1 / 11

Savanna fire impacts on regional and global climate

Savanna fire impacts on regional and global climate. William Sea. CSIRO Marine and Atmospheric & Land and Water Research Canberra.  Natural Resource Ecology Laboratory Colorado State University. 4 February 2008. Ozflux08. PhD Research Questions.

halima
Download Presentation

Savanna fire impacts on regional and global climate

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Savanna fire impacts on regional and global climate William Sea CSIRO Marine and Atmospheric & Land and Water Research Canberra  Natural Resource Ecology LaboratoryColorado State University 4 February 2008 Ozflux08

  2. PhD Research Questions Mortality:How do increases in tree mortality (juvenile and adult) change steady state woody basal area in a demographic-competition model compared with a traditional aggregated logistic model? Stochasticity:How does stochasticity in fire intensity and frequency impact woody dynamics relative to mean-field simulations? Initial Values:How do changes in initial values of basal area affect the steady state values (B*) in the demographic model compared with the logistic model? Competition Asymmetry:How do changes in the magnitude of asymmetric tree-grass competition lead to changes in steady state basal area values?

  3. Demographic-Competition Model Juveniles: (1) Adults: (2) Basal Area: (3) Grass Biomass: (4)

  4. Analytical Implicit Solutions Methods: Set each equation to zero. * Isolate critical bifurcation parameter, adult mortality (μA ), on the left side of equation relating all parameters and steady state basal area values (B*). Substitute in the full range of B* values and solve for μA. Basal area (B*) Plot μAvs B* .

  5. Effects of Stochastic Fire Mortality Biennial Burns (2 yr) Mean Adult mortality = 2% Juvenile mortality = 50 % Grass Biomass (green) Tree Basal Area (black) Normalized to 1 = max

  6. Postdoctoral Project Goal Improve the modelling of vegetation dynamic and emissions of aerosol and greenhouse gases from biomass burning of savannas in ACCESS • Stage 1: Compilation of data sets including global savanna tree cover, vegetation and soil carbon, and if possible seasonal variation. • Stage 2: Calibrate CASA-CNP using data. • Stage 3: Calculate emissions of aerosol particles, black carbon, CO2, Co, CH4 and N20 from savanna fires with frequency and extent based on remote sensing and fire load estimated from CASA-CNP. Run a global model to calculate radiative forcing based on savanna fire emissions.

  7. 2007 Fires in Australia

  8. Modis-derived global fire loss Vander Werf (2007)

More Related