Kenneth Young: Climate change, people, and mountains

Glacial Flooding & Disaster Risk Management Knowledge Exchange and Field Training July 11-24, 2013 in Huaraz, Peru HighMountains.org/workshop/peru-2013

Climate Change, People, and Mountains Kenneth R. Young Department of Geography and the Environment University of Texas at Austin kryoung@austin.utexas.edu Mountains create both opportunities in terms of natural resources and ecosystem services, and also risks given geomorphic instability and a high susceptibility to climate change consequences. Thus, the processes that connect people to mountains need to be understood in terms of their couplings, feedbacks, interactions, and responses to global change. While risks posed by changes in high mountains can be dealt with through education, outreach, and engineering interventions, better for a more complete understanding would be to evaluate the coupled natural-­‐human systems involved in a way that permits comparisons among the different highland regions of the world.

The land covers of mountains include glaciers, water bodies, natural vegetation types, and also crops, pastures, orchards, tree plantings, and settlements. Change in these respective land covers through time may suggest, for example, increasing temperatures if glaciers are shrinking and glacial lakes expanding. In turn, changes in land cover associated with the livelihoods of rural people or the expansion of towns and cities, serve to indicate a set of social and economic processes associated with demographic shifts, and with local and regional development.

Relatively new research approaches that explicitly link biophysical and socio-­‐ economic processes are now available. They can be valuable for documenting, evaluating, and modelling landscape changes arising from the interactions of natural with cultural realms. These are coupled natural-­‐human systems research paradigms. They, provide a framework for interdisciplinary research drawing on human resources and methodologies from the geosciences, the biological sciences, engineering, the social sciences, and the humanities.

As an example, Bury et al. (2013; New Geographies of Water and Climate Change in Peru: Coupled Natural and Social Transformations in the Santa River Watershed; Annals of the Association of American Geographers 103: 363-­‐375) report on the findings of a project funded by the U.S. National Science Foundation program entitled “Dynamics of coupled natural-­‐human systems”. They were able to use ice coverage and stream discharge data to project consequences for water availability in Peru’s Santa River Basin. The highest elevations of this basin include the hundreds of glaciers of the Cordillera Blanca, which have receded some 25% in the last several decades. The glaciers are inside the boundaries of Huascaran National Park, giving them conservation, recreation, and touristic values. The

high elevation ecosystems are changing with the ongoing warming trend, including for example high elevation proglacial wetlands that first expanded and are now contracting as peak water has passed through the regional hydrograph. Meanwhile, glacial risks continue to increase, while social and economic shifts have altered perceptions of risk by local people, and water demands across the basin. In fact, despite declining water supplies, demands for hydropower, for mining operations, and for potable water have all increased substantially. Much of the River Santa’s water begins as snow and ice, but ends up being used for export agriculture, for producing sugar cane, asparagus, avocados and other crops.

Trying to understand the current and possible future dynamics of this particular study area required a coupled system approach, done within a watershed context, and as evaluated by a glaciologist/physical geographer (Brian Marcus), a hydrologist (Jeffrey McKenzie), a biogeographer (Kenneth Young), a human geographer (Jeffrey Bury), and an environmental historian (Mark Carey). The coupled system approach provided a means to ask complex transdisciplinary questions about a large mountain gradient. It facilitated group interactions and goals in terms of the kinds of research questions asked and the sorts of data analyzed.

In conclusion, environmental and social changes in the high mountains are complex, with many drivers of change originating far away in global climate processes, and also as affected by national, regional, and global markets setting economic costs and benefits.

There are inevitable trade-­‐offs among adaptation strategies to deal with natural hazards and livelihoods, while also taking into account biodiversity, carbon dynamics, and the hydrological cycle. Integrated and interdisciplinary approaches are needed for planning and for providing recommendations to decision makers.