Un análisis comparativo del comportamiento diferencial de los glaciares en los Andes Tropicales usando teledetección

Abstract

In this research paper, we analysed the behaviour of Tropical Andean glaciers in a changing climate. We used multi-source satellite images as well as meteorological datasets to achieve this objective. Representative glaciers in four different climatic zones, namely the inner tropics, northern wet outer tropics, southern wet outer tropics and dry outer tropics, were considered in this study. Changes in annual maximum snowline during 1985 -2015 and also the decadal changes in the area between 1975 and 2015 of these glaciers were calculated. Furthermore, we analysed the rate of glacier retreat during the occurrence of El Niño-Southern Oscillation and Pacific Decadal Oscillation. It is observed that the glaciers in both the inner and outer tropics underwent retreat during the study period and most of this retreat occurred during 1975 -1997 which is parallel with the so-called Pacific shift. Exceptional variations in snowline altitude were observed when an El Niño event occurs during the warm phase of the Pacific Decadal Oscillation. No significant signals of the recent hiatus in global warming were observed, except in the dry outer tropics which are situated near the subtropical region.

Mapping Three Decades of Changes in the Tropical Andean Glaciers Using Landsat Data Processed in the Earth Engine

“…Northern Wet Outer Tropics, Southern Wet Outer Tropics, Dry Outer Tropics, and Inner Tropics (Figure 1). [39] and their climatic classification based on Sagredo and Lowell [27,40,41].…”

“…In recent years, the availability, accessibility, and temporal and spatial continuity of satellite data (such as Landsat and Sentinel) [25][26][27][28] and the development of cloud computing platforms, such as Google Earth Engine (GEE) [29], have created an opportunity to map the historical evolution of land cover change, such as water bodies and glaciers [16,18,21,26,[30][31][32][33][34][35][36]. Despite the progress made in recent years in the assessment of glacier areas, there are still many cases in which the automatic delimitation of glacier boundaries in satellite images is complex, error prone, or time consuming [13,20,37].…”

Regional climate forcing and topographic influence on glacier shrinkage: eastern cordilleras of Peru

“…Tropical glaciers in the Andes, particularly in the eastern cordilleras of Peru and Bolivia, were extensively studied in recent years due to their functionality as climate proxies (Vuille et al, 2008a(Vuille et al, , 2008bVeettil et al, 2016aVeettil et al, , 2016b and freshwater resource during dry season (Soruco et al, 2015). Based on the recent Randolph Glacier Inventory (RGI version 5.0), more than 99% of the tropical glaciers of the world are situated in the Andes and nearly 70% of the tropical Andean glaciers are in Peru (Pfeffer et al, 2014), distributed in 20 distinct glacierized mountain ranges (cordilleras) (Morales-Arnao, 1998).…”

Spatio-Temporal Description of the NDVI (MODIS) of the Ecuadorian Tussock Grasses and Its Link with the Hydrometeorological Variables and Global Climatic Indices

“…Various studies on the Andes have confirmed that climatic variables are directly or indirectly linked to global indices [74,[110][111][112][113][114][115][116][117][118][119]. The study correlated greenness with various global climate indices, among which the North Atlantic Oscillation (NAO) had the highest Pearson coefficients.…”

“…NDVI is an indicator of vegetation response that has been used in multiple ecosystem studies [44,[72][73][74][75]. NDVI is sensitive to chlorophyll in leaves and is calculated in terms of reflectance at red and near-infrared wavelengths, according to Equation (1) [13].…”