EnviroLink Forum

Human activities have led to large increases in heat-trapping gases over the past century. The global warming of the past 50 years is due primarily to this human-induced increase. Global average temperature and sea level have increased, and precipitation patterns have changed. Human “fingerprints” also have been identified in many other aspects of the climate system, including changes in ocean heat content, precipitation, atmospheric moisture, plant and animal health and location, and Arctic sea ice.

How do you know there haven't been warming trends of the same magnitude, over the same amount of time, at some point in the past? Given the relative insignificance of 50 years with respect to climate change and the sheer level of noise in temperature observations, how do you arrive at this conclusion?

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TANG SOO!

because that is what they are told.

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sammyds world

Watch out where the huskies go, don't you eat that yellow snow

The alarm isn't over a few degrees of temp change but rather a warning of perhaps irreversible damage to our environment caused by us. Global warming and ice ages have occurred in the past but the right now the science is telling us of our role in causing damage to the climate equilibrium and indirectly to the ecosystems of our planet.

Well, you are not telling us something that we don't already know, and know in a lot more detail.
For example; the ice and ocean sediment core data going back over a million years shows an average of 230 PPM of CO2 with variations plus or minus 50 PPM (look it up yourself!!). Then in the last century this has ACCELERATED upward to the present 386 PPM and still accelerating upward. The "hockey stick" so hated by denialists was proven to be true. Mann and others have shown the latest round of denialism and stolen emails are bunk toward debunking AGW.
You are right dalani, the alarm isn't over the few degrees of now(actually more than a "few" degrees in the Arctic), but what will happen in the next several hundred years to the biosphere. Oceanic warming from atmospheric warming could explosively release methane(with as little as 1.5*F rise--look it up yourself) from the various depths in a self sustained global warming beyond life adaptability abilities of most species. All from the start of global warming caused by human activities.

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"With every decision, think seven generations ahead of the consequences of your actions" Ute rule of life.
“We do not inherit the earth from our ancestors; we borrow it from our children”
― Chief Seattle

Yes, and variation greater than 50, and variation lesser than 50. Is the distribution normal over the time frame referenced?

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TANG SOO!

Peruse to your heart's content:
http://www.realclimate.org/index.php/data-sources/

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"With every decision, think seven generations ahead of the consequences of your actions" Ute rule of life.
“We do not inherit the earth from our ancestors; we borrow it from our children”
― Chief Seattle

There are quite alot of links beyond yours here. Would you happen to know the general direction, if not specific location, where I might find temperature data (or some measure that correlates with it) prior to the 1800's?

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TANG SOO!

If I may put in my two-pennoth, try this...

http://www.esrl.noaa.gov/psd/data/usclimate/

Thanks. Had to do some digging, but I found exactly what I was looking for. Still only 2000 years, but closer:



http://www.ncdc.noaa.gov/paleo/globalwa ... olast.html

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TANG SOO!

I see the graphs are from 2006 and not the report for the last 2000 years from a few months ago. Still, that darn "hockey stick" of exponential change is there. The middle link in my post above is Mann's response to the so-called "climate-gate", from November 28 of this year, with more vindication of the "hockey stick".
The question is; can we stop the AGW and, if not reverse it, hold it to a minimal amount, and get off the exponential trend?
It also has a parallel with human overpopulation, because if we can't also stop that, we can't stop thermageddon.

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"With every decision, think seven generations ahead of the consequences of your actions" Ute rule of life.
“We do not inherit the earth from our ancestors; we borrow it from our children”
― Chief Seattle

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" thermageddon "...........now that is appropriate................great word, is it 'yours' ?

What if every man,woman,child planted a tree?
A single tree per person
do the math - approx.: at ten year maturity a tree can sequester one ton of Co2 emissions.

Well the job got done
http://www.unep.org/Documents.Multiling ... =en&t=long

should be annual..

No. It is the title of a book I read some time back. I thought the projections in the book were absurd, but the reality is that AGW HAS been accelerating faster than the worst case scenarios.
I googled "tons per year of CO2 by humans", and it verified the max was 281 PPM in the past 650,000 yrs. of ice core data. Humans put out 150 times the average volcanic output of CO2, knew that, too. The annual amount put out by humans of CO2 is now 24 Billion tons. The planting of 7 billion trees is laudable, but at a ton each of CO2 sequestration in their lifetime, it is obviously much lower than the human output. We can't plant 170 times that many trees, so the vast reduction needed must come from stopping fossil fuel use 70 to 80% and totally stopping slash and burn and swamp draining agriculture. All within a decade, or the eventual temps in 2050 will be enough for the ocean CH4 hydrate releases to go self-sustaining. Then "thermageddon", after the couple hundred years it takes for the oceans to warm and "turn over" the CH4. There probably won't be many people left by then.
I sure hope the powers that be in Copenhagen take all of this into account. Most people will scream and cry when their fossil fuels and traditional ecological waste are vastly reduced. Certainly, the world economy must change to steady state from growth only, and that change will also be painful. To start having to pay true costs will be very tough. So will having to pay for the mistakes of others now dead. The fossil fuel addiction will be very hard to kick.

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"With every decision, think seven generations ahead of the consequences of your actions" Ute rule of life.
“We do not inherit the earth from our ancestors; we borrow it from our children”
― Chief Seattle

If Al Gore brings out a video you bet your cotton socks it is to appease his money mad boyfriends. Climate change has been going on since the earth spun. So forget it friend and stop being brainwashed into paying more taxes.