Slashdot Mirror
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.'"
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!
"Sufferin' succotash."
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.
Floating ice will make no difference due to hydrostatic balance. The difference in sea level comes from warming of ocean water itself and resulting expansion, and melting of continental glaciers - Greenland probably most worrisome right now.
Energy: time to change the picture.
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!
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.
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%.
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.
Depending on where you work and where you live, driving can make the difference between a 30 minutes drive and a 2-3h public transportation journey. Public transportation zealots have to keep things in perspective. Politicians say people should use public transportation... but how many do so themselves on a regular basis?
:)
If I had a job with a ~100km round-trip, already owned a car and gasoline prices mysteriously tripled overnight, I would most likely do as you said and still keep driving - I wouldn't want to waste over 2h/day doing nearly nothing on public transportation when I have a [insert your favourite ~50MPG or better ULEV-compliant (sub-)compact car here] parked downstairs. Actually, I will be working at a place that is a ~100km round-trip starting in January and am seriously considering getting a Yaris - my previous job was in the same area and the ~2h it was taking to get there with public transportation would have driven me nuts, were it not for four-days weeks.
Instead of taxing gasoline, they should increase registration fees, tax unnecessary supersized vehicles with supersized engines and offer registration fee reductions for low emission, high efficiency, well-maintained, etc. vehicles down to (or even below) current rates. This way, people with average cars could work their way around the registration hikes/taxes by keeping their vehicles in perfect working order and by opting for more fuel-efficient and low-emission vehicles in the future. Many places already do things along those lines, some even go as far as offering subventions and tax deductions for hybrids.
Imagine a world where gasoline prices were artificially inflated to $20/gal... many people would not even be able to afford public transportation anymore, roads would be covered with soil and grass planted on them, riding horses would become popular again and this would not help the methane issue in the end. Cows and other farm animals are significant sources of atmospheric methane.
Mankind's influence on climate goes well beyond cars, people quickly forget that.
All this said though, I live in Canada and I would welcome an extra 5C from October through May. Since I am about 20m above sea level and live on a second floor, I am not particularly concerned about flooding
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.
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
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 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.
From one of the research papers (deltaD is what they use to measure temperature BTW):
The coupling of CO2 and {delta}D is strong. The overall correlation between CO2 data and Antarctic temperature during the time period of 390 to 650 kyr B.P. is r2 = 0.71. Taking into account only the period 430 to 650 kyr B.P., where amplitudes of deuterium and CO2 are smaller, the correlation is r2 = 0.57. Corrections for changes in the temperature and {delta}D of the water vapor source, which also affect {delta}D of the ice, have not been made yet. The strong coupling of CO2 to Antarctic temperature confirms earlier observations for the last glacial termination (9) and the past four glacial cycles (7) and supports the hypothesis that the Southern Ocean played an important role in causing CO2 variations.
Looking at their figures, there include data from the Vostok ice core which overs 0-415kyr BP and the correlation between CO2 levels and temperature is r2=0.7.
One gallon of diesel has 135000 Btu of energy, or 142 MJ. 10,000 gallons is 1.42 TJ. One acre is roughly 4046 square meters. So (presumably you're talking about annual yields here), each square meter of land will be producing roughly 350 MJ per year.
Peak solar power at sea level is 1 kW/m^2. Let's make the totally unrealistic assumption that the sun shines at peak brightness for an average of eight hours a day, no clouds or anything. That makes 28.8 MJ of solar input energy per day.
Huh. I'm rather stunned. Sure, it bespeaks a significantly impressive efficiency on the part of the algae, but there's likely no perpetual-motion tomfoolery here. Man, I'm going to grow a tank of greasy algae in my backyard!
Laws do not persuade just because they threaten. --Seneca
Wait, I can get more precise. Average values have been shown to be around 125 to 375 W/m^2. So, guessing an average of 250, we can get 7.2 MJ per day. Since algae doesn't care about seasons or anything like that, we can multiply that by the 365 days in a year to get 2.6 GJ per year.
So, the algae has to be around 13.3% efficient to get an energy yield of 10,000 gallons of diesel per acre. I have no idea if that efficiency is plausible or not.
Laws do not persuade just because they threaten. --Seneca
Three Mile Island is estimated to kill exactly one person.
Wikipedia has one Chernobyl estimate with 4,000 predicted deaths.
This is a technology that produces over 15% of the total world's electrical power, and during its lifetime, the total amount of estimated deaths to civilians is less then 5,000.
That's a decent safety record for a technology that is proven to be able to compete with traditional energy generation, and does not rely on how hard the wind blows or the sun shines to provide power. If you ignore obsolete technologies such as Chernobyl, nuclear has an even better track record.
To the moderator's that moderated the above comment "interesting", be aware that the 0.27% figure is fabricated. The same figure was rejected by Wikipedia as it was deemed "junk science". The source of the figure is a mining engineer's personal website (Monte Hieb) rather than a scientific journal or paper.
No, it's not informative.
There is a lot of land north of the Arctic circle, 99% of it is unpopulated. Arctic != 100% ice
If you mod me down, I *will* introduce you to my sister!
Which is why he included Interest Rates and home ownership...
The latter being one of the best economic indicators possible.
There are a couple cars that get in the 40mpg, but not many. There are laws of physics that make it really hard to get that high, without compromises that most people do not wish to make.
VW was getting over 50 mpg way back in the '70s with the Rabbit Diesel. Today they've got the Lupo 3 that gets over 80 mpg. Even the Passat TDI got 41 mpg while it was for sale in the US. A hybrid like the Honda Accord could easily get over 40 mpg (it already gets 37 on the highway), if they didn't feel the need to make it do 0-60 mph in under 8 seconds.
Downmodding is the refuge of the weak. Don't downmod, make a better argument!