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Highlights
Past Highlights
June 2007
Multimedia Tools Development: Watershed Deposition Tool. Atmospheric Sciences Modeling Division (ASMD) has developed a Watershed Deposition Tool (WDT) for mapping the deposition estimates from a regional air quality model to watersheds. The WDT provides the linkage between airsheds and watersheds to estimate Total Maximum Daily Load (TMDL) and related nonpoint-source watershed analyses. This tool takes the gridded atmospheric deposition estimates from Community Multi-scale Air Quality (CMAQ) model and allocates them to 8-digit HUC’s (hydrologic cataloging units of rivers and streams) within a watershed, State or Region (see figure below). The WDT calculates the weighted average CMAQ atmospheric deposition (wet, dry, wet + dry) across a selected HUC or a set of selected HUC’s for a given scenario. The WDT can also calculate the average change in air deposition across a HUC between two different air deposition simulations. Calculations can be exported as CSV (comma delimited) files. Experienced GIS users can also export GIS Shape files of the CMAQ gridded outputs. The tool is designed to work under the Microsoft Windows operating system. Beta testing of the software has been completed and version 1.4.4 was released. The Watershed Deposition Tool can be downloaded from http://www.epa.gov/asmdnerl/Multimedia/depositionMapping.html. Questions or comments on the WDT should be directed to Donna Schwede donna.schwede@noaa.gov; 919-541-3255.
Ammonia Monitoring and Modeling. Matthew Jones of the Centre for Ecology and Hydrology, Edinburgh, Scotland has recently completed a brief post-doc appointment at ASMD. The focus of his research was the monitoring and modeling of leaf surface exchanges of NH3. He has worked with ASMD scientists to determine the best way to implement concentration-dependent cuticular resistances into CMAQ, the creation of a model to estimate these resistances and the validation of the model over a range of vegetation types. Dr. Jones worked with U.S. EPA scientists to install, test, and operate the Ammonia Measurement by ANular Denuder with on line Analyzer system (AMANDA) monitoring unit at field site near Lillington, NC. The unit provides higher temporal resolution, has a lower detection limit, and provides higher precision NH3 measurements than any other technique currently used in North America. Dr. Jones participated in a USDA funded intensive field campaign for NH3 deposition with scientists from ASMD, NOAA/ARL/Headquarters, the NOAA/ARL Atmospheric Turbulence and Diffusion Division, U.S. EPA National Risk Management and Assessment Laboratory and North Carolina State University. A publication will be developed in collaboration with ASMD scientists concerning the cuticular exchange model. Dr. Jones will continue the analysis of field data collected at the Lillington site and the collaboration with CMAQ model developers. (ellen.cooter@noaa.gov)
SCIENTIFIC ACCOMPLISHMENTS
Visualization Environment for Rich Data Interpretation (VERDI). Historically, the Package for Analysis and Visualization of Environmental data (PAVE) has been used to visualize the modeling results from the Community Multiscale Air Quality (CMAQ) model. PAVE is a Unix-based software system written in C and Motif. While CMAQ users have been satisfied with the functionality of PAVE, it is widely recognized that the PAVE technology is outdated. ASMD sponsored the development of a visualization system to provide an alternative to PAVE via an Interagency Agreement with Argonne National Laboratory (ANL). This software tool, Visualization Environment for Rich Data Interpretation (VERDI), is written in open-source JAVA and will run on Windows or Linux systems. The code for the tool will be made available to the public and community contributions for additional features will be encouraged. (donna.schwede@noaa.gov)
Analysis of Nitrogen Oxides (NOx) from Community Multiscale Air Quality (CMAQ) Model Simulations and Selected Measurement Sites. An effort has been underway to analyze concentrations of nitrogen oxides (NOx) during the 6:00 to 9:00 AM daily traffic rush hour period over 3‑month summer periods of 2002 and 2004. Of particular interest is to investigate the relative (percentage) change in NOx concentrations between the two summers that could be attributed to a change in NOx emissions from the mobile source sector in major urban areas of the northeastern United States. Therefore, hourly NOx measurements at select sites of the Photochemical Assessment Monitoring Station (PAMS) network situated downwind of different cities and hourly modeled NOx concentrations generated from Community Multiscale Air Quality (CMAQ) model simulations in the grid cells containing the PAMS sites for the same periods have been processed to compute 3‑hour average NOx concentrations for the daily morning high traffic period. Furthermore, running mean values are being computed by averaging these values over multiple days (e.g. 3 days or more) in an attempt to filter out short‑term impacts of synoptic-scale effects on the NOx concentrations. Then, average percentage change in NOx concentrations between the two summers can be derived to identify the extent of agreement between the measurements and the CMAQ model, whose surface NOx concentrations in urban areas are strongly governed by mobile source emissions. Results are expected to provide additional insight for a research effort investigating observed and model concentration changes in ozone between these summer periods as part of a dynamic evaluation effort. (james.godowitch@noaa.gov)
Spatio-Temporal Modeling of Total Nitrate. In collaboration with the North Carolina State University Department of Statistics, a statistical model has been developed to describe the spatial and temporal distribution of atmospheric total nitrate (gas-phase nitric acid plus fine particulate nitrate). The model uses 8 years of chemical and meteorological observations from 33 Clean Air Status and Trends Network (CASTNet) sites across the eastern United States to estimate the relative contributions of various formation and loss pathways during different seasons and locations. A manuscript describing the model application is nearing completion. (davis.jerry@epa.gov, prakash.bhave@noaa.gov)
North American Mercury Model Intercomparison Study (NAMMIS). The Community Multiscale Air Quality (CMAQ) modeling showed significant particulate mercury concentrations in air while the REMSAD and TEAM models did not. This difference between the CMAQ and REMSAD results could not be explained by differences in the chemistry of the two models, as they are quite similar in regard to the chemical reaction rates and product for mercury. Since all emissions and meteorology inputs were identical, it is speculated that some internal processes could be responsible for these differences in particulate mercury air concentration. Dry deposition has also been investigated. The REMSAD simulates relatively little dry deposition of mercury in any form. Investigation of this puzzling difference between the CMAQ and REMSAD results is continuing.
