What is your opinion on whether or not global warming is caused by human influence?

Question

Please support with details and facts, but also state your opinion

Answer 1

Scientists don't like to use the word "proof" because everything in science is subject to revision as new data comes in. But the case for human-caused global warming is about as strong as it gets.

1. If the Sun is causing the current warmth, then we're getting more energy, and the whole atmosphere should be getting warmer. If it's greenhouse, then we're getting the same amount of energy, but it's being distributed differently: more heat is trapped at the surface, and less heat is escaping to the stratosphere. So if it's the Sun, the stratosphere should be warming, but if it's greenhouse, the stratosphere should be cooling.

In fact, the stratosphere has been on a long-term cooling trend ever since we've been keeping radiosonde balloon records in the 1950's. Here's the data:
http://hadobs.metoffice.com/hadat/images/update_images/global_upper_air.png
http://hadobs.metoffice.com/hadat/hadat2/hadat2_monthly_global_mean.txt
http://cdiac.ornl.gov/trends/temp/sterin/sterin.html

2. If it's the Sun, we're getting more energy during the day, and daytime temperatures should be rising fastest. But if it's greenhouse, we're losing less heat at night, and nighttime temperatures should be rising fastest. So if it's the sun, the difference between day and night temperatures should be increasing, but if it's greenhouse, the day-night difference should be decreasing.

In fact, the daily temperature range has been decreasing throughout the 20th century. Here's the science:
http://ams.allenpress.com/perlserv/?request=get-abstract&doi=10.1175%2F1520-0450(1984)023%3C1489:DDTRIT%3E2.0.CO%3B2
http://ams.allenpress.com/perlserv/?request=get-abstract&doi=10.1175%2F1520-0477(1993)074%3C1007%3AANPORG%3E2.0.CO%3B2
http://www.bom.gov.au/bmrc/clfor/cfstaff/jma/2004GL019998.pdf

3. Total solar irradiance has been measured by satellite since 1978, and during that time it has shown the normal 11-year cycle, but no long-term trend. Here's the data:
http://www.ngdc.noaa.gov/stp/SOLAR/solarda3.html

4. Scientists have looked closely at the solar hypothesis and have strongly refuted it. Here's the peer-reviewed science:
http://www.pubs.royalsoc.ac.uk/media/proceedings_a/rspa20071880.pdf
http://www.mpa-garching.mpg.de/mpa/publications/preprints/pp2006/MPA2001.pdf

5. CO2 levels in the air were stable for 10,000 years prior to the industrial revolution, at about 280 parts per million by volume (ppmv). Since 1800, CO2 levels have risen 38%, to 384 ppmv, with no end in sight. Here's the modern data...
http://www.esrl.noaa.gov/gmd/ccgg/trends/
... and the ice core data ...
http://www.ncdc.noaa.gov/paleo/icecore/antarctica/law/law.html
http://www.ncdc.noaa.gov/paleo/icecore/antarctica/domec/domec_epica_data.html
http://www.ncdc.noaa.gov/paleo/icecore/antarctica/vostok/vostok_data.html
... and a graph showing how it fits together:
http://www.columbusnavigation.com/co2.html

6. We know that the excess CO2 in the air is caused by burning of fossil fuels, for two reasons. First, because the sharp rise in atmospheric CO2 started exactly when humans began burning coal in large quantities (see the graph linked above); and second, because when we do isotopic analysis of the CO2 we find increasing amounts of "old" carbon combined with "young" oxygen. Here are the peer-reviewed papers:
http://adsabs.harvard.edu/abs/1984JGR....8911731S
http://www.ingentaconnect.com/content/mksg/teb/1999/00000051/00000002/art00005
http://www.sciencemag.org/cgi/content/abstract/256/5053/74

So what's left to prove?

Answer 2

The amount of man made 'warming' is more of a very localized effect by pollutants seen as Smog. If you view a city on a calm day from about 20 miles you you will see a brown haze over the area - but when you are within the smog sometimes there is no sign of the 'Smog' you saw from a distance. I believe it is the darker particles as well as other pollutants that add to the warming effects.

