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Global Climate Change

Wicked Problems. Global Climate Change. Central Case: Rising seas may flood the Maldives. Central Case: Rising seas may flood the Maldives. Central Case: Rising seas may flood the Maldives. Our dynamic climate. Climate : an area’s long-term atmospheric conditions

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Global Climate Change

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  1. Wicked Problems Global Climate Change

  2. Central Case: Rising seas may flood the Maldives

  3. Central Case: Rising seas may flood the Maldives

  4. Central Case: Rising seas may flood the Maldives

  5. Our dynamic climate • Climate: an area’s long-term atmospheric conditions • Temperature, moisture content, wind, precipitation, etc. • Influences everything around us • Weather: conditions at localized sites over hours or days • Global climate change: describes trends and variations in Earth’s climate • Temperature, precipitation, storm frequency • Global warming: an increase in Earth’s average temperature • Earth’s climate has varied naturally through time. • The rapid climatic changes taking place now are due to human activity: fossil fuels, combustion, and deforestation.

  6. What changes climate? • Changes in: • Sun’s output • Earth’s orbit • Drifting continents • Volcanic eruptions • Greenhouse gases

  7. Global Warming

  8. The E-M Spectrum The Sun’s Energy Warms the Earth

  9. Fate of Solar Radiation Reaching the Earth reflection Clouds (20%) snow and ice + the earth’s surface (20%) atmospheric dust (6%)

  10. Fate of Solar Radiation Reaching the Earth absorption Oceans + Land (51%) Atmosphere (16%) Clouds (3%) Plant photosynthesis (<1%)

  11. Fate of Solar Radiation Reaching the Earth Radiation Radiated to space from clouds and atmosphere (64%) Radiated directly to space from Earth (6%)

  12. Earth’s Atmosphere

  13. The Greenhouse Effect

  14. Greenhouse Gases Carbon Dioxide Methane Nitrous Oxide Water Vapor Ozone

  15. Atmospheric CO2 (ppm) Temperature Change (oF) Thousands of Years Before Present

  16. Atmospheric CO2 & Surface Temperature Trends Atmospheric CO2 (ppm) Temperature Temperature Change (oF) Carbon Dioxide Year

  17. July 28, 2013:     396.77 ppm

  18. Predicted changes with increased greenhouse warming • Sea level rise • Increased plant primary productivity • Shifts in the distribution of plants and animals • Water contamination and outbreaks of water-borne diseases • Increased storm severity • Potential melting or enlargement of polar ice caps • Changes to patterns of rainfall • More severe droughts or increased precipitation • changes to ocean circulation patterns

  19. Ice Age 18,000 years ago

  20. Sea Level Changes due to Ice Ages and Ice Cap Melting

  21. Mean Sea Level Rise Changes in Mean Sea Level Year

  22. Summer Arctic Sea Ice Decline Comparison between 1979 & 2005

  23. Early Fall Arctic Sea Ice Extent Sea Ice Extent (million km2) Year

  24. Greenland Seasonal Surface Melting Surface melting

  25. Permafrost

  26. Permafrost

  27. Permafrost melting

  28. Permafrost melting

  29. Permafrost melting Drunken forest

  30. North Atlantic Tropical Storms 10-year running average Named Tropical Storms Year

  31. Larsen B Ice Shelf • 220 m thick • Lost 5700 km2 (2x Rhode Island) • Reduction of 40%

  32. 1 Meter Sea Level Rise Waikiki http://www.soest.hawaii.edu/HMRG/FloodingOahu/index.php http://www.soest.hawaii.edu/coasts/sealevel/waikiki.html

  33. Sea Level Rise • Destroys coastal habitat (e.g. salt marshes, mangroves) • Destroys human property • Increases pollution • Decreases freshwater supply Venice, 2008

  34. Effect on Marine Life • Phytoplankton bloom due to light and temperature cues • Changes will impact food web • Hypoxia may result

  35. Effect on Fisheries • Migrations are in response to temperature • May impact fisheries

  36. Effect on Corals • Coral bleaching • Leads to loss of habitat and food for reef- dependent species

  37. Currents • Oceanic conveyor belt may change ocean currents • Currents carry plankton • Bring food and oxygen • Distribute eggs and larvae • Remove wastes and pollutants

  38. Salinity • Animals have a narrow range of tolerance • Glacial melting inputs lots of freshwater

  39. Projected changes in precipitation • High latitudes = increased precipitation • Low and middle latitudes = decreased precipitation will worsen water shortages in developing countries

  40. Acidity • CO2 makes water acidic • Corals and other calcium carbonate species can’t make skeleton • Impact on plankton development impacts food web • Coral calcification rate reduced 15-20% • Skeletal density decreased, branches thinner

  41. Temperature • Higher temperature results in less O2 • - Results in hypoxia • Ice melting leaves no resting/hunting areas for polar bears • Antarctic Krill impacts food web

  42. Invasive Species • Algae smothers coral • Invasive species out-compete natives

  43. Weather Events • More severe weather patterns • El Niño • Hurricanes • Mudslides • Forest Fires • Drought

  44. Sea Surface Temperature Dec 3, 2013 http://www.elnino.noaa.gov/

  45. Origin and paths of tropical cyclones • Tropical cyclones are intense low pressure storms created by: • Warm water • Moist air • Coriolis effect

  46. El Niño-Southern Oscillation (ENSO) • El Niño = warm surface current in equatorial eastern Pacific that occurs periodically around Christmastime • Southern Oscillation = change in atmospheric pressure over Pacific Ocean accompanying El Niño • ENSO describes a combined oceanic-atmospheric disturbance

  47. El Niño • Oceanic and atmospheric phenomenon in the Pacific Ocean • Occurs during December • 2 to 7 year cycle • Sea Surface Temperature • Atmospheric Winds • Upwelling

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