Equatorial Alpine Glaciers as a Mars Analog: A Preliminary Assessment
Abstract
Most terrestrial analogs for modern/Amazonian Mars are found in the coldest polar regions of Earth, especially the Antarctic Dry Valleys. However, the habitability of these regions is largely controlled by seasonal melting cycles that are a poor analog for Mars. To help minimize these seasonal effects, we propose that high-elevation regions nearer the equator may be a better analog for Mars in this regard. We are conducting a study of two stratovolcanoes within the Cordillera Neovolcánica mountain range in central Mexico: Pico de Orizaba [19.03°N, 97.27°W] and Iztaccíhuatl [19.18°N, 98.64°W]. Both peaks possess summit glaciers and are thought to have annual temperatures that rarely exceed 0°C, although no long-term in situ climate monitoring has been conducted. While glacial losses have been observed in recent history using remote sensing data, we hypothesize that, due to the persistently low temperatures, this loss may be more largely driven by sublimation processes.
We measure the glacial extents in both regions using multispectral imagery from the Landsat 7-8 and Sentinel-2 orbiters. Glacial mapping is performed via semi-automated methods, using the ratio of the red and short wave infrared bands. Appropriate threshold value are identified for each scene and used to generate glacier outlines that are manually corrected as needed. Preliminary mapping indicates that the present-day extents of the glaciers at Pico de Orizaba and Iztaccíhuatl are 0.99 and 0.23 km2, respectively. To determine the temporal history of ice loss, older imagery will be mapped to identify regions within the summit area that have been deglaciated. We will also estimate the variation in the surface temperature of both the glaciers and the surrounding summit regions over annual and decadal timescales using thermal data to look for correlations with ice loss. Longer-term goals include (1) the establishment of ground stations to monitor climatic parameters in situ and help determine the relative influence of sublimation on ice loss and (2) the exploration of the microbial ecology within the glaciers and the surrounding regions to better understand the habitability of these environments. Through these tasks, we will begin to assess the equatorial alpine as a potential Mars analog environment.- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFM.P31H3792V
- Keywords:
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- 5464 Remote sensing;
- PLANETARY SCIENCES: SOLID SURFACE PLANETSDE: 5470 Surface materials and properties;
- PLANETARY SCIENCES: SOLID SURFACE PLANETSDE: 5494 Instruments and techniques;
- PLANETARY SCIENCES: SOLID SURFACE PLANETSDE: 5499 General or miscellaneous;
- PLANETARY SCIENCES: SOLID SURFACE PLANETS