Humanity Responsible For Current Climate Change

tehanu writes "Scientists working with Antarctic ice have found that the level of greenhouse gases is at the highest level in over half a million years. Carbon dioxide is 27% higher now than any other time over the last 650 000 years. Methane, an even stronger greenhouse gas is 130% higher. The period of time studied covers eight full glacial cycles including a time when the earth's position relative to the sun is the same as it is today. Other scientists have found that the annual rate at which the sea has risen since the industrial revolution is twice that of over the last 5000 years. It is predicted that by 2100 the sea level will be 40cm higher. These results provide strong evidence that human activity since the industrial revolution, rather than just natural processes, has strongly altered the world's climate. As one of the scientists involved in the research put it: 'The levels of primary greenhouse gases such as methane, carbon dioxide and nitrous oxide are up dramatically since the Industrial Revolution, at a speed and magnitude that the Earth has not seen in hundreds of thousands of years.'"

Comments

Hmm

[Overly Critical Guy]

I take issue with the conclusion of this submission headline, as there is plenty of evidence suggesting the possibility that we're not much of a contribution at all. I have yet to hear explanations for why temperatures actually DROPPED from the 1940s to the 1970s despite an increase in our use of automobiles and other gases. Not to mention that when you add the numbers up and take into account water vapor, mankind is only responsible for--wait for it--0.27% of the so-called greenhouse gases.

So, as Penn & Teller put it in their Bullshit! episode on the matter, we're still gathering data. So stop jumping to conclusions!

Re:Hmm

[apsmith]

Hope you're still there - here's the explanation:

the nowadays accepted interpreation [is] that the cooling was largely caused by sulphate aerosols

Those particulates that the clean air act got rid of in the 80's and 90's, caused cooling up to the 70's. They also caused smog, acid rain, lots of health problems etc. so it's a good thing we got rid of them. But the aerosols masked the warming trend for a while. Pretty well understood in the models.

Re:Hmm

[nathanh]

CO2 in the atmosphere is mainly volcanic in origin, accounting for 97% of the CO2 found in the atmosphere, most of which travels to the oceans. Estimates at CO2's effectiveness as a greenhouse gas vary, but are generally around 10-100 times lower than water weight for weight, leaving a "net" greenhouse effect of man-made CO2 emmissions at less than 1%

The precise figure is around a 0.27% contribution from mankind.

It's usually considered good form to cite the quote, so we can see who said it and what evidence they had for the claim. As it is, the power of google comes to the rescue and I find the original source for your above quote is Wikipedia::Global_warming_controversy which in turn links to Monte Hieb's personal website.

Well, that's OK, a personal website isn't necessarily a bad source of information. We shouldn't be concerned that Mr Hieb has no education in climatology, isn't a scientist nor a doctor, doesn't have any peer reviewed papers, doesn't do research nor experiments, and isn't cited by anybody except the enthusiastic gunslingers of the "global warming is a myth" brigade. All of those details are irrelevant if Mr Hieb gets his facts right. Unfortunately he hasn't got his facts right either. If you google his name the first hit is somebody ripping apart Mr Hieb's claims. You immediately find out that Mr Hieb redefines existing scientific terminology. Tut tut, that's not a good sign.

Here the authors redefine "global warming". While the term usually refers to human caused warming, they use the term to include natural changes as well. A similar redefinition has been used with other environmental problems such as ozone depletion and acid rain. ("Global warming" has been increasingly replaced by the more accurate and inclusive "climate change"). -- http://info-pollution.com/chill.htm

That page goes on further to refute the "facts" asserted by Monte Hieb. Somebody once tried to get Mr Hieb's claims into other pages on Wikipedia but those attempts were ... uhhh... rejected. Here's a comment that accompanied one such rejection.

But to turn to the GHG page, which is what this is really about. C says: objects and deletes all sources and documentation that state anything he disagrees with. This in turn is a ref to him trying to insert a dubious value of 95% for the greenhouse effect of water vapour, based upon this source: http://www.clearlight.com/~mhieb/WVFossils/greenho use_data.html. That page isn't a source: its just some bods pet page. The numbers on it are wrong. All this has been, is being, discussed on the talk page of greenhouse gas. -- http://en.wikipedia.org/wiki/Wikipedia:Requests_fo r_comment/William_M._Connolley

That 95% figure (which is intrinsically linked to your 0.27% figure) isn't supported by the data. The best guess figures are between 60% and 70%. If you continue to google Mr Hieb's name you'll find that pattern repeated over and over; Mr Hieb uses incorrect values, redefines terminology and eventually arrives at incorrect conclusions. But who is Monte Hieb?

