Actually, as I understand it major and essentially permanent climate change could happen over a period of a few years, as I understand it. Once matters reach a tipping point, the climate could rapidly move into its new stable state.
As I recall, that desertification is believed to be originally of human origin as well; due to ancient overgrazing not global warming though. Once created, a desert tends to be pretty stable or even spread.
Why would co2 based damage be non-reversible? It’s not like ozone killing freon which floats up beyond our reach.
Beyond that, I’ve been advocating the use of technology to directly affect temperature and Obama has issued statements to that effect. I think it’s retarded to spend trillions of dollars re-inventing the wheel when the solution should be focused directly on the problem. The current political climate is to spend money reducing Co2 while China and India erase any gains with their increases in Co2. Will get boned twice by these 2 emerging nations. We’ll spend more and get less while becoming more dependent on their cheap Co2 flinging labor.
The lack of rainfall has rather more to do with it.
If I’m not wrong there has been a lot of success with “reclaiming” desert into productive land by planting trees around the edges - which then expands and reclaims at least forestry that becomes self sustaining (i.e doesn’t need to be constantly irrigated)
And my understanding also was that much of the increase in desert size was caused by man - over grazing, clear felling, poor rotation of crops etc etc
Because the new climate will involve all sorts of changes. The release of methane from underground reservoirs, changed ocean currents and jet stream, increased heat absorption due to the lack of glaciers or ice caps, etc. Climates tend to be stable for long periods; once Earth’s climate shifts, that will be the new norm. Just as it took us a huge effort to shift the climate one way, it would take another huge effort to push it the other, if we could at all. Reducing CO2 at that point won’t stuff methane back underground or reform the glaciers.
The genocide in Darfur is caused by people deciding to kill other people. Desertification may make it easier for them to justify to themselves, but it doesn’t actually take over people’s minds like a telepathic alien and make them kill.
The conflict seems be stratified into nomadic peoples against settled tillers of the land, which is a pretty old human story, exacerbated by religious, tribal, and ethnic differences. Certainly desertification can spur such a conflict, but desertification in other areas has not – genocide remains a human choice, although sometimes a product of mob psychology instead of conscious planning.
I see no evidence that human beings have ever collectively changed their behavior for the good of the species, the planet, or anything else.
You have nothing to base that on. Stop listening to Al “private jet” Gore. Co2 could be scrubbed on a large scale if need be. If it’s taken out of the atmosphere then it’s effects go with it. It’s not something that would take a long time to do. Obama’s science adviser is already talking about it publicly.
And if you’re referring to methane at the bottom of the ocean then you need to show that the water temperature would increase at that depth and also the changes in water pressure from additional water from melting ice caps.
You’re saying that there won’t be any additional methane released? Or that the lack of polar ice caps won’t contribute to warming beyond that caused by CO2?
And your crack about Al Gore tell us a lot about how you arrived at your opinions on this issue. After all, Der Trihs is not Al Gore and doesn’t use a private jet, but if he shares the concerns about a GW tipping point, he is therefore linked to Al Gore, and therefore to Al Gore’s private jet, and therefore has no credibility on this issue.
If the ocean level rises then it adds pressure to the trapped methane and cooler water to the mix.
Al Gore is the poster child of doom and he’s scaring people. We are not in a dire situation and if by some chance Co2 becomes a real problem then it can be removed as needed.
I’m quite pessimistic about about global warming and concerned about all of the various impacts, but I find this scenario highly unlikely.
On a different note, relying on carbon scrubbing is like relying on cold fusion or antimatter drives. It’s foolish to rely on technologies that are always just around the corner when we could instead just reduce pollution today. Further, as already mentioned, carbon dioxide is not the only greenhouse gas that we’re releasing in unsafe quantities; there’s also methane. Besides that released directly by human activity, there’s a great deal trapped in arctic bogs. Billions of acres in the arctic was formerly permafrost, meaning permanently frozen. Due to global warming it is rapidly become tempafrost. Whenever a frozen bog melts, methane is released into the atmosphere.
Yeah, I’m pretty sure we’ll make a difference. The important question to me is, which difference will we make? And to that, I get to give my favorite answer to everything: It depends.
