interdisciplinary learned association of scientists founded in 2002. The EGU has a current portfolio of 14 diverse scientific journals, which use an innovative open-access format, and organises a number of topical meetings, and education and outreach activities. Its annual General Assembly is the largest and most prominent European geosciences event, attracting over 10,000 scientists from all over the world. The meeting’s sessions cover a wide range of topics, including volcanology, planetary exploration, the Earth’s internal structure and atmosphere, climate, energy, and resources. The 2013 EGU General Assembly is taking place is Vienna, Austria from 7-12 April. For information regarding the press centre at the meeting and media registration, please check http://media.egu.eu.

Contacts
Antoine Rabatel
Laboratory for Glaciology and Environmental Geophysics
Grenoble, France
Tel: +33-4-7682-4271
Email: rabatel@lgge.obs.ujf-grenoble.fr

Bárbara Ferreira
EGU Media and Communications Officer
Munich, Germany
Tel: +49-89-2180-6703
Email: media@egu.eu

Dr. Bárbara Ferreira | European Geosciences Union (EGU)
Further information:
http://www.egu.eu
http://www.egu.eu/news/55/unprecedented-glacier-melting-in-the-andes-blamed-on-climate-change/

More articles from Earth Sciences:

nachricht In times of climate change: What a lake’s colour can tell about its condition
21.09.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)

nachricht Did marine sponges trigger the ‘Cambrian explosion’ through ‘ecosystem engineering’?
21.09.2017 | Helmholtz-Zentrum Potsdam - Deutsches GeoForschungsZentrum GFZ

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

Im Focus: Fast, convenient & standardized: New lab innovation for automated tissue engineering & drug

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Comet or asteroid? Hubble discovers that a unique object is a binary

21.09.2017 | Physics and Astronomy

Cnidarians remotely control bacteria

21.09.2017 | Life Sciences

Monitoring the heart's mitochondria to predict cardiac arrest?

21.09.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>