Grantee Research Project Results
2007 Progress Report: Investigation of the Interactions between Climate Change, Biomass, Forest Fires, and Air Quality with an Integrated Modeling Approach
EPA Grant Number: R832277Title: Investigation of the Interactions between Climate Change, Biomass, Forest Fires, and Air Quality with an Integrated Modeling Approach
Investigators: Shankar, Uma , Hanna, Adel , Fox, Douglas G. , Binkowski, Francis S. , Xiu, Aijun , Holland, Andy , Seppanen, Catherine , Vukovich, Jeff , McNulty, Steve
Institution: University of North Carolina at Chapel Hill , USDA
EPA Project Officer: Chung, Serena
Project Period: March 13, 2005 through March 12, 2008 (Extended to March 12, 2009)
Project Period Covered by this Report: March 13, 2007 through March 12,2008
Project Amount: $726,566
RFA: Fire, Climate, and Air Quality (2004) RFA Text | Recipients Lists
Research Category: Air Quality and Air Toxics , Air , Climate Change
Objective:
Forest fires not only change landscapes and destroy property but also emit trace gases and aerosols (e.g. CO, CH4, NOx, and black carbon) that affect regional and global air quality, with consequences to human health, as well as to climate through their interactions with solar radiation. These impacts can be felt over long distances due to the long range transport of these pollutants both as primarily emitted species, and as precursors for other pollutants formed in the atmosphere through photochemical reactions. Recently, the increased frequency of large fires in the U.S. has been thought to be associated with short-term changes in climate variables such as precipitation and temperature that have exacerbated the conditions for fire occurrence. Thus the overall goal of this research is to assess the impact of climate change and variability on biomass and forest fires, the impact of the evolving emissions from forest fires on ozone and PM air quality, and the regional climate response to air quality changes in the Southern U.S using an integrated modeling system. Integration of some of these feedbacks in the model simulations will allow a more realistic representation of future-year emissions from both biogenic and fire sources, and their impact on air quality. This would facilitate assessment of the air quality and ecosystem benefits of various fire management scenarios that are currently not included in most emissions control evaluations.
The primary objectives in support of the overall goal are:
1. To investigate the impacts of climate change on vegetative cover and fuel characteristics, the consequences for fire frequency and intensity, and feedbacks to biomass load and biogenic emissions under managed and wildfire scenarios.
2. To examine changes in regional air quality due to the evolution of anthropogenic and biogenic emissions in response to various fire scenarios.
3. To investigate the feedback of the air quality changes to regional climate variables.
Progress Summary:
The project is a collaboration between researchers at UNC, Dr. Douglas Fox, a private consultant and fire modeling expert, and researchers at the USFS Southern Global Change Program (SGCP), led by Dr. Steven McNulty. Within the last year, Dr. Donald McKenzie from the USFS Pacific Wildland Fire Sciences Laboratory, and Dr. Jeffrey Prestemon from the USFS Southern Research Station have been active consultants on the project to provide guidance and assist in the modeling of future-year fires, and accounting for fire ignitions that are human-induced, as frequently occurs in the Southeastern U.S. (Mercer and Prestemon, 2005). The modeling system for the studies listed in the project objectives is shown in Figure 1. Research in the third year of the project focused on three key areas of development and implementation within this system: the forest growth model, PnET (Aber et al., 1996), the fire emissions model, BlueSky-EM (Sestak et al., 2002), and developing data linkages to the Fire Scenario Builder (FSB), a stochastic model for predicting fire area burned, developed by Dr. McKenzie and co-workers (McKenzie et al., 2006). The project is a collaborative effort between researchers at UNC, Dr. Douglas Fox, a private consultant and fire modeling expert, and researchers at the USFS Southern Global Change Program (SGCP), led by Dr. Steven McNulty. Within the last year, Dr. Donald McKenzie from the USFS Pacific Wildland Fire Sciences Laboratory, and Dr. Jeffrey Prestemon from the USFS Southern Research Station have been active consultants on the project to provide guidance and assist in the modeling of future-year fires, and accounting for fire ignitions that are human-induced, as frequently occurs in the Southeastern U.S. (Mercer and Prestemon, 2005). The modeling system for the studies listed in the project objectives is shown in Figure 1. In the third year of the project the team continued development and implementation tasks begun in the prior years in three key areas of this system, namely, the three-way linkages of the forest growth model, PnET (Aber et al., 1996) applied over the Southeastern U.S., the fire emissions model, BlueSky-EM (Sestak et al., 2002), and the Fire Scenario Builder (FSB), a stochastic model for predicting fire area burned, developed by Dr. McKenzie and co-workers (McKenzie et al., 2006).
