Climate Change - What If It's Already Too Late? - New Statesman Article

[hatrack]

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"All the efforts of the climate-change panel, all the international conferences and protocols, all the green campaigning, are based on the assumption that, if we act now, the worst can be avoided. Although some global warming is already inescapable - temperatures will continue to rise for many years, and there is no power on earth that can stop them - we assume, none the less, that it is not too late; if we do the right things within the next couple of decades, temperatures will eventually stabilise.

But what if this is wrong? What if global warming is already unstoppable and is now accelerating uncontrollably? What if we have reached the point of no return and there is nothing we can do except wait for the end? Scientists are naturally cautious people, but a growing number fear that this may be the case. One ominous indicator comes from a US atmospheric sampling station 3,000 metres up on the northern flank of the Mauna Loa volcano in Hawaii. Since the 1950s, this station - and dozens of others dotted around the globe from Alaska to the South Pole - have recorded a steady increase in carbon-dioxide concentrations. The average year-on-year rise is 1.5ppm. Over the past two years, the rate of accumulation has doubled - to nearly 3ppm. This could mean that the rate of fossil-fuel burning has doubled - but it hasn't. The alternative explanation is that the biosphere "sinks", which used to absorb carbon, have suddenly shut down.

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How seriously should we take these warnings? It must be emphasised that, while scientists are now virtually unanimous about the reality of man-made global warming - new evidence published in Nature that the troposphere, the lowest level of the atmosphere, is warming at roughly the same rate as the earth's surface has removed the last doubts - they are far more cautious about suggestions that it is already moving out of control. The increase in carbon-dioxide concentrations detected by the Hawaii station, says Pieter Tans of the US National Oceanic and Atmospheric Administration, may not continue. In warmer years, he explains, the rate of bacterial decomposition in the ground speeds up, and more carbon is released from soils. Over more than a few years, he says, ecosystems adjust. However, his colleague Ralph Keeling, while agreeing that the recent change "might not be such a big deal", points out that "there is no past period where the average carbon accumulation has stayed this high". Another expert on the carbon cycle - who was prepared to speak only on condition of anonymity - said: "We simply don't have a way to tell from just one year if a positive feedback is kicking in. But if it was happening, this is what it would look like."

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If such an event happens again, the only certainty is that there will be no warning. And yet, the danger signs are already all around: 2003 was the second-warmest year on record. Last summer's heatwave across Europe was so far off the normal statistical scale that climatologists logged it as a once-in-10,000-years event. Sea-level rise is accelerating, according to the latest satellite measurements. And last month, a truly unprecedented weather event occurred. Hurricanes were thought to be an entirely north Atlantic phenomenon. But on this occasion an Atlantic hurricane formed south of the Equator and struck Brazil with 90mph winds. Tropical meteorologists were so baffled that they had no idea what to call it, and hurricane monitoring systems may now have to be extended a thousand miles further south. So is there any hope of persuading politicians to treat global warming with the urgency it requires? Perhaps so, now that the story has reached Hollywood, with the disaster movie The Day After Tomorrow due out this summer. Unfortunately, the events in the film are premised on an effect of global warming that remains contentious among scientists, and tends to confuse the public. This is the possibility that global warming, by increasing rainfall and ice-melt at high latitudes, shuts down the Atlantic's circulation, plunging Europe into a new ice age. A current known as the Gulf Stream transports a staggering amount of heat northwards, equivalent to the energy produced by about a million nuclear power stations. Without it, our climate would be between 5 Celsius and 10 Celsius colder - similar to that of Newfoundland. Again, the warning signs are clear: the "subpolar gyre" part of the current has already begun to slow, and through-flow of water between Iceland and the Faroes has declined by 20 per cent over the past 50 years."

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Long but very interesting article!

[xchrom]

1. i didn't know about the hurricane in brazil

that's scary -- i wonder if we'll see another?

[phantom power]

2. meteorologists were calling it "unprecedented"

Of course, nobody bothered reporting the story in the mainstream news. Here in AZ, weathermen spend 90% of their time covering weather in other places, but no mention of this story.

The SCLM strikes again...

[amandabeech]

8. The Weather Channel folks got pretty excited by it, though.

I believe that the Weather Channel has issued a position on global warming stating that it is happening, but fudging on whether and to what extent human activities are responsible. Nonetheless, they are airing a series of specials the week that the climate disaster movie comes out, and have hired an expert in climate change. I think that they also were some sort of technical advisers to the movie as well.

[Salviati]

10. that is one of the most ridiculous talking points that you hear out there.

"but fudging on whether and to what extent human activities are responsible."

That's like saying "Well my house is on fire, but I'm not going to do anything to fight it, because I didn't start it..."

[phantom power]

3. tornadoes in colorado last week

I hear that's pretty unusual too

[phantom power]

4. buffers

>>"The alternative explanation is that the biosphere "sinks", which used to absorb carbon, have suddenly shut down."

That's the damn thing about buffered-systems. A buffer works great right up until it's full, at which point it fails completely. There is no graceful, linear transition.

And we have no idea what the capacity of earth's heat and carbon buffers are, or how close they might be to "full".

That ought to scare the crap out of anybody.

[greenman3610]

5. also, feedback loops

are a consideration.

ie melting permafrost, releases more locked up carbon,
increasing warming...
increased dissolved carbon in ocean raises ocean
acidity, pulling more carbon out of dissolved carbonates
and coral reefs....
alternatively, increased evaporation=increased cloud cover
=more heat reflected out of atmosphere.....

[jpak]

11. All the feedbacks are positive

which is not good news....

[amandabeech]

9. Modern agricultural methods have also decreased the carbon

content of soils. In the olden days, farmers used animal and green fertilizers, as well as fallow seasons and more diverse crop rotations to maintain fertility of soils. In addition to providing NPK, these methods also returned to the soil quite a bit of carbon. Modern methods, however, only add NPK in chemical form and ignore the need for soil carbon. In fact, some proponents of biomass energy want to strip every bit of organic waste remaining on the fields after harvest to make ethanol fuel!

I have not been able to find an internet study or one referenced on the internet quantifying the amount of carbon that could be sequestered if carbon-depleted soils could be revived.

[amazona]

6. if it's already too late then there is nothing to be done

This is what bothers me about the "Mother Nature is doing it" crowd. How is that better? If it is out of our control, nothing effective can be done and we're all doooooomed.

It does no good to plan for such a scenario.

If humans are contributing to it -- and clearly we are -- then there is a chance of saving ourselves by changing our behavior.

To tell people there is no chance is to tell people they might as well not try. If you're on the Titanic, might as well go first class.

[hatrack]

7. I don't see it as an either/or proposition - though some very well might

That's like saying that, in the event that we are all indeed screwed, the logical thing is to go out and buy Ford Excrescenses and Dumber H2s.

With what we've already put into in the atmosphere, warming would continue for another century even if we cut all GHG emissions to zero tomorrow. In that sense, the thing is already beyond our control, if by control you mean rolling things back to 1988, for example.

It is not too late, however to at least ameliorate the worst effects for ourselves and our descendants, and that, along with the very self-interested motivation of trying to head off the very worst potential medium-to-long-term effects, is what this fight is really all about.