Pacific Northwest National Laboratory (PNNL), in partnership with Oak Ridge National Laboratory (ORNL), is developing and applying a regional integrated assessment and Earth system modeling framework to the Gulf Coast region of the United States—a region where climate impacts and adaptation, agriculture and land use issues, coastal issues, and energy supply issues are all occurring simultaneously, but for which integrated modeling has not been seriously attempted. One of the main objectives of the project is to understand the implications of integrated modeling at regional scales, especially how those insights might differ from those derived from models at coarser spatial scales. The project will also generate new insights into the following four overarching research questions:
- What are the regional characteristics and opportunities for mitigation and adaptation strategies? For example, are there physical (e.g., the availability of water or sufficient soil fertility) or economic (e.g., the availability of physical infrastructure) constraints that make the implementation of different energy technologies (e.g., biofuels) or mitigation strategies (e.g., carbon capture and storage) more difficult, but that are only appreciated when simulations are done with greater regional specificity than the national or international strategies that are done today?
- How do changes in mean climate and climate variability affect adaptation and mitigation strategies?
- What are the interactions between management decisions and natural processes that contribute to rapid, or nonlinear changes in the environment? Where are such nonlinearities, and how do their consequences contribute to climate feedbacks?
- How will adaptation and mitigation strategies interact in the next few decades?
This project takes advantage of the Platform for Regional Integrated Modeling and Analysis (PRIMA) framework being developed at PNNL to link regional climate, integrated assessment, energy, land, and hydrologic components to form a spatially flexible and temporally dynamic modeling framework. A key component of the PRIMA framework is a regionalized version of the Global Change Assessment Model (GCAM), for which this project is being extended and downscaled to improve the representation of specific Gulf Coast energy infrastructure, coastal processes, land management technologies, and biogeophysical responses to climate change. The regional modeling framework will be constrained by global boundary conditions provided by GCAM and the Community Climate System Model (CCSM), which are driven by the newly developed representative concentration pathways (RCPs). Regional climate scenarios for the Gulf Coast will be developed by downscaling CCSM results using the Weather Research and Forecasting (WRF) regional climate model coupled with the Regional Ocean Model System (ROMS). Biophysical information will be applied to impacts models to assess climate change impacts both for individual sectors (such as agriculture) and across the land-water-energy nexus. A range of mitigation and adaptation experiments will subsequently be applied to test the costs, benefits, and trade-offs associated with different policy options for addressing the risks of climate change in the Gulf coast. The implementation of this integrated regional modeling approach will not only illustrate the consequences of potential actions by regional stakeholders, but also improve our general understanding of multi-scale modeling challenges and of the interdependencies among human and natural systems in the context of climate change.