CMAQ model wet deposition patterns obtained using the three initial condition and boundary condition (IC/BC) data sets developed as part of the NAMMIS were compared to the lateral boundary values for mercury species concentrations from each IC/BC data set. A paper describing these results was submitted to the 29th NATO/SPS International Technical Meeting to be held in Aviero, Portugal in September 2007. (o.russell.bullock@noaa.gov)
On-line Photolysis Module in CMAQ. An on-line photolysis calculation module, developed by the University of North Carolina at Chapel Hill, was incorporated into CMAQ 4.6. In this approach, photolysis rates are computed on-line within the CMAQ calculations as opposed to the traditional approach in which clear-sky values were estimated at each grid point based on an input look-up table. A one-day test using the SAPRC99 chemical mechanism was successfully completed. Additional testing of the scheme for an extended period and comparisons of model predictions using the on-line and traditional approach are underway. (david.wong@noaa.gov)
CONFERENCES AND WORKSHOPS
Atmospheric Transmission Models Conference, Lexington, MA, June 12-14, 2007. John Streicher attended this conference. (john.streicher@noaa.gov)
EPA Science Advisory Board Integrated Nitrogen Committee Meeting, Washington, D.C., June 21, 2007. The SAB has formed the Integrated Nitrogen Research committee to develop information regarding EPA's nitrogen research and risk management programs. The information will provide the basis for an SAB report that will provide advice and recommendations regarding how the Agency may better integrate reactive nitrogen research and risk management strategies across environmental media and programs. Rohit Mathur gave a presentation on modeling the fate and transport of tropospheric nitrogen compounds at the invitation of the EPA Science Advisory Board Integrated Nitrogen Committee Meeting. (rohit.mathur@noaa.gov).
GEWEX Atmospheric Boundary Layer Study (GABLS) Workshop, Stockholm University, June 19-21, 2007. This meeting was attended by Jonathan Pleim. The first part of the workshop focused on further analysis and lessons learned from the GABLS2 experiment. This was a two-day period during the CASES99 field experiment that was simulated using ~20 different planetary boundary layer (PBL) single column models (SCMs). The Asymmetric Convective Model version 2 (ACM2) (Pleim 2007) was one of the participating models. The ACM2 results are published in a paper in JAMC (in press), and the summary and analysis of all model results will be described in a joint paper (lead by Gunilla Svensson). The second part of the workshop involved breakout groups and discussions about the next two experiments (GABLS3 and GABLS4). GABLS3 will be based on a selected “golden day” from the Cabauw, NL data, probably July 1-2, 2006. The thinking is that it will be easier to define the boundary layer forcing (geostrophic wind and surface fluxes) accurately for this case resulting in model simulations (both LES and SCMs) that can be better evaluated against the observations than was possible for the GABLS2 (CASES99) experiment. The GABLS3 experiment will happen quickly with analyzed results expect to be presented at next year’s BLT meeting in June 2008. The ACM2 will again be a participating model. A great deal has already been learned, particularly about modeling the stable boundary layer (SBL), from many of the most expert PBL scientists in the world. (jonathon.pleim@noaa.gov)
Air & Waste Management Association’s (AWMA) 100th Annual Conference and Exhibition, Pittsburgh, PA., June 26-29, 2007. Golam Sarwar gave a presentation entitled, “A comparison of Community Multiscale Air Quality (CMAQ) modeling system predictions with observations from the North East Oxidant and Particle Study. (golam.sarwar@epa.gov)
S.T. Rao participated in the panel discussions on climate change and air quality interactions at the AWMA meeting. (st.rao@noaa.gov)
David Mobley participated in a panel discussion on emission inventories. (mobley.david@epa.gov)
Eighth Weather Research and Forecasting (WRF) Users Workshop, June 11–14, 2007, Boulder, Colorado. Tanya Otte and Robert Gilliam attended this workshop. Mr. Gilliam presented his work toward implementing the Asymmetric Convective Model version 2 (ACM2) for the planetary boundary layer (PBL) and the Pleim-Xiu land-surface model (LSM) in WRF. He showed some promising early results that compared month-long WRF simulations using the new physics options with a similar configuration of the fifth-generation Pennsylvania State University/National Center for Atmospheric Research (PSU/NCAR) Mesoscale Model (MM5) and with a popular configuration of WRF that used a different PBL model and a different LSM. Ms. Otte was a coauthor with collaborators at PSU and NCAR on the four-dimensional data assimilation using analysis nudging that was implemented in the December 2006 release of WRF. Ms. Otte and Mr. Gilliam also attended several of the open WRF working group meetings that were held during the first day of the workshop.
