Challenges in Simulating Bioaerosol Levels in the Mediterranean Atmosphere
摘要
Bioaerosols are primary biological aerosol particles released from the biosphere to the atmosphere, like bacteria, viruses, fungal spores, pollen, and fragments of organisms. Bioaerosols affect climate, acting as cloud condensation nuclei or ice nuclei, and human health, acting as allergens, while they carry nutrients to the ecosystems. Bioaerosol emissions depend on meteorological conditions (temperature, wind speed, humidity and precipitation), and ecosystem type. As a result, their emissions show seasonal and daily variation. In this study, we first review and compare the published parameterisations of bioaerosol emissions that have been derived from observations and are proposed for use in numerical air quality and chemistry-climate models. Then, we use WRF-Chem, a regional numerical weather prediction model coupled with chemistry, and integrate such parameterisations to simulate the emissions, transport and deposition of bacteria, fungal spores and pollen in the Mediterranean atmosphere. The model is evaluated by comparing meteorological variables, gas and aerosol concentrations simulated by WRF-Chem with near-surface observations. The simulated 3-D distributions of the three main types of bioaerosols are presented for July, and their levels are compared with previous studies over land and oceanic regions.