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Climate Change.pptx

  1. 16 CHAPTER
  2. • A natural process in which greenhouse gases absorb heat and release it slowly back into the atmosphere • Greenhouse gases absorb heat and release it slowly, while an actual greenhouse traps warm air inside a structure.
  3. Without greenhouse gases, Earth would be too cold to support life.
  4. •H2O vapor •Carbon dioxide CO2 •Ozone O3 •Nitrous Oxide N2O •Methane CH4 •Fluorinated gases HFC’s
  5. • Latitude is a measure of a place’s distance from the equator. • The greater the latitude, the cooler a location’s overall climate will be. • Sun’s radiation strikes regions at Earth at different angles (causing different temps) and 3 regions (tropical, temperate and polar)
  6. • Earth's tilted axis causes the seasons. Throughout the year, different parts of Earth receive the Sun's most direct rays. North Pole tilts toward the Sun = summer in the N. Hemisphere. South Pole tilts toward the Sun = winter in the N. Hemisphere
  7. • Caused by convection currents resulting from rising warm air and falling cool air • Transports moisture and heat • Global wind patterns move warm air away from equator, toward poles. • Cold air moves from poles toward equator. • Winds pick up moisture and can carry it for long distances until it falls as precipitation.
  8. • Ocean currents, which are caused by a combination of unequal heating of water and unequal salinity, affect climate by transporting heat. • The ocean absorbs a lot of carbon dioxide, causing a global cooling effect. The ocean can hold 50 times more CO2 than is found in the atmosphere.
  9. The Oceans and Climate • Warmer, less saltier water moves along the surface of the ocean and colder, saltier water moves deep beneath the ocean’s surface. • Cooler saltier water sinks at the poles and warmer less saltier water from the equator moves to take the place of the cooler water.
  10. The Oceans and Climate • Normally prevailing winds blow from east to west along the equator (the winds move warm water westward) • El Niño equatorial winds weaken, surface water becomes warmer. It causes rainstorms/floods in areas that are usually dry.
  11. The Oceans and Climate • Temperatures in the Pacific ocean are colder than average. • Causing colder and wetter weather in the Midwest
  12. Other Factors That Affect Climate
  13. Other Factors That Affect Climate
  14. Other Factors That Affect Climate
  15. Lesson 16.2 Climate Change According to NASA’s Goddard Institute for Space Studies, 2009 tied for second warmest year on record, just behind 2005. The decade spanning 2000–2009 was the warmest on record.
  16. A world in which warming reaches 4°C above preindustrial levels, would be one of unprecedented heat waves, severe drought, and major floods in many regions, with serious impacts on human systems, and ecosystems
  17. 1. Rising global surface temperatures
  18. Evidence of a Warming Earth 2. Changes in precipitation patterns
  19. Evidence of a Warming Earth 3. Melting ice (glaciers, polar ice) Did You Know? Since 1986, the Larsen Ice Shelf near Antarctica has lost an area more than 3 times the size of Rhode Island. Both photos show Sperry Glacier in Montana’s Glacier National Park. Top: 1913 Bottom: 2008
  20. Evidence of a Warming Earth 4. Rising sea levels Global mean sea level has risen about 8–9 inches (21–24 centimeters) since 1880, with about a third of that coming in just the last two and a half decades. The rising water level is mostly due to a combination of melt water from glaciers and ice sheets and thermal expansion of seawater as it warms.
  21. • Direct measurement is used to study today’s climate.
  22. Studying Climate Change Cross-section of a tree trunk • Proxy indicators, such as patterns in ice cores, tree rings, give clues about past climates.
  23. Studying Climate Change • Models are used to make predictions about future climates.
  24. • According to studies, increases in greenhouse gases are the primary cause of climate change.
  25. Finding the Cause of Climate Change • The increase in greenhouse gases is mainly due to burning of fossil fuels and changes in land use.
  26. The 2015 Paris Agreement commits countries to limit the global average temperature rise to well below 2°C above pre- industrial levels, and to aim for 1.5°C. Scientists have said crossing the 1.5°C threshold risks unleashing far more severe climate change effects on people, wildlife and ecosystems. Finding the Cause of Climate Change
  27. Lesson 16.3 Effects of Climate Change In 2003, a severe heat wave in Europe killed 35,000 people.
  28. • Shifting Habitats - usually toward the poles or to higher altitudes. Californian lilacs are growing higher on mountainsides than once they did
  29. Effects on Organisms • Migrations start earlier in the spring. Did You Know? Robins arrive on a Colorado mountaintop about 2 weeks earlier than they did in 1970. Migrating sandhill cranes
  30. Effects on Organisms • Loss of ice makes hunting seals difficult for polar bears.
  31. 1. An increase in ocean temperature is associated with a process called coral bleaching, in which algae living within corals die. Without the algae, coral cannot survive.
  32. Effects of a Changing Ocean 2. Changes in ocean acidity, resulting from an increase in dissolved carbon dioxide, can harm organisms causing organisms' shells and skeletons made from calcium carbonate to dissolve. Examples of sea life that are being directly affected are oysters, clams, sea urchins, corals, and certain species of plankton.
  33. 1. Agriculture and Forestry: Effects are complex. • Can be positive: Lengthened growing season for some crops • Can be negative: Droughts and forest fires
  34. 2. Economy: Decreased yields; increased property damage due to severe storms and climate conditions Current Effects of Global Climate Change
  35. 3. Human health: Extreme heat waves increasingly common, can cause heat stroke and death Current Effects of Global Climate Change
  36. 1. Diseases: Warmer temperatures can promote spread of diseases transmitted from animals to people. Black-legged ticks, known to spread Lyme disease
  37. Future Effects of Climate Change 2. Sea level: Low-lying populated coastal areas may flood as sea levels rise. Did You Know? In the United States, 53% of the population lives in coastal areas.
  38. Future Effects of Climate Change 3. Saltwater Intrusion - contamination of aquifers resulting from rising sea levels and a decrease in glacial ice may threaten freshwater supplies.
  39. Future Effects of Climate Change 4. Freshwater depletion - a decrease in glacial ice may threaten freshwater supplies.