Christine Wiedinmyer

General Information

ACD - TIIMES
Scientist II
BEACHON & BGS

Contact Information:
PO Box 3000, Boulder, CO 80307-3000
Office: FL0-3154
Telephone: 303-497-1414
Email: christin@ucar.edu
Home Page - Vita

Research Focus FY08:

Emissions of Particles & Gases from the Biosphere

Wiedinmyer’s research focuses on the emissions of particles and gases from the biosphere, and how these impact atmospheric processes, specifically chemistry. In the recent past, she has led the development of a fire emissions model for North America for use by atmospheric modelers (Wiedinmyer et al., 2006) and contributed to the development of a new biogenic emissions model, Model of Emissions of Gases and Aerosols from Nature, MEGAN (Guenther et al., 2006). These emission estimates have been used with other models to evaluate the impact of these emissions on chemistry and meteorological processes.

In the past fiscal year, several advances have been made in terms of the ability to model emissions, chemistry and meteorology. Implementation of sesquiterpene emissions within MEGAN and chemical transport models has been completed, and the amount of secondary organic aerosol formed from these compounds in the US has been estimated (Sakulyanontvittaya et al., 2008; Sakulyanontvittaya et al., in press). The results of these studies are shown in Figure 1.

MEGAN has been included within the WRF-chem framework, so that biogenic emissions can be simulated online with atmospheric chemistry and meteorology. Preliminary studies have been performed to evaluate the direct impact of aerosols on clouds, and further, the impact on biogenic emissions (S. Chung (WSU), J. Fast (PNNL), and C. Wiedinmyer).  Several modeling studies have been completed to investigate the impact of climate and land cover/land use change on future air quality. With X. Jiang (University of Texas) and F. Chen (RAL), the impact of future land cover change and climate on local meteorology and chemistry was investigated for Houston Texas with the use of the WRF-chem model (Jiang et al., in press). Investigations of future climate and land cover changes were performed for the continental US with collaborators from Washington State University, University of Washington and the US Forest Service (Chen et al., Atmospheric Chemistry and Physics Discussions, 2008; Avise et al., Atmospheric Chemistry and Physics Discussions, 2008).

 

Emissions of Mercury & CO2 from Fires

Emissions of mercury (Wiedinmyer and Friedli, 2007) and CO2 (Wiedinmyer and Neff, 2007) from fires across the US have been estimated using the North American Fire Emissions Model.  These emission estimates are addressed in terms of the policy implications of these emissions.  An inter-comparison of fire emission estimates for the contiguous U.S. was completed with colleagues from other national agencies (Al-Saadi, Journal of Applied Remote Sensing, 2008). The results of this project highlighted the uncertainty associated with fire emission estimates and the need to better constrain the models.

The Storm Peak Aerosol and Clouds Characterization Study 2008 (SPACCS08)

Wiedinmyer led an exploratory study at the Storm Peak Laboratory in April 2008. The Storm Peak Aerosol and Cloud Characterization Study (SPACCS2008) took place from March 23 through April 15, 2008 at the SPL (located at 10,200 ft ASL in Steamboat Springs, CO). Collaborators from over 10 different universities and organizations (including several graduate students) participated in an effort to characterize the biological and chemical composition of the ambient air, cloud water, and snow at the site. Analysis of the data is on-going.

News Release & Background Information:
- U.S. Fires Release Large Amounts of Carbon Dioxide, New Study Shows
- Scientists Estimate Mercury Emissions from U.S. Fires; West Coast and Southeastern States are Major Emitters
- New Approaches to Understanding Wildfires
- NCAR Scientists Available to Discuss Wildfire Impacts and Behavior : Wildfire Animation
- Background: Wildfires
- Wildfire Research at MMM

In the News:
- Wildfires Spew Carbon, Re-Growth Absorbs It - (Discovery News by Larry O'Hanlon, 1 November 2007)
- California wildfires unleash CO2 (Environment Correspondent by Deborah Zabarenko, Reuters 1 November 2007)
- US Fires Release Large Amounts Of Carbon Dioxide (Science Daily, 1 November 2007)
- Wildfire smoke a culprit in mercury's toxic spread (The Denver Post by Steve Lipsher, 19 October 2007)
- Scientists estimate state-by-state mercury emissions from US fires (Science Codex, 17 October 2007)
- It Droppeth as the Gentle Rain (Colorado Confidential by Dan Whipple, 17 October 2007)
- Addional News Articles: links

 

Impact of Forest Mortality from the Mountain Pine Beetle

The beginning of a project investigating the impact of forest mortality in the western U.S. from the mountain pine beetle has begun. Work with F. Chen, M. Tewari, and M. Barlage has begun to determine the sensitivity of meteorological predictions to large forest mortality with the use of the WRF model. Further, the impact of these beetle-killed forests on biogenic volatile organic compound emissions and regional air quality is currently being investigated with a regional model framework (C. Wiedinmyer, T. Sakulyanontvittaya and R. Morris (ENVIRON), and others).

