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Climate Change: A Global Phenomenon with Local Implications. Ryan Lucas Sierra Nevada Research Institute UC Merced rlucas@ucmerced.edu. Greenhouse Effect Global and Regional Temperature Trends and Forecasts Impacts to the Sierra Nevada and Central Valley Summary. Outline.
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Climate Change: A Global Phenomenon with Local Implications Ryan Lucas Sierra Nevada Research Institute UC Merced rlucas@ucmerced.edu
Greenhouse Effect Global and Regional Temperature Trends and Forecasts Impacts to the Sierra Nevada and Central Valley Summary Outline
Increased concentration of greenhouse gasses in the earth’s atmosphere CO2 – burning of fossil fuels N2O – manure breakdown, burning of fossil fuels, industrial processes, fertilizer breakdown CH4 – landfills, manure breakdown, permafrost melt H2O – “natural”, increase from melting of ice, glaciers, and permafrost Greenhouse Effect
Global Anthropogenic Greenhouse Gas Emissions – 2004 Source: IPCC 4th Assessment Report:Climate Change 2007: Synthesis Report
Greenhouse Effect A fraction of the long wave radiation escapes from the atmosphere; greenhouse gases absorb the remaining long wave radiation and emit long wave radiation in all directions. Incoming Solar Radiation Increase of greenhouse gases results in more long wave radiation absorbed and re-emitted and warmer global surface temperatures. Incoming Solar Radiation is absorbed by Earth’s surface. Surface emits long wave radiation to atmosphere
Source: http://globalchange.gov/publications/reports/scientific-assessments/us-impacts/full-report/national-climate-change
Early onset of spring Early stream flow Loss of reservoir and groundwater storage Loss of hydroelectric generated power Large winter storms produce rain Loss of storage in snow pack Induction of floods, rain on snow events Longer, drier summers Crop and stock stresses Water Impacts
Wildfires Source: Westerling 2006
More frequent wildfires More intense/larger wildfires Decrease in Central Valley air quality Loss of vegetation Loss of wildlife habitat Release of CO2 to atmosphere Fire Impacts
Vegetation Source: Linehan et al 2006
Vegetation Source: Linehan et al 2006
Potential migration of plant species Potential loss of plant species. Migration and/or loss of plant species may lead to migration and/or loss of animal species. Vegetation Impacts
Potential for 1-3 feet sea level rise by the end of the century (Hanak and Lund 2008) Alter salinity, depth, and flood potential in the Sacramento-San Joaquin Delta Sea Level
Mean global surface temperatures have been and will continue to be on the rise Warming of global surface temperatures is a result of increases in atmospheric greenhouse gas concentrations Anthropogenic activities are the major source for increases in atmospheric greenhouse gas concentration Although a global phenomenon, we will experience local impacts The western US has seen increased temperatures over the last century and will see continued temperature increases for the foreseeable future Impacts expected in the Sierra Nevada and Central Valley include: Loss in snow pack Early onset of spring runoff Longer, drier summers Increased frequency and severity of wildfires Decrease in air quality The climate will change; how much and how quickly depends on mitigation and adaptation strategies developed and implicated now and in the near future Summary