The document discusses the causes and effects of global climate change. It explains that global warming is primarily driven by increased greenhouse gases from human activities like burning fossil fuels. This traps more heat in the atmosphere and causes temperatures to rise globally. Potential consequences include some areas becoming wetter or drier, rising sea levels submerging coastlines, and tropical diseases spreading farther.

1. Atmosphere Higher Geography Physical Environments

2. Don’t Panic!

7. 10 100 90 80 120 70 60 50 40 30 20 130 140 110 Height in km -100 -80 -60 -40 -20 0 20 40 Temperature ºC Temperature Change with Altitude Maximum Ozone Temperature Stratosphere Mesosphere Thermosphere Troposphere

9. Factors which influence climate on a global scale Higher Geography Atmosphere

13. The global heat budget Atmosphere 23% absorbed by atmosphere 46% absorbed by the surface 17% reflected by clouds 8% reflected by atmospheric gases and dust 6% reflected by surface 100% Solar Energy (short wave)

17. Energy Receipt with Latitude Factors which influence climate on a global scale

19. Tropical latitudes receive more solar radiation than the polar latitudes for 3 main reasons. In Polar regions the radiation has to penetrate a greater depth of atmosphere (absorbs more heat). The same amount of solar energy is received over a much greater area in Polar regions (less heating). High energy loss at poles because of ice cap albedo. Equator (0 º) North Pole South Pole

21. Albedo of various surfaces 5 - 10 Forest 15 - 25 Dry Soil 25 - 30 Grass 20 - 30 Sand (Beach or Desert) 50 - 60 Old Snow 80 - 85 Fresh Snow % Reflected Surface

23. What does this mean? 90 ºN 60 ºN 30 ºN Equator 0 º 30 ºS 60 ºS 90 ºS 0 100 200 300 Insolation (Joules) Latitude 35 ºN 35 ºS Terrestrial Radiation Insolation There is a net gain (surplus) of energy in Tropical areas because incoming radiation exceeds outgoing radiation. However in polar areas there is a net loss (deficit) of energy because outgoing radiation is greater that incoming radiation.

25. 90 ºN 60 ºN 30 ºN Equator 0 º 30 ºS 60 ºS 90 ºS 0 100 200 300 Insolation (Joules) Latitude 35 ºN 35 ºS Energy Surplus Energy Deficit Energy Deficit However, energy is transferred from areas of surplus (Tropics) to areas of deficit (Poles) by atmospheric circulation and by ocean currents.

27. Understanding Pressure Higher Geography Atmosphere

30. Atmospheric Pressure Outer edge of the atmosphere The Earth’s atmosphere presses down on the surface of the Earth. Atmospheric pressure is measured in millibars ( mb ). The average atmospheric pressure is 1000mb.

33. Low Atmospheric Pressure Outer edge of the atmosphere The Earth’s surface is warmed by the sun’s rays. The Earth’s atmosphere presses down on the surface of the Earth. Warm air rises . This reduces the weight of air pressing down on the Earth’s surface. Low Pressure

35. High Atmospheric Pressure Outer edge of the atmosphere The Earth’s atmosphere presses down on the surface of the Earth. Cold, dense air falls. This increases the weight of the air pressing down on the Earth’s surface. High Pressure

36. High and Low pressure together Outer edge of the atmosphere The Earth’s surface is warmed by the sun’s rays. Warm air rising causes LOW pressure. Cold air falling causes HIGH pressure. WIND

37. High and Low pressure together Outer edge of the atmosphere The Earth’s surface is warmed by the sun’s rays. Warm air rising causes LOW pressure. Cold air falling causes HIGH pressure. WIND WIND

41. Ocean Currents Higher Geography Atmosphere

47. Gulf stream North Pacific Drift North Atlantic Drift North Equatorial East Greenland West Australian West Wind Drift Brazil Current

50. The Thermohaline Conveyor Surface currents (such as the Gulf Stream) head polewards from the equatorial Atlantic Ocean, This dense water then flows downhill into the deep water basins Resurfacing in the northeast Pacific Ocean 1200 years later Deep Cold Water Warm Water Deep Cold Water Shallow Warm Water Shallow

54. Global Climate Change The Physical Core Atmosphere

56. Global Climatic Change Time (thousands of years) Average global temperature ( °C) 150 100 125 10 25 50 75 Present 10 15 20 Last Interglaciation Present Interglaciation Last Glaciation

57. Average Global Temperature 0.4 0.2 0 -0.2 -0.4 0.6 -0.6 1860 1880 1900 1920 1940 1960 1980 2000 Temperature Anomaly ( ºC) Year

60. Greenhouse effect Carbon Dioxide is a greenhouse gas, which means that it allows through energy from the Sun but absorbs heat from the Earth 1. The sun warms the Earth. 2. The Earth reflects some heat away… 3. …but this can’t escape into space. It is trapped by greenhouse gases. THIS MEANS As carbon Dioxide builds up in the atmosphere (30% more than 200 years ago), the Earths air temperature rises. Earths atmosphere