Topic: Coupled impacts of climate and land use change across a river-lake continuum: insights from an integrated assessment model of Lake Champlain’s Missisquoi Basin, 2000-2040
Speaker: Asim Zia, PhD, Associate Professor of Public Policy & Decision Analysis: Department of Community Development and Applied Economics &
Department of Computer Science at the University of Vermont
Abstract: Global climate change (GCC) will bring higher-intensity precipitation and higher-variability temperature regimes to the Northeastern United States. The interactive effects of GCC with anthropogenic land use and land cover changes (LULCC) are unknown for watershed level hydrological dynamics and nutrient fluxes to freshwater lakes. Increased nutrient fluxes can promote harmful algal blooms, also exacerbated by warmer water temperatures due to GCC. To address the complex interactions of climate, land and humans, we developed a cascading integrated assessment model to test the impacts of GCC and LULCC on the hydrological regime, water temperature, water quality, bloom duration and severity through 2040 in transnational Lake Champlain’s Missisquoi Bay. Temperature and precipitation inputs were statistically down-scaled from four Global Circulation Models (GCMs) for three Representative Concentration Pathways. An agent-based model was used to generate four LULCC scenarios. Combined climate and LULCC scenarios drove a distributed hydrological model to estimate river discharge and nutrient input to the lake. Lake nutrient dynamics were simulated with a 3-D hydrodynamic-biogeochemical model. We find accelerated GCC could drastically limit land management options to maintain water quality, but the nature and severity of this impact varies dramatically by GCM and GCC scenario.
Bio: Dr. Asim Zia is currently serving as an Associate Professor of Public Policy and Decision Analysis in the Department of Community Development and Applied Economics, with a secondary appointment in the Department of Computer Science, at the University of Vermont. He is Associate Director of Vermont EPSCOR, Director of the Institute for Environmental Diplomacy and Security (IEDS) and Co-Director of the Social Ecological Gaming and Simulation (SEGS) lab at the University of Vermont. Dr. Zia is undertaking NSF funded work on developing computational integrated assessment models that project and quantify high-resolution impacts of global climate change and land-use land cover change on watershed scale hydrological systems and lake systems, and their feedback on social systems. Dr. Zia has published widely on international climate policy, management of social ecological systems, risk communication, risk management, international development, tropical forest conservation, and adaptation to climate change in the US, Latin American, African and Asian contexts. He is also working on grant funded projects pertaining to mainstreaming early warning systems in development and planning processes; spatial planning, optimization and control to ensure food, energy and water security in the face of climate change induced extreme events, and designing institutions and governance networks to assess and mitigate risks from environmental, social and political drivers of change. Asim Zia has published more than forty peer-reviewed articles/book chapters and three books.