Evidence, shmevidence...to those that will not accept the idea of human activity affecting global warming, it's still just fake science.

I like multiple data checks on theories. like that one. Not that it matters from a policy point of view since we are not about to stop burning coal.
My solar power concentrator invention only affects natural gas consumption because solar power (like natural gas) is naturally a summer peaking power match. We don't affect baseload power coal consumption at all, so we don't affect the massive burned coal (CO2) and coal mine ventilation (CH4) greenhouse gases.
But then, every little bit helps. The massive floods on the Mississippi and other snow melt rivers will happen anyway, but maybe a few years later if we restrict greenhouse gases.

Interesting article in this month's Scientific American - the author asserts - that human activity has been changing the environment for over 8,000 years. He carefully does not, I think, argue for or against global warming as the end of the world but merely lays out the evidence he has. Summary: the developments that have allowed civilization to rise, have been altering our environment all along.

http://www.sciam.com/article.cfm?chanID=sa006&colID=1&articleID=000ED75C-D366-1212-8F3983414B7F0000

Has anyone thought of looking at when Spring Training begins? What if we learn that pitchers and catchers are reporting earlier and earlier every year, even if by an hour or so? Will that give us any insight into climate change? We'll need to figure in the change from 154 games/season to 162, but with high-powered math, I'm sure it can be done.

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I haven't seen this paper, but I've looked a bit at some of Barnett's earlier work. Don't you wonder how he can distinguish human-caused global warming from natural causes, just by looking at ocean temperatures? Why would human greenhouse emissions be any different from other forms of warming?

I think the answer is pretty surprising. It's not the warming signature that distinguishes human influence. It's the cooling.

Human-caused warming is not regional. Our greenhouse gases diffuse all over the globe and their effects are global. Looking at detailed ocean temperatures would not distinguish human-caused warming from other causes.

But he's not just looking at warming. If you read closely, you see that he's looking at cooling, too. He's looking at aerosols, which are particulate emissions that can shield the earth from the sun's rays and cause localized cooling.

Unlike greenhouse gases, the aerosol cooling effects do tend to be localized. They have their greatest impact when they are at relatively low altitude and are near or downwind of the sources of the aerosols, which are well known geographical locations.

In effect, I believe that Barnett compared a model based on sunshine with a model based on human activities, both greenhouse gases and aerosols. And the latter model worked much better in replicating the actual patterns of ocean warming. But it is really not the greenhouse signature you're seeing here, it is the aerosols which are producing the localized patterns which give him such a good match to the model.

In short, while his analysis does show a human impact on temperatures, it does not go to the heart of the question of the degree to which humans can and do influence overall global warming. I believe that question is still somewhat up in the air...

I certainly could be wrong, but it sounds to me like his methodology is question-begging.

[Why do you think so? A comment like this is unhelpful.]

"I believe that question is still somewhat up in the air..."

ahh, sadly no, I wish that it were, but it's not even close. The evidence has become overwhelming in the past few years. Business as usual isn't an option.

See http://www.realclimate.org/

>But surface temperatures in all six of the ocean basins he examined (the north and south Atlantic, Indian and Pacific oceans) have increased by about half a degree Celsius.

Lordy. Anybody want to take a stab at how much energy that represents?

How brave those who yet so bravely stand against such overwhelming evidence. Surely none braver have ever walked about this planet. None before have stood up to some, yea most, of the world's best scientists and mountains and mountains of evidence. Someday, the people of the world will no doubt thank these few brave souls for preventing action that might have reduced global warming. Perhaps we should commission their statues now and set aside display sites in capitals across the land.

zzz

This is actually the first real evidence that I have seen. Previous temperature data has been shown to be unreliable except for the Satellite data which doesn't indicate much warming. (and to a lesser extent the baloon data which confirms the satellite data). Have not yet read the Barnett stuff but it sounds interesting.

In any event, if the basic scientific relationship regarding CO2 emissions resulting in warming is true, you may as well throw out your snowshovel and buy and air conditioner. There is no feasible way to stop the warming.

Unstoppable? Yes. But action taken now would reduce the rate and lessen the extreme.

here is the link to the IPCC chapter on ocean temperature. Does seem to confirm the Barnett results as to some warming occuring. Also the energy effect.

http://www.grida.no/climate/ipcc_tar/wg1/058.htm

Levitus et al. (1997, 2000b) made annual estimates of the heat content of the upper 300 m of the world ocean from 1948 through to 1998 (Figure 2.11). The Atlantic and Indian Oceans each show a similar change from relatively cold to relatively warm conditions around 1976. The Pacific Ocean exhibits more of a bidecadal signal in heat storage. In 1998, the upper 300 m of the world ocean contained (1.0 ± 0.5) x1023 Joules more heat than it did in the mid-1950s, which represents a warming of 0.3 ± 0.15°C. A least squares linear regression to the annual temperature anomalies from 1958 to 1998 gives a warming of 0.037°C/decade. White et al. (1997, 1998b) computed changes in diabatic heat storage within the seasonal mixed layer from 1955 to 1996 between 20°S and 60°N and observed a warming of 0.15 ± 0.02°C or 0.036°C/decade.

X: You are too sensitive. The post from the heroic anonymous was surely eponymous.

But you should know that no attempts at humor are allowed on liberal message boards. We are too busy saving the world to try and -- you know -- enjoy an exchange or even condescend to the point of actually arguing our points to those who do not already share our view. Suffice to say, if you are not a liberal, then you are either a liar or stupid. Although that is true, it does get a bit tiring after a while.

