Abstract
The equilibrium-line altitude (ELA) marks the area or zone on a glacier where accumulation is balanced by ablation over one year. The ELA is sensitive to several meteorological factors, such as variations in winter precipitation, summer temperature, and wind transport of dry snow. When the annual net mass balance is negative, the ELA rises, and when the annual net mass balance is positive, the ELA falls. Fluctuations in the ELA provide an important indicator of glacier response to climate change that allows paleoclimate reconstructions (accumulation-season precipitation, ablation-season temperature, and prevailing snow-bearing wind directions). Paleoclimatic reconstructions based on former glacier extent commonly include estimates of equilibrium-line altitudes (ELAs) and depression of ELAs from present values. A variety of methods have been developed to estimate steady-state ELAs of former glaciers as a tool for reconstructing paleoclimates in glaciated regions. These include the maximum elevation of lateral moraines (MELM), the median elevation of a glacier (MEG), the toe-to-headwall altitude ratio (THAR), the toe-to-summit altitude method (TSAM), the accumulation area ratio to the total glacier area (AAR), the balance ratio (BR) method, cirque floor altitudes and proglacial depositional archives.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Reference Module in Earth Systems and Environmental Sciences
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
