What is global cooling exactly?

Question

Please back up your answer with scientific evidence or links to websites with evidence. Thanks!

And about what year will global cooling start to have effects?

I know that global cooling is cooling of the earth's climate, but how does it happen? I know about global warming, but not many people have talked about global cooling. Also, is it a natural change?

watch this

http://video.google.com/videoplay?docid=4499562022478442170&q=global+warming

Answer 1

Throughout the history of our planet there has been either global cooling or global warming. The dynamics are a bit complicated but the main reasons are atrributable to changes in heat ourput from the sun (solar variation) and changes in the way the earth moves (Milankovitch Cycles).

Solar variation over a short period of time is very small indeed. The main solar activity is sunspots which occur in 11 year cycles, the difference between minimum and maximum output is very small - just 1.3 Watts per metre squared per year, this compares to the average output of 1366W/m2/yr; so the difference is less than 0.1%.

Over periods of thousands and millions of year these small changes add up and can bring about global cooling and warming.

Milankovitch Cycles explian how the earth 'wobbles' about, there's three types - axial tilt, precission and eccentricity. The position of the earth in relation to the sun has a bearing on the amount of solar radiation it receives. If for example, the Pacific were to face the sun then a lot more heat would be absorbed than if Antractica faced the sun (the ice reflecting solar radiation back into space).

Atmospheric pollution also brings about global cooling and this is most noticable in the months and years following major volcanic eruptions. The sulphur dioxide particles reflect sunlight back into space. In 1991 Mount Pinatubo erupted and for the next few years temperatures fell slightly. In 1815 there was a much bigger eruption when Mount Tambora erupted in spectacular fashion and temperatures fell considerably, the following year became known as 'the year without a summer'.

Anthropogenic (manmade) global cooling has occured to an extent in the past for the same reasons that volcanoes cool the planet. In the first half of the 20th century factories and industry were churning out huge amounts of pollution and this reached a peak in the 1940's when there was so much pollution that it blocked sunlight and the earth began cooling. Following the deaths of many thousands of Londoners in 1952, Clean Air Acts were introduced, pollution levels fell and the global cooling was over.

No scientific evidence or links, it's something I've studied for a long time. However, I'm sure Wikipedia will provide much useful info.

Answer 2

Cooling is the loss of heat in a solid object in space. The sun is the only object that produces heat. If earth is covered by clouds, smoke etc. the radiant heat absorbed in the day time is held longer in the earth. If there is no cloud cover or smoke then the heat is lost at a faster rate. That is why the winter nights are so cold. Only the sun has the power to raise and lower the temperture of the Earth or Mars. The cooling and warming of the earth has been going on since the creation of the Earth and Mars. Man's puny effort to change the earths temperatue will be a dismal failure. Enjoy life now because as slow as the earth warms or cools will not effect anyone alive today. There is big picture here that Al cannot see because of all the $$$$$ being lavished on him by Hollywood.

Answer 3

Actually global cooling is already starting, particularly the last few weeks. We are already seeing this in colder temps across the country and entire globe.

What causes this? Sunspot activity. The sun goes through cycles of sunspot activity on an average of every 11 years or so.

While overall sunspot activity has been increasing for about a 1000 years...

See this website
http://news.bbc.co.uk/2/hi/science/nature/3869753.stm

... we still have ups and downs. The past 5-6 years have been on the up side and have been warmer than usual. Al Gore and the global warming alarmist would have us believe this is due to carbon dioxide. but we have been going through the high part of the solar cycle during that time. Right now we are starting to go through the low part of the solar cycle, so it is a lot cooler this year, and will probably continue to be cooler then next few years before another warming cycle occurs.

Don't worry, this isn't anything to panic about, it is part of nature that has been happening for millions of years and these fluctuations in solar activity will continue for millions more without destroying the planet.

Answer 4

To begin with, we do know that the sun is a star..a big one. At the beginning, it was said that the sun was white, then a bit yellow, orange, red orange, and be old into a red colour. When that time will come, the heat of the sun will cool down. Today, the sun has gone half of his way from its life. I think the day the sun will die soon, it will be the global cooling and the ice age may start. I learn this in high school...
http://www3.iptv.org/exploremore/energy/Energy_In_Depth/sections/sun.cfm
http://ask.yahoo.com/20040121.html
just google up sun lifespan and you'll get plenty of informations

Answer 5

(m)

Global cooling in general can refer to a cooling of the Earth; more specifically, it is a theory positing an overall cooling of the Earth's surface and atmosphere along with a posited commencement of glaciation. This theory never had significant scientific support, but gained temporary popular attention due to press reporting following a better understanding of ice age cycles and a temporary downward trend of temperatures from the 1940s to the early 1970s.

Answer 6

Its what brought on the ice age. No one is sure of the cycle!

Answer 7

exactly what the name implies. It will happen as soon as we stop polluting the earth.