Greenhouse Effect and Global Warming

Greenhouse Effect How we stay warm

The Sun’s energy reaches Earth through: Radiation heat traveling through Space

What is Insolation? The incoming solar radiation (energy from the Sun) that reaches Earth

How much solar radiation reaches Earth? Earth’s surface only absorbs 51% of incoming solar radiation In the atmosphere clouds account for the greatest absorption of radiation (19%)

Greenhouse Effect The process by which gasses absorb heat energy from the sun and prevent heat from leaving our atmosphere. In other words, greenhouse gases trap heat energy and keep it close to earth.

Greenhouse Gases Primary Secondary Water vapor Carbon dioxide Methane Nitrous oxide Ozone

Natural Greenhouse Gases Volcanic eruptions- mainly carbon dioxide Methane – from decomposition Nitrous oxide- from denitrification Water vapor

Anthropogenic (Man-made) Sources Greenhouse Gases deforestation (CO2) fossil fuel combustion (CO2) cattle digestive gas emissions (methane)

Anthropogenic Sources Greenhouse Gases

Is the Greenhouse Effect Good or Bad? It is necessary for life (good) when it keeps our climate toasty warm and prevents it from fluctuating (changing) too much It is bad when there are too many greenhouse gasses and the climate gets warmer (GLOBAL WARMING)

What is Global Warming? A theory that the Earth is gradually getting hotter an hotter. It is caused by an increase in Greenhouse Gases in the Atmosphere Global warming could lead to an increase in: Hurricanes Floods Heat waves Tornadoes

Temperature change over past 22,000 years Agriculture established 1 Average temperature over past 10,000 years = 15°C (59°F) -1 End of last ice age Temperature change (°C) -2 -3 -4 -5 20,000 10,000 2,000 1,000 200 100 Now Years ago 22,000

Temperature change over past 1,000 years Temperature change (°C) 1.0 0.5 Temperature change (°C) 0.0 -0.5 -1.0 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2101 Year 1000

130 years Average temperature over past 130 years 15.0 14.8 14.6 14.4 Average surface temperature (°C) 14.2 14.0 13.8 13.6 1860 1880 1900 1920 1940 1960 1980 2000 2020 Year 130 years

Natural Climate Variation Natural factors affecting temperature volcanic eruptions variations in cloud cover ocean currents Evidence ice core data fossil record of species (plant & animal)

5 Things that cause an Increase in Greenhouse gases CARBON DIOXIDE added to the atmosphere when people burn fossil fuels

5 Things that cause an Increase in Greenhouse gases Deforestation increases the amount of carbon dioxide in the air because in photosynthesis plants take in carbon dioxide and remove it from the atmosphere, they make oxygen.

5 Things that cause an Increase in Greenhouse gases Volcanoes, fires, and respiration add CO2 to the atmosphere Carbon Cycle

5 Things that cause an Increase in Greenhouse gases Methane produced when garbage is buried in landfills, from animal waste, and from other natural sources.

5 Things that cause an Increase in Greenhouse gases As temperatures increase evaporation increases which adds water vapor