Karakoram glaciers may lose mass: research study
A new study, exploring the famous `Karakoram Anomaly', did not support the notion that claims stability or anomalous growth of glaciers in the central Karakoram region, and indicated that in contrast to the predictions made in previous studies, temperature increased during the last decade, causing loss of glacial mass and more flooding in future.
Titled as `Climate Change and spatio-temporal trend analysis of climate extremes in the homogeneous climatic zones of Pakistan during 1962-2019', the study is conducted under the Asia Pacific Network for Global Change Research (APN) project and is published in PLos One, an inclusive journal that receives submissions from 207 countries and published 200,000 research based articles since 2004. "The findings indicates that in contrast to previous studies in the Karakoram region, temperature has increased in the last decade, providing an updated, indirect status of the Karakoram anomaly," shares Dr Shaukat Ali, a PhD scholar on Meteorology and head of APN project who led the research study.
The study is authored by Firdos Khan from NUST institute while other scholars are Christoph Mayer, a German Scientist on Glacier Studies, Hamdullah and Sher Muhammad of ICIMOD. "The Karakoram glaciers may no longer be stable and lose mass in the future due to increase in temperature," warns Dr Shaukat Ali. "Karakoram Anomaly is a notion made by some scientists that in contrast to the retreat of glaciers in nearby mountainous ranges of Himalayas and other in the world, the Karakoram glaciers are stable and growing," Shaukat explains.
From 1960 to 1990, there was slide decrease in temperature in the Karakoram region, but in last ten years the trend changed in the region. The latest findings suggested that the glacier may lose mass in future; rather than gaining or stable conditions and there will be more flooding in the country, he added. In the Karakoram region, temperature decreased significantly also precipitation increased significantly in this region except a significant decrease in Gilgit. However, precipitation and temperature have increasing trend during the most recent period (2010-2019), which do not support the notion of Karakoram Anomaly.
The objective of the study is to investigate the changes in climate and climate extremes by considering two time slices (i.e., 1962-1990 and 1991-2019) in all climate zones of Pakistan by utilizing observed data from 54 meteorological stations. Different statistical methods and techniques were applied on observed station data to assess changes in temperature, precipitation and spatio-temporal trends of climatic extremes over Pakistan from 1962 to 2019. The Mann-Kendal test demonstrated increasing precipitation (DJF) and decreasing maximum and minimum temperatures (JJA) at the meteorological stations located in the Karakoram region during 1962-1990.
The decadal analysis, on the other hand, showed a decrease in precipitation during 1991-2019 and an increase in temperature (maximum and minimum) during 2010-2019, which is consistent with the recently observed slight mass loss of glaciers related to the Karakoram Anomaly. The target location of the study was divided in five zones of which zone one was cold regions including northern and central-western parts of the country. Zone 2 comprised of Islamabad Capital Territory (ICT), some parts of AzadJammu and Kashmir and Khyber Pakhtunkhwa which is part of the monsoon dominated region and receive maximum rainfall during the monsoon season. Zone 3 is the south-western part of the country and has least rainfall in a year as compared to the other regions of the country.
Zone 4 includes the southeastern and coastal areas in the south of the country. While Zone 5 is the centraleastern part of the country and due to its fertile land, it is considering the food basket of the country. The researchers observed daily climate data (maximum, minimum temperature and precipitation) for the period of 1962-2019 acquired from the Pakistan Meteorological Department (PMD) for 54 meteorological stations across the country.
The spatial distribution of meteorological stations' data was divided into two independent climatic periods (1962-1990 and 1991-2019) for the assessment of climate change and extremes analysis over Pakistan. Climate extremes related to temperature and precipitation were calculated for both time slices. To assess the changes in climate extremes, probability density functions were drawn and a comparison is made between them, Dr Shaukat notes.