The three questions we really need to answer regarding climate change are:
[ul]What will be the eventual concentration of CO[sub]2[/sub]* in the atmosphere?[/ul]
[ul]What will the temperature change be from that greenhouse gas (GHG) concentration?[/ul]
[ul]What are the effects of such a temperature change?[/ul]
*I’m going to say CO[sub]2[/sub], but significant effects from other greenhouse gases such as methane, nitrous oxide, and tetrafluoromethane exist. Those will also have to be dealt with.
For the first question, what will be the eventual concentration of CO[sub]2[/sub] in the atmosphere? We get to choose the answer, more or less. If we could power the world with a thought, we could stop it at its present 380 ppm, but we can’t do that.
Let’s say we take CO[sub]2[/sub] concentrations up to 550 ppm by 2100 (level 2 scenario from the US Climate Change Science Program.) With that concentration, there would be a ~70% chance of temperatures reaching 2-3°C higher global average than without human GHGs and ~10% chance of 3-4°C (cite.)
Or we could say we take CO[sub]2[/sub] concentrations as high as anyone (including, to my mind, inactivists) could want – somewhere around 700-900 ppm. Then there would a ~1% chance of temperatures reaching 2-3°C higher than preindustrial global averages without GHGs, and a ~12% chance of 3-4°C higher, and ~78% chance of >4°C higher (cite.)
At the 2-3°C change level we have:
[ul]Droughts that expose 0.4 to 1.7 billion people to water scarcity.[/ul]
[ul]An additional 3 million people at risk of flooding.[/ul]
[ul]An increase in the agricultural productivity in wealthy nations such as Canada and Russia, and a decrease in agricultural productivity in poor tropical nations such as Congo (both of ‘em,) India, and Peru.[/ul]
[ul]Bleaching a majority of the world’s coral reefs with negative consequences for communities that rely on them for fishing and tourism.[/ul]
[ul]Rapid increase in frequency and breadth of heat waves with attendant crop failures and forest fires.[/ul]
[ul]Widespread deglaciation of the ice sheets on Greenland and the West Antarctic.[/ul]
[ul]High risk of extinction for 20-30% of the planet’s species.[/ul]
At the 3-4°C change level we have:
[ul]High probability of total melting of Greenland’s and West Antarctica’s ice sheets.[/ul]
[ul]Falling global food production – no longer to wealthy northern nations enjoy and increase.[/ul]
[ul]Tens of millions more exposed to increased flooding risk.[/ul]
[ul]Hundreds of millions to a billon more exposed to increased water scarcity.[/ul]
[ul]Ecosystems on land may completely switch from soaking up atmospheric carbon to a net balance of adding carbon to the atmosphere.[/ul]
[ul]Widespread complete elimination of coral reefs.[/ul]
(From Hot Topic by Walker and King, but similar information can be found in the IPCC’s 4th Assessment Report, WGII, chapters 19 & 20, especially tables 19.1 and 20.4.)
The higher the temperature gets, the worse the potential consequences, and eventually too many people will be affected to ignore. That will determine the political climate future generations operate in. For now, I hope we have enough political will to avoid the worst of the consequences. My WAG is that given political limitations we can stabilize CO[sub]2[/sub] around 500-550 ppm, but I don’t really have any way of knowing.
I work in the coal power business in Canada and I can tell you that there is no company in this country that sees ANY future in coal power as it currently exists.
The writing is on the wall. All developed nations will be reducing CO2 emissions over the coming decades. No company with half a brain will be investing in industries with no plan to reduce emissions.
There is currently no business reason for this change. Coal plants are supplying fat profits, but it’s clear the cost of carbon emissions will be too high over a twenty-year timespan to keep them profitable.
All this due to public/political pressure. And we (apparently) only at the very front of the impacts of climate change. Imagine the political pressure to make further reductions once significant impacts occur. And as the developed countries continue to develop, pressure will build on them to change.
I am certain that the climate is changing, but I am equally certain that humans will deal with the change and cut CO2 emissions dramitically over the next 20-30 years. I don’t foresee massive impacts to our lives.