Is methane gas contributing more to global warming than CO2?

[juju]

Hi,

Hers's my simple idea about global warming.

The suns energy is absorbed by the earth.

The Earth re-emits this energy as heat.

Human technology emits greenhouse gasses and produces more heat.

Green house gasses are increasing in the atmosphere.

The more CO2 and other greenhouse gasses in the atmosphere the more of this heat is reflected back to the Earth and warms the Earth and the lower atmosphere, while the upper atmosphere experiences cooling.

The global average temperature has risen about one degree F in the last century with larger increases in the higher latitudes.

Artic sea ice has thinned around 50% in the last century or less.

Glaciers are melting at a much higher rate today all over the world.

Seems like global warming is real to me.

juju

 

[Pengwuino]

Yes that is a very simple view of things. The suns energy is absored by the atmosphere but with higher concentrations of CO2, more energy is passing through. Human technology does emit these gases but no one can confirm that they are the acutal problem. There are a few CO2 pockets in the ocean that, if released, would make man kind's contribution to CO2 in the atmosphere seem like a mole hill compared to a mountain. Scientiests also do not know what is actually causing the warming and hte rise in temperature is much higher then that. So yes, very simple view on things.

 

[juju]

Hi,

Still this simple view points to the fact that at least some of the warming is due to human activity. How much is yet to be determined. Could be a high, medium, or low percentage.

juju

 

[Lil`SciWizGirl]

Global Warming is caused by the sun. Have you ever noticed that it gets hotter & hotter from summer to the next summer?

 

[Huckleberry]

Because the Earth is experiencing a 1 degree change in overall temperature in the last century does not seem like evidence to me of global warming caused by humans. The Earth goes through natural changes all by itself. Throughout history there have been times when the Earth has been very warm and has also been through ice ages. What causes these changes could be catastrophic events like massive volcanic eruptions or massive meteor strikes, or it could be a natural evolution of the planet. However, I think it would be foolish to not account for human interference. We do release greenhouse gases into the atmosphere and they do have some effect on the environment. The question is, how much of an effect? Juju is right about CO2 deposits in the oceans, and as the temperature rises more of this CO2 will be released into the atmosphere. Also, as we deforest the planet, especially the rainforests, we release CO2 captured in trees and reduce the planets ability to transfer this gas into oxygen. It's a problem that we should be concerned with whether we are directly responsible or not. We could be headed for a positive feedback loop that continuously increases global temperature. Then again...

 

[Phobos]

Have you ever noticed that it gets hotter & hotter from summer to the next summer?

no, there has not been a global linear temperature increase (although recent summers have included some of the hottest on record in some areas)

even if there was, how does that tie to your first statement that it's only sun induced?

 

[Phobos]

Because the Earth is experiencing a 1 degree change in overall temperature in the last century does not seem like evidence to me of global warming caused by humans.

Note that claims that anthropogenic global warming is occurring are not based on that observation alone. For example, the IPCC report includes graphs that show that the observational data best fit a climate model that includes both natural and anthropogenic effects (i.e., better fit than just natural effects alone or anthropogenic effects alone). As you said, the trick will be figuring out how much of the climate change is due to human activity vs. natural causes (the estimates on human input seem to range from 5% to 75%).

 

[Uno Lee]

Are the martian polar caps receding, year after year? Wouldn't that indicate if the sun is getting hotter, regardless of human intervention?

 

[Reshma]

Human technology emits greenhouse gasses and produces more heat.

Green house gasses are increasing in the atmosphere.

The more CO2 and other greenhouse gasses in the atmosphere the more of this heat is reflected back to the Earth and warms the Earth and the lower atmosphere, while the upper atmosphere experiences cooling.

Methane gas is a very good 'green gas' more effective than CO2. Methane is produced from human and animal excreta(especially cows in my country). Many industrial and chemical factories also produce this gas contributing to the 'Greenhouse Effect'.

