Locations of Coral Reef Bleaching

BLEACHING OF CORAL REEFS BY OCEAN TEMPS > 85deg F (29 deg C)

Spring bud-burst dates for Aspen in Edmonton, Beaubien and Freeland I.J.Biomet 44:53-59, 2000

The increase in growing season length over the last 50 years averaged for eight stations in Alaska having the longest and most consistent temperature records.

Area of thaw and refreeze Area of thaw only Border of dieback area Birch Decline and thaw-refreeze zone

What’s Going On?

Climate Change and Other Environmental Stress impacts on North American Forests and Rangelands Steven McNulty, USDA FS Roger Cox, NRC Allen R. Riebau, USDA FS Douglas G. Fox, CSU Gonzalez Vicente, CONAFOR Presented to the North American Forestry Commission October, 2006

400,000 Years of Antarctic CO 2 and Temperature Change Source: Climate Change Impacts on the US, NAST, 2001

Northern Hemisphere Carbon Emissions Source: Climate Change Impacts on the US, NAST, 2000

Atmospheric CO 2 Concentrations Source: Climate Change Impacts on the US, NAST, 2000

Northern Hemisphere Surface Temperature Source: Climate Change Impacts on the US, NAST, 2000

What Will Happen Next? Presented in Order from Most to Least Likely

Certain change Atmospheric CO 2 will continue to increase

Extremely Likely Water and air temperature will continue to increase

“Simulations of the response to natural forcings alone … do not explain the warming in the second half of the century”SPM Stott et al, Science 2000

“..model estimates that take into account both greenhouse gases and sulphate aerosols are consistent with observations over this period” SPM Stott et al, Science 2000

Management Strategy for Coping with Increased Sea Level Rise Coastal forests will be inundated and coastal beach erosion will increase. Forest managers should work with land owners at a local scale to plant mangroves and other soil retention vegetation to delay terrestrial loss for a long as reasonably possible.

Likely Impacts

Changing Patterns in Wildfire Occurrence

Large scale (> 400 ac) Wildfires and Air Temperature From Westerling et al. 2005

Management Strategy for Coping with Increased Wild Fire Manage for and encourage more fire tolerant grass and tree species Increase public education and preparedness regarding wild fire prevention and individual preparation and control Compared to climatic drivers, fuel reduction control measures will be largely ineffectual

Likely Impacts Inter-annual precipitation variability and soil erosion

Percent of the continental USA with a much above normal proportion of total annual precipitation from 1-day extreme events (more than 2 inches or 50.8mm) Karl et al BW 7

Uwharrie National Forest Current Soil Erosion Map

Areas of Soil Erosion By 2030 On UNF

Management Strategy for Coping with Increased Soil Erosion Continue to encourage standard soil erosion control practices such as contour plowing, winter cropping, shelter belts, and buffer strips Relocate trails away from streams Use bridge mats and culverts at stream crossings

Likely Impacts Changes in Productivity and Economic Value

> 25% DECLINE 5%-25% DECLINE <5% CHANGE 5%-25% INCREASE Timberland Acreage Shift 1993 – 2040: No Climate Change Baseline

Timberland Acreage Shifts by 2040 Due to Hadley Climate Change 5%-25% DECLINE <5% CHANGE 5%-25% INCREASE

Management Strategy for Coping with Changing Rangeland and Forest Productivity Work with local land owners to examine alternative crops (e.g., shift from red pine to loblolly pine plantations or from corn to wheat) as climate shifts occur Examine options for changing management strategy for exists crops (e.g., wider tree planting, fewer head per acre)

Less Likely Impacts Gradual Ecosystem Shifts

American beech Iverson et. al GTR NE265

Sugar maple Iverson et. al GTR NE265

Loblolly pine Iverson et. al GTR NE265

Sweetgum Iverson et. al GTR NE265

Less Likely Impacts Increasing western North American water crisis

Management Strategy for Coping with Water Stress Largely a agricultural issue. Irrigation is the largest single user of water. Shifting to a drip irrigation system will greatly reduce water stress. Large scale, sustained reductions in grasses or trees at a level sufficient to significantly increase water availability is neither economically or technically practical

Unknown Impacts of Climate Change Integrated stress impacts

2004 Canadian Acid Deposition Science Assessment Example of Critical Load Calculated for N Across Canada

Stress interactions on ecosystems Critical Load Elevated nitrogen deposition Causing altered tree physiology Climate Change Reduces N demand, changes forest composition Fire Reduces N demand, changes forest composition

How a different critical nitrogen load could be determined within the same ecosystem N dep = 10 kg/ha/yr N leaching = 0 Mortality = 0% Critical N > 10 kg Load N dep = 10 kg/ha/yr N leaching = 1 Mortality = 10% Critical = 10 kg Load + 3 yr Drought Stress N dep = 10 kg/ha/yr S dep = 10 kg/ha/yr N leaching = 15 Mortality = 75% Critical = 8 kg Load + 3 yr Drought Stress N dep = 10 kg/ha/yr N leaching = 25 Mortality = 100% Critical < 5 kg Load + 3 yr Drought Stress + fire S dep = 10 kg/ha/yr

Management Strategy for Coping with Water Stress None. More research is needed before effective management strategies could be developed

Potential Extreme Consequences (a.k.a. Armageddon Scenarios)

Gradual or Abrupt Loss of the Thermohaline to Fresh Water Inputs

Thermohaline ocean Circulation Belt Jayne Doucette, WHOI

Carbon Dioxide Loss from tundra thaw triggering a “run-away” positive feedback between air temperature and tundra peat decomposition.

Conclusions There is much we understand about climate change and the impacts it is having and will continue to have on North American rangelands and forests. There are also management strategies that can be used to minimize some of the negative impacts of climate change However, while we have great confidence in the direction of climate change, there remains uncertainly regarding the rate and ultimate level of climate change. Much of this uncertainty is due to the uncertainty of society to address future green house gas emissions.