Assessment: This example is the crux of the matter, IMO, because it reveals the source of Cortonin's information. The website referenced is the personal website of Monte Hieb. A quick review of Hieb's credentials reveals that he has worked as chief engineer for the West Virginia Office of Miner's Safety. He has done some geological survey work on fossils. There are extensive links from Free Republic's website to Hieb's. WMC refers to him as "just some bod," but cle

Re:Good

[reiggin]

Bush didn't sign the Kyoto protocol... blahblahblah...

And neither did Clinton. Oh, and no one on either side of Congress voted for it, either. Sorry for this temporary insertion of non-slanted facts. You can resume your regular misinformed spin now.

Re:Solar Activiity is at its highest levels since

[e_lehman]

You're a bit off on your timescales. The southern icecap on Mars is melting because it is spring there:

From NASA:

Like Earth, Mars has seasons that cause its polar caps to wax and wane. "It's late spring at the south pole of Mars," says planetary scientist Dave Smith of the Goddard Space Flight Center. "The polar cap is receding because the springtime sun is shining on it."

Similarly, the warming on Pluto is also apparently seasonal (though its seasons are long, of course). From Space.com:

Pluto's atmospheric pressure has tripled over the past 14 years, indicating a stark temperature rise, the researchers said. The change is likely a seasonal event, much as seasons on Earth change as the hemispheres alter their inclination to the Sun during the planet's annual orbit.

When scientists worry about global warming on earth, they're not just griping about the arrival of spring!

Re:No! God did it!

[frogstar_robot]

Artic land rush...... now you know what the plan is.

Antarctic land rush. The artic pole will be nothing but a chilly sea if the ice melts. Hardly any land mass up there to speak of. Antarctica has a continental landmass underneath it's cap.

Re:Links

[blamanj]

I don't know if I find that site particularly credible. For one thing, he claims that the Irish Potato Famine was caused by climate change, when in fact it was caused by a fungus.

In addition, other sites suggest that water vapor accounts for much less of the greenhouse effect, 60% according to these folks, and the Wikipedia offers anywhere from 36% to 70%.

Re:No! God did it!

[(negative video)]

Use real wood people, you're not hurting the environment by doing so, ...

Log-in-a-fireplace burning produces extremely dirty smoke. I've heard, though, that the controlled wood pellet burners with catalytic converters are pretty clean.

27% of ALL CO2 not 0.27%

[tehanu]

A common comment I see here is:

- humans only contribute 1% of the CO2.
- hence a 27% increase is a 0.27% increase

This is NOT what the studies show. It is 27% higher than ANY CO2 level in the past 650 000 years. This includes BOTH natural processes and man-made processes. It does not distinguish between the two sources. I've seen their graph. There is a nice cycle with greenhouses gases, and temperature with temperature slightly lagging behind C02 levels. This is the natural cycle that people talk a lot of. Who knows what causes it. Then suddenly, in recent times, the cycle is destroyed and there is a sudden upsurge in C02 levels near present times. It is very clearly anonomalous.

Don't forget the 1% is someone's guess about how much mankind contributes.

How about this?

[Goonie]

This article quotes figures from the US government suggesting that you can produce 7.5 billion gallons of biodiesel on 500,000 acres of land. That works out to about 15,000 gallons per acre, per year. The Wikipedia article (which is actually well-referenced, but doesn't include references for those specific figures) was right. Why can algae do so well? Because it grows really, really fast, and a huge fraction of the plant is actually oil.

However, it's not as simple as that; the technology hasn't been developed to actually farm the stuff on a commercial scale, but there are people working on that. The first test deployments are by these guys, who are using the exhaust systems from conventionally-fired power to provide nutrients for the algae and prevent the release of CO2 and NOx into the atmosphere.

But yes, in the future you might well be able to grow all the fuel for your car in your backyard.

No gradual increase

[tehanu]

It doesn't gradually increase. As I said in other posts, the results show a clear cycle in greenhouse gas levels and temperatures. This is the natural cycle. Then close to the present time, there is a massive almost delta-function like spike in the greenhouse gas levels that elevate the gas levels far beyond any other point in the graph. It's so sharp it's practically vertical. And the delta function occurs in all three gases measured (CO2, methane, nitrous oxide). There are no similar events in any of the other results from the last 650 000 years. There are other spikes but they are a magnitude smaller and occur over a longer time scale.

If you're really interested

[MannyOHara]

If you're really interested in what people who know what they're talking about on this issue have to say do the research. One place already mentioned by other posters is http://www.realclimate.org/ and another is http://www.begbroke.ox.ac.uk/begbroke/Display/page /Climate.Basics.html which is the Oxford University site Climate Basics. RealClimate includes information on pretty much every objection that some of the people here have posted. They also explain a lot of the misinformation that's out there and also take suggestions on subjects to post about. It's definitely interesting to see here how many technically knowledgable people aren't really scientifically literate.

Re:No! God did it!

[IdleTime]

No, it's not informative.

There is a lot of land north of the Arctic circle, 99% of it is unpopulated. Arctic != 100% ice