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More lakes in the Himalayas

Baltoro Glacier in northern Pakistan: thermometer of climate change

Guilhem Vellut / Wikicommons Baltoro Glacier in northern Pakistan: thermometer of climate changeGuilhem Vellut / Wikicommons

A research group led by glaciologist Jefferson Simões, a researcher at the Climatic and Polar Research Center at the Federal University of Rio Grande do Sul (UFRGS), went far and wide (remotely, at least) in search of the effects of global climate change. Using satellite images captured between 1978 and 2014, the group mapped the lakes in the Baltoro Glacier of the Karakoram range, a part of the Himalayas in northern Pakistan. The group recorded a gradual increase in the number and area of the lakes until 2008, according to an article to be published in January 2016 in the journal Geocarto International, already available online. The first author of the report is Bijeesh Veettil, a doctoral student from India at the Climatic and Polar Research Center at UFRGS. The glaciers in the studied area, located roughly 3,500 meters above sea level, are covered with pebbles and sand instead of the smooth ice that one would normally imagine. This coverage decreases the frequency of lake formation, which only happens when there is a significant increase in thawing, therefore making it an indicator of increased air temperature. The area of the lakes diminished slightly in recent years, a fact that the UFRGS researchers are trying to explain. This trend inversion seems to be related to a change of phase in the phenomenon known as the Pacific Decadal Oscillation (PDO), which affects temperatures mainly in the northern Pacific Ocean. The Himalayan lakes expanded during the warm phase of the PDO, especially in the period coinciding with the effects of El Niño. The study suggests a need for further study into how Asian glaciers are affected by the PDO, whose effects are similar to El Niño, but last a few decades.  Having more complete results could bring important insights into global climate change.