Figure 1. Schematic of the modeling system. Modifications to the original concept include replacement of the BEIS3 biogenic emissions model with MEGAN, developed by NCAR.
3.1. Forest Process Modeling
In the third year of the project there was a thorough re-evaluation of the daily PnET version investigated in the first year for application to a large region such as the Southeast. Several vegetation and site-specific inputs are required to simulate plot-level forest growth besides climate parameters (monthly mean minimum and maximum temperature, monthly precipitation and photosynthetically active radiation); plot-level data are then expanded to the county level using expansion factors compiled by the USFS for the various vegetation types. Input data collected for the base year (2002) for the 13 states shown in Figure 2 from the Forest Inventory Analysis (FIA) databases in Knoxville, TN, were quality assured by comparing the output against SGCP’s archived outputs for reasonable performance. The live biomass predicted for the base year and the forest fuel load data from the FIA were examined to develop correlations between the two for the purpose of projecting future-year fuel loads from PnET predictions of future live biomass.
Figure 2. Modeling domain for the PnET forest growth model application
3.2. Fire Emissions Modeling
In this project period we completed the work on providing the data linkages from the forest growth model to the BlueSky-EM smoke emissions model to generate future-year fuel loads for the BlueSky fire emissions predictions. Correlations based upon a multivariate regression analysis of the FIA plot data of live biomass vs. dead wood in the 13 states shown in Figure 2, included temperature, precipitation and total mean solar radiation reaching the ground as variables for the regression. However, the correlations were very poor, and thus the decision was made to use only canopy fuel in the projections, and assume a percent of canopy biomass to be the canopy fuel. Estimates of 10-hr and 100-hr fuel were made using this approach for use in fire emissions projection. The fuel loads of remaining fuel classes were assumed constant in future years.
Work began to incorporate both lightning and human ignition probabilities for the nested domain over the Eastern U.S. shown in Figure 4. This entails the use of gridded projection factors being developed by Drs. Prestemon and Mercer from the population and economics growth database provided by Woods & Poole Economics, Inc. for future years, and from fire activity statistics obtained for the base year (2002) from the National Fire and Aviation Management Web Applications database (see http://fam.nwcg.gov/fam-web/ ).
3.3. Air Quality Modeling Activities
Under a previous STAR grant, UNC investigators have developed an air quality modeling system with integrated meteorology and chemistry (METCHEM) as a modular, physically and numerically consistent, fully integrated regional-scale atmospheric dynamics and chemistry modeling system. It is based on further development and refinement of three existing models: the MM5; the Multiscale Air Quality Simulation Platform (MAQSIP) (Mathur et al., 2005); and the SMOKE modeling system. The integrated modeling framework enables investigation of the feedbacks of radiatively important trace species to the atmospheric dynamics. METCHEM applications over the Eastern U.S. have been able to capture the increase in optical depth due to the presence of aerosols, resulting in a reduction in the shortwave radiation reaching the ground, and consequently, in the surface temperature and PBL height.
