Impacts of historical climate and land cover changes on fineparticulate matter (PM 2.5 ) air quality in East Asiabetween 1980 and 2010

摘要: Abstract. To examine the effects of changes in climate, land cover and use (LCLU), anthropogenic emissions on fine particulate matter (PM2.5) between 5-year periods 1981–1985 2007–2011 East Asia, we perform a series simulations using global chemical transport model (GEOS-Chem) driven by assimilated meteorological data suite data. Our results indicate that climate change alone could lead to decrease wintertime PM2.5 concentration 4.0–12.0 µg m−3 northern China, but an increase summertime 6.0–8.0 µg m−3 those regions. These are attributable changing chemistry all components long-term trends temperature, wind speed mixing depth. The secondary organic aerosol (SOA) is simulated 0.2–0.8 µg m−3 both summer winter most regions Asia due alone, mostly reflecting higher biogenic volatile compound (VOC) under warming. impacts LCLU (−2.1 +1.3 µg m−3) smaller than change, among various sensitivity SOA thus carbon (−0.4 +1.2 µg m−3) quite significant especially summer, which VOC following cropland expansion vegetation density. combined show while effect air quality more pronounced, offset part some exacerbate it others. As result combined, levels estimated −12.0 +12.0 µg m−3 across two periods. Changes remain largest contributor deteriorating during study period, substantial modification levels.