Evidence that global warming is caused by humans?

Question

in points p[lease

not long paragraphs

Answer 1

There is evidence that man-made activity is one factor in global climate change, not more or less. The question is why not do everything in our power to make a safe enviorment for ourselves and children

Answer 2

My page that was linked by Ken above is a good "bulletin point" summary, but the IPCC AR4 report is your best bet (particularly the chapter on detection and attribution).  Concerning the post on the relative contributions of the greenhouse effect, this is also wrong.  See Kiehl and Trenberth 1997 (it's about 2/3 water vapor to 1/3 CO2); the 95% is nowhere in any real academic source.  There are other reasons why water vapor does not swamp the effect of CO2, but off-topic here, though you can discuss that at my site.

chris

Answer 3

Bob & Dana - you are evading the question.  You each get an "F" for your sloppy non-answers.  Keep in mind "I don't know" is an acceptable response!

1. What % of the total greenhouse effect is due to humans? (0-100%)?

2. Your friend Dr. James E. Hansen says that "The paradox that this result presented was the contrast between the awesome forces of nature and the tiny 2 watt/sq.meter [impact of humanity]".

Then then says "small forces (humans), maintained long enough, can cause large climate change."

How?

My answer is that the total greenhouse effect by humans is < 0.3%.  

Source               % of All           % Natural          % Man-made

Water vapor    95.000%         94.999%            0.001%

CO2                  3.618%            3.502%             0.117%

CH4                  0.360%            0.294%             0.066%

N2O                  0.950%            0.903%             0.047%

CFC's, etc.      0.072%             0.025%             0.047%

TOTAL             100.00%           99.72                0.28%

EDIT: Sorry, Bob - you link news stories.  Hardly primary sources.  You get a second "F".  "small forces (humans), maintained long enough, can cause large climate change."  HOW?

It's not the end of the world, it's just the end of your funding.

Answer 4

It's really too complicated for bullet points.  I wrote an entire wiki article on the subject, linked below.

*edit* jim and almost - this is not your question.  I will be happy to answer your questions, but not here.  Stop trying to distract from the question that was asked.

Answer 5

I don't think you can but since Dana provided his link as an answer I felt compelled to respond to it.

Dana provided good evidence for not trusting everything you read in Wiki.

To take an example, He wrote:

"It's important to note that while past climate changes weren't initiated by CO2, carbon dioxide did play a big role as a "feedback".  .....CO2 then accumulated in the atmosphere, causing the planet to warm further (since it's a greenhouse gas), causing the oceans to release more CO2, etc. etc.

This oversimplification suggests that CO2 is significant as a feedback mechanism.  This is of course what alarmist rely on people to accept.  The problem is that if the feeback mechanisms were as powerful as they suggest,  there wouldn't be any cycles to begin with.  This over-emphasis on feedback of CO2  is nothing more than an attempt to try to blame humans on any climate change.

Answer 6

Here's a nice little summary:

The Scientific Basis of Anthropogenic Global Warming

http://chriscolose.wordpress.com/2007/12...

Answer 7

-Cars!

-Factories!

Humans are the ones releasing CO2. Cars release gas, which increases carbon in the air. G.w is all human activity.

Answer 8

Sorry, this CAN'T be done in bullet points.  All you can do with those is make unsubstantiated statements, like those above.  If you want to actually know about this, there is no substitute for doing the work.   As a matter of fact the real proof is in the links.

This is science and what counts is the data, not people's intuition.

"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/Ima...

http://ipcc-wg1.ucar.edu/wg1/wg1-report....

summarized at:

http://www.ipcc.ch/pdf/assessment-report...

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

http://www.worldpublicopinion.org/pipa/a...

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_...

http://www.sciencemag.org/cgi/content/fu...

EVERY major scientific organization has issued an official statement that this is real, and mostly caused by us.  The National Academy of Sciences, the American Association for the Advancement of Science, the American Institute of Physics, the American Chemical Society, the American Geophysical Union, the American Meteorological Association, etc.

Good websites for more info:

http://www.nrdc.org/globalWarming/f101.a...

http://www.ucsusa.org/global_warming/sci...

http://www.realclimate.org

"climate science from climate scientists"

http://environment.newscientist.com/chan...

EDIT - "What % of the total greenhouse effect is due to humans? (0-100%)?"

Small.  But close to 100% of the recent INCREASE in the greenhouse effect that's causing warming is due to us.  The proof is overwhelming, but too long for a Yahoo answer.  It's detailed here:

http://environment.newscientist.com/chan...

and

http://environment.newscientist.com/chan...

Answer 9

None.

But there IS lots of evidence that it is a naturally recurring cycle.

Global warming has been documented with ice cores dating back tens of thousands of years. What is NOT real is the quackery that humans caused (or can even affect) global warming.

The scare tactics being perpetrated upon us are only a money/power grab scheme by bottom-feeder politicians accompanied by their so-easily-led sheeple who take their prattle, even their movies, as hard science.

To find that my statement above is true, follow the money. See just who it is who will profit from the carbon offset, carbon tax, & etc.

Here is truth about global warming:

Global warming is one-half of the climatic cycle of warming and cooling.

The earth's mean temperature cycles around the freezing point of water.

This is a completely natural phenomenon which has been going on since there has been water on this planet. It is driven by the sun.

Our planet is currently emerging from a 'mini ice age', so is

becoming warmer and may return to the point at which Greenland is again usable as farmland (as it has been in recorded history).

As the polar ice caps decrease, the amount of fresh water mixing with oceanic water will slow and perhaps stop the thermohaline cycle (the oceanic heat 'conveyor' which, among other things, keeps the U.S. east coast warm).

When this cycle slows/stops, the planet will cool again and begin to enter another ice age.

It's been happening for millions of years.

The worrisome and brutal predictions of drastic climate effects are based on computer models, NOT CLIMATE HISTORY.

As you probably know, computer models are not the most reliable of sources, especially when used to 'predict' chaotic systems such as weather.

Global warming/cooling, AKA 'climate change':

Humans did not cause it.

Humans cannot stop it.

Answer 10

Humans exhale carbon dioxide and produce body heat.

Answer 11

"Evidence that global warming is caused by humans?"

NONE exists...... Period!