Global Warming Question #2: Scientists claim that at many times in the past the earth has reached a...?

Question

temperature at which polar ice caps ceased to exist. Although the last time was millions of years ago (before the advent of humans), scientists now claim that deforestation and the burning of fossil fuels are bringing our planet to this same condition. If we are *certain* that these past events occurred naturally and were not the result of dinosaurs or other prehistoric earth life developing clear-cutting techniques and burning organic matter for fuel, why do scientists claim that the global warming that is occurring *now* is man-made rather than natural?

Answer 1

This has exactly the same answer as #1.

There have been natural climate changes in the past of course.

Until about 40 years ago, natural forces controlled the climate. At that point the peer reviewed data clearly show that man's emissions of greenhouse gases overtook natural forces as the most important thing.

http://www.globalwarmingart.com/wiki/Image:Climate_Change_Attribution.png

The data is why (note especially the key word - quantitative, science is about numbers, not "logical" arguments):

"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://www.ucsusa.org/global_warming/science/

Answer 2

During the time of global warming when the dinosaurs roamed the earth those massive creatures exhaled a lot of carbon dioxide which damaged the ozone layer just as we do with billions of people exhaling the same stuff. That's just one more take on man made global warming. Considering that we cut down forests that produce oxygen for us, eventually we will change the very air we breath and no longer be able to survive on this planet. That is my theory on why we are trying so hard to find a way to colonize other planets the same as our ancestors did when they came here from Mars.

Answer 3

Previous episodes of zero polar ice caps have all happened when the level of CO2 in the atmosphere was many times higher than it is now. So your question boils down to: how do we know that the current rise in CO2 is caused by us, and is not natural?

We know this because of isotopic analysis of the CO2 in the air. From this we can see that "old" carbon is combining with "young" oxygen, which can only be caused by the burning of fossil fuels.

http://www.realclimate.org/index.php?p=87

Answer 4

There are scientists on both sides of the issue. All scientists (well, over 90%) recognize that global warming exists, and that it's caused by both man and nature. But, they're about evenly split over what the primary cause is ... man or nature.

Answer 5

There's no question humans are responsible for deforestation and largely responsible for desertification. It's clearcut, doesn't require a lot of testing to see. I don't believe anyone disagrees.

There's also no question deforestation and desertification is responsible for [at least] many localized warming phenomena. Including the shrinking of the ice cap on Kilaminjaro.

It's also clear that pavement, rooftops, and many other man made features contribute to localized warming.

What isn't clear, at least to me, and to many reputable, responsible, competent scientists, is the extent to which these localized warmings are cumulative. The extent to which they're responsible for another phenomenon called global warming.

But, of course, the priests, lay people, and Inquisition of the Global Warming God will burn your house down for saying so. Don't say it.

Answer 6

UNFAIR! you aren't supposed to bring up FACTS in the debate about Global Warming!

You might actually contradict the religion of the global warming alarmists!

Heresy! Burn the witch!

Answer 7

They base this on the speed at which CO2 concentration is increasing.They claim that previous warming trends did not occur this rapidly. Unfortunately, they can only speculate on this. Ice core samples, tree rings, indirect measurements that rely on extrapolation to compare to the direct measurements of today.

Answer 8

for us it is natural everywhere you go you see construction and things like that so thats what makes it natural and with the dinosours they were around for millions and millions of years before that happened and we've only been around for like a couple million or somthing and that means that whatever we are doing is moving the process of the tempature cessing alot faster

Answer 9

It's more of a "we're speeding it along" kind of thing than a causing it kind of thing.