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

Abstract

Abstract. 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 O 3 , PM 2.5 , 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.

Separation of the optical and mass features of particle components in different aerosol mixtures by using POLIPHON retrievals in synergy with continuous polarized Micro-Pulse Lidar (P-MPL) measurements

“…Final-corrected P , P || and P ⊥ are obtained using the procedure described in Campbell et al (2002) and Welton and Campbell (2002). The linear volume depolarization ratio, δ V , in a classical sense (Sassen, 1991), can be defined as…”

“…Table 3 shows the AERONET parameters involved in the extinction-to-mass conversion (VC c,f , τ c,f ) at selected times for each aerosol case together with those typical particle densities Pd for each aerosol component. In particular, Pd values assumed for each type of aerosols are 2.60 g cm −3 for dust (Ansmann et al, 2012), 1.30 g cm −3 for smoke (Reid et al, 2005) and 0.92 g cm −3 for pollen (Platanus) particles (Jackson and Lyford, 1999;Zhang et al, 2014). For the other components, the particle density is obtained from the OPAC database .…”

A High-resolution Numerical Simulation and Evaluation of Oak Pollen Dispersion Using the CMAQ-pollen Model

“…최근에는 제한된 꽃가루 모니터링자료와 통계 모델의 한계를 보완하기 위해 꽃가루 수치모델링 방법 이 구체적으로 제안되었고 (Efstathiou et al, 2011;D'Amato et al, 2007;Sofiev et al, 2006) Zhang et al, 2013). 하지만 성공적인 수치모델링에 있어 꽃가루 배 출량 추정의 불확실성, 물리적 특성과 침적과정의 정 확한 고려, 식생입력자료의 한계 극복을 위해서 지속 적인 연구가 필요할 것이다.…”

Ragweed pollen production and dispersion modelling within a regional climate system, calibration and application over Europe

“…Presently a number of regional models, mostly designed for air quality prevision, incorporate release and dispersion dynamics of pollen (Helbig et al, 2004;Sofiev et al, 2006Sofiev et al, , 2013Skjøth, 2009;Efstathiou et al, 2011;Zink et al, 2012;Prank et al, 2013;Zhang et al, 2014). Methods for producing ragweed pollen emission suitable for input to regional scale models have been developed in recent studies (Skjøth et al, 2010;Šikoparija et al, 2012;Chapman et al, 2014).…”