It's all over but for the sweating?

[Arragonis]

How about finding the something else first, before we run to the hills and hide ?

How much of the warming since the last ice-age should be attributed to CO2?

Since this is a science blog after all, I thought it would be appropriate to end this post with more solid science in it.

Overall, there was a 3.5°C degree increase taking place concurrently to a CO2 increase from 180 to 280 ppm. If the warming is entirely due to CO2, then the climate sensitivity should be ΔTx2 ~ 3.5°C/log2(280/180), or about 5.5°C per CO2 doubling. But as I explained above, this conclusions is not supported at all by the above correlation. However, it does imply that if anyone is calculating a probability distribution function for the temperature sensitivity to CO2, then they should cut it at 5.5°C, because it simply cannot be any larger than that.

On the other hand, my best estimate for the climate sensitivity, is that CO2 doubling should cause a 1 to 1.5°C temperature increase, or about 0.65 to 1°C for a 180 to 280 increase in the CO2. In other words, at most a quarter of the observed 3.5°C should have been caused by the CO2 feedback. The rest is something else.

[TheEnemy]

Originally Posted by NeilBlanchard

I have no blessed idea - the sooner the better - or the sooner the less terrible for us and the rest of life on the planet.

There is a lot of "momentum" in this; through feedback/amplifying effects, etc. If we completely stop all carbon output right now, we'd get another 0.5-1C rise (on top of the ~0.8C we have already had).

We probably have 5-8 years to turn things around - 10 years on the outside, if we want to avoid 3-4C rise; let alone 2-3C. If we go another 20-30 years without major carbon cuts, then we'll likely see 4-5C. If we hit ~6C then we get hydrogen sulphide; a deadly poisonous gas, coming out of the ocean. Go here to read about what sorts of things happen at increasing temperatures.

If we speed past 450ppm, then all bets are off.

First off, we are most likely going to exceed 450, at our current rate of increase we have 25-30 years before we hit that point.

Second where are you getting that we have increase temperatures by 0.8C?

Third, the whole globe will not warm the same ammount. Like I said before, the colder regions will see the most warming so placing that 6C average warming to the hotter regions and then showing what bad things will happen at that temperature isn't accurate.

Arragonis: I am humoring James who thinks that the sun has had no effect on current global warming. Of course by picking my start and end points I can choose whatever warming ammount I want for projections, though I think the 1958-2005 values should give a somewhat accurate corrections to be able to predict off of.

[TheEnemy]

James believes we will all die (400-2000ppm at 2ppm/year = 800years 500 if you expect the rate to increase)
Neil thinks we might all die
Me, I belieive we are living (or soon to be) that Chinese curse... we are in for some interesting times

[user removed]

The doomsday predictions continue. Atmoshperic oxygen levels were once 35% or 350,000 parts per million. They have dropped to just under 21% in catastrpohic events and historical time periods. Lower oxygen levels were the principle reason for human evolution.

"It's all over but the sweating."

Yep the sky is falling once again. CO2 being the basis for plant growth would lead any rational person to say, grow more plants.

As mankind evolves and researches the possible solutions, we may find the extra airborne CO2 becomes a "fuel tank" for solar atmospheric reprocessing into future fuels. Basically the carbon we have released by drilling for oil gets used over and over again in the future for power production. I would not be surprised in the least if that process did not preceede the practical electric car battery, which has been predicted for decades.

High intensity artifical photosynthesis to create infinitely renewable fuels using sunlight an the available supply of CO2.

regards
Mech

[user removed]

Originally Posted by TheEnemy

James believes we will all die (400-2000ppm at 2ppm/year = 800years 500 if you expect the rate to increase)
Neil thinks we might all die
Me, I belieive we are living (or soon to be) that Chinese curse... we are in for some interesting times

And how many people 800 years ago predicted the conditon of mankind today with any real precision.

regards
Mech

[NeilBlanchard]

Of course the sun has something to do with warming the earth. But the changes in the sun's output are not enough to explain the increase in temperature. Carbon dioxide slows the rate of heat loss back into space, and the increase in carbon dioxide is the only way to explain the temperature increase.

