2019 Progress Report: Effects of Changes in Climate and Land Use on U.S. Dust and Wildfire Particulate Matter

EPA 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 Period Covered by this Report: January 1, 2019 through December 31,2019
Project Amount: $719,780
RFA: Particulate Matter and Related Pollutants in a Changing World (2014) RFA Text |  Recipients Lists
Research Category: Air , Climate Change

Objective:

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.

Progress Summary:

Activities 1 and 2. Postdoc Yang Li investigated the influence of future changes in climate and land cover on lightning-caused wildfires in National Forests and Parks of the western United States. She then diagnosed the consequences of these fires on air quality. Working with consultant Jed Kaplan, Li linked a dynamic vegetation model that includes a process-based representation of fire (LPJ-LMfire) to a global chemical transport model (GEOS-Chem).

Li also assessed the impacts of future changes in climate, CO2 fertilization, and land use practices on dust mobilization in the desert Southwest, with a goal to investigate the consequences for surface air quality. Again she worked with Kaplan to link LPJ-LMfire with GEOS-Chem.

Both these projects took into account the effect of changing climate on vegetation, an effect that is sometimes neglected in model studies of air quality. For dust, the effect of increased CO2 fertilization on vegetative growth was also considered.

Activity 3. Working with former student Pattanun (Ploy) Achakulwisut and collaborators at George Washington University, we used observations and statistical methods to demonstrate that fine and coarse dust levels in the Southwest are strongly sensitive to soil moisture variability across this region. We estimated potential changes in dust levels through 2099 by applying these observed sensitivities to downscaled meteorological output projected by six climate models following an intermediate (RCP4.5) and a high (RCP8.5) greenhouse gas concentration scenario. We then quantified the health and economic consequences of changing dust in the Southwest.

2019 Outcomes

Project 1. Lightning fires and smoke concentrations in the western United States. Under a scenario of moderate future climate change (RCP4.5), increasing lightning-caused wildfire enhances the burden of smoke fine particulate matter (PM), with mass concentration increases of ~53% by the late-21st century during the fire season. In a high-emissions scenario (RCP8.5), smoke PM concentrations double by 2100. RCP8.5 also shows large, northward shifts in dry matter burned, leading to enhanced lightning-caused fire activity especially over forests in the northern states.

Project 2. Future dust burden in the Southwest, with changing vegetation. We find a mix of trends in the late-21st century over the southwestern United States, during springtime, the season of maximum dust emissions. Fine dust emissions decrease over Arizona and New Mexico but increase emissions along Mexico's northern border These trends result from more densely vegetated environments in the arid southwestern U.S. under future climate, but sparser vegetation in northern Mexico. The two main drivers of dust trends in this region – CO2 fertilization and land use intensification – play opposing roles, with the first driver enhancing vegetation and thus decreasing dust in the southwestern U.S. and the second driver increasing dust in northern Mexico. In the absence of CO2 fertilization, the RCP8.5 scenario places an upper bound on increases in dust, with elevated concentrations widespread over the southwestern North America by 2100 in spring, especially in southeastern New Mexico (up to ~2.0 mg m-3) and along the border between New Mexico and Mexico (up to ~2.5 mg m-3).

Project 3. Future dust burden in the Southwest, with implications for public health. We found the following outcomes for dust levels in the Southwest by 2080-2099 under RCP8.5 relative to 1986-2005. (1) Fine dust levels could increase by 57%, and fine dust-attributable all-cause mortality and hospitalizations could increase by 220% and 350%, respectively. (2) Coarse dust levels could increase by 38%, and coarse-dust attributable cardiovascular mortality and asthma emergency department visits could increase by 210% and 90%, respectively. (3) Climate-driven changes in dust concentrations can account for 34-47% of these health impacts, with the rest due to increases in population and baseline incidence rates; (4) Economic damages of the health impacts are estimated to be $47 billion/year (additional to the 1986-2005 value of $13 billion/year). Following RCP4.5 rather than RCP8.5 could reduce dust-related mortality and morbidity by ~30% in 2050 and ~60% in 2090. Compared to the national-scale climate impacts projected for other US sectors, estimated dust-related economic damages rank fourth, behind extreme temperature, labor, and coastal property.

Future Activities:

In Year 5 we will wrap up work on Projects 1 and 2, described above, and submit to journals.


Journal Articles on this Report : 5 Displayed | Download in RIS Format

Other project views: All 10 publications 7 publications in selected types All 7 journal articles
Type Citation Project Document Sources
Journal Article Achakulwisut P, Shen L, Mickley LJ. What controls springtime fine dust variability in the western United States? Investigating the 2002–2015 increase in fine dust in the U.S. Southwest. Journal of Geophysical Research: Atmospheres 2017;122(22):12449-12467.
abstract available   full text available
R835875 (2017)
R835875 (2018)
R835875 (2019)
R835875 (Final)
  • Full-text: SemanticScholar-Full Text PDF
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  • Abstract: Wiley-Abstract
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  • Journal Article Lin M, Horowitz LW, Payton R, Fiore AM, Tonnesen G. US surface ozone trends and extremes from 1980 to 2014: quantifying the roles of rising Asian emissions, domestic controls, wildfires, and climate. Atmospheric Chemistry and Physics 2017;17(4):2943-2970.
    abstract available   full text available
    R835875 (2017)
    R835875 (2019)
    R835875 (Final)
    R835878 (2016)
    R835878 (2017)
    R835878 (2018)
    R835878 (2019)
    R835878 (Final)
  • Abstract: AOS-Abstract
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  • Other: ACP-Full Text PDF
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  • Journal Article Liu JC, Wilson A, Mickley LJ, Ebisu K, Sulprizio MP, Wang Y, Peng RD, Yue X, Dominici F, Bell ML. Who among the elderly is most vulnerable to exposure to and health risks of fine particulate matter from wildfire smoke? American Journal of Epidemiology 2017;186(6):730-735.
    abstract available   full text available
    R835875 (2017)
    R835875 (2018)
    R835875 (2019)
    R835875 (Final)
    R834798 (Final)
    R835871 (2017)
    R835871 (2018)
    R835871 (2020)
  • Full-text from PubMed
  • Abstract from PubMed
  • Associated PubMed link
  • Full-text: OUP-Full Text HTML
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  • Other: OUP-Full Text PDF
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  • Journal Article Achakulwisut P, Mickley LJ, Anenberg SC. Drought-sensitive of fine dust variability in the western United States? Implications for the recent dust increase in the Southwest:implications for air quality and public health under future climate change. Environmental Research Letters 2018;13(5):54025
    abstract available   full text available
    R835875 (2018)
    R835875 (2019)
    R835875 (Final)
  • Full-text: Environmental Research Letters - Full Text HTML and PDF
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  • Journal Article Achakulwisut P, Anenberg SC, Neumann JE, Penn SL, Weiss N, Crimmins A, Fann N, Martinich J, Roman J, Mickley LJ. Effects of increasing aridity on ambient dust and public health in the US Southwest under climate change. American Geophysical Union GeoHealth 2019;3(5):127-144.
    abstract available   full text available
    R835875 (2018)
    R835875 (2019)
    R835875 (Final)
  • Full-text from PubMed
  • Abstract from PubMed
  • Full-text: AGU 100 - Full Text HTML and PDF
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  • Other: AGU 100 - Full Text PDF
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  • Supplemental Keywords:

    intercontinental transport, climate change

    Progress and Final Reports:

    Original Abstract
  • 2016 Progress Report
  • 2017 Progress Report
  • 2018 Progress Report
  • Final Report