THE Earth in 2100 Thread (merged)

[Heineken]

Oh, and all of the fossil and sediment record shows the world was a very nice place to live when it was 6C warmer. Much less desert. Much more forest and grasslands.

When it was 6oC warmer there were no people. No human impacts. The world was pristine. Maybe it was nicer for reptiles and bugs, but how about for our complex civilization?

It won't be a nice place for crops, especially the grains on which our civilization is utterly dependent. They don't photosynthesize well at higher temperatures and will die. Maybe we can shift some of that agriculture farther north, but it will almost certainly be a case of too little too late.

Billions will starve.

Similarly, forests have ALREADY been deteriorating as temperatures have risen. Bugs, plant diseases, pressure from violent storms and fires.

When temperate forests disappear suddenly the soils degrade rapidly. They won't be replaced by lush jungles. More likely by thin grasses and sagebrush.

Doesn't bode well.

I find the argument that basically says, Well, we can't predict the future, so therefore we shouldn't worry about global warming, to be rather specious.

[dohboi]

Not only are we headed to global temperatures not seen in millions of years, we are headed there very quickly.

And rate of change is everything.

If someone gently brings a cannon ball toward you, it is very easy to "adapt" by moving aside.

If someone sets of a cannon right at your head, point blank, adaptation is not an option.

The only difference is rate of change.

We are in the second scenario.

Few complex life forms will survive the blow.

[kiwichick]

will the arctic methane release be factored into the next IPCC report?

[Pretorian]

No worries, kiddos. Gaia will bounce back eventually. 10, 15 million years from now it will be just like it was, may be even better, and more importantly, human-free. Death is the destination of every life form, so, there is no point in fussing really. Shame we have to check out so early , perhaps, if we could last half or even a third of what a normal species live, like another million years or so, we could have reached the stars or even learn not to soil our own home. I doubt about the latter though.

[dohboi]

Pret, no one can predict the future perfectly.

We were already well into a mass extinction event before the effects of GW really got going. So now with GW we are in something like a double extinction event. Does that double the recovery time? Does it increase it by an order of magnitude or more? If the latter--hundreds of millions of years rather than tens--we are then pushing up against the time that the sun will be to big and bright for the planet to support life, so recovery would not be possible. And of course any number of other terrestrial or non- events could set back the recovery in the intervening period.

Life on the planet may recover as you predict, but there is just no way to know that for certain.

[AgentR11]

Does that double the recovery time?

Like most things in nature, its more an ex & log exercise, not a straight multiple. The tails of those look largely the same regardless of what linear factor you apply to them. So you can basically expect that as the number of species remaining drops, the ratio of possible survival nitches to number of species improves, thus lowering the pressure of the extinction event as it proceeds. Once the event is over, you have a long period where very few species are producing a huge amount of biomass, and from their differentiation proceeds over time.

We're currently on the part of the curve where the linear factors are noticeable, but don't give them more potency than they rate.

One should also remember, that the climate phase the Earth is headed towards is nothing unprecedented, its spent millions of years in just such hot-phases, with tons of life romping around enjoying the climate. (none of the rompers being primates might however, give one pause, I doubt Gaea gives a flip, but this writer might).

[Lore]

One should also remember, that the climate phase the Earth is headed towards is nothing unprecedented, its spent millions of years in just such hot-phases, with tons of life romping around enjoying the climate. (none of the rompers being primates might however, give one pause, I doubt Gaea gives a flip, but this writer might).

Those former beasties had hundreds of thousands of years to adapt to changing climate. When history showed relatively quick distortions in climate, life met sudden death.

[AgentR11]

Correct, a 95% diversity loss wouldn't be at all surprising. My point is about that remaining small percentage, once you're in that small percentage band, there are so many vacated hiding spots/niches that the chance of a match between the remaining species and the available niches rises. They only have to "weather the storm" as it were.

This means a huge loss in biodiversity, just as in past extinction events; but the few that remain end up with a whole planet to fill and exploit.

Don't forget, that in these extinction events, adaptation isn't so much species A remaining species A but better suited; but rather species #1-100,000 going extinct, specie #100,001 tolerates and survives, and then begins adaption and evolving into #100,002+ as life goes from tolerate&survive to thrive&exploit.

That's why the speed argument always seems so weak to me; if the magnitude is slow enough to permit simple changes in range for survival; its not abrupt. Once it is abrupt, there is no simple adaptation possible. The only difference this time around is the presence of conscious primates who can observe and acknowledge the extinction event that they are creating.

[GASMON]

Sooner boil than freeze !! - At least my bloody heating bills will disappear !!!!!

Yes it's a bag of shit - but at least the sodding bankers will cop it as well !!!

Gas

[dohboi]

Warmer climates have tended to spur faster speciation in the past--something about the warmth causing bodies to get smaller since smaller bodies shed heat more easily, but smaller bodies can adapt to smaller habitats...

On the other hand (and to save my reputation as an uber-doomer '-), all this assumes that we don't get into Hansen's Venus Syndrome. He seems to think this is pretty much a sure thing if we burn all the carbon there is to burn, and we seem to be heading in that direction. And he knows a bit about Venus, having done a lot of the groundbreaking work on the climate of that planet.

Keep in mind that it is not really about individual species finding the right niches, but of communities of species that can coexist and foster each others' existence finding the same niche at the same time. No individual life form can live by itself.

[AgentR11]

No individual life form can live by itself.

Algae sure can.
Cyanobacteria can.

[AgentR11]

Hansen's Venus Syndrome.

I think Hansen's going *WAY* out on a limb trying to predict that far out.

Its not unreasonable to think we could push the climate out of its current cold-phase equilibrium over into the Earth's normal hot-phase equilibrium; but its quite a reach to think we even know enough about that side's equilibrium state to predict pushing out of that, into an unknown, unbounded climate state.

He seems to think this is pretty much a sure thing if we burn all the carbon there is to burn,

There is no *if*. Only *when*.

[Serial_Worrier]

A several degree rise will open up a billion acres of farmland in Canada & Russia. Good times ahead!

[AdTheNad]

A several degree rise will open up a billion acres of farmland in Canada & Russia. Good times ahead!

The higher the sea rises the more land we have! Wait that doesn't sound right. Well at least there will be good farm land in Russia to replace the stuff that burns and gets flooded there.

[kiwichick]

if the worst case plays out we will lose most of the best land

and most of russia and canada have had the best land scrapped off by the ice sheets

[clif]

Not to mention, the need to build completely new infrastructure to support farming at latitudes which previously hasn't been able to be farmed do to the climate pre climate change.

BTW this new construction will have to be achieved in a declining energy environment.

[dohboi]

Not to mention that the growing season in northern Canada and Siberia lasts about two weeks.

[kiwichick]

dohboi

tut,tut

it could be 4 or 5 weeks by 2030

[dohboi]

Nice point. The amount of sun shine and its low angle won't change, though; GW doesn't change the tilt of the planet.

[Lore]

A several degree rise will open up a billion acres of farmland in Canada & Russia. Good times ahead!

The higher the sea rises the more land we have! Wait that doesn't sound right. Well at least there will be good farm land in Russia to replace the stuff that burns and gets flooded there.

You can't farm the tundra productively, no matter how pleasant the temperature may get there.