Greenhouse Effect

GreenhouseEffectFRANCISCO VITORINO Nº3027

MANUEL ALCÂNTARA Nº2999

Index

What is Who discovered Greenhouse gases Consequenses Video Conclusion Bibliography

What is Greehouse Effect

Is a process by which thermal radiation from a planetary surface is absorbed by atmospheric greenhouse gases, and is re-radiated in all directions. Since part of this re-radiation is back towards the surface, energy is transferred to the surface and the lower atmosphere

The temperature there is higher than it would be if direct heating by solar radiation were the only warming mechanism

Who discovered

Jean Baptiste Joseph Fourier (21 March 1768 – 16 May 1830) was a French mathematician and physicist born in Auxerre and best known for initiating the investigation of Fourier series and their applications to problems of heat transfer and vibrations. The Fourier transform and Fourier's Law are also named in his honor.

Who discovered

In the 1820s Fourier calculated that an object the size of the Earth, and at its distance from the Sun, should be considerably colder than the planet actually is if warmed by only the effects of incoming solar radiation.

He examined various possible sources of the additional observed heat in articles published in 1824 and 1827. Fourier's consideration of the possibility that the Earth's atmosphere might act as an insulator of some kind is widely recognized as the first proposal of what is now known as the greenhouse effect.

Greenhouse Gases

Carbon dioxide (CO2) - Fossil fuel use is the primary source of CO2. The way in which people use land is also an important source of CO2, especially when it involves deforestation. Land can also remove CO2 from the atmosphere through reforestation, improvement of soils, and other activities.

Methane (CH4) - Agricultural activities, waste management, and energy use all contribute to CH4emissions.

Nitrous oxide (N2O) - Agricultural activities, such as fertilizer use, are the primary source of N2O emissions.

Fluorinated gases (F-gases) - Industrial processes, refrigeration, and the use of a variety of consumer products contribute to emissions of F-gases, which include hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF6).

Consequences

More drought and more flooding Less ice and snow More extreme weather incidents Rising sea level

More drought and more flooding

WHEN THE WEATHER GETS WARMER, EVAPORATION FROM BOTH LAND AND SEA INCREASES. THIS CAN CAUSE DROUGHT IN AREAS OF THE WORLD WHERE THE INCREASED EVAPORATION IS NOT COMPENSATED FOR BY MORE PRECIPITATION.

IN SOME REGIONS OF THE WORLD THIS WILL RESULT IN CROP FAILURE AND FAMINE ESPECIALLY IN AREAS WHERE TEMPERATURES ARE ALREADY HIGH. THE EXTRA WATER VAPOUR IN THE ATMOSPHERE WILL FALL AGAIN AS EXTRA RAIN, WHICH CAN CAUSE FLOODING IN OTHER PLACES IN THE WORLD.

Less ice and snowWORLDWIDE, GLACIERS ARE SHRINKING RAPIDLY AT PRESENT. ICE APPEARS TO BE MELTING FASTER THAN PREVIOUSLY ESTIMATED. IN AREAS THAT ARE DEPENDENT ON MELTWATER FROM MOUNTAIN AREAS, THIS CAN CAUSE DROUGHT AND LACK OF DOMESTIC WATER SUPPLY.

ACCORDING TO THE IPCC, UP TO A SIXTH OF THE WORLD'S POPULATION LIVES IN AREAS THAT WILL BE AFFECTED BY MELTWATER REDUCTION.

more extreme weather incidents

THE WARMER CLIMATE WILL PROBABLY CAUSE MORE HEATWAVES, MORE VIOLENT RAINFALL AND ALSO AN INCREASE IN THE NUMBER AND/OR SEVERITY OF STORMS.

Rising sea levelSEA LEVEL RISES BECAUSE OF MELTING ICE AND SNOW AND BECAUSE OF THE THERMAL EXPANSION OF THE SEA (WATER EXPANDS WHEN WARMED). AREAS THAT ARE JUST ABOVE SEA LEVEL NOW, MAY BECOME SUBMERGED.

SOME PACIFIC ISLAND NATIONS ARE EXPECTED TO BE COMPLETELY SUBMERGED BY THE END OF THE CENTURY.

IN COUNTRIES WITH LARGE AREAS OF COASTAL LOWLAND THERE WILL BE A DUAL RISK OF RIVER FLOODS AND COASTAL FLOODING, WHICH WILL REDUCE THE AREA FOR LIVING AND WORKING. COASTAL DEFENCES WILL NEED TO BE STRENGTHENED, AND RIVER LEVEES WILL NEED TO BE DEVELOPED.

Bibliography

http://www.bgs.ac.uk/discoveringGeology/climateChange/CCS/consequencesOfTemperatureIncrease.html

https://www.google.pt/imghp

http://www.epa.gov/climatechange/ghgemissions/global.html

http://environment.nationalgeographic.com/environment/global-warming/gw-overview-interactive/

http://en.wikipedia.org/wiki/Greenhouse_effect

http://en.wikipedia.org/wiki/Joseph_Fourier