 

[Sempiternity]

Here are some useful links for more information about global warming:

A Brief History of Climate Change
http://livescience.com/environment/ap_kyoto_today_050216.html

'Urgent need to cut greenhouse gases'
http://news.bbc.co.uk/1/hi/sci/tech/2349289.stm

The science debate behind climate change
http://www.cnn.com/2005/TECH/science/04/08/earth.science/index.html


It seems that governments and scientists are now recognizing global warming to be a serious threat to the future of humanity and are taking steps to rectify this important issue.

U.N. Study: Earth's Health Deteriorating
http://livescience.com/environment/ap_050330_ecosystem.html

Seeking solutions to a cooler planet
http://www.cnn.com/2005/TECH/science/04/15/earth.solutions/index.html

Kyoto Report
http://www.eia.doe.gov/oiaf/kyoto/kyotorpt.html

Text of the Kyoto Protocol (Treaty to cut greenhouse gasses)
http://www.cnn.com/SPECIALS/1997/global.warming/stories/treaty

 

[Ivan Seeking]

Two of the nation's premier atmospheric scientists, after reviewing extensive research by their colleagues, say there is no longer any doubt that human activities are having measurable--and increasing--impacts on global climate. Their study cites atmospheric observations and multiple computer models to paint a detailed picture of climate changes likely to buffet Earth in coming decades, including rising temperatures and an increase in extreme weather events, such as flooding and drought. The study appeared December 5 in Science as part of the journal's "State of the Planet" series. The coauthors--Thomas Karl, director of NOAA's National Climatic Data Center, and Kevin Trenberth, head of the Climate Analysis Section at the National Center for Atmospheric Research (NCAR)--conclude that industrial emissions have been the dominant influence on climate change for the past 50 years, overwhelming natural forces. The most important of these emissions is carbon dioxide, a greenhouse gas that traps solar radiation and warms the planet. "There is no doubt that the composition of the atmosphere is changing because of human activities, and today greenhouse gases are the largest human influence on global climate," they write. "The likely result is more frequent heat waves, droughts, extreme precipitation events, and related impacts, e.g., wildfires, heat stress, vegetation changes, and sea-level rise which will be regionally dependent." [continued]

http://globalchange.gov/

...The rapid rate of warming since 1976, approximately 0.2*C per decade, is consistent with the projected rate of warming based on human-induced effects. In fact, scientists now say that they cannot explain this unusual warmth without including the effects of human-generated greenhouse gases and aerosols...

...

PETER D. EWINS
CEO
UK Meteorological Office

DR. JAMES BAKER
Under Secretary
US National Oceanic and Atmospheric Administration

http://www.solcomhouse.com/metnoaa.htm

 

[jdlech]

There's no question that global warming is real. Even the oil industry accepts it as a matter of fact. http://www.scientific-alliance.org/news_archives/climate/bushcoversup.htm Once again, politics, rhetoric, and propaganda will probably win over facts, logic, and truth. The Scientific Alliance, btw, is partially funded by the oil industry. I found it interesting that they would report that article when it damages the reputation of one of their own advocates.

I remember watching a program on Nova a couple of decades ago. It included a graph of the average temperature derived from ice cores going back millions of years. What I found particularly noteworthy was that all the ice ages began after a brief, (100 to 1000 years or so), spike in global temperatures. First the spike, then the plunge, lasting thousands to tens of thousands of years.

I think the gaia theory is essentially correct, but there are limitations. Once a certain percentage of arable landmass becomes desert, something happens to the runaway greenhouse effect. It seems to plunge us into an ice age. For my money, it is this that we should be investigating.

 

[Phobos]

Methane gas is a very good 'green gas' more effective than CO2. Methane is produced from human and animal excreta(especially cows in my country). Many industrial and chemical factories also produce this gas contributing to the 'Greenhouse Effect'.

Methane is about 21 times* more effective than CO2 as a greenhouse gas, but CO2 is believed to play a larger role in Global Warming due to its much higher concentration (something like 1 ppm vs. 370 ppm on average, IIRC) and much longer life in the atmosphere...over 50% of the effect is from CO2.

* on a 100 year timescale...over longer timescales, the comparative effectiveness is less given that CO2 sticks around much longer than methane