ANDEX: A Hydroclimate Research Program for the Andes and a Prospective GEWEX Regional Hydroclimate Project (RHP)

SARA M. VALLEJO; PAOLA A. ARIAS; JHAN CARLO ESPINOZA; GERMAN POVEDA; JOSE; D. PABON; PETER J. VAN OEVELEN; SILVINA SOLMAN; JORGE MOLINA; JOAN CUXART; RENE; GARREAUD

Canmore

Conferencia; 8TH GEWEX OPEN SCIENCE CONFERENCE; 2018

GEWEX - WCRP

We propose to establish a comprehensive hydroclimate research program for the Andes of South America (ANDEX), as a prospective GEWEX Regional Hydroclimate Project (RHP). It aims at understanding, modelling and predicting the dynamics of water and energy cycles over the Andes, from north to south, and from west to east, at a wide range of temporal and spatial scales, and their linkages with the surrounding oceans and major river basins. The Andes constitute the world?s longest mountain range, extending through 7,242 km, from the northern Caribbean coast (12N) to the southern tip of South America (50S). The range is about 200 to 700 km wide (widest between 18°S-20°S), and its average height 4,000 m. The Andes runs through seven South American countries: Venezuela, Colombia, Ecuador, Peru, Bolivia, Argentina and Chile. Owing to its long north-south extent the Andes exhibit strong hydroclimatic variability associated with Latitudinal and Hemispheric location, but also with aspect, slope and elevation. The Andes contain glaciers, volcanoes, deserts, high plateaus, lakes, páramos, yungas, punas, cloud forests, wet forests, tropical rainforests, dry forests, savannas, and intra-mountainous valleys. The Andes are considered the water tower of South America, and contain some of the wettest regions on Earth on the Colombian western Andean slope to the driest one over the Atacama Desert in Chile. The region faces enormous challenges from human pressure (85 million people) and from climate and global environmental change, not the least of which are the retreat and disappearance of tropical glaciers, with important implications for water supply, biodiversity, and the sustainability of páramos and cloud forests, and other ecosystems. The mountainous areas of the Andes harbor major cities and hundreds of medium and small sized towns demanding an ever-increasing supply of environmental services and socio-economic resources. The Andean population are highly vulnerable to extreme and intense storms leading to avalanches, landslides and flooding affecting human lives, and destructing roads, bridges, houses, water and energy supply systems, infrastructure, and crops.A degraded environment affects the well-being of human communities of the Andes, in terms of its failure to provide natural resources such as fresh drinking water and a sound agricultural basis. Poverty in the Andean region, the disappearance of native and ancestral cultures, human encroachment, large scale deforestation, erosion and land degradation, landslides and debris flows, increasing vulnerability and risk of human populations and settlements, accelerated loss of biodiversity and soils, large-scale pollution of water sources owing to mining activities, oil industry activities, agriculture, cattle dwellers, tourists, coca growers, makes it all the more urgent that basic studies and applied research need to be carried out urgently. At the same time, a suite of opportunities arises from the region?s natural biodiversity, and from the breadth of current and potential environmental services provided by their ecosystems, and the considerable possibilities of sustainable development of the region. Therefore, a thorough understanding of the Andes system is necessary, including the interactions between natural ecosystems and social systems. Between December 4-6, 2017, the authors met in Medellín, Colombia, to hold the ANDEX preparatory meeting and to summarize the current understanding of the Andean hydroclimate. We also recognized the urgent need to link the physical scientific understanding with an ample array of societal needs (e.g., water, food security, human health, hydropower, navigation, and disasters, among others). During the Medellín meeting more than 40 research questions were identified and grouped into four major science themes: (1) Climate Patterns and Drivers, (2) Climate and Environmental Changes, (3) High Impact Events, and (4) Andean Cryosphere. Also, diverse cross-cutting themes were considered such as: (i) Observations, Data and Modeling, and (ii) Science Underpinning Sustainable Development. A ?white paper? addressing these issues will be prepared during the first semester of 2018, emphasizing in each case actions and challenges to bridge the current gaps in knowledge and applications. The ANDEX white paper will serve a basis for a Science and Implementation Plan that should be developed after a second ANDEX meeting to be held in Santiago, Chile, in October 2018. Also, the proposed agenda will further the scientific development in South America through: (i) fostering regional cooperation among researchers and research programs, (ii) establishing a focused research agenda on fundamental issues of the Andes region main interests, (iii) creating the scientific framework to help decision making processes for the sustainable development of a highly environmentally and biogeophysically threatened region, (iv) connecting the Andean region with global and regional initiatives.