Grantee Research Project Results
2018 Progress Report: Wildfires in the Rocky Mountains Region: Current and Future Impacts on PM2.5, Health, and Policy
EPA Grant Number: R835869Title: Wildfires in the Rocky Mountains Region: Current and Future Impacts on PM2.5, Health, and Policy
Investigators: Liu, Yang , Strickland, Matthew J , Chang, Howard , Fu, Joshua , Liu, Yongqiang
Institution: Rollins School of Public Health, Emory University , U.S. Forest Service , University of Nevada - Reno , University of Tennessee
Current Institution: Rollins School of Public Health, Emory University , University of Nevada - Reno , University of Tennessee , U.S. Forest Service
EPA Project Officer: Keating, Terry
Project Period: January 1, 2016 through December 31, 2018 (Extended to December 31, 2020)
Project Period Covered by this Report: January 1, 2018 through December 31,2018
Project Amount: $786,089
RFA: Particulate Matter and Related Pollutants in a Changing World (2014) RFA Text | Recipients Lists
Research Category: Air , Climate Change , Air Quality and Air Toxics
Objective:
In recent decades, the western United States has seen heightened wildfire activity, characterized by a higher frequency of large wildfires a longer fire season, larger fire size, and a greater total area burned. With projected temperature increases, soil moisture reduction, and more frequent air stagnation, the burden of wildfires on air quality, public health, and environmental management will likely increase. With state-of-the-art global climate, regional climate, and air quality models; ground and satellite measurements; and detailed health information, we propose to investigate the impacts of historical and future wildfires on air quality, public health, and environmental management in the Rocky Mountains Region under various climate change scenarios and population growth patterns.
Progress Summary:
Using a hybrid downscaling approach, we evaluated the separate impact of climate change and emission control policies on O3 levels and associated excess mortality in the United States in the 2050s under two Representative Concentration Pathways (RCPs). We show that, by the 2050s, under RCP4.5, increased O3 levels due to combined climate change and emission control policies, could contribute to an increase of approximately 50 premature deaths annually nationwide in the United States. The biggest impact, however, is seen under RCP8.5, where rises in O3 concentrations are expected to result in over 2,200 additional premature deaths annually. The largest increases in O3 are seen in RCP8.5 in the Northeast, the Southeast, the Central, and the West regions of the United States. Additionally, when O3 increases are examined by climate change and emissions contributions separately, the benefits of emissions mitigation efforts may significantly outweigh the effects of climate change mitigation policies on O3-related mortality. This work has been published in Environment International.
Epidemiological studies on wildfire PM2.5 are limited by the lack of accurate high-resolution PM2.5 exposure data over fire days. Satellite-based aerosol optical depth (AOD) data can provide additional information in ground PM2.5 concentrations and has been widely used in previous studies. However, the low background concentration, complex terrain and large wildfire sources add to the challenge of estimating PM2.5 concentrations in the western United States. In this study, we applied a Bayesian ensemble model that combined information from the 1 km resolution AOD products derived from the Multi-angle Implementation of Atmospheric Correction (MAIAC) algorithm, Community Multi-scale Air Quality (CMAQ) model simulations and ground measurements to predict daily PM2.5 concentrations over fire seasons (April to September) in Colorado for 2011−2014. Our model had a ten-fold cross validated R2 of 0.66 and root-mean-squared error of 2.00 micrograms/m3, outperforming the multi-stage model, especially on fire days. Elevated PM2.5 concentrations over large fire events were successfully captured. The modeling technique demonstrated in this study could support future short-term and long-term epidemiological studies of wildfire PM2.5. This work has been accepted by the Journal of Geophysical Research-Atmosphere.
PI Yang Liu participated in the preparation of a commentary article led by Co-I Prof. Howard Chang on projection of the health impacts of climate change in the United States. This work was published in the journal Chance.
Based on the successful modeling experiences for the Colorado case, we expanded our modeling domain to the western United States (see Fig. 1) region and conducted simulations using data from the U.S. EPA for the present years (2001–2010). Results demonstrated monthly mean PM2.5 concentration variations caused by wildfires could be as large as 195 micrograms/m3 and 10 ppb for O3 in July 2008 in California.
To perform CMAQ simulations for the future years (2050–2059), we obtained the RCP8.5 emission database from the International Institute for Applied Systems Analysis (IIASA) that included 12 emission sectors. The future fire-induced monthly mean PM2.5 changes were up to 58 micrograms/m3 in August 2054 and 2.5 ppb for monthly mean O3 changes in August 2055 in Idaho. Since the RCP8.5 emissions from IIASA had the spatial resolution of 0.5°×0.5°, we replaced the fire emissions in the RCP8.5 by a new fire emission data set from the outputs of an empirical fire model developed based on the extreme value theory. Through this fire model, we simulated wildfires and the related PM2.5 emissions in the western United States for 2001–2010 and projected for 2050–2059. The weather factors for fire prediction are a fire danger index at various abnormal levels and air humidity conditions corresponding to these levels. The model was developed for each of several fire size ranges. The data used to develop the fire model were historical fire and weather. The climate data for simulating and projecting fire were from dynamical regional climate downscaling. The properties used to estimate fire emission included projected fires, fuel loading, and fuel moisture. The results were presented at the 6th International Fire Behavior and Fuel Conference.
Future Activities:
In the extension year of our project, we will (1) finish the CMAQ simulations for future years in the western United States, (2) complete the epidemiologic study to link smoke PM2.5 to Emergency Department (ED) visits and hospitalization in Colorado, (3) complete the estimation of the impacts of future wildfires and urban pollution on air quality, population health, and public health decision making in the Rocky Mountains Region.
Specifically, we will continue working on the preparations of future year emissions for CMAQ v5.2 for the Western United States case. We will conduct the future fire and no-fire CMAQ simulations using the fire emissions from the fire model by Dr. Yongqiang Liu. We will compare the three cases— RCP8.5 fire, RCP8.5 no fire, and RCP8.5 with Liu’s fire—to investigate the impacts of future wildfires on the air pollution and environment in the Western United States.
Journal Articles on this Report : 2 Displayed | Download in RIS Format
Other project views: | All 24 publications | 14 publications in selected types | All 14 journal articles |
---|
Type | Citation | ||
---|---|---|---|
|
Geng G, Murray N, Tong D, Fu J, Hu X, Lee P, Meng X, Chang H, Liu Y. Satellite-based daily PM2.5 estimates during fire season in Colorado. Journal of Geophysical Research:Atmospheres 2018;123:8159-8171. |
R835869 (2018) |
Exit Exit |
|
Geng G, Murray N, Chang H, Liu Y. The sensitivity of satellite-based PM2.5 estimates to its inputs: implications to model development in data-poor regions. Environment International 2018;121:550-560. |
R835869 (2018) |
|
Supplemental Keywords:
Particulate Matter, PM2.5, Wildfires, CESM, WRF-CMAQ, dynamical downscaling
Progress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.