21 Apr 2022
21 Apr 2022
Status: this preprint is currently under review for the journal TC.

New insights into the decadal variability in glacier volume of an iconic tropical ice-cap explained by the morpho-climatic context, Antisana, (0°29’ S, 78°09’ W)

Ruben Basantes-Serrano1,2, Antoine Rabatel3, Bernard Francou3, Christian Vincent3, Alvaro Soruco4, Thomas Condom3, and Jean Carlo Ruíz3,5 Ruben Basantes-Serrano et al.
  • 1Facultad de Ciencias de La Tierra y Agua, Universidad Regional Amazónica Ikiam, Tena, Ecuador
  • 2CAOS, Observatorio del Clima, Quito, Ecuador
  • 3Univ. Grenoble Alpes, CNRS, IRD, Grenoble INP, Institut des Géosciences de l’Environnement (IGE, UMR 5001), F-38000 Grenoble, France
  • 4Instituto de Investigaciones Geológicas y del Medio Ambiente, Universidad Mayor de San Andrés, La Paz, Bolivia
  • 5Sorbonne Université, UMR 7619 METIS, Case 105, 4 place Jussieu, F-75005 Paris, France

Abstract. We present a comprehensive study of the evolution of the glaciers in the Antisana ice cap (tropical Andes) over the period 1956–2016. Based on geodetic observations of aerial photographs and high-resolution satellite images, we explore the effects of morpho-topographic and climate variables on glacier volumes. Contrasting behavior was observed over the whole period, with two periods of strong mass loss: 1956–1964 and 1979–1997, and two periods with slight mass loss: 1965–1978 and 1997–2016. There was a 42 % reduction in the total surface area of the ice cap. Individually, glacier responses were modulated by morpho-topographic variables (e.g., maximum and median altitude, and surface area), particularly in the case of the small tongues located at low elevations (Glacier 1, 5, and 16) which have been undergoing accelerated disintegration since the 1990s, and will likely disappear in the coming years. Moreover, thanks to the availability of aerial data, a surging event was detected in the Antisana G8 in the 2009–2011 period; such an event is extremely rare in this region and deserves a dedicated study. Despite the effect of the complex topography, glaciers react in agreement with changes in climate forcing, with a stepwise transition towards warmer and alternating wet/dry conditions since the mid-1970s. Long-term decadal variability is consistent with the warm/cold conditions observed in the Pacific Ocean represented by the Southern Oscillation Index.

Ruben Basantes-Serrano et al.

Status: open (until 21 Jun 2022)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse

Ruben Basantes-Serrano et al.

Ruben Basantes-Serrano et al.


Total article views: 233 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
178 48 7 233 19 4 3
  • HTML: 178
  • PDF: 48
  • XML: 7
  • Total: 233
  • Supplement: 19
  • BibTeX: 4
  • EndNote: 3
Views and downloads (calculated since 21 Apr 2022)
Cumulative views and downloads (calculated since 21 Apr 2022)

Viewed (geographical distribution)

Total article views: 217 (including HTML, PDF, and XML) Thereof 217 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
Latest update: 24 May 2022
Short summary
We assessed the volume variation of 17 glaciers on the Antisana ice cap, near the equator. We used aerial and satellite images for the period 1956–2016. We highlight very negative changes in 1956–1964 and 1979–1997, and slightly negative or even positive conditions in 1965–1978 and 1997–2016, the latter despite the recent increase in temperatures. Glaciers react according to regional climate variability, while local humidity and topography give specific behavior to each glacier.