what do you think about global warming?

Answer 1

What does the greenhouse effect have to do with global warming?

The "greenhouse effect" refers to the natural phenomenon that keeps the Earth in a temperature range that allows life to flourish. The sun's enormous energy warms the Earth's surface and its atmosphere. As this energy radiates back toward space as heat, a portion is absorbed by a delicate balance of heat-trapping gases in the atmosphere—among them carbon dioxide and methane—which creates an insulating layer. With the temperature control of the greenhouse effect, the Earth has an average surface temperature of 59°F (15°C). Without it, the average surface temperature would be 0°F (-18°C), a temperature so low that the Earth would be frozen and could not sustain life.

"Global warming" refers to the rise in the Earth's temperature resulting from an increase in heat-trapping gases in the atmosphere.




What is causing global warming?









Scientists have concluded that human activities are contributing to global warming by adding large amounts of heat-trapping gases to the atmosphere. Our fossil fuel use is the main source of these gases. Every time we drive a car, use electricity from coal-fired power plants, or heat our homes with oil or natural gas, we release carbon dioxide and other heat-trapping gases into the air. The second most important source of greenhouse gases is deforestation, mainly in the tropics, and other land-use changes.

Since pre-industrial times, the atmospheric concentration of carbon dioxide has increased by 31 percent. Over the same period, atmospheric methane has risen by 151 percent, mostly from agricultural activities like growing rice and raising cattle.

As the concentration of these gases grows, more heat is trapped by the atmosphere and less escapes back into space. This increase in trapped heat changes the climate, causing altered weather patterns that can bring unusually intense precipitation or dry spells and more severe storms.



What is the best source of scientific information on global warming?










In 1988, the United Nations Environment Programme and the World Meteorological Organization set up the Intergovernmental Panel on Climate Change (IPCC) to examine the most current scientific information on global warming and climate change. More than 2,500 of the world's leading climate scientists, economists, and risk experts contributed to the panel's most recent report, Climate Change 2001: The Third Assessment Report.

Scientists from about 100 countries were involved in this new report—more than in any previous report and with greater participation from developing countries. These scientists reviewed all the published and peer-reviewed scientific information produced during the previous few years to assess what is known about the global climate, why and how it changes, what it will mean for people and the environment, and what can be done about it.

The Third Assessment Report is the most comprehensive and up-to-date evaluation of global warming. As the new benchmark, it serves as the basis for international climate negotiations.



Is global warming already happening?










Yes. The IPCC concluded in its Third Assessment Report, "An increasing body of observations gives a collective picture of a warming world and other changes in the climate system." The kinds of changes already observed that create this consistent picture include the following:

Examples of observed climatic changes



Increase in global average surface temperature of about 1°F in the 20th century

Decrease of snow cover and sea ice extent and the retreat of mountain glaciers in the latter half of the 20th century

Rise in global average sea level and the increase in ocean water temperatures

Likely increase in average precipitation over the middle and high latitudes of the Northern Hemisphere, and over tropical land areas

Increase in the frequency of extreme precipitation events in some regions of the world
Examples of observed physical and ecological changes



Thawing of permafrost

Lengthening of the growing season in middle and high latitudes

Poleward and upward shift of plant and animal ranges

Decline of some plant and animal species

Earlier flowering of trees

Earlier emergence of insects

Earlier egg-laying in birds



Are humans contributing to global warming?











In 1995, the world's climate experts in the IPCC concluded for the first time in a cautious consensus, "The balance of evidence suggests that there is a discernible human influence on the global climate."

In its 2001 assessment, the IPCC strengthened that conclusion considerably, saying, "There is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities."

Scientists have found significant evidence that leads to this conclusion:



The observed warming over the past 100 years is unlikely to be due to natural causes alone; it was unusual even in the context of the last 1,000 years.

There are better techniques to detect climatic changes and attribute them to different causes.

Simulations of the climate's response to natural causes (sun, volcanoes, etc.) over the latter half of the 20th century alone cannot explain the observed trends.

Most simulation models that take into account greenhouse gas emissions and sulphate aerosols (which have a cooling effect) are consistent with observations over the last 50 years.


How much warmer is the Earth likely to become?











The IPCC's Third Assessment Report projects that the Earth's average surface temperature will increase between 2.5° and 10.4°F (1.4°-5.8°C) between 1990 and 2100 if no major efforts are undertaken to reduce the emissions of greenhouse gases (the "business-as-usual" scenario). This is significantly higher than what the Panel predicted in 1995 (1.8°-6.3°F, or 1.0°-3.5°C), mostly because scientists expect a reduced cooling effect from tiny particles (aerosols) in the atmosphere.

Scientists predict that even if we stopped emitting heat-trapping gases immediately, the climate would not stabilize for many decades because the gases we have already released into the atmosphere will stay there for years or even centuries. So while the warming may be lower or increase at a slower rate than predicted if we reduce emissions significantly, global temperatures cannot quickly return to today's averages. And the faster and more the Earth warms, the greater the chances are for some irreversible climate changes.

Answer 2

Global warming is a farce created by idiot liberals like Al Gore as scare tactics. There is indisputable evidence to prove it does not exist. It is a natural occurrence for the world to experience changes in climate. The Sun also naturally changes in heat. As a matter of fact, The worlds average temperature is only 1 degree warmer than 100 years ago. Then again this spring has been the coolest one recorded in many decades. Must we worry about a phenomenon that has been purely fabricated?

Answer 3

Its an interesting question. Let me ask you this: why is the answer to this question so politically charged? I love the answer provided by Dennis Prager: (see source)

Now, let me weigh in:
There are three questions here:
1. Is there in fact global warming. Many people/scientists think yes.
2. Are we the cause? Much more difficult to prove.
3. Can we do anything about it if the answer to 2 is yes?

As a scientist, I can only gap in awe at the impossibility of both quantitatively understanding and measuring the climate. And yet - my left leaning friends have the utmost confidence that we are in big trouble. That seems to be the big issue here.

Answer 4

global warming is caused due to increase of presence of carbon di oxide in atmosphere.It can be harmful for the environment.
The latest example is amarnath shivlingam scientist believe it because of global warming.Late monsoon and more humidity are
are also because of global warming

Answer 5

It is without question the most tangible evidence of the degree to which the world's poor are at the mercy of the world's richest, and the lack of sympathy that the latter has for the former.

Answer 6

bcoz of inrease in pollution the temperature of earth is increasing this is known as Global warming

Answer 7

It's slowly but harmfully affecting in our life, summers are getting hotter and the winters are getting colder, natural disasters occurring frequently... but I'm sure we will die before the end of the world he he..

Answer 8

its kinda scaring me. MTV is trying to create a group that will help prevent it which is a gr8 way to get youth involved. itll happen in centuries tho. still i think we should recuce our air pollution and save our world from explodng r w/e.

Answer 9

I believe that in 30 years from now, we'll all be worried about the upcoming "Ice - Age".

Answer 10

It really makes me hot inder the collar!