NOAA GFDL - Geophysical Fluid Dynamics LaboratoryGFDL - Geophysical Fluid Dynamics Laboratory

Export of Asian pollution to the western Pacific

May 6th, 2010

Key Findings

  • Provides the first estimate of the influence of European PAN on local ozone budgets over East Asia in spring. The PAN driving ozone production can contribute up to 50% of the total ozone response in subsiding plumes at mountain observatories.
  • Highlights the important roles of rapid convective transport, orographic forcing, urban photochemistry and heterogeneous boundary layer processes in controlling intercontinental transport; these processes are well resolved in the large-scale models.
  • Suggests a real need for high-resolution model studies of global pollution transport.

Quantifying pollution inflow and outflow over East Asia in spring with regional and global models by Meiyun Lin(Princeton U), Tracey Holloway (U Wisconsin), Greg Carmichael (U Iowa), and Arlene Fiore explores two high-resolution atmospheric chemistry models to examine the role of mesoscale versus synoptic scale processes in controlling pollution export from East Asia. Their results indicate the importance of rapid pollution venting through deep convection that develops along the leading edge of frontal system convergence bands. This transport mechanism is well captured in a high-resolution climate-chemistry model (WRF-Chem), but not adequately resolved in either of two coarse-resolution global models compared with aircraft observations of pollution lofting, suggesting a real need for high-resolution model studies of global pollution transport.

Figure Caption: This figure shows observed and predicted vertical distributions of trace gases along a NASA DC-8 flight track during the TRACE-P campaign (Feb-Apr.2001). The black lines in the upper (global MOZART model) and middle (regional WRF-Chem model) panels denote the flight path.
Figure Caption: This figure shows observed and predicted vertical distributions of trace gases along a NASA DC-8 flight track during the TRACE-P campaign (Feb-Apr.2001). The black lines in the upper (global MOZART model) and middle (regional WRF-Chem model) panels denote the flight path.