2 GREENHOUSE EFFECTEarth is unique in the solar system in that it is the only planet that supports life as we know it.Several factors account for this:Position near the sun: not too close, not too farAbundance of waterRight mixture of chemical compounds needed for lifeRight types of gasses in the right combination making up our atmosphere
3 Right types of gasses in the right combination make up our atmosphere GREENHOUSE EFFECTLet’s look at the last factor…Right types of gasses in the right combination make up our atmosphereWhy is this so important?
4 GREENHOUSE EFFECTThe earth’s atmosphere is a protective blanket which surrounds our planet.It allows the right amounts of sun’s energy in and out, creating a climate that is supportive of life
5 SUN’S ENERGYThe sun’s energy reaches the earth in the form of electromagnetic radiation.Electromagnetic radiation includes visible light, infrared (heat), ultraviolet wave lengths and others forms of energy.
6 SOLAR ENERGYTwo things can happen to solar radiation as it approaches earth’s atmosphereSolar radiation can be reflected back into spaceSolar radiation can be absorbed by clouds, gases like ozone or earth’s surface - or scattered by the atmosphere.
7 SOLAR RADIATIONSome of the solar radiation is reradiated or emitted by the earth in the form of long-wave radiationThis long-wave radiation is absorbed by certain gasses in the earth’s atmosphere.These gasses are called “greenhouse gasses”
8 GREENHOUSE GASSES Naturally Occurring Water Vapor Methane Nitrous OxideCarbon DioxideInfluenced by humansCFC’sOzone (?)
10 The level of greenhouse gases can be affected by man-made and natural processes
11 MAN-MADE PROCESSES Burning fossil fuels→CO2 and NOx Removing vegetation (deforestation)→CO2Using aerosols→CFCPolluting of oceans and waterways →methane
12 NATURAL PROCESSES Volcanic Eruptions Carbon Cycle Water Cycle Decay→methaneOceans and bacteria in soil→nitrous oxide
13 MAN-MADE CONTRIBUTIONS Man-made contributions to greenhouse gases are potentially devastatingThe rise in greenhouse gases, especially carbon dioxide, are being attributed to a general rise in earth’s temperature.
14 These two graphs show the relationship between carbon dioxide concentrations in ice core data/Mauna Loa data and global average temperatures.There seems to be a direct correlation between the two
15 So what are the consequences of an overall rising temperature on Earth?
16 CONSEQUENCESSeveral theories exist as to what may become of our earth if temperature continue to riseRise in sea level due to melting glaciersBalance of salt water in oceans will change, possibly affecting wildlifeMore tropical, dry weather in parts of worldIncrease in severe weather