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GLOBAL WARMINGQ:What is global warming?
A:From the words “Global warming, we can find out the meaning – it’s the globe warming up.
Global warming is the way in which average temperatures around the world are rising.Global warming is already having significant and harmful effects on our communities, our health, and our climate. Sea level rise is accelerating. The number of large wildfires is growing. Dangerous heat waves are becoming more common.
The greenhouse effectMost of the Sun’s rays can pass right through the atmosphere, allowing their energy to warm the Earth.The warmed planet radiates heat back into space, but some of this is absorbed by carbon dioxide and a few other gases in the atmosphere.This warms the air, meaning that it retains the heat. This effect keeps the average temperature on Earth roughly 30°C (86°F) higher than it is on the Moon, which has no atmosphere.If heat were not retained in this way, life could not exist.Greenhouse gases are important, we need them, without them, all the heat from the Earth would escape.Without greenhouse gases we couldn’t survive at night, when there’s no sunlight.
Our Changing ClimateThe greenhouse effect is vital to life on Earth.But we are adding more carbon dioxide and other greenhouse gases to the atmosphere – mainly by burning coal, oil, and gas, but also by cutting down and burning forests.This makes the atmosphere retain more heat, raising the average air temperature, warming the oceans, and melting polar ice. This could have serious consequences for all life on the planet
OUR changing climate - 2Climate change is how climates around the world are changing, because of the rise in average air temperatures.
As the air around the Earth warms up…
1.Rainfall patterns changeSome places are already getting more rain than before. Some are getting less.
2.Wind patterns changeWind patterns are linked to air pressure, which is linked to temperature.
3.The ice in cold places meltsIce melts when the temperature in a place rises above 0°C.
So world climates change.This affects all living things: Humans Birds, fish, &
other animals Trees, crops,
and other plants Even bacteria &
viruses.
OUR CHANGING CLIMATE - 3
Pollution of the atmosphere with carbon dioxide and other greenhouse gases is warming it up, raising world temperatures.Polar ice is melting, and by 2050 – if not before – there may be no ice at the North Pole in summer.Polar bears could become extinct, and if the polar ice sheets melt, sea levels could rise by up to 25m (82 ft.), drowning the world’s coastal cities.
Warming OceansThe oceans have absorbed much of the
increased heat due to global warming, with the top 700 meters (about 2,300 feet) of oceans showing a warming of 0.302°F since 1969.
Declining Arctic sea ice
Both the extent and thickness of the Arctic sea ice has declined rapidly over the last several decades.
Glacial retreatGlaciers are retreating almost everywhere around the world – including in the Alps, Himalayas, Andes, Rockies, Alaska and Africa.The disappearing snowcap from Mount Kilimanjaro, Africa seen from space.
Glacial retreat - 2
February 2001
June 2007
October 2007
Decreased snow coverSatellite observations reveal that the amount of spring snow cover in the Northern Hemisphere has decreased over the past five decades and that the snow is melting faster and earlier.
Shrinking ice sheetsThe Greenland and Antarctic ice sheets have decreased in mass.Data from NASA's Gravity Recovery and Climate Experiment show that Greenland lost 150 to 250 cubic kilometres (36 to 60 cubic miles) of ice per year between 2002 and 2006, while Antarctica lost about 152 cubic kilometres (36 cubic miles) of ice between 2002 and 2005.
Wildlife affected by global warmingHere are some animals affected by global warming:
GIANT PANDA
DOLPHIN TURTLE
POLAR BEAR
Wildlife affected by global warming - 2
TIGER HUMPBACK WHALE
Here are some other animals affected by global warming:
AFRICAN ELEPHANT
Did you know? There have been at least four Ice Ages in the Earth’s past,
when much of the Earth was covered in really thick ice. If Greenland’s ice sheet melts, sea levels around the
world will rise by 7 metres. In 2000, there were about 27000 polar bears on Earth and
over half were in Canada. Polar bears need ocean ice, to help them reach their main
food: seals. The average global temperature in 2000 was 15.6°C. A rise of 6°C above that would kill off billions of humans. Australia’s cattle and sheep give out about 3 million
tonnes of methane (a greenhouse gas) a year. The world gives out over 25 billion tonnes of carbon
dioxide a year, from burning fossil fuels.
Total world energy consumption
Global warming & its causes (in pictures)
Global warming & its causes (in pictures)
Global warming & its causes (in pictures)
THE POLAR BEAR
THANK YOU FOR YOUR
TIME
THE ENDBibliography:
DataWOW!EARTHgeog.2http://climate.nasa.gov/evidence/PicturesGoogle Imageshttp://climate.nasa.gov/evidence/
Done by – Karthik KosoorLusaka, Zambia