Global Warming occur in the history


Global temperatures on both land and sea have increased by 0.75 °C (1.35 °F) relative to the period 1860–1900, according to the instrumental temperature record. This measured temperature increase is not significantly affected by the urban heat island effect. Since 1979, land temperatures have increased about twice as fast as ocean temperatures (0.25 °C per decade against 0.13 °C per decade). Temperatures in the lower troposphere have increased between 0.12 and 0.22 °C (0.22 and 0.4 °F) per decade since 1979, according to satellite temperature measurements. Temperature is believed to have been relatively stable over the one or two thousand years before 1850, with possibly regional fluctuations such as the Medieval Warm Period or the Little Ice Age.
Sea temperatures increase more slowly than those on land both because of the larger effective heat capacity of the oceans and because the ocean can lose heat by evaporation more readily than the land.Since the northern hemisphere has more land mass than the southern it warms faster; also there are extensive areas of seasonal snow cover subject to the snow-albedo feedback. Although more greenhouse gases are emitted in the northern than southern hemisphere this does not contribute to the asymmetry of warming as the major gases are essentially well-mixed between hemispheres.
Based on estimates by NASA's Goddard Institute for Space Studies, 2005 was the warmest year since reliable, widespread instrumental measurements became available in the late 1800s, exceeding the previous record set in 1998 by a few hundredths of a degree. Estimates prepared by the World Meteorological Organization and the Climatic Research Unit concluded that 2005 was the second warmest year, behind 1998.
Anthropogenic emissions of other pollutants—notably sulfate aerosols—can exert a cooling effect by increasing the reflection of incoming sunlight. This partially accounts for the cooling seen in the temperature record in the middle of the twentieth century, though the cooling may also be due in part to natural variability.
Paleoclimatologist William Ruddiman has argued that human influence on the global climate began around 8,000 years ago with the start of forest clearing to provide land for agriculture and 5,000 years ago with the start of Asian rice irrigation. Ruddiman's interpretation of the historical record, with respect to the methane data, has been disputed.

Posted in: on Saturday, November 10, 2007 at at 4:12 PM 0 comments

What we can do?


There are ways we can help cut greenhouse gases and help stop global warming. They are very simple things, but can make a different if everyone does them!

1. Re-cycle glass bottles, jars, newspapers and magazines and tin cans. Save them and take them to local re-cycling centres.
2.Re-use plastic shopping bags and envelopes.

3.Put a brick in a plastic bag into your toilet cistern, then the toilet will use less water each time you flush.
4.Use paper on both sides. Try and buy products that don't use much packaging.
5.Give unwanted gifts and clothes to a charity shop.
6.Only fill the kettle up with the amount of water you need to boil that time.
7.Don't leave the TV , video, or computer on standby.
8.If you get lift to school in a car, take your mates along for the ride.
9.Switch lights off when you're not in the room.
10.Get a clockwork mobile phone recharger.
11.Cycle to places!



Posted in: on at at 3:50 PM 0 comments

What could happen if the global warming are occur!


If the earth gets hotter, some of the important changes could happen:


1.Water expands when it's heated and oceans absorb more heat than land, so sea levels would rise.
2.Sea levels would also rise due to the melting of the glaciers and sea ice.
3.Cities on coasts would flood.
4.Places that usually get lots of rain and snowfall might get hotter and drier.
5.Lakes and rivers could dry up.
6.There would be more droughts making hard to grow crops.
7.Less water would be available for drinking, showers and swimming pools.
8.Some plants and animals might become extinct because of the heat. 9.Hurricanes, tornadoes and other storms which are caused by changes in heat and water evaporation may get more common.

Posted in: on at at 3:36 PM 0 comments

Global Warming was bad??????????



Global Warming can be good ,but sometime it will become bad when the extra greenhouse gases are made the blanket gets thicker and too much heat is kept in the earth's atmosphere.
The earth naturally warmed by rays from the sun ,the rays pass though the earth's atmosphere and reflected back out to the space again, keep the earth at the right temperature for plants, animals and humans to survive. The atmosphere made up of gaess, some call the "Greenhouse Gases". So some of the global warming was good, not that bad we know!!!!!

http://news.bbc.co.uk/cbbcnews/hi/find_out/guides/world/global_warming/newsid_1575000/1575457.stm



Posted in: on at at 3:22 PM 0 comments

The greenhouse cause the global warming




Almost 100% of the observed temperature increase over the last 50 years has been due to the increase in the atmosphere of greenhouse gas concentrations like water vapour, carbon dioxide (CO2), methane and ozone. Greenhouse gases are those gases that contribute to the greenhouse effect (see below). The largest contributing source of greenhouse gas is the burning of fossil fuels leading to the emission of carbon dioxide.

The greenhouse effect when sunlight reaches Earth's surface some is absorbed and warms the earth and most of the rest is radiated back to the atmosphere at a longer wavelength than the sun light. Some of these longer wavelengths are absorbed by greenhouse gases in the atmosphere before they are lost to space. The absorption of this longwave radiant energy warms the atmosphere. These greenhouse gases act like a mirror and reflect back to the Earth some of the heat energy which would otherwise be lost to space. The reflecting back of heat energy by the atmosphere is called the "greenhouse effect".

The major natural greenhouse gases are water vapor, which causes about 36-70% of the greenhouse effect on Earth (not including clouds); carbon dioxide CO2, which causes 9-26%; methane, which causes 4-9%, and ozone, which causes 3-7%. It is not possible to state that a certain gas causes a certain percentage of the greenhouse effect, because the influences of the various gases are not additive. Other greenhouse gases include, but are not limited to, nitrous oxide, sulfur hexafluoride, hydrofluorocarbons, perfluorocarbons and chlorofluorocarbons.


Greenhouse gases in the atmosphere act like a mirror and reflect back to the Earth a part of the heat radiation, which would otherwise be lost to space. The higher the concentration of green house gases like carbon dioxide in the atmosphere, the more heat energy is being reflected back to the Earth. The emission of carbon dioxide into the environment mainly from burning of fossil fuels (oil, gas, petrol, kerosene, etc.) has been increased dramatically over the past 50 years, see graph below.

Posted in: on Tuesday, November 6, 2007 at at 7:34 PM 0 comments

What is Global Warming?


Global Warming: Global warming refers to an average increase in the Earth's temperature, which in turn causes changes in climate. A warmer Earth may lead to changes in rainfall patterns, a rise in sea level, and a wide range of impacts on plants, wildlife, and humans. When scientists talk about the issue of climate change, their concern is about global warming caused by human activities.

Link: http://epa.gov/climatechange/kids/gw.html

Global Warming is the big problem that we need to pay attendtion, it will damage the earth and cause a lots of problem. Some place may dissappear, so let's start to do something!

Posted in: on Monday, November 5, 2007 at at 8:58 AM 0 comments

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