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Global Atmospheric Changes. The Atmosphere and Climate. Solar Radiation and Climate Insolation = sunshine Major determinant of climate Makes life on Earth possible Liquid water Warm planet Photosynthesis Powers Earth’s biogeochemical cycles Drives winds and ocean currents.
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The Atmosphere and Climate • Solar Radiation and Climate • Insolation = sunshine • Major determinant of climate • Makes life on Earth possible • Liquid water • Warm planet • Photosynthesis • Powers Earth’s biogeochemical cycles • Drives winds and ocean currents
Global Climate Change • Earth’s average temperature is increasing • Based on daily measurements taken by: • Meteorological stations, weather balloons, sea-surface buoys • NOAA: global temperatures in1995 and 2001–2009 may have been highest in the last 1000 yrs • Spring in Northern Hemisphere comes 6 days earlier than in 1959, Autumn comes 5 days later • Increase in heat waves, heat-related deaths • Sea levels rising, glaciers retreating, more severe hurricanes
Global Climate Change • Scientific Consensus: • Human activities are largely responsible for current climate change • IPCC: United Nations Intergovernmental Panel on Climate Change Predicts • 1.8 to 4.0 °C (3.2-7.2 °F) increase in global temperature by 2100 • Higher maximum temperatures • More hot days, fewer cold days • Increase in heat index • Changes in precipitation patterns
Global Climate Change • Causes: • Increase of atmospheric gases due to human activities -- Greenhouse gases: • Carbon Dioxide (CO2) • Nitrous Oxide (N20) • Methane (CH4) • Chlorofluorocarbons (CFCs) • Ozone (O3) • Water (H2O) - steady amount-does not increase due to human activity
More CO2 more heat in atmosphere– more transferred back to surface
Global Climate Change • Aerosols tend to cool the atmosphere • Reflect sunlight into space • Cooling effect much weaker than enhanced greenhouse effect • Human and natural causes of aerosols • Sulfur emissions from fossil fuels • Volcanic eruptions
Global Climate Change • Effects of Climate Change: • Sea-level rise • Polar ice caps and continental glacier melts • Warm water expands in volume • Changes in precipitation patterns • More droughts in some areas • More flooding in some areas • Fresh water availability
Global Climate Change • Effects of Climate Change: • Impacts on agriculture • Rising sea levels will flood deltas • Pests will become more prevalent • No irrigation water • Productivity may increase in some areas
Global Climate Change • Effects of Climate Change: • Impacts on human health • Heat-related illnesses • Disease-carrying mosquitoes will expand their range and transmit more malaria, Dengue fever, yellow fever
Global Climate Change • Effects of Climate Change: • Impact on biodiversity and ecosystems • Warmer oceans lead to decline in populations of krillsilverfishAdelie penguins • Warmer temperatures makes frogs more susceptible to fungal diseases • Polar seas, coral reefs, coastal wetlands, tundra • Ocean acidification • Coral bleaching
Global Climate Change • Mitigation • Develop alternatives to fossil fuels • Reduce energy use • Increase energy efficiency • Plant and maintain forests • Carbon Management • Trap CO2 from smokestacks • Sequester CO2 into geological formations or depleted oil/gas wells
Global Climate Change • Adaptation • Move coastal settlements inland • Construct sea walls on coastal areas • Prevent saltwater intrusion • Find substitute crops to grow on warming land • Develop heat and drought resistant crops/trees • City planning • Sewer systems • Storm runoff