How do scientists determine that global warming is occurring?

Answer 1

We know that one of the worlds biggest lakes has dried up,about 5 spieces of animals go extinct each day,there are over 200 powerplants and factories in the world[see question:if global warming is happening how is it warming the planet.

Answer 2

Life exists on our planet because of global warming.

There are glacial records to show that the planet has been warming (with a few cycles in between) almost non-stop for thousands of years.

And regarding recent man-made global warming, satellites and ground measurements show conclusively that global temperatures are rising rapidly. The ten hottest years on record have all occurred since 1997. The years 2010 and 2005 tied as being the hottest on record.

Evidence that the layman can examine comes in the form of glaciers. Look at the history of any glacier and you will find photographic evidence that they have receded over recent years.

Answer 3

The facts speak for themselves. The year 2010 had the warmest global average temperature on record, fractionally warmer than 2005 and 1998, but as the difference is slight, the three years are regarded as the equal hottest. The past decade was the warmest since instrumental measurement began in 1850, and the ten warmest years since 1850 have now all occurred since 1998.

The Global Warming being referred to is the current accelerated warming, not the natural cycle of the planet's climate.

For proof, simply look towards peer-reviewed studies on sea levels, CO2 levels, Arctic ice levels etc.

The majority of the world's climate scientists agree that the temperature of the world has been gradually rising for the past 150 years, since the time man started seriously burning coal and oil.

NASA (National Aeronautics and Space Administration) states on its website that the measurable evidence is in the following:

• Sea level rise
• Global temperature rise
• Warming oceans
• Shrinking ice sheets
• Declining Arctic sea ice
• Glaciers retreating
• Extreme Climate Events
• Oceans become more acidic

See the NASA weblink below.

Answer 4

You can tell because there have been changes in the weather:

• increases in the intensity and duration of tropical storms and cyclones
• more recent heat waves
• increase in lands suffering drought

You can tell because there have been Glacier retreat and disappearance

• mountain glaciers and snow cover have decreased in both northern and southern hemispheres

You can tell because there have been changes in the Oceans:

• Increased levels of carbon dioxide (CO2) in the air has caused the oceans to become more acidic

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There has been a 4% loss of ice in the Northern hemisphere and an ice gain in the Southern Hemisphere.

We have much evidence that suggests there is global warming taking place for at least 10,000 years. The total warming is apparently over 10 degrees C. We can witness this through retreating glaciers and vegetation changes.

Recently we can determine that the planet has warmed over 0.1 degrees since 1938 by studying satellite images that instantly show us worldwide temps.

There has definitely been cooling since the Medieval warming period also. Most science experts agree that the temps in 1400 were probably as much as 2 degrees C warmer then today.

Answer 5

The unprecedented reduction of the arctic ice cap, permafrost and mountain glaciers are sure signs that global warming is occurring. Historic records show glaciers around the planet are reducing. Further, ocean levels have been documented as rising several inches, which does not sound like much but has already made several low-lying islands uninhabitable.

Anyone who remembers the phantom pursuit of the "Northwest Passage" recalls that trying to find a sea route to Asia from Europe through a waterway across or around North America failed because no river spans between the Atlantic and Pacific oceans, and because when you go too far north, you run into the 'permanent' Arctic Ice Cap. The Arctic Ice Cap has existed for millions of years, but at the current rate of melting, will disappear entirely within a decade or two; it has already receded to the point that much of the Eurasian and North American north Coastlines are ice-free much of the year where they had never been so before.

Glaciers in mountains serve as reservoirs that let rivers run, even when there are no rains to actively feed them. On every continent except Antarctica, the glaciers are disappearing and that is both a sure sign of global warming and the mark of a coming calamity; there is reduced drinking water available, and as more glaciers melt away, will continue to be reduced drinking water available.

The evidence is already clear that global warming is already occurring.

Answer 6

it is obvious that it is a problem because if you see pictures of the artic nowdays it shows that global warming is a bad thing because it is m,ealting down all the ice.

answered by a 10 year old

Answer 7

Scientists can prove that global warming is really happening. We can ask the scientists. We can even ask the scientists to explain their evidence.

Scientists rely in part on accurate temperature measurements taken around the world since 1850, to establish an annual average global temperature. Some instrument readings have been adjusted for the urban effect, which could give a false high reading for temperature increase, yet rising temperatures are still evident. With natural fluctuations, the average global temperature has been trending upwards since temperature records began, with the trend becoming increasingly marked since the 1970s.

Another indicator is rising sea levels. Sea levels have risen by twenty centimetres over the last hundred years, due to melting of the ice caps and glaciers and the expansion of ocean water. This is a clear sign of a long-term rise in global temperatures.

Answer 8

ice samples help determine the change of greenhouse gasses and temperature, among other things from time to time.

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On the Discovery channel you can find scientists and photographers who have taken pictures of the polar icecaps every day for years just to prove global warming is actually happening. Hop on the net and go to Discovery Channel and search for these videos, you won't be sorry. How much information do some people need, it is going on and doesn't show any signs of stopping. Please use electric or natural gas.