Robot Sub Finds Surprisingly Thick Antarctic Sea Ice

[Bill the Cat]

We here at rogue tech are willing to try. You just have to foot the bill for the duct tape and spackling.

billion.jpg

[Jedidiah]

You are making a mistake. You are expecting consistency from shuny.

[rwatts]

A considerable part of the problem is we are a wasteful, indulgent and trashy culture, and we are spreading this disease worldwide.

Some aspects of our materialistic culture are good however. Thus, it will be great when everyone on the planet owns a car, a tele, and has the ability to sit down and watch an episode of Big Brother, all the while feasting up on a couple of Big Macs and a litre of Coke.

Yet as you point out there is a real down side to this, not just for us as individuals but more importantly for the planet as a whole.

How the world managed to work something out re the Ozone Hole seems to be a good lesson here. Sure the hole may have been a natural phenomenon, but all evidence suggests otherwise. And despite warnings of doom and gloom if we did try to do something about it, in the end, countries managed to unite, derive potential solutions and implement them. As a result, there is now some real hope that the hole may be lessening.

Now, if only we could do the same wrt carbon. But the issues at stake are ever so much more complex.

[sylas]

According to a study published in the Proceedings of the National Academy of Sciences, even if we cease and desist all emissions effective immediately, there will be no decrease in temperatures. Our grandchildren's grandchildren will be long dead and still there would be no reversing it.

"People have imagined that if we stopped emitting carbon dioxide that the climate would go back to normal in 100 years or 200 years. What we're showing here is that's not right. It's essentially an irreversible change that will last for more than a thousand years," the lead scientist of the study says.

All perfectly true; but there's a really really important qualifier.

Our future emissions make a huge difference to HOW MUCH and how fast temperatures will rise. I appreciate some people are skeptical of this point; but all I want to do is underline conclusions of the science used by the National Academy, or in projections and models considered in conventional science journals.

According to conventional science, and in particular according to the study quoted by Bill (Irreversible climate change due to carbon dioxide emissions, by Susan Solomon et al in PNAS vol. 106 no. 6, pp 704-709, Feb 10, 2009) it will take at least 1000 years after emissions stop for temperatures to start to fall. This isn't really controversial in the physical science of climate; it's reporting what's already well known to climate modelers. The paper's major contribution is to summarize a number of the long term consequences that will follow from elevated temperature. The paper summarizes effects in three major categories: atmospheric temperature, precipitation, and sea level.

Here's a illustrative figure from the paper:
Solomon2009Fig.jpg

This is a summary of some pretty straightforward physics. The top of the three graphs traces CO2 levels in the atmosphere. There are simplified traces there, which show 2% pa rise in CO2 until a given level is reached, followed by a long slow tail off as emissions stop. The emissions are taken to stop when atmospheric CO2 reaches 450, 550, 650, 750, 850 and 1200 ppm respectively.

The second graph shows temperature, again with six traces for the six scenarios. In each case the temperature rises fairly steeply until emissions stop, and thereafter it falls again, though falling a bit more slowly than the CO2 falls. In each case there is an irreversible commitment to a certain temperature rise (irreversible on the scale of a thousand years). Temperatures will not fall back to pre-industrial levels, except on longer time scales.

The third graph shows sea level rise contribution from thermal expansion (ignoring the contributions of melting ice). This graph also shows six traces, and in this case, sea level continues to rise even past 1000 years into the future. This is actually a pretty straightforward physical consequence of the enormous heat capacity of water, and the long time scales it takes sea levels to equilibriate with temperature.

The conclusions, summarized. The Earth's climate is going to make a significant shift which will not reverse itself when we stop CO2 emissions. The shift has already begun. Emissions still matter, of course, because they determine the level to which temperatures will rise.

That is. The amount of CO2 we emit powerfully influences how far Earth's climate is going to shift. The shift will happen; it is happening; and it will be a "permanent" shift on scales of 1000 years. (But not on scales of a million years, so "permanent" isn't really true.) We can't reverse the change to restore the past. We CAN have a big effect on how much change occurs.

Again, I appreciate that there's public skepticism on these kinds of conclusions, which no doubt I'll continue to discuss from time to time. I'm simply trying to point out an important aspect of what the PNAS paper that Bill cites is saying.

Cheers -- sylas
,

[sylas]

... We are in a long term warming trend,that is on a paleoclimate scale older then possible human influence on climate change. ...

Shunya, I don't think that is actually true. On long scales, (omitting recent anthropogenic factors) we are on a long term COOLING trend. Of course, I'd welcome any clarification or reference to what you mean.

My basic position is that the Holocene Thermal Maximum ended about 5000 years ago, and since then, Earth has been in a very slow decline of temperatures, with some shorter term untrended variations, and with lots of regional variations as well. But overall, on scales of 1000 years or more, Earth shows a slight but pretty definite cooling trend.

Cheers -- sylas

[shunyadragon]

Shunya, I don't think that is actually true. On long scales, (omitting recent anthropogenic factors) we are on a long term COOLING trend. Of course, I'd welcome any clarification or reference to what you mean.

My basic position is that the Holocene Thermal Maximum ended about 5000 years ago, and since then, Earth has been in a very slow decline of temperatures, with some shorter term untrended variations, and with lots of regional variations as well. But overall, on scales of 1000 years or more, Earth shows a slight but pretty definite cooling trend.

Cheers -- sylas

I do not believe the Holocene Thermal Maximum is necessarily THE global maximum before the eventual predicted cooling trend. The parallel drying trend and desertification in recent paleo-climate history has continued through the recent past cooling trend. This drying trend may be likely influenced by human activity as with the warming trend, but I do not believe the degree of influence is clear. I may comment more later.

