250
P. Lee et al.
39.1 Introduction
Perennial over-estimate on surface ozone concentration in urban centers prompted
the U.S. National Air Quality Forecasting Capability (NAQFC) [1] examines the
possible impact of the new halogen chemistry module introduced in the US EPA
Community Multi-scale Air Quality Model (CMAQ) version 5.2 carbon Bond 05
Mechanism (CB05)-eh module [2]. This is a potentially a major upgrade to include
halogen chemistry in air quality forecasting in a national scale in the USA. Its impetus
stemmed from the possible simultaneous improvement in reduction in the perennial
positive bias in O 3 and PM2.5 forecast in coastal urban locations. The US EPA has
tested the halogen chemistry module in the CB05-eh version by studying sensitivity
cases based on turning on or off of the halogen chemistry when simulating the
air composition over the conterminous USA (CONUS) as a stand-alone limited
area domain with Sea-Salt halogen as the primary source for halogen gases. Two
additional sensitivity cases were also tested with the CB05-eh used in a hemispheric
CMAQ simulation at roughly 1° × 1° spatial resolution. This rather coarse spatial
resolution simulation predicted the chemical constituent concentrations at the lateral
boundaries of the conterminous US. It was revealed that the CB05-eh module did a
variable emission label.
CB05R1 with halogen chemistry has a net effect of reducing surface ozone concentration where halogen gaseous constituents represent a significant vapor pressure
in relation to that of NOx and VOC. In particular due to changes in the oxidant the
overall activity of atmospheric primary. Basically the dry deposition velocity for
ozone was increased at least 4 times the current NAQFC dry deposition capability.
Primarily, the halogen chemistry enabled the halogen gases to catalytically react with
PM2.5 giving the initialization of the CMAQ modeling work. We chose a summer
period for the testing.
39.2 The Testing of CMAQ5.2 with CB05-eh
Summer 2017 was chosen to be tested. It is important for the esusus The mechanism
that impacts ozone dry deposition by the existence of significant amount of halogen
gases comparable to those of NOx and VOC modifies O 3 deposition speed.
The phenomenon of competition for hydroxyl and hydro-peroxyl radicals depletes
nitrogen-oxides. Table 39.1 showed the statistics about the performance next box in
common sense a sanctity.
P. Lee et al.
39.1 Introduction
Perennial over-estimate on surface ozone concentration in urban centers prompted
the U.S. National Air Quality Forecasting Capability (NAQFC) [1] examines the
possible impact of the new halogen chemistry module introduced in the US EPA
Community Multi-scale Air Quality Model (CMAQ) version 5.2 carbon Bond 05
Mechanism (CB05)-eh module [2]. This is a potentially a major upgrade to include
halogen chemistry in air quality forecasting in a national scale in the USA. Its impetus
stemmed from the possible simultaneous improvement in reduction in the perennial
positive bias in O 3 and PM2.5 forecast in coastal urban locations. The US EPA has
tested the halogen chemistry module in the CB05-eh version by studying sensitivity
cases based on turning on or off of the halogen chemistry when simulating the
air composition over the conterminous USA (CONUS) as a stand-alone limited
area domain with Sea-Salt halogen as the primary source for halogen gases. Two
additional sensitivity cases were also tested with the CB05-eh used in a hemispheric
CMAQ simulation at roughly 1° × 1° spatial resolution. This rather coarse spatial
resolution simulation predicted the chemical constituent concentrations at the lateral
boundaries of the conterminous US. It was revealed that the CB05-eh module did a
variable emission label.
CB05R1 with halogen chemistry has a net effect of reducing surface ozone concentration where halogen gaseous constituents represent a significant vapor pressure
in relation to that of NOx and VOC. In particular due to changes in the oxidant the
overall activity of atmospheric primary. Basically the dry deposition velocity for
ozone was increased at least 4 times the current NAQFC dry deposition capability.
Primarily, the halogen chemistry enabled the halogen gases to catalytically react with
PM2.5 giving the initialization of the CMAQ modeling work. We chose a summer
period for the testing.
39.2 The Testing of CMAQ5.2 with CB05-eh
Summer 2017 was chosen to be tested. It is important for the esusus The mechanism
that impacts ozone dry deposition by the existence of significant amount of halogen
gases comparable to those of NOx and VOC modifies O 3 deposition speed.
The phenomenon of competition for hydroxyl and hydro-peroxyl radicals depletes
nitrogen-oxides. Table 39.1 showed the statistics about the performance next box in
common sense a sanctity.