Effects of Changes in Climate and Land Use on U.S. Dust and Wildfire Particulate MatterEPA Grant Number: R835875
Title: Effects of Changes in Climate and Land Use on U.S. Dust and Wildfire Particulate Matter
Investigators: Mickley, Loretta J. , Jacob, Daniel J. , Kaplan, Jed
Institution: Harvard University , ARVE Research Sarl
EPA Project Officer: Chung, Serena
Project Period: January 1, 2016 through December 31, 2018 (Extended to December 31, 2020)
Project Amount: $719,780
RFA: Particulate Matter and Related Pollutants in a Changing World (2014) RFA Text | Recipients Lists
Research Category: Air , Climate Change
Changes in climate and land use could adversely affect surface levels of particulate matter (PM), with consequences for human health and visibility. Our project will better quantify the effects of these changes on dust and smoke burdens across the United States over the present-2050 time frame. We will focus in particular on the West and Southwest. These regions are projected to become warmer and more arid in coming decades, with potentially large impacts on dust and wildfire PM.
Project goals are as follows: (1) to quantify the effects of climate change and land use on dust mobilization and transport within the western United States; (2) to quantify the impact of climate change on Asian dust influence over the western United States; and (3) to provide fine-scale projections of wildfire smoke for the future climate in the West.
Our project takes advantage of the large array of climate projections archived by the Coupled Model Intercomparison Project (CMIP5) in support of the Intergovernmental Panel on Climate Change (IPCC). To quantify the impact of changing climate and land use on dust mobilization, we will use the chemical transport model GEOS-Chem at 0.25o x 0.3125o (~25 x 25 km2) horizontal resolution over North America for the 2000-2050 timeframe. Information on land cover change will be provided by LPJ-LMfire, a dynamic vegetation model which we will drive with CMIP5 meteorology and land use scenarios. To quantify the effect of changing climate on both dust mobilization and transport, we will identify the main meteorological modes driving dust PM in the West, and then examine trends in these modes in the CMIP5 projections. We will take a similar approach to quantify the impact of changing climate on transpacific transport of Asian dust and its influence on PM levels in the West. These steps will enable us to exploit the climate projections from an ensemble of over 20 global climate models contributing to CMIP5, thus providing robustness and uncertainty estimates to our results. To better understand the mechanisms driving the effects of climate change on dust, we will conduct coupled aerosol-climate simulations with the NASA/GISS climate model linked to GEOS-Chem. Finally, we will build on our past efforts and provide fine-scale projections of wildfire smoke in the West. Here again we will rely on the CMIP5 climate projections, this time to quantify the effects of changing climate on area burned and fire emissions.
Results from our project will better prepare environmental managers for the challenges of regulating air quality in a changing world. Our use of the CMIP5 ensemble will allow us to assess with greater confidence the climate penalty for dust and wildfire PM in the western United States. More specifically, we will determine how climate change will affect the spatiotemporal patterns or environmental impacts of PM in the United States over the coming decades, and we will identify the robust lessons that can be learned regarding future PM. Our work will also quantify the effects of changing land use on dust PM.