Forests and Climate. Changing Forests. Carbon, Climate over Time. Current Forest Change. Why Should We Care? Forest Carbon Cycle

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1 Forests and Climate Continual Change, Many Possibilities Dean Hal Salwasser Why Should We Care? Forests: Keystone ecosystem for a livable earth Water, fish, wildlife, wood, jobs, wealth, air 50% global loss to other land uses Climate: Context for livability Rapid warming, unequivocal, human impact very high confidence (IPCC 2007) Human impacts augmenting natural radiative forcing The link: Trees use CO 2 to grow, CO 2 is a greenhouse gas Growth transfers carbon from atmosphere to trees Forests offset some of fossil fuel carbon emissions Forest Carbon Cycle Changing Forests Glacial-Interglacial change < 3,000 elevation change in species range < 1,000 miles latitude change in species range Species continually moving and reassembling Continual adaptation, extirpation, evolution Ecosystems never stable Post-glacial change Smaller climate change interactions Natural disturbances: fires, floods, storms Human actions: fires, harvest, restoration, land-use conversion, air pollution, species alterations Current Forest Change Carbon, Climate over Time Atmospheric CO 2 correlates to climate ~ 200 PPMC during glacial periods < 300 PPMC during interglacial periods MGST was 10 o F 18,000 ; last glacial maximum 380 PPMC in 2005 Highest level in at least 650,000 years MGST +1 o F since 1900 Fastest increase detected/recorded Average annual fossil fuel CO 2 emissions: = 6.4 PgC in 1990s (range ) = 7.2 PgC in 2000s (range ) 1 PgC = 1,000,000,000 metric tons = 3.67 PgCO 2 1

2 CO 2 Trends Over Time Orbital Climate Factors Other Climate Factors Surface Temperature Solar activity events Volcanoes Large fires Ocean current fluctuations (PDO, ENSO) Artifacts of human activities Other? Human Factor over Time Population Growth Fire from the start, > 100,000 > 12,000 humans arrive in Americas 8,000-10,000 agriculture, forest conversion in China, India, Mesopotamia; first CO 2 anomaly? ~ 5,000 paddy rice cultivation; second CO 2 anomaly? 3,000-5,500 metallurgy, wood for fuel, agriculture in Americas; third CO 2 anomaly? 2,000-3,000 spread of civilization across Euro Asia, massive forest transformation 350 industrial era, massive transfer of carbon from fossil fuels and deforestation to atmosphere; biggest CO 2 anomaly? Billion ,000 10,000 2, now

3 Its Not All Fossil Fuels! Lifestyle Impacts Population Size Factor How Much Carbon? Total biosphere pool ~ 2,190 PgC Forest pool ~ 1,000 PgC; > 50% of terrestrial pool ~ 50% more carbon than in atmospheric pool ~ 25% of carbon remaining in accessible fossil fuel pool 4,000-5,000 PgC in fossil fuel pool 38,000 PgC in deep oceans 65,000,000 PgC in carbonaceous rocks How Much Carbon? Future Scenarios Land-use change ~ 156 PgC carbon transferred to atmosphere 90% from deforestation Emissions from fossil fuel burning and cement making ~ 275 PgC Current annual land-use change ~ 1.6 PgC high uncertainty though, range Current annual fossil fuel emissions ~ 7.2 PgC 3

4 Future Scenarios Best estimate MGST increase 3-7 o F by 2100 depending on future scenario (range ) Slight change at Equator; largest change in boreal and polar regions; major impacts in PNW Very likely (90-99%) Higher max temps, higher min temps, fewer cold days, higher mean global surface temperature (MGST) Likely (< 90%) Increased summer continental drying, drought risk at mid latitudes, more large intense fires, more intense precipitation events over all land areas Warming Impacts Milder winters, hotter summers More ppt as rain than snow, increased drought stress, less summer rain Declines in water supply Earlier peak flows, lower summer flows, hydro-fish conflicts Altered growing seasons Longer growing seasons but less soil moisture, shift in growing zones More wildland fires, bigger, more intense Bad air Heat waves, pollutants from coal-fired plants, automotive emissions, particulates from wildland fires Warming Impacts Salmon declines Migration timing impacts, summer water temp higher, algal blooms, ocean conditions Wetland declines Flooded out, dried up, or relocated Biodiversity declines Native species unable to adjust to habitat changes, invasives, ecosystem composition change Pest infestations Warmer winters = fewer pest die offs; longer reproduction period = explosive natives Changing Course is Possible After Pacala and Socolow (2004) BAU All Wedges Working The Wedges Strategy 1. End-user energy efficiency and conservation 2. Power generation efficiencies, less carbon intensive 3. Carbon capture and storage at energy plant 4. Alternative energy sources, renewables 5. Agriculture and forestry Pacala and Socolow (2004), Socolow and Pacala (2006) Forest Wedge Components 1. Halt, reverse deforestation, land-use trends 2. Increase forested area (uncertainty about albedo) 3. Manage forests to store more carbon over long term, reduce vulnerability to drought, insects, fires 4. Capture more carbon in durable wood products 5. Use wood products instead of energy demanding substitutes, e.g., steel, concrete 6. Use mill waste, woody biomass for bio-based, renewable, domestic energy 7. Reward forestland owners for ecosystem services beyond producing wood 4

5 Global Forest Strategy Rotation Impacts Wedges 1 and 2 Wedge 3 Fires and Carbon Forests Plus Products Plus Displaced Energy Area and intensity of wildland fire are increasing with warming climate Potential to reduce fire impacts through forest management Transfer carbon from thinned trees to durable products or biobased energy Some CO 2 released immediately during fire Some CO 2 released slowly following fire; ultimate fate depends on actions, products CO 2 uptake as new forest grows; how fast varies with succession and management Wedges 3 and 4 Wedges 3-6 Diversifying Markets Wedge 7 What Must We Do? Create the forest wedge in a comprehensive climate strategy its more than bio-based based energy Halt, reverse deforestation, land-use conversion trends Actively use forests and forest products to sequester and store more carbon than current Restore resilience to federal forests, reduce emissions from fires, store and sequester more carbon Increase reliance on bio-based, renewable, domestic energy sources Bring carbon into forest planning, practices Create markets for ecosystem services, new incentives Create a toolbox of options, no universal correct solution 5

6 Can Any of This Happen in PNW? Yes, it is, it can, and it will. How fast and how big a wedge can we build for forests and forest products in emerging climate strategies? 6