In any event, with all this global warming, I'm much less worried about the budget deficit or potential stock market weakness heading into 2042.

on the other hand - from the AIP website

"Changes in the climate state of the North Pacific are obvious in the acoustic time series. The central North Pacific warmed considerably during 1999-2001 and the annual cycle in ocean temperature was relatively weak. But in early 2003, the central Pacific Ocean rather suddenly cooled and developed a strong annual cycle. Similar changes were observed using TOPEX/POSEIDON satellite altimetry. Satellite altimetry is a somewhat less precise measure of ocean temperature (as a column of water warms, sea surface height rises), but altimetry gives the larger geographic context to the changes that are occurring on the acoustic paths. These climate changes are probably normal variations in the Earth's climate system. After 6 years, no obvious sign of "global warming" is apparent. "

X: You are too sensitive. The post from the heroic anonymous was surely eponymous.

But you should know that no attempts at humor are allowed on liberal message boards. We are too busy saving the world to try and -- you know -- enjoy an exchange or even condescend to the point of actually arguing our points to those who do not already share our view. Suffice to say, if you are not a liberal, then you are either a liar or stupid. Although that is true, it does get a bit tiring after a while.

In any event, with all this global warming, I'm much less worried about the budget deficit or potential stock market weakness heading into 2042.

A different Chris:

Ah, let me have a try. This answer will be very very rough!

The surface temperature increase is 0.5 degrees, and goes to zero at about 700 m. I'm going to assume it drops linearly to zero, so that on average the top 700 m of the Earth's water is, on average, increases 0.25 degrees. (If, more reasonably, you assume that it falls off exponentially from the surface, with a scale height of say 350 m, you get an average temperature increase of 0.216, and you can just multiply my final answer by 0.86. If the scale height is 175m, you get an average increase of 0.122 degrees, and multiply my final answer by 0.49).

I don't know the surface area of the Earth's oceans, but let's say 75% of the Earth's surface is covered by them. That gives me a total amount of water of 4 pi r_e^2 * 700 m * 1027 kg/m^3 = 1.3e20 kg. (For physical properties of the water, this all takes place in the pycnocline, so I'm just going to assume everything has typical values of surface ocean water -- density = 1027 kg/m^3, specific heat of 3.89 kJ/(kg degC). )

The usual number given for total mass of the earth's oceans from what google tells me is 1.4e21 kg, so we've picked up 10% of the earths ocean mass at 700 m, which seems reasonable enough.

Specific heat of surface ocean water is 3.89 kJ/(kg degC), so the total energy required to heat up 700m of water by .25 degrees is 1.3e20 kJ. This is an enormous amount of energy -- equal to about 32,000,000 Megatonnes of TNT, or almost enough energy to raise the IQ of the trolls on this thread by 0.1 point, to 76.3.

As a sanity check, the Earth gets about 1400 W/m^2 from the Sun, and 1.3e20 kJ corresponds to about 1/4 of a day of that energy rate, which doesn't seem obviously absurd.

The paper by Barnett was "presented to the AAAS". I looked at Science Magazine, which is published by AAAS, but couldn't find the article. Where was it published, assuming it has been published? I would like to read the original article, not a version in the Economist, before judging its usefullness.

Ken:
Your suggestion is a good one. It has the added advantage of leaving an archeological mystery - like Easter Island Heads - for future species who might follow Mankind.

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The anti-climate change arguments seem to be that climate change not caused by humans has happened in the past. Well, that's true, but it does nothing to argue about whether it's manmade now. It seems a silly argument to say that all changes humans have made to the environment have had no effect.

The paper with these results has not yet been published. According to a friend of one of the authors, slides from the talk given at AAAS was available online for a few days, but the authors recieved sufficient threats they removed the slides and asked people do not distribute the slides. I haven't heard when the results will actually be published.

Jonathan,

Your calculation looks very useful. Although 1.3e20 kJ is a big number, converting it to about 6 hours of sunshine makes it sound small (small question, does that account for the fact that only half the earth is receiving sun at any one time?). So, why should I worry about an extra six hours of sunshine in the past 50 years? How does that sort of energy variability correspond to natural solar cycles?

I want to be worried but find your calculation making me remarkably relaxed about it.

John S.:

Don't be that relaxed. `Small' and `Large' have no meaning except in comparision to something relevant.

El Nino events screw up the weather system on the entire western coast of north and central america because a very localized region of the pacific has surface temperatures increase by about one half of a degree. In other words, half-degree changes can have enormous impact on the local climate. What effects can worldwide half-degree changes have? And, more troubling, since this isn't just a one-off event -- since the temperature isn't going down any time soon -- what are the long-term climate changes going to be?

Not a bad estimate; Levitus &co estimates 14.5x10^22 J, just over 10% more.

http://www.agu.org/pubs/crossref/2005/2004GL021592.shtml

The threat that scares me most, at the moment, is rising ocean acidity. (Google "ocean acidity" for plenty of articles on the issue. It's my understanding that it is at least partly responsible for the die-off of the Great Barrier Reef.) Taken to its logical conclusion -- dying phytoplankton and a reinforcing cycle -- it would seem to turn us into a very-slightly-cooler version of Venus.

I'd like to remind everyone that Daniel Davies has a bet open that climate change is real ... the test will be flood insurance rates in the Ruhr Valley in 20 years.

I dont know how many zeros he's good for, but I heard a story Munich Re wanted to lay off some bets.

Ian Whitchurch

Jonathan Dursi: I don't know how much of the daily sunshine the Earth retains, but in terms of heat it is probably more or less nothing, or the Earth would continuously heat up. So your figure is a bit misleading. It may represent much more extra sunshine than that.

I offer an alternative explanation: Some (not sure which part) of the sunlight energy is converted into chemical binding energy by plants producing biomass. Fossil fuels, including firewood, represent the remains of plants that lived past and present, and correspondingly stored "extraneuous" sunshine. All that energy is being quickly released by burning those fuels, and cannot be radiated off quickly enough.