Biological and Environmental Research - Earth and Environmental System Sciences
Earth and Environmental System Modeling
09 April 2014

Regional Modeling of Dust Mass Balance and Radiative Forcing over East Asia using WRF-Chem


Dust affects climate in many ways. It can impact the radiation budget, alter cloud properties, change the surface reflectivity of snow and glaciers, and influence the ocean’s ability to absorb CO2 and nutrients. Dust also has a large impact on human health and air quality and visibility. Researchers, including DOE scientists at Pacific Northwest National Laboratory, used the Weather Research and Forecasting model with Chemistry (WRF-Chem) to investigate the seasonal and inter-annual variations of mineral dust over East Asia during 2007–2011. The research focused on the dust mass balance and its direct radiative forcing, plus the dust lifecycle contributions from various physical processes (e.g. dust emission, transport, and dry and wet deposition) over seven sub-regions including desert dust sources in East Asia. They found that WRF-Chem reasonably reproduces not only the column variability but also the vertical profile and size distribution of mineral dust over and near the dust source regions. The research used satellite and in situ measurements to evaluate the simulations over and near major dust source regions. The observations over the dust source regions isolated from the anthropogenic impact are needed in order to better evaluate the simulated dust optical properties. In terms of size distribution, the simulations capture the seasonal variations of the observed size distributions but overestimate the fine and underestimate the coarse dust particles. The ability of WRF-Chem to capture the measured features of dust optical and radiative properties and dust mass balance over East Asian provides confidence for future investigation of East Asia dust impact on regional or global climate.