Posts Tagged "tibetan plateau"

Roundup: Hindu Kush glaciers, Tibetan lakes and science vs. politics in Chile

Posted by on Feb 16, 2015 in All Posts, Featured Posts, Images, Roundup, Science | 1 comment

Roundup: Hindu Kush glaciers, Tibetan lakes and science vs. politics in Chile

Spread the News:ShareGlacier changes in Hindu Kush Himalayas                  “The fate of the Hindu Kush Himalayan glaciers has been a topic of heated debate due to their rapid melting and retreat. The underlying reason for the debate is the lack of systematic large-scale observations of the extent of glaciers in the region owing to the high altitude, remoteness of the terrain, and extreme climatic conditions. Here we present a remote sensing–based comprehensive assessment of the current status and observed changes in the glacier extent of the Hindu Kush Himalayas. It reveals highly heterogeneous, yet undeniable impacts of climate change.” Read more of this article here.   Lakes and glaciers in Tibetan Plateau               “Levels and surface areas of lakes are indicators of climate change and climate variability. Information of the surface extent of all the lakes on the northeastern Tibetan Plateau and its adjacent areas was extracted from Landsat images obtained in the 1970s, the 1990s, around 2000, and 2010 and developed a lake spatial database. The dynamic changes of the number and lake surface area in the past forty years were analyzed. ” Read more about the changes of the lakes and glaciers in Tibetan Plateau here.   Science vs. politics in Chile                   “Chile’s scientific community fractured over how to define credible science. Divisive and decisive issues included the source of funding, ethics, access to resources, and being local. Although some scientists and non-scientists used boundary work to try to affirm the authority of science, no stable map of scientific credibility resulted from these efforts. Chile’s new democracy is more plural than its recent military dictatorship but still lacks adequate spaces in which to negotiate what counts as credible science. These experiences highlight the need to better understand how science fares through regime transitions and what it contributes to emerging democracies.” Read more about this article here. Spread the...

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On Tibetan Plateau, Permafrost Melt Worse Than Glacial Melt

Posted by on Jan 14, 2015 in Adaptation, All Posts, Featured Posts, Science | 0 comments

On Tibetan Plateau, Permafrost Melt Worse Than Glacial Melt

Spread the News:ShareAccording to a recent study published in the journal Public Library of Science, glacial melt is taking a backseat in the Himalayas to permafrost melt as a central driver of alpine lake expansion and related environmental hazards. This finding is of great importance to policy-makers and communities, who must prepare for flooding and other hazards which can be caused by the expansion of high-altitude lakes. The study, led by Yingkyui Li of the University of Tennessee, Knoxville in partnership with the Chinese Academy of Sciences, Beijing, determined that patterns of lake changes in the Tibetan Plateau from 1970 to 2010 were more closely associated with changes in permafrost degradation patterns than glacial retreat patterns. This conclusion suggests, at least for this region, the influence of melting glaciers on lake dynamics is outweighed by other environmental processes. Permafrost is an ecologically important element of high-latitude and high-altitude ecosystems. Permafrost is defined as “perennially frozen ground remaining at or below 0°C for at least two consecutive years,” according to a document on the policy implications of warming permafrost, released by UNEP (United Nations Environment Programme). This frozen soil comprises about 24 percent of the exposed land area in the Northern Hemisphere, and is also found in mountainous regions of South America and ice-free regions of Antarctica. The thickness of permafrost is determined by the distance between the top of the permafrost layer, known as the permafrost table, and the bottom, also called the permafrost base. There may be an active layer above this, which thaws and freezes seasonally. The most robust type of permafrost is continuous coverage, where the permafrost table is very thick and extends for many meters into the soil. Areas with larger gaps in the permafrost can be called discontinuous permafrost zones, or sporadic permafrost.   At the outset of the study, researchers did not hypothesize that permafrost would play an active role in Tibetan Plateau lake dynamics. In order to determine the factors which influenced lakes, Li et al. gathered two sorts of data to assess fluctuations in the elevation of lakes. They used historical altimetry data for 94 lakes across the plateau for 2003-2009, and Landsat imagery data for 25 lakes across five different regions in the plateau for1972-2010. They correlated spatio-temporal patterns of lake change with various climate and environmental variables such as precipitation, evapotranspiration, glacier coverage, permafrost coverage, and daily mean temperature trends.   The analysis revealed clear spatio-temporal patterns. Lakes in the southern and western plateau showed continuous shrinkage or stable levels except for slight expansion from 2000-2004. Lakes closest to the Himalayas showed evidence of continuous shrinkage. Lakes located in the central and northern plateau seemed to experience rapid expansion after 2000, though data showed slowed expansion after 2006 in the central region. These expansion trends have been confirmed by other studies, including an article published in April 2014; however, the study led by Yingkyui Li is unique in its long time scale and fine-grained analysis of spatio-temporal patterns. The researchers found, “[there is] no statistically significant correlation between changes in lake levels (2003-2009) and glacier coverage in each lake’s drainage basin.” On the other hand, they were able to conclude, “[the] plateau-wide pattern of lake changes is consistent with the distribution of permafrost on the Tibetan Plateau.” The mechanism that links permafrost melt with lake expansion rests on temperature regimes in the region. When the ground temperature is lower than the melting point of frozen soil, water contribution of permafrost to lakes is limited because the soil remains frozen. However, higher temperatures accelerate permafrost melt, which contributes to lake expansion. An...

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Climate change worsens gender inequality in the Himalayas

Posted by on Sep 24, 2014 in All Posts, Communities, Featured Posts | 1 comment

Climate change worsens gender inequality in the Himalayas

Spread the News:ShareIn the Himalayas, when a flash flood rips through a village or when a glacial lake flood outburst wipes one out entirely, surviving families relocate to new settlements, where women are often burdened with more labor and kept away from school, or sent off to an early marriage. Climate impacts have made gender and ethnic inequality more acute in terms of access to education, health care and food security. Men have more opportunities for wage labor and better access to government services. Some women can obtain resources for themselves and for their children through the men they have ties to, but that dependence can leave them in an unfavorable position. Other women are left with little or no possibility of mobilizing ties to men to obtain resources. At the People’s Climate March on Sunday, the Himalayan women of New York marched in solidarity with women who are affected by climate change. Himalayan communities from the Tibetan Plateau to the South Asian plains have firsthand experience of the adverse impact of climate change, including flash floods, reduced water access and erratic weather patterns. ACHA Himalayan Sisterhood, an emerging international network of Himalayan women working towards women empowering women in creating safe, supportive space for all, presented demands for climate justice. The Himalayan women called for immediate expansion of resources to build climate resilience through domestic and international policies that rest on local control of land and other resources. Women are at the center of climate change impact as they are disproportionally impacted. In mountain communities and rural villages around the world, women are the ones who collect water, firewood and other resources to feed families. This August, torrential rainfall in Nepal led to flash floods and mudslides which claimed more than 180 lives and displaced hundreds of thousands. Events such as this recur often, and are becoming more frequent as climate change progresses. Spread the...

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