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Development of a regional-scale pollen emission and transport modeling framework for investigating the impact of climate change on allergic airway disease

Zhang, R. and Duhl, T. and Salam, M. T. and House, J. M. and Flagan, R. C. and Avol, E. L. and Gilliland, F. D. and Guenther, A. and Chung, S. H. and Lamb, B. K. and VanReken, T. M. (2014) Development of a regional-scale pollen emission and transport modeling framework for investigating the impact of climate change on allergic airway disease. Biogeosciences, 11 (6). pp. 1461-1478. ISSN 1726-4170. PMCID PMC4021721. doi:10.5194/bg-11-1461-2014.

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Exposure to bioaerosol allergens such as pollen can cause exacerbations of allergenic airway disease (AAD) in sensitive populations, and thus cause serious public health problems. Assessing these health impacts by linking the airborne pollen levels, concentrations of respirable allergenic material, and human allergenic response under current and future climate conditions is a key step toward developing preventive and adaptive actions. To that end, a regional-scale pollen emission and transport modeling framework was developed that treats allergenic pollens as non-reactive tracers within the coupled Weather Research and Forecasting Community Multiscale Air Quality (WRF/CMAQ) modeling system. The Simulator of the Timing and Magnitude of Pollen Season (STaMPS) model was used to generate a daily pollen pool that can then be emitted into the atmosphere by wind. The STaMPS is driven by species-specific meteorological (temperature and/or precipitation) threshold conditions and is designed to be flexible with respect to its representation of vegetation species and plant functional types (PFTs). The hourly pollen emission flux was parameterized by considering the pollen pool, friction velocity, and wind threshold values. The dry deposition velocity of each species of pollen was estimated based on pollen grain size and density. An evaluation of the pollen modeling framework was conducted for southern California (USA) for the period from March to June 2010. This period coincided with observations by the University of Southern California's Children's Health Study (CHS), which included O3, PM2.5, and pollen count, as well as measurements of exhaled nitric oxide in study participants. Two nesting domains with horizontal resolutions of 12 and 4 km were constructed, and six representative allergenic pollen genera were included: birch tree, walnut tree, mulberry tree, olive tree, oak tree, and brome grasses. Under the current parameterization scheme, the modeling framework tends to underestimate walnut and peak oak pollen concentrations, and tends to overestimate grass pollen concentrations. The model shows reasonable agreement with observed birch, olive, and mulberry tree pollen concentrations. Sensitivity studies suggest that the estimation of the pollen pool is a major source of uncertainty for simulated pollen concentrations. Achieving agreement between emission modeling and observed pattern of pollen releases is the key for successful pollen concentration simulations.

Item Type:Article
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URLURL TypeDescription CentralArticle
Flagan, R. C.0000-0001-5690-770X
VanReken, T. M.0000-0002-2645-4911
Additional Information:© 2014 The Author(S). Published by Copernicus Publications on behalf of the European Geosciences Union. This work is distributed under the Creative Commons Attribution 3.0 License. Received: 31 January 2013; Published in Biogeosciences Discuss.: 1 March 2013 Revised: 16 September 2013; Accepted: 5 February 2014; Published: 19 March 2014. The authors would like to acknowledge funding for this project via US EPA grant R8343580. Although the research described in this article has been funded wholly or in part by the United States Environmental Protection Agency through EPA STAR grant R834358, it has not been subjected to the Agency’s required peer and policy review and therefore does not necessarily reflect the views of the Agency and no official endorsement should be inferred. The authors also would like to thank Jeremy Avise of the California Air Resource Board for providing the meteorological observation data used for model evaluation.
Funding AgencyGrant Number
Environmental Protection Agency (EPA)R8343580
Environmental Protection Agency (EPA)R834358
Issue or Number:6
PubMed Central ID:PMC4021721
Record Number:CaltechAUTHORS:20140512-105529114
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Official Citation:Zhang, R., Duhl, T., Salam, M. T., House, J. M., Flagan, R. C., Avol, E. L., Gilliland, F. D., Guenther, A., Chung, S. H., Lamb, B. K., and VanReken, T. M.: Development of a regional-scale pollen emission and transport modeling framework for investigating the impact of climate change on allergic airway disease, Biogeosciences, 11, 1461-1478, doi:10.5194/bg-11-1461-2014, 2014.
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:45679
Deposited By: Jason Perez
Deposited On:12 May 2014 20:08
Last Modified:10 Nov 2021 17:15

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