 

Future Work

Future work will continue to evaluate the impact of emissions from the biosphere (biogenic emissions and emissions from fires) on atmospheric processes. Improvements to the emissions models will be completed and the evaluation of the impacts of fires on atmospheric processes will continue. A review paper about of the isoprene secondary organic aerosol formation (co-authors AM. Carlton (U.S. EPA) and J. Kroll (MIT)) will be completed. With the use of WRF-chem, the interactions between the biosphere and the atmosphere will be more thoroughly investigated. Continued evaluation of land use and climate change on emissions and atmospheric processes on a regional scale will be completed.

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References (Specific to this write-up):

Al-Saadi, J., A. Soja, R.B. Pierce, J. Szykman, C. Wiedinmyer, L. Emmons, S. Kondragunta, X. Zhang, C. Kittaka, T. Schaack, K. Bowman. (2008) Evaluation of Near-Real-Time Biomass Burning Emissions Estimates Constrained by Satellite Active Fire Detections. Journal of Applied Remote Sensing, v2, [DOI: 10.1117/1.2948785].

Avise, J., J. Chen, B. Lamb, C. Wiedinmyer, A. Guenther, E. Salathé, C. Mass. Attribution of projected changes in U.S. ozone and PM2.5 concentrations to global changes. Submitted to Atmos. Chem. Phys. Discuss., June 2008.

Chen, J., J. Avise, B. Lamb, E. Salathé, C. Mass, A. Guenther, C. Wiedinmyer, J.-F. Lamarque, S. O’Neill, D. McKenzie, N. Larkin. The Effects of Global Changes upon Regional Ozone Pollution in the United States. Submitted to Atmos. Chem. Phys. Discuss., June 2008.

Guenther, A., T. Karl, P. Harley, C. Wiedinmyer, P. I. Palmer, C. Geron (2006) Estimates of global terrestrial isoprene emissions using MEGAN (Model of Emissions of Gases and Aerosols from Nature), Atmospheric Chemistry and Physics, 6, 3181-3210. 

Jiang, X., C. Wiedinmyer, F. Chen, Z.-L. Yang, and J. C.-F. Lo (2008), Predicted impacts of climate and land use change
on surface ozone in the Houston, Texas, area, J. Geophys. Res., 113, D20312, doi:10.1029/2008JD009820.

Sakulyanontvittaya, T., A. Guenther, D. Helmig, J. Milford, C. Wiedinmyer. Secondary Organic Aerosol from Sesquiterpene and Monoterpene Emissions in the United States. Submitted Environmental Science & Technology, March 2008, in press.

Sakulyanontvittaya, T., T. Duhl, C. Wiedinmyer, D. Helmig, S. Matsunaga, M. Potosnak, J. Milford, A. Guenther (2008) Monoterpene and Sesquiterpene Emission Estimates for the United States. Environmental Science & Technology, 42 (5), 1623–1629.

Wiedinmyer, C. and H. Friedli. Mercury Emission Estimates from Fires: An Initial Inventory for the United States, in press, Environmental Science & Technology, October 17, 2007, DOI: 10.1021/es071289o.

Wiedinmyer, C. , B. Quayle, C. Geron, A. Belote, D. McKenzie, X. Zhang, S. O'Neill, and K.K. Wynne (2006) Estimating emissions from fires in North America for Air Quality Modeling. Atmospheric Environment , 40, 3419-3432.

Community Service FY08:

• Associate Editor: Journal of Geophysical Research- Atmospheres
• Member: Leadership Board, Earth Science Womens Network
• Graduate Advisor & Thesis Committee: Mike Feldman, University of Texas at Austin
• Graduate Advisor: Barron Henderson, University of North Carolina, Chapel Hill
• Graduate Advisor: Xiaoyan Jiang, University of Texas at Austin
• Graduate Advisor & Thesis Committee: Tanarit Sakulyanontvittaya, University of Colorado, Boulder

Scientific Talks FY08:

• Energy, Air Quality, and Water Systems in Colorado (Boulder, CO, October 2007)

Publications FY08:

Al-Saadi, J., A. J. Soja, R. B. Pierce, J. Szykman, C. Wiedinmyer, L. Emmons, S. Kondragunta, X. Zhang, C. Kittaka, T. Schaack, K. Bowman, 2008: Intercomparison of near-real-time biomass burning emissions estimates constrained by satellite fire data. J. Appl. Remote Sens., 2, 021504, doi: 10.1117/1.2948785.

Sakulyanontvittaya, T., T. Duhl, C. Wiedinmyer, D. Helmig, S. Matsunaga, M. Potosnak, J. Milford, A. Guenther, 2008: Monoterpene and Sesquiterpene Emission Estimates for the United States. Environ. Sci. Technol., 42, 1623-1629.

Wiedinmyer, C., H. Friedli, 2007: Mercury emission estimates from fires: An initial inventory for the United States. Environ. Sci. Technol., 41, 8092-8098, doi: 10.1021/es071289o.

Wiedinmyer, C., J. C. Neff, 2007: Estimates of CO2 from fires in the United States: implications for carbon management. Carbon Balance and Mgmt., 2, 10, doi: 10.1186/1750-0680-2-10.