1. Effects of Climatic Variability and Change on Forest Resources: A Scale- based Framework for Analysis David L. Peterson USDA Forest Service, PNW Station UW College of Forest Resources UW Climate Impacts Group

2. Temperature varies over time

3. Forest vegetation varies over time

4. PDO affects tree growth Subalpine fir in the Cascade and Olympic Mountains From Peterson et al. (2002) 1920 1930 1940 1950 1960 1970 1980 1990

5. Low elevation forest Summer precipitation Summer temperature PDSI PDO Summer soil moisture

6. PDO affects growth of semi-arid tree species Ponderosa pine in the Cascade Range Data from G. Ettl 1900 1920 1940 1960 1980 2000

7. Subalpine conifer regeneration warm, cool, dry wet

8. Limiting factors in forest ecosystems High-elevation forests Duration of growing season at treeline Summer soil moisture at lower and drier locations Low-elevation forests Summer soil moisture Semi-arid forests Summer soil moisture

9. How does climatic variability affect wildfire?

10. Years with fire area > 80,000 hectares National Forest data, 1916-2002 Warm-phase PDO Cool-phase PDO Idaho 14 7 Oregon 14 5 Washington 10 2 TOTAL 38 (73%) 14 (27%)

11. Climatology affects wildfire in the Pacific Northwest Extreme wildfire years are forced at least in part by antecedent drought and summer blocking in the 500 hPa height field. From Gedalof et al. (2004)

12. Climatic change effects From McKenzie et al. (2004) Temperature ( o C) Precipitation (%) Fire area Oregon 1916-2002

13. Stress Interactions, Disturbance Increased fire risk Higher fire frequency Higher fire intensity, esp. eastside where fuel hazard is high Increased insect outbreaks, esp. eastside Postfire stress Low vigor stands with high stem density

14. Forest Carbon Budgets Storage (quantity) vs. uptake (rate) Young forest Storage Uptake Mg/ha Mg/ha/yr 50-100 5-10 Old forest 400-1000+ + 1.0? (600?)

15. Local (small watershed) Subregional (large watershed, national forest) Regional PaleoecologyLowModerateLow Growth and productivity HighModerateModerate, depends on ecosystem CarbonModerateLow RegenerationModerateLow GeneticsLow Disturbance ecology HighModerateModerate, mostly for fire Scale-based framework: knowledge base

16. Management authority Federal Forest Service Bureau of Land Management State WA Department of Natural Resources OR Department of Forestry Private Industrial forest Nonindustrial forest

17. Response capacity Federal Carbon management (storage, LCA) Altered planting strategies Fire mitigation State Carbon management (storage) Private Industrial forest -- Genotype management -- Carbon management (storage, LCA) Nonindustrial forest -- None; default carbon storage?

18. THANK YOU! David L. Peterson peterson@fs.fed.us 206.732.7812 http://www.fs.fed.us/pnw/fera