Natural and Unnatural Greenhouse Effect SNC2D1 Mr. Findlay

Did You Know? With dry ice and a plane, you can create a rainstorm. Here’s how cloud seeding, or making rain artificially works: A plane drops crushed dry ice into a cloud; The dry ice attracts water droplets and ice crystals; These crystals get bigger and heavier until they fall to Earth as rain. Not everyone agrees on how useful and fair it is to use this process.

Natural Greenhouse Effect Earth depends on energy coming from the Sun. About half of the energy received is absorbed and re-radiated as infrared heat. 90% is then absorbed by Greenhouse Gases and radiated out in all directions. The surface maintains an average temperature of 15oC due to this effect. Without these gases, the Earth would be 33o cooler with an average temperature of -18oC.

Natural Greenhouse Effect

Why are they called greenhouse gases? Act like the glass of a greenhouse. Visible light passes by but infrared light is reflected.

What are the greenhouse gases? Most abundant Traps heat and radiates some of it back to Earth Water Vapour (H2O) Minor component of the atmosphere but very important Humans have increased the concentration by 33% since the Industrial Revolution Carbon Dioxide (CO2) Powerful greenhouse gas produced by agriculture Sources: fertilizers, fossil fuel combustion, nitric acid production, and biomass burning. Nitrous Oxides (N2O)

What are the greenhouse gases? Hydrocarbon produced through natural processes and human activities Cows are a major producer of methane through the release of gas and wastes Methane (CH4) Major concern in the troposphere Acts as a ceiling, blocking or trapping heat closer to the Earth Ozone (O3) Synthetic compounds developed for industrial purposes Contribute to the destruction of the ozone layer in the stratosphere Chlorofluorocarbons (CFC)

Unnatural Greenhouse Effect Discovery of petroleum based fuels on Earth and the knowledge to burn them has contributed to massive amounts of carbon dioxide being released into the atmosphere. Increasing greenhouse gases through human activities is called the anthropogenic greenhouse effect.

Anthropogenic Greenhouse Effect

Greenhouse Gas Production Rank Country Annual CO2 Emissions (thousands) Percentage of total emissions Country’s Population (thousands) Emissions per Capita (tonnes) 1 China 6 103 493 21.5% 1 333 440 4.58 2 United States 5 752 289 20.2% 307 666 18.70 3 Russia 1 564 669 5.5% 141 882 11.03 4 India 1 510 351 5.3% 1 170 020 1.29 5 Japan 1 293 409 4.6% 127 540 10.14 6 Germany 805 090 2.8% 82 002 9.82 7 United Kingdom 568 520 2.0% 61 634 9.22 8 Canada 544 680 1.9% 33 806 16.11 9 South Korea 475 248 1.7% 48 333 9.83 10 Italy 474 148 1.6% 60 114 7.89

Evidence of Climate Change