More scientists have discounted the 'CO2 theory' because there is no way CO2 can reflect 1/2 the heat back to earth even if there was enough CO2 in higher atmosphere - which it is NOT proven there is enough CO2 at higher atmospheres to even impact our primary heat source.

The intelligent scientists are now reviewing the link with Sun Spots and Climate - sun spots emit radiations well beyond mere luminescence.
Web page: 'Rehabilitating Carbon Dioxide'
http://www.lavoisier.com.au/papers/Conf2007/R-Evans2007.html

Answer 3

Real. 75%-95% caused by us.

This is science and what counts is the data.

"I wasn’t convinced by a person or any interest group—it was the data that got me. I was utterly convinced of this connection between the burning of fossil fuels and climate change. And I was convinced that if we didn’t do something about this, we would be in deep trouble.”

Vice Admiral Richard H. Truly, USN (Ret.)
Former NASA Administrator, Shuttle Astronaut

Here are two summaries of the mountain of peer reviewed data that convinced Admiral Truly and the vast majority of the scientific community, short and long.

http://www.globalwarmingart.com/wiki/Image:Climate_Change_Attribution.png
http://ipcc-wg1.ucar.edu/wg1/wg1-report.html
summarized at:
http://www.ipcc.ch/SPM2feb07.pdf

It's (mostly) not the sun:

http://solar-center.stanford.edu/sun-on-earth/FAQ2.html

And the first graph above shows that the sun is responsible for about 10% of it. When someone says it's the sun they're saying that thousands of climatologists are stupid and don't look at the solar data. That's ridiculous.

Science is quite good about exposing bad science or hoaxes:

http://www.cs.cmu.edu/~dst/ATG/polywater.html

There's a large number of people who agree that it is real and mostly caused by us, who are not liberals, environmentalists, stupid, or conceivably part of a "conspiracy". Just three examples of many:

"Former Republican House Speaker Newt Gingrich challenged fellow conservatives to stop resisting scientific evidence of global warming"

"Our nation has both an obligation and self-interest in facing head-on the serious environmental, economic and national security threat posed by global warming."

Senator John McCain, Republican, Arizona

“DuPont believes that action is warranted, not further debate."

Charles O. Holliday, Jr., CEO, DuPont

There's a lot less controversy about this is the real world than there is on Yahoo answers:

http://www.worldpublicopinion.org/pipa/articles/home_page/412.php?lb=hmpg1&pnt=412&nid=&id=

And vastly less controversy in the scientific community than you might guess from the few skeptics talked about here:

http://en.wikipedia.org/wiki/Scientific_opinion_on_climate_change
http://www.sciencemag.org/cgi/content/full/306/5702/1686

"There's a better scientific consensus on this [climate change] than on any issue I know... Global warming is almost a no-brainer at this point. You really can't find intelligent, quantitative arguments to make it go away."

Dr. Jerry Mahlman, NOAA

Good websites for more info:

http://profend.com/global-warming/
http://environment.newscientist.com/channel/earth/dn11462
http://www.ucsusa.org/global_warming/science/
http://www.realclimate.org
"climate science from climate scientists"

Answer 4

There is more evidence to support the idea that CO2 does not drive climate than there is to say that it does. For example, in the ice cores it is well known that CO2 rises after temperature rises. Temperatures peak and then start to decline while CO2 levels are still increasing. 450 million years ago the CO2 levels were 15 times higher than they are now and the world entered a major ice age. The CO2 levels remained higher than they are now for duration of the ice age, which lasted for over 20 million years.

http://www.geocraft.com/WVFossils/Reference_Docs/The_Geologic_Record_and_Climate_Change.pdf

Answer 5

A persons opinion is just their statement on faith.

Science shouldn't require opinions. No one has an opinion of the speed of light, or about the distance the Sun is from the Earth. These are provable facts.

Man made "global warming" is a pseudo science built around a principal of beliefs. No one can prove global warming is real, as no one can prove if it will be warmer or colder 5 years from now.

Answer 6

GW may be caused to some degree by human factors, but natural factors have always had much greater impact on the climate than we are currently seeing, and we don't understand those well enough to know how much is natural and how much is man made.

Answer 7

Undecided due to insufficient empirical evidence.