1. OGWC – Forest C
Bev Law
Prof. Global Change Biology & Terrestrial Systems Science
Oregon State University
Oct 6, 2016

2. Fire Emissions
Annual Net Ecosystem Carbon Balance = NEP – fire emissions – harvest emissions NEP = Aboveground NPP – dead wood decomposition – litterfall + Δ root +Δ soil C : FS estimate was “area at risk.” OSU estimate for based on fire severity burn area (L, M, H) and region- and pool-specific combustion factors (OSU sum=11.4 TgC)
FS est of Ha at risk = 26 x MTBS estimates (total for 10 yrs)
TgC/ha = 4.37 x avg calculated from OSU ha burned
OSU est: Actual fire emissions were calculated using burn area and severity (MTBS) and biomass-specific combustion factors for the region, including live and dead pools. The studies represent several of the dominant forest types in our region covering 67% of the forested area.
(Updated Hudiburg et al. 2011)

3. OSU estimate of fire emissions in Oregon (Annual for 2001-2014)
Sum Tg C emissions
Fire emissions averaged 1.14 Tg C yr-1, ~9% of the equivalent FFE for Oregon
(updated years Hudiburg et al. 2011)

4. Wildfire in Oregon 1984-2014 (length of record)
Wildfire Trends
2015 Wildfire Detections
Percent of Burn Area by Severity
Credit: USDA FS RSAC
MODIS Active Fire Detections
Since Jan. 1, 2015
2015 Statistics from: Fire season officially ended Oct 28, but there could be more.
87,584 acres shown as gray bar in lower plot – is the ODF protected forestland burned area – total area most likely much larger, especially considering the 631K number given. “forestland jurisdictions” are e.g. FS, ODF forested areas
“In 2015, more than 631,000 acres burned on all forestland jurisdictions in Oregon. Firefighting costs totaled $240.5 million” – statement from the blogspot website above ($183M in 2013, when burn area was comparable to 2015)
All other years ( ) from MTBS data.
Map is current as of Nov 3, 2015
No significant trend in area burned and total number of fires
No significant trend toward high severity
87K acres burned on lands protected by ODF
Human-caused ignitions ~75% of total
(Adapted from Law & Waring, 2015; Oregon data only;

5. Biomass Mortality From Wildfires in Oregon 1984-2012
Forest mortality from fire ( ) and insects ( ) across Oregon. Neither time series showed a significant (P<0.05) trend.
Biscuit Fire mortality shows up over this period as the dominant include.
No significant trend in biomass mortality
(data from Law & Waring, 2015, Berner et al. in review)

6. Oregon annual C emissions and forest C sink
Fire emissions were 17% of sum of fire and harvest emissions/yr
All unreserved forests
Harvest emissions = residue + wood lost in mfr + wood decomposition over time from product use
Fire emissions = severity area burned x pools x region-specific combustion factors (live, dead, surface litter)
(Hudiburg et al. 2011, updated)

7. Future Scenario Thin only forests where MFRI<40 yrs
35% of biomass per unit area
East-side: 14 Tg C net emissions over next 30 years
CLM+LCA
(Hudiburg et al. EST 2013)