Glacier regression in the tropical Andes has accelerated considerably over the past 30 years. This change is cause for great concern, insofar as many regions of the Andes depend on the Cordillera’s glaciers for their water supply (2).
In 1991 scientists from the IRD research unit Great Ice (UR032) set up an observation network, jointly with their Bolivian, Peruvian and Ecuadorian partners. This system takes in a dozen glaciers along the Andes between the Equator and longitude 16°S (Bolivia). In contrast to the Alpine glaciers which undergo a long accumulation period in winter and a short ablation season in summer, the glaciers of the tropical Andes experience an ablation regime in their lower part throughout the year, with a maximum during the Southern summer (October to April) in Bolivia and Peru. That is the season when the strongest insolation coincides with the maximum rainfall. The glaciers, which react strongly to oscillations in these two parameters and are therefore highly sensitive indicators of climate changes. The scientists focused on two representative glaciers from among those scattered over the Cordillera: Antizana (5760-4800 m) in Ecuador and Chacaltaya (5375-5125 m) in the North of Bolivia.
The glacier mass balance, which is an estimate of the difference between the accumulation of snow and ice and their ablation by melting and sublimation, appears to be strongly controlled by the ENSO (El Niño-Southern Oscillation). During the latter’s warm phases (El Niño), the balances are always negative. In the course of a year, the glaciers lose the equivalent of a sheet of water of 600 to 1200 mm. In the cooler and more humid La Niña phase, however, the glaciers return to equilibrium and sometimes show a small increase which temporarily checks their decline.
Marie Guillaume | alfa
New Study Will Help Find the Best Locations for Thermal Power Stations in Iceland
19.01.2017 | University of Gothenburg
Water - as the underlying driver of the Earth’s carbon cycle
17.01.2017 | Max-Planck-Institut für Biogeochemie
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
20.01.2017 | Awards Funding
20.01.2017 | Materials Sciences
20.01.2017 | Life Sciences