Title: Fire smoke plume heights in North America: model validation using MISR and MODIS satellite observations

Abstract: Modeling efforts are currently being made to embed sub-grid plume-rise model schemes into chemical transport models. However, quantifying and modeling fire emission heights is still a difficult task because of the scarcity of plume height observations for validation. A multi-year record of aerosol smoke plume heights derived from observations made by the NASA Terra Multi-angle Imaging SpectroRadiometer (MISR) shows that fire smoke injection heights in the North American biomes are highly variable, ranging from a few hundred to 5000 meters above the terrain, at the Terra overpass time. The analysis of plume heights with assimilated meteorological observations from the NASA Goddard Earth Observing System and measurements of the MODerate resolution Imaging Spectroradiometer (MODIS) fire radiative power (FRP) indicates the important effect of both buoyancy generated by the fires and local atmospheric structure on the ultimate rise of these fire emissions. Here, we evaluate a 1-D plume-rise model driven by fire properties and local meteorology.  Fire emission injection heights are simulated considering different fire characteristic scenarios based on MODIS and empirical data, and using the MISR smoke plume height dataset as a constraint.  We find that a good measure of the instant size of the fires is needed in order to simulate well injection heights. Recommendations for the use of plume-rise models and a non-computationally parametrization of fire emission injection heights for chemical transport models are also discussed.

Recommended articles:

Val Martin, M., J. A. Logan, R. Kahn, F.-Y. Leung, D. Nelson, and D. Diner,  Smoke injection heights from fires in North America: Analysis of five years of satellite observations , Atmos. Chem. Phys., 10, 1491-1510, 2010 (www.atmos-chem-phys.net/10/1491/2010/acp-10-1491-2010.pdf)

Freitas, S. R., Longo, K. M., Chatfield, R., Latham, D., Silva Dias, M. A. F., Andreae, M. O., Prins, E., Santos, J. C., Gielow R., and Carvalho Jr., J. A.: Including the subgrid scale plume rise of vegetation fires in low resolution atmospheric transport models, Atmos. Chem. Phys., v. 7, p. 3385-3398, 2007 (www.atmos-chem-phys.net/7/3385/2007/acp-7-3385-2007.pdf)

Statement: As a scientist, I am interested in the effects of biomass burning emissions and human activities on the atmosphere and their interactions with climate. In particular, I am interested in the study of the impacts of wildfire emissions in the atmospheric composition and climate, making use of observations -both in situ and satellite measurements - interpreted with atmospheric chemistry transport and climate models. My research is also geared toward improving our understanding on how to accurately represent biomass burning processes in Earth system models, using global integrated observing systems and data assimilation techniques. For example, at present, it is unclear how best to represent the vertical distribution of fire emissions in climate and chemical transport models because of a lack of data to test parametrizations. As part of my postdoctoral work with Dr. Jennifer Logan at Harvard University, I analyzed a multi-year record of aerosol smoke plume heights over North America, derived from observations made by the Terra MISR instrument. These data were analyzed in combination with simultaneous measurements of fire radiative power (FRP) from MODIS, and GEOS assimilated meteorological observations. This study demonstrated the significant effect of fire intensity and atmospheric structure on the ultimate rise of fire emissions, and underlined the importance of considering such physical processes in modeling smoke dispersion. In on-going work, I am exploring, in collaboration with Dr. Logan, the relationship between MISR plume heights, MODIS FRP and atmospheric stability structure using a 1-D plume-rise model. We are also developing a simple parametrization of injections heights based on insights from analysis of the MISR plume heights.  

In January 2010, I joined the Earth Sciences Division of the Barcelona Supercomputing Center, Spain. Under a European Commission Framework Project, I am currently working with the global Earth System EC-EARTH, which is a state-of-the-art coupled atmospheric-ocean general circulation model, and will incorporate a sea-ice, a land, and an atmospheric chemistry model in the near future. Within this framework, I am developing a project to study the impact of biomass burning over the Mediterranean basin. Forest fire activity has increased in southern Europe over the last decades, and is expected to increase further as a result of climate change due to drier and warmer conditions. The Mediterranean basin is a region significantly sensitive to pollution due to its particular meteorology (e.g., high solar radiation, poor ventilation) and fire risk is particularly high in this region. The goal of this study is to investigate in detail the impacts of biomass burning on regional air quality and climate, and associated climate-land surface feedbacks over this region, which are still poorly understood.

Because of my research, I am very interested in participating at the NCAR-ECSA Junior Faculty Forum. The main topics addressed in the forum are strongly related to my current and future work lines. At the same time I believe that the forum will be a great opportunity for discussing my work with other scientists in the field and developing new collaborations with other forum participants.

  • No labels