WP3: Atmospheric Impacts and Effects

Emissions of reactive nitrogen to the atmosphere, including both NOx and NH3, have important contributions to the formation of PM2.5 air pollution in urban atmosphere over the world. The North China Plain, particularly the Beijing−Tianjin−Hebei (BTH) megacities, has been experiencing heavy PM2.5 air pollution in recent years, causing public concerns on human health.

In this work package, we will investigate the impacts of different mitigation pathways for nitrogen management in the urban agricultural activities on PM2.5 air pollution in the project test areas (greater Beijing as well as Europe), and their surround regions.

• Based on different scenarios of urban agriculture and considering different mitigation pathways of nitrogen management, the amount of ammonia emitting to the atmosphere from agricultural activities, including fertilizer applications and livestock waste will be estimated.
• Results of PM2.5 concentrations at fine resolution from two atmospheric chemistry models (GEOS-Chem model and WRF-Chem) will be evaluated using present-day emission inventory. GEOS-Chem can cover both China and Europe at a horizontal resolution of 1/4° × 5/16° (∼25 km), and WRF-Chem runs at horizontal resolutions of 36 km and 4 km over the BTH region.
• The ammonia emission estimates from the first phase of the work package will be implemented to both atmospheric chemistry models, and their effect on the PM2.5 concentrations in the urban atmosphere will be quantified.