CharSiM is an effort to gain insights into the origin of sediment-charcoal records by explicitly modeling the processes affecting charcoal production, dispersal, and deposition, and sediment mixing and subsampling. This project involves Phil Higuera and applied mathematician Matthew Peters.

The individual components of CharSiM.

(Proportion of area burned in AK by fires of different sizes)

Simulating charcoal dispersal from a single injection height:

Description and illustration of a theoretical dispersal model (Sutton, 1947; Chamberlain, 1953) parameterized based on charcoal collected from the International Crown Fire Modeling Experiment. (ICFME) The theoretical model is coarsely evaluated by using it to predict the observed values from the ICFME.

Creating charcoal dispersal "tables" for CharSiM:

Using the theoretical dispersal model we can derive grids of charcoal source area that are used to calculate charcoal deposition in CharSiM. A grid for a single modal injection height is then integrated across a theoretical distribution of injection heights and an empirical distribution of wind directions. This simulated the variability in injection heights and wind directions that occurr during any single fire.

Bettles, AK wind patterns, 1971-2000: data used to parameterize mean wind directions

Example records from fire regime with 100 yr mean fire return interval, including secondary depositional processes, mixing, and sampling.

This component of CharSiM uses analytical techniques similar to those used on fossil charcoal records to interpret fire timing and fire-frequency regimes. Because the fire history that created the record is known, the accuracy of any single interpretation can be quantified, and different techniques can be compared and evaluated.

Flagstaff Talk