2014 Progress Report: Combining Empirical Orthogonal Function and Extreme Value Theory Methods to Characterize Observed and Future Changes in Extreme U.S. Air Pollution Events

EPA Grant Number: R835206
Title: Combining Empirical Orthogonal Function and Extreme Value Theory Methods to Characterize Observed and Future Changes in Extreme U.S. Air Pollution Events
Investigators: Fiore, Arlene M , Polvani, Lorenzo M
Institution: Columbia University in the City of New York
EPA Project Officer: Chung, Serena
Project Period: June 1, 2012 through May 31, 2015 (Extended to May 31, 2016)
Project Period Covered by this Report: June 1, 2014 through June 1,2015
Project Amount: $749,951
RFA: Extreme Event Impacts on Air Quality and Water Quality with a Changing Global Climate (2011) RFA Text |  Recipients Lists
Research Category: Air Quality and Air Toxics , Water Quality , Climate Change , Air , Water


With a suite of observations and models, we identify and characterize changes in extreme ozone and particulate matter events and their underlying drivers over the past several decades, as well as for a variety of future climate and emission scenarios. We examine changes in extreme temperature and precipitation events to provide information on key hazards affecting air and water quality.

Progress Summary:

We have characterized changes in extreme surface ozone events over the Eastern United States separately under climate change and combined climate and pollutant emission scenarios. In order to estimate changes in policy-relevant statistics, despite baseline biases in a chemistry-climate model, we have developed and applied a statistical bias correction at the regional scale. We found that observed surface ozone seasonal cycles over the Northeastern United States are shifting in response to regional precursor emission controls and further examined how they respond to changes in regional precursor emission controls, global methane, and climate change in a chemistry-climate model. We conclude that continued changes in the balance between regional ozone production and background ozone could lead to a reversal of the seasonal cycle in presently polluted regions over the coming decades, thereby altering the baseline upon which extreme ozone pollution events build. We are exploring the role of aerosols versus greenhouse gases in contributing to changes in extreme precipitation and temperature events over the United States. We are evaluating these forced responses relative to climate variability and further examining how they change under scenarios in which climate warms and air pollutant emissions decline. We have published a review on U.S. air quality and climate change, including extreme pollution events.

Future Activities:

We are extending our work to other U.S. regions and seasons, and examining PM2.5 pollution. We are working to advance mechanistic understanding of extreme temperature, precipitation, pollution events and their joint occurrence. We are developing approaches to project changes based on coarse chemistry-climate models at the local scale, and to apply EOF analysis to identify extreme events and changes in their frequency and duration. To the extent possible, we will examine other models to determine where projected changes are most robust.

Journal Articles on this Report : 4 Displayed | Download in RIS Format

Other project views: All 48 publications 11 publications in selected types All 11 journal articles
Type Citation Project Document Sources
Journal Article Clifton OE, Fiore AM, Correa G, Horowitz LW, Naik V. Twenty-first century reversal of the surface ozone seasonal cycle over the northeastern United States. Geophysical Research Letters 2014;41(20):7343-7350. R835206 (2013)
R835206 (2014)
R835206 (Final)
  • Full-text: UCAR-Full Text PDF
  • Abstract: Wiley Online-Abstract
  • Other: Wiley Online-Full Text PDF
  • Journal Article Fiore AM, Naik V, Leibensperger EM. Air quality and climate connections. Journal of the Air & Waste Management Association 2015;65(6):645-685. R835206 (2014)
    R835206 (Final)
  • Abstract from PubMed
  • Full-text: Taylor & Francis-Full Text HTML
  • Abstract: Taylor & Francis-Abstract
  • Other: Taylor & Francis-Full Text PDF
  • Journal Article Mascioli NR, Fiore AM, Previdi M, Correa G. Temperature and precipitation extremes in the United States: quantifying the responses to anthropogenic aerosols and greenhouse gases. Journal of Climate 2016;29(7):2689-2701. R835206 (2014)
    R835206 (Final)
  • Full-text: Columbia University-Full Text PDF (prepublication)
  • Abstract: AMS-Abstract
  • Journal Article Rieder HE, Fiore AM, Horowitz LW, Naik V. Projecting policy-relevant metrics for high summertime ozone pollution events over the eastern United States due to climate and emission changes during the 21st century. Journal of Geophysical Research:Atmospheres 2015;120(2):784-800. R835206 (2013)
    R835206 (2014)
    R835206 (Final)
  • Full-text: Columbia University-Full Text PDF
  • Abstract: Wiley Online-Abstract
  • Supplemental Keywords:

    ambient air, global climate, precipitation, sustainable air quality management, sustainable water management, global change, regional climate change, air pollution episodes, ozone, aerosol, modeling, general circulation models, climate models

    Relevant Websites:

    Fiore Atmospheric Chemistry Group: Group Presentations Exit
    Fiore Atmospheric Chemistry Group: Datasets Exit

    Progress and Final Reports:

    Original Abstract
  • 2012 Progress Report
  • 2013 Progress Report
  • Final Report