The major news from the WRF Users Workshop is that NCAR plans to release a major change to the model in March 2008, to be named WRF version 3 (WRFv3). In addition to some new physics options, including the ACM2 and the Pleim-Xiu LSM, NCAR is planning to release a combined model with the two dynamical cores (WRF-Advanced Research WRF, and WRF-Nonhydrostatic Mesoscale Model), the variational analysis component (“WRF-Var”), the integrated online chemistry model (“WRF-Chem”), and an option to run WRF on a global domain (“global WRF”). (tanya.otte@noaa.gov, robert.gilliam@noaa.gov)
Seventh Ad Hoc Meteorological Modeling Meeting, Boulder, Colorado. June 14–15, 2007. Tanya Otte and Robert Gilliam attended this meeting, which involves all aspects of meteorological modeling that emphasize contributions toward air quality modeling research and applications. Mr. Gilliam presented his work toward implementing the Asymmetric Convective Model version 2 (ACM2) for the planetary boundary layer (PBL) and the Pleim-Xiu land-surface model (LSM) in WRF. Ms. Otte presented her research toward understanding the role of nudging in the meteorological model on the air quality model simulations. (tanya.otte@noaa.gov, robert.gilliam@noaa.gov)
PRESENTATIONS
Bhave, P. and A. Carlton. Modeling Carbonaceous Fine PM in CMAQ: Current Model Performance & Future Plans. Presented at the EPA Atmospheric Science Progress Review Meeting, EPA Campus, RTP, North Carolina, June 21, 2007.
Deng, A., D. R. Stauffer, J. Dudhia, T. Otte, and G. K. Hunter. Update on analysis nudging FDDA in WRF-ARW. Presented at the Eighth WRF Users Workshop, Boulder, Colorado, June13, 2007.
Gilliam, R., J. Pleim, and A. Xiu. Implementation of the Pleim-Xiu land surface model and Asymmetric Convective Model in WRF. Presented at the Eighth WRF Users Workshop, Boulder, Colorado, June 13, 2007.
Gilliam, R., J. Pleim, and A. Xiu. Implementation of the Pleim-Xiu land surface model and Asymmetric Convective Model in WRF. Presented at the Seventh Ad Hoc Meteorological Modeling Meeting, Boulder, Colorado, June 14, 2007.
Mathur, R. and R. Dennis, Modeling the fate and transport of tropospheric nitrogen compounds, Presented to the EPA Science Advisory Board Integrated Nitrogen Committee, Washington, D.C., June 21, 2007.
Mobley, J.D. Presented at the 100th Annual Air & Waste Management Association Conference, Pittsburgh, Pennsylvania, June 26, 2007.
Otte, T. L The impact of nudging in the meteorological model for retrospective CMAQ simulations. Presented at Seventh Ad Hoc Meteorological Modeling Meeting, Boulder, Colorado, June 15, 2007.
Rao, S.T. Interaction of climate change and air quality, Presented at the 100th Annual Air & Waste Management Association Conference, Pittsburgh, Pennsylvania, June 26, 2007.
VISITORS
Visitors to Fluid Modeling Facility. Twenty high school teachers from NOAA’s Earth System Science Institute for Educators (operated of North Carolina A&T State University’s Interdisciplinary Scientific Environmental Technology Cooperative Science Center) toured the Fluid Modeling Facility. The group viewed a demonstration of atmospheric dispersion of pollutants in a wind tunnel model of a near-roadway scenario. (david.heist@noaa.gov, steven.perry@noaa.gov)
PUBLICATIONS
Paper in Press
Kleindienst, T.E., M. Jaoui,M. Lewandowski, J.H. Offenberg, C.W. Lewis, P.V. Bhave, and E.O. Edney, Atmospheric Environment (2007). Estimates of the contributions of biogenic and anthropogenic hydrocarbons to secondary organic aerosol at a southeastern U.S. location. Accepted for Publication (June 25).
Submitted Paper
Luecken, D.J. “Technical challenges involved in implementation of VOC reactivity-based control of ozone,” submitted to Environmental Science and Technology, May 3, 2007.
Paper in NOAA Review
S.L. Napelenok, D.S. Cohan, M.T. Odman, S. Tonse, 2007. Extension and evaluation of sensitivity analysis capabilities in a photochemical model. To be submitted to Environmental Modeling & Software.
Paper in ASMD Review
Luecken, D.J., Phillips, S., Sarwar, G., Jang, C. Effects of using the CB05 vs. SAPRC99 vs. CB4 chemical mechanism on model predictions: ozone and gas-phase photochemical precursor concentrations.