In Year 3 work began on projecting anthropogenic emissions for the non-point sources from the base year to the future year using projection methods developed by the EPA. There was also a slight change in the future years selected for the modeling to include 2020 rather than 2015, in addition to 2030 and 2050. Work is underway for processing emissions from non-fire sources for the Southeastern U.S. at 12-km resolution; these will be merged with fire emissions for input to METCHEM. We also ran METCHEM over the CONUS domain for test periods in the summer and winter of 2002 and compared the results against observations from the IMPROVE and the EPA Speciation Trends Network (STN). We began diagnosing the over predictions in ammonium and nitrate through a comparison of the RPO inventory data used in these simulations against the EPA NEI 2002, and the meteorological model configuration.
Figure 4. METCHEM simulation domains; domain D02 will include the impacts of PnET-predicted biomass changes on the fire emissions inputs.
Future Activities:
In the no-cost extension period of the project, the main objective will be completion of the remaining modeling tasks to examine the fire emissions impacts on air quality under various fire scenarios (wild fires only vs. National Fire Management Plan). As stated in the objectives, there has been a change to the scope of the project regarding the changes in the biogenic emissions due to fire scar, due to the difficulty of obtaining information to map the PnET vegetation types, developed at the plot level to the BELD3 1-km resolution land cover data. The project tasks will focus on the following areas:· Complete the daily area burned estimates with the modified FSB from projected annual area burned estimates.
· Complete the BlueSky simulations with the projected fires in 2020, 2030 and 2050, and merge with projected anthropogenic emissions.
· Complete corrections to the METCHEM configurations, and nest down to the southeastern U.S. at 12-km for two seasonally representative 6-week periods in 2002.
· Complete future-year (2020, 2030 and 2050) METCHEM simulations for the wild fire season and examine trends of aerosol properties.
· Prepare final project report.
References:
Aber, J. D., S. V. Ollinger, and C. T. Driscoll, 1997: Modeling nitrogen deposition in forest ecosystems in response to land use and atmospheric deposition, Ecol. Modell., 101, 61-78. http://www.pnet.sr.unh.edu/onlinepubs/EcoMod-v101-p61.html
Mathur, R., U. Shankar, A. F. Hanna, M. T. Odman, et al., 2005: Multiscale Air Quality Simulation Platform (MAQSIP): Initial applications and performance for tropospheric ozone and particulate matter, J. Geophys. Res., 110, D13308, doi:10.1029/2004JD004918.
McKenzie, D. .M., S. M. O’Neill, N. K. Larkin, and R. A. Norheim, 2006: Integrating models to predict regional haze from wildland fire, Ecol. Modell., 199, doi:10.1016/j.ecolmodel.2006.05.029.
Mercer, D. E., and J. P. Prestemon, 2005: Comparing production function models for wildfire risk analysis in the wildland–urban interface, Forest Policy Economics, 7, 782-795.
Sestak, M., O’Neill, S., Ferguson, S., Ching, J., and D. Fox, 2002: Integration of Wildfire Emissions into Models-3/CMAQ with the prototypes Community Smoke Emissions Modeling System (CSEM) and BlueSky. In Proceedings of the Second Annual CMAS Workshop, October 21-23, 2002, Research Triangle Park, NC. http://www.cmascenter.org/conference/2002/session5/fox_abstract.pdf
Journal Articles:
No journal articles submitted with this report: View all 21 publications for this projectSupplemental Keywords:
Forest biomass, fire emissions, land cover changes, air quality climate feedbacks., RFA, Air, Scientific Discipline, Ecosystem Protection/Environmental Exposure & Risk, Ecological Risk Assessment, Chemistry, Atmosphere, Monitoring/Modeling, Air Pollution Effects, climate change, Environmental Monitoring, air quality, global ciruclation model, Global Climate Change, climate model, atmospheric chemistry, coastal ecosystems, global change, ecological models, terrestial ecosystem model, Community Smoke Emissions Model, climate variability, environmental measurement, climate models, forest resources, environmental stress, air quality model, meteorology, biomass, ozone depletion, climatic influenceRelevant Websites:
The project website is http://www.ie.unc.edu/cempd/projects/FIRE/.
Progress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.