[Cow Poke]

Climate Change! Everybody talks about it, but nobody does anything about it!

[shunyadragon]

All perfectly true; but there's a really really important qualifier.

Our future emissions make a huge difference to HOW MUCH and how fast temperatures will rise. I appreciate some people are skeptical of this point; but all I want to do is underline conclusions of the science used by the National Academy, or in projections and models considered in conventional science journals.

I believe my skepticism is justified considering the math of population increase worldwide, and the resulting carbon source demands for energy.

[sylas]

I do not believe the Holocene Thermal Maximum is necessarily THE global maximum before the eventual predicted cooling trend. The parallel drying trend and desertification in recent paleo-climate history has continued through the recent past cooling trend. This drying trend may be likely influenced by human activity as with the warming trend, but I do not believe the degree of influence is clear. I may comment more later.

I don't understand your comment, Shunya. The cooling over the last 5000 years since the Holocene thermal maximum is a measurement, not a prediction. An indirect measurement, of course; but a long standing one replicated now by many different sources of proxy information. This is not an "eventual prediction". It's the data indicating that the planet has been in a slow cooling trend over the last 5000 years; it's a measurement of the past.

The data is, of course, open to question in principle, since it is indirect, and based on various proxies for temperature. Are you disputing the very notion of a Holocene Optimum? If there is such a thing, then there is also, by definition, a subsequent temperature decline. But if you don't accept the temperature data that we do have for the Holocene... then on what basis are you claiming that there's a warming trend in the absence of the anthropogenic factors?

And why are we talking about "drying"? I appreciate that precipitation varies as does temperature; but the point at issue was the claim "We are in a long term warming trend ... older then possible human influence on climate change". That's a claim about temperatures. Where does that claim come from? What data is it based on?

Honest questions here. I don't get what you are saying or why. I thought it was just a typo or mixup, but you appear to mean something deeper which which strikes me as somewhat bizarre.

Cheers -- sylas

PS. And on your second post above, in response to my extracts from the paper Bill cited. You said "your skepticism". What skepticism do you mean in this context? The question in that second post was simply nature of the purported "irreversible change"; the point is that human emissions will have an influence on the magnitude of warming, even if there's no prospect of reversing that warming. Isn't that really pretty basic? What's to be skeptical of there?

[shunyadragon]

Climate Change! Everybody talks about it, but nobody does anything about it!

I would not say no one. I have on the drawing board a Perpetual Motion Zero Energy Carbon Dioxide Eater. Looking for investors, Bit coin accepted.

[Cow Poke]

I would not say no one. I have on the drawing board a Perpetual Motion Zero Energy Carbon Dioxide Eater. Looking for investors, Bit coin accepted.

My apologies. I stand corrected. Unfortunately, my finances are committed to the raising and support of bovine methane production units.

[shunyadragon]

My apologies. I stand corrected. Unfortunately, my finances are committed to the raising and support of bovine methane production units.

Then you may be interested in my new and improved non-GMO Tofu cow. No methane production, except by consumers.

[Cow Poke]

Then you may be interested in my new and improved non-GMO Tofu cow. No methane production, except by consumers.

I believe I'll pass.... um.....

I'll pass.

[shunyadragon]

I don't understand your comment, Shunya. The cooling over the last 5000 years since the Holocene thermal maximum is a measurement, not a prediction. An indirect measurement, of course; but a long standing one replicated now by many different sources of proxy information. This is not an "eventual prediction". It's the data indicating that the planet has been in a slow cooling trend over the last 5000 years; it's a measurement of the past.

The data is, of course, open to question in principle, since it is indirect, and based on various proxies for temperature. Are you disputing the very notion of a Holocene Optimum? If there is such a thing, then there is also, by definition, a subsequent temperature decline. But if you don't accept the temperature data that we do have for the Holocene... then on what basis are you claiming that there's a warming trend in the absence of the anthropogenic factors?

And why are we talking about "drying"? I appreciate that precipitation varies as does temperature; but the point at issue was the claim "We are in a long term warming trend ... older then possible human influence on climate change". That's a claim about temperatures. Where does that claim come from? What data is it based on?

Honest questions here. I don't get what you are saying or why. I thought it was just a typo or mixup, but you appear to mean something deeper which which strikes me as somewhat bizarre.

I acknowledge we are at or near the apex of climatic cycle 0ver ~120,000 or more years in time (I have to check the actual length of this cycle) , but I am not willing in to conclude that the Holocene Maximum is the Apex of this cycle. Yes your evidence is indirect. This conclusion as to where we are in this cycle has significance as to how much emissions from human activity cause global warming and desertification. The following data shows we are most likely in the plateau of the apex of the longer paleoclimate cycle without concluding that we are past the apex in a natural cooling trend. I like this data because it is from the Antarctica where long term figures are more stable, and not influenced as much by the over lap of shorter cycles.

I guess I did not totally explain myself. The long term warming trend I am talking about extends back ~18 to 20,000 years ago.

http://www.geocraft.com/WVFossils/last_50k_yrs.html

PS. And on your second post above, in response to my extracts from the paper Bill cited. You said "your skepticism". What skepticism do you mean in this context? The question in that second post was simply nature of the purported "irreversible change"; the point is that human emissions will have an influence on the magnitude of warming, even if there's no prospect of reversing that warming. Isn't that really pretty basic? What's to be skeptical of there?

Ok, this gets merged with all the data and hype that our goal is actually being able to reverse the or even significantly impact the trend of global warming and desertification.

[Jedidiah]

Tofu

No need to talk dirty.