Browsing by Autor "Christian Huggel"

Now showing 1 - 4 of 4

Current state of glaciers in the tropical Andes: a multi-century perspective on glacier evolution and climate change
(Copernicus Publications, 2013) Antoine Rabatel; Bernard Francou; Álvaro Soruco; Jesús Gómez; Bolívar Cáceres; J. L. Ceballos; Rubén Basantes-Serrano; Mathias Vuille; Jean‐Emmanuel Sicart; Christian Huggel
Abstract. The aim of this paper is to provide the community with a comprehensive overview of the studies of glaciers in the tropical Andes conducted in recent decades leading to the current status of the glaciers in the context of climate change. In terms of changes in surface area and length, we show that the glacier retreat in the tropical Andes over the last three decades is unprecedented since the maximum extension of the Little Ice Age (LIA, mid-17th–early 18th century). In terms of changes in mass balance, although there have been some sporadic gains on several glaciers, we show that the trend has been quite negative over the past 50 yr, with a mean mass balance deficit for glaciers in the tropical Andes that is slightly more negative than the one computed on a global scale. A break point in the trend appeared in the late 1970s with mean annual mass balance per year decreasing from −0.2 m w.e. in the period 1964–1975 to −0.76 m w.e. in the period 1976–2010. In addition, even if glaciers are currently retreating everywhere in the tropical Andes, it should be noted that this is much more pronounced on small glaciers at low altitudes that do not have a permanent accumulation zone, and which could disappear in the coming years/decades. Monthly mass balance measurements performed in Bolivia, Ecuador and Colombia show that variability of the surface temperature of the Pacific Ocean is the main factor governing variability of the mass balance at the decadal timescale. Precipitation did not display a significant trend in the tropical Andes in the 20th century, and consequently cannot explain the glacier recession. On the other hand, temperature increased at a significant rate of 0.10 °C decade−1 in the last 70 yr. The higher frequency of El Niño events and changes in its spatial and temporal occurrence since the late 1970s together with a warming troposphere over the tropical Andes may thus explain much of the recent dramatic shrinkage of glaciers in this part of the world.
Making Connections for Our Changing Mountains: Future Directions for the Mountain Research Initiative (MRI)
(International Mountain Society, 2020) Carolina Adler; Jörg Balsiger; Adrienne Grêt‐Regamey; Andreas Heinimann; Christian Huggel; Rolf Weingartner; Irasema Alcántara-Ayala; Aster Gebrekirstos; Ricardo Grau; Elizabeth Jiménez
The Mountain Research Initiative (MRI) promotes basic and applied research to understand how drivers and processes of global change present challenges and opportunities in mountain social-ecological systems. It convenes a global network that collectively generates and synthesizes knowledge on global change in mountains that also supports decisions and actions to enable sustainable development. Building on the considerable social and intellectual wealth fostered by the MRI over its past 20-plus years of existence, we outline future directions aimed at supporting and further developing the network as well as our flagship and community-led activities aimed at linking and scaling interdisciplinary and transdisciplinary research efforts within and across mountain regions worldwide.
Rapid decline of snow and ice in the tropical Andes – Impacts, uncertainties and challenges ahead
(Elsevier BV, 2017) Mathias Vuille; Mark Carey; Christian Huggel; Wouter Buytaert; Antoine Rabatel; Dean Jacobsen; Álvaro Soruco; Marcos Villacís; Christian Yarlequé; O. Elison Timm
Review article of the current state of glaciers in the tropical Andes: a multi-century perspective on glacier evolution and climate change
(2012) Antoine Rabatel; Bernard Francou; Álvaro Soruco; Jesús Gómez; Bolívar Cáceres; J. L. Ceballos; Rubén Basantes-Serrano; Mathias Vuille; Jean‐Emmanuel Sicart; Christian Huggel
Abstract. The aim of this paper is to provide the community with a comprehensive overview of the studies of glaciers in the tropical Andes conducted in recent decades leading to the current status of the glaciers in the context of climate change. In terms of changes in surface area and length, we show that the glacier retreat in the tropical Andes over the last three decades is unprecedented since the maximum extension of the LIA (mid 17th–early 18th century). In terms of changes in mass balance, although there have been some sporadic gains on several glaciers, we show that the trend has been quite negative over the past 50 yr, with a mean mass balance deficit for glaciers in the tropical Andes that is slightly more negative than the computed global average. A break point in the trend appeared in the late 1970s with mean annual mass balance per year decreasing from −0.2 m w.e. in the period 1964–1975 to −0.76 m w.e. in the period 1976–2010. In addition, even if glaciers are currently retreating everywhere in the tropical Andes, it should be noted that as a percentage, this is much more pronounced on small glaciers at low altitudes that do not have a permanent accumulation zone, and which could disappear in the coming years/decades. Monthly mass balance measurements performed in Bolivia, Ecuador and Colombia showed that variability of the surface temperature of the Pacific Ocean is the main factor governing variability of the mass balance variability at the interannual to decadal time scale. Precipitation did not display a significant trend in the tropical Andes in the 20th century, and consequently cannot explain the glacier recession. On the other hand, temperature increased at a significant rate of 0.10 °C decade−1 in the last 70 yr. The higher frequency of El Niño events and changes in its spatial and temporal occurrence since the late 1970s together with a warming troposphere over the tropical Andes may thus explain much of the recent dramatic shrinkage of glaciers in this part of the world.