2011 - Cooperative Institute for Research in Environmental Sciences ...

extent (i.e., chemical age) of that chemistry and possible fates
(e.g., secondary organic aerosol formation or growth) of the
species.
3) Measurements from Atlantis demonstrated that sulfur
dioxide emissions from commercial marine vessels were
within regulatory limits, which was of considerable interest
to the California Air Resources Board (CARB).
Product: Results from CIRES research conducted during
the 2010 CalNex field mission were presented during a
workshop at the CARB headquarters during May 2011. The
agenda and links to the presentations are available at http://
www.arb.ca.gov/research/calnex2010/calnex2010.htm.
Milestone 3. Co-deploy airborne ozone and Doppler wind
lidars during the 2010 CalNex air quality study to investigate
transport processes of air pollutants. Impact: The
combination of airborne ozone and Doppler lidars will
allow us to measure simultaneously ozone concentration
and wind speed and direction at high resolution and thus
enable us to characterize and quantify transport processes
of air pollutants in California on local and regional
scales. The information will be scientific input for air quality
decision makers in the state of California.
During the CalNex experiment from May through July
2010, we co-deployed NOAA’s airborne Tunable Optical
Profile for Aerosol and Ozone (TOPAZ) lidar and the
University of Leeds scanning Doppler wind lidar on a Twin
Otter aircraft. We flew 46 missions over the state of California,
totaling approximately 200 flight hours and focusing
primarily on the Los Angeles Basin and Sacramento areas.
The downward-looking lidars provided highly resolved
measurements of ozone concentration, aerosol backscatter
and wind speed and direction in the boundary layer and
lower free troposphere. We have used these data to characterize
transport of pollutants on local, regional and continental
scales for a number of cases. In particular, we have
identified important ozone transport pathways between air
basins in southern California. This included characterizing
the role of flow patterns in complex terrain, such as gap
flows and orographic lifting and venting along mountain
slopes, in redistributing ozone in southern California. We
have also consistently observed layers of high ozone concentrations
at a few kilometers altitude above ground level.
While some of these layers are caused by lofting of locally
produced ozone, trajectory analysis revealed that in a num-
O3 distribution over the Los Angeles Basin and Mojave Desert measured
with NOAA’s TOPAZ ozone lidar on July 2, 2010.
ber of cases, the ozone aloft was associated with transport
of pollutants from Asia or downward transport of ozone
from the stratosphere during stratospheric intrusion events.
We have presented these results at the 2010 American Geophysical
Union Fall Meeting and at a CalNex data analysis
workshop in spring 2011, during which we communicated
our findings to scientists and regulators from CARB.
GSD-02RegionalAirQualityPrediction
FEDERAL LEAD: GEORG GRELL
CIRES LEAD: STEVEN PECKMAN
NOAA Goal 3: Weather and Water
Project Goal: Design and evaluate new approaches for improving
air-quality prediction.
Milestone 1. Test and evaluate the global FIM-Chem (Flowfollowing
finite-volume Icosahedral Model) currently
under development in ESRL and containing chemistry
modules from the GOCART (Goddard Chemistry Aerosol
Radiation and Transport) model, together with global
wildfire definition and global anthropogenic emissions
data. Run FIM-Chem in real time at the highest affordable
resolution to predict multi-day global transport of aerosol
and impact on weather forecasts.
The GOCART aerosol modules have been successfully included
into FIM, and evaluation continues to be performed.
An emissions processor from the Weather Research and
Forecast–Chemistry model (WRF–Chem) was modified for
use with the FIM to provide global wildfire emissions and
anthropogenic emissions. Additionally, volcanic ash from
volcanic eruptions was included both in the FIM and the
emissions preprocessor. The resulting “FIM-Chem-ash” was
run in real time twice a day following the major volcanic
eruption in Iceland in April, and results from the forecasts
are being evaluated.
Milestone 2. Continue to coordinate worldwide development
of WRF-Chem (Weather Research and Forecasting
Model) as an air-quality prediction tool and support the
growing user community.
CIRES’ leadership role in the development of this modeling
system continues. WRF-Chem version 3.3 was released
in April 2011 with many new additions, including additional
coupling between chemistry and
physics modules as well as new additions
to chemical mechanisms (provided
by the National Center for Atmospheric
Research, the Pacific Northwest National
Laboratory and the Earth System
Research Laboratory’s Chemical Sciences
Division). In addition, significant
improvements have been made to the
data input/output (I/O) streams, which
should enhance the overall performance
of WRF-Chem.
CIRES Annual Report 2011 129