Environmental Engineering Reference
In-Depth Information
5.4 Development of NCEP Global Aerosol Forecasting
System: An Overview and It Applications for
Improving Weather and Air Quality Forecasts
Sarah Lu
1
, Ho-Chun Huang
1
, Yu-Tai Hou
1
, Youhua Tang
1
, Jeff McQueen
1
,
Arlindo da Silva
2
, Mian Chin
2
, Everette Joseph
3
, and William Stockwell
3
1
NOAA/NWS/NCEP Environmental Modeling Center, Camp Springs, MD 20746, USA
2
NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
3
Howard University, Washington, DC 20059, USA
Abstract
The National Centers for Environmental Prediction (NCEP) Environ-
mental Modeling Center (EMC) is developing global aerosol forecasting and
assimilation capabilities to improve the treatment of radiation feedback in the
numerical weather predictions and to provide aerosols boundary conditions for
the regional air quality forecast system. This paper present two impact studies:
(1) the impact of lateral aerosol boundary conditions on aerosol air quality fore-
casts, and (2) the impact of improved aerosol treatment on medium range weather
forecasts.
Keywords
Aerosols, lateral boundary condition, aerosol-radiation feedback
1. Introduction
The NCEP Global Forecast System/Global Data Analysis System (GFS/GDAS) is
the decision support system used by NOAA for medium range weather predictions.
The forecast model, GFS, is a global spectral model with the state-of-the-science
physical parameterizations (Moorthi et al., 2001) and the analysis system, GDAS,
uses the Gridpoint Statistical Interpolation (GSI) scheme (Wu et al., 2002).
Climatology-derived aerosol distributions are currently used in the GFS radiation
module and background aerosol conditions are assumed in the GSI radiative transfer
scheme. Consequently the effect of aerosols on radition, clouds, and convection are
poorly represented in the GFS and the effects of aerosol attenuation on radiance
are yet to be quantified in the GSI.
The NCEP EMC is developing global aerosol forecasting and assimilation
capabilities in GFS/GSI by incorporating prognostic aerosols (the GOCART
model, Chin et al., 2002) in GFS and assimilating global aerosol information in
GSI. This NOAA/NCEP-NASA/GSFC-Howard University collaborative project