I may be mistaken, but the 0.8C is the current increase we have already seen. Look it up.

Global Surface Temperature Trends | Center for Climate and Energy Solutions
Climate Change: Key Indicators

We were not alive in all those past conditions - and we would not want to have been. We are alive here and now, along with all the other life forms that have adapted to the nearly steady state of 170-270ppm carbon dioxide, for ~650,000 years.

And of course the arctic has greater than average temperature rise - what else is causing the ice to melt so fast? Physics dictates that if you slow down the heat loss by adding more "insulation" in the form of carbon dioxide - things will get warmer.

It's not doomsday stuff - it is reality. We know it because we see it. The data shows us reality, and we can compare it to the past events. We know we will be in a heap of trouble if we continue like we are.

[jamesqf]

Originally Posted by Arragonis

How about finding the something else first, before we run to the hills and hide ?

We already do know what the "something else" is: those Milankovitch cycles - Wikipedia, the free encyclopedia that you should be familiar with if you bother to learn anything at all about climate.

[jamesqf]

Originally Posted by Old Mechanic

The doomsday predictions continue. Atmoshperic oxygen levels were once 35% or 350,000 parts per million. They have dropped to just under 21% in catastrpohic events and historical time periods. Lower oxygen levels were the principle reason for human evolution.

Bull. Yes, the Earth's atmosphere once - about 300 million years ago - had higher oxygen levels just as it once was composed of methane &c with no oxygen: Geological history of oxygen - Wikipedia, the free encyclopedia Give life a few hundred million years to evolve, and it will handle such things just fine.

If you have a time machine and could skip ahead a hundred million years or so, it's pretty likely that you'd find the planet once again filled with life, the evolved descendants of what few creatures manage to survive the Anthropocene extinction event. Just as we are the evolved descendants of the few that survived the Permian-Triassic extinction.

CO2 being the basis for plant growth would lead any rational person to say, grow more plants.

Sorry, but your "rational person" obviously doesn't know much about plant growth. CO2 is not the basis for plant growth, any more than oxygen is the basis for animal growth. Increasing CO2 does not (in general) increase plant growth, which is limited by factors like sunlight, temperature, water, and minerals.

The lower prehistoric CO2 levels were more than sufficient for plant growth - obviously, since there were plants in profusion. Nor do we find that plants are growing faster than they were a century ago because of the increases in CO2.

[radioranger]

The sun is the other factor i dont hear talked about , if it burps once, we're all toast anyway. personally for me until they do the free and cheap stuff first and stop trying to control everything, I dont believe them a bit.

[TheEnemy]

Originally Posted by NeilBlanchard

Of course the sun has something to do with warming the earth. But the changes in the sun's output are not enough to explain the increase in temperature. Carbon dioxide slows the rate of heat loss back into space, and the increase in carbon dioxide is the only way to explain the temperature increase.

I may be mistaken, but the 0.8C is the current increase we have already seen. Look it up.

Global Surface Temperature Trends | Center for Climate and Energy Solutions
Climate Change: Key Indicators

We were not alive in all those past conditions - and we would not want to have been. We are alive here and now, along with all the other life forms that have adapted to the nearly steady state of 170-270ppm carbon dioxide, for ~650,000 years.

And of course the arctic has greater than average temperature rise - what else is causing the ice to melt so fast? Physics dictates that if you slow down the heat loss by adding more "insulation" in the form of carbon dioxide - things will get warmer.

It's not doomsday stuff - it is reality. We know it because we see it. The data shows us reality, and we can compare it to the past events. We know we will be in a heap of trouble if we continue like we are.

Ok so your taking the temperature change from 1880 to present, unfortunately there is also a definite change in solar output between now and then that has to be accounted for, when I used 1958 it was as far back as I could go and still maybe not have to account for solar output.