Global Warming

BasketCase wrote:
Actually, we anti-global-warming people don't have to explain why Earth has had hot spikes in the past at all (this is that "past ten thousand years" thing again). Earth has had warm periods--warmer than now--when there were no cars or factories to produce that warming. We don't have to know how those spikes happened; it is sufficient for us to know those spikes CAN happen without people causing them.
I guess it depends on whether you are trying to link cause and effect (as scientists do), or if you are just waving your hands around in the air...
 
Here is a question to all those who have seen the evidence for anthropogenic climate change (carlosmm, gothmog and others).

The mathematician marc kac once said that "a reasonable proof convinces a reasonable man. a rigorous proof convinces an unreasonale man." Subjectively speaking how would you describe the evidence/proof of anthropogenic climate change? Resonable or rigorous?

I think it is reasonable because we have proved correlation pretty rigorously. What we have not proven is causation (because we have not worked out all the details of how and what changes take place for each human activity.

Would you say the same?
 
betazed said:
I think it is reasonable because we have proved correlation pretty rigorously. What we have not proven is causation (because we have not worked out all the details of how and what changes take place for each human activity.

Would you say the same?

I'd say we have gotten beyond the point - in recent years, better modelling software and faster computers have allowed inclusion of many more factors into models. This has resulted in very highly detailed models - and these show that we are able to explain a very large part of the details. All those with major impact are explained, many of those with a weak impact are also explained - we are at the point where we can start using historic data, model ahead from it, check reality - and find things fit! This means that our understanding of causation is close enough to arrive at results with a very small margin of error.

That's (at least borderline) rigorous!
 
carlosMM said:
we are at the point where we can start using historic data, model ahead from it, check reality - and find things fit! This means that our understanding of causation is close enough to arrive at results with a very small margin of error.

Cool! I did not know we can actually do that.

That's (at least borderline) rigorous!

if we can do the above consistently then I am inclined to say that we are better than "borderline" rigorous. We are rigorous.
 
betazed said:
Cool! I did not know we can actually do that.



if we can do the above consistently then I am inclined to say that we are better than "borderline" rigorous. We are rigorous.


as I said: we can start to..... I am waiting for Micheel, A. et al. (in prep) on the influence of the Tibetan Plateau's rise on the monsoon climate..... That guy is doing some very nice stuff :D
 
betazed, this started out as a short post but kept growing and growing :rolleyes:, sorry in advance.

I would say that anthropogenic climate change is a fact.

We have changed the albedo of the earth through agriculture and other modifications of the earth's surface as well as our atmosphere (e.g. cloud properties and soot).

We have changed the opacity of the atmosphere to infrared radiation.

We have changed the way elements are cycled through the earth system (notably nitrogen, but also others - the halogens and the ozone hole for example), which impacts the biosphere and thus secondarily affects various drivers of climate.

These are major forcings that drive climate.

The remaining questions are how the earth system will respond, and will that response be good or bad for continued human development. The answer to these questions is unknown in its details.

For example, it may be that we would be in another ice age right now if not for the impact of humans. I cannot say one way or the other.

We are a long way from being able to say what would have happened in the absence of anthropogenic changes. Just as we are a long way from being able to say what the next thousand years will bring – that may actually be impossible.

We do better on shorter time scales, mostly because we can constrain so many variables with observational data (direct or indirect). This is the process Carlos mentions above.

I once brought up the Gaia hypothesis in this thread, gene90 sort of scoffed. It originates with a brilliant scientist, James Lovelock, as part of a NASA study on how to detect life on mars. Well, one aspect of the Gaia hypothesis goes as follows: atmosphere warms -> ocean warms -> more bugs grow in ocean -> bugs release more DMS into atmosphere -> DMS oxidizes to sulfate -> sulfate aerosol increases albedo thus offsetting warming.

To properly model this feedback we would need a full life cycle model of nearly the entire oceanic web of life. We are nowhere near being able to do that, even without having to incorporate it into a coupled atmospheric/ocean model.

However, we do currently measure sulfate mixing ratios at many places around the globe, and we measure global cloud properties from space.

This example shows the difference between trying to model this feedback, and monitoring whether it is currently taking place or not. We would know if cloud properties altered significantly (as we saw with Mt. Pinatubo). We did not have all this data even 50 years ago, heck 20 years ago.

Similarly for the sun, we can talk about whether the 11 year sunspot cycle is a good indicator of solar output - but we currently have satellites looking at the sun measuring its output. We can observe the receding glaciers and measure its impact on albedo. We can measure the specific contribution of each trace gas to the overall opacity of our atmosphere to infrared radiation.

The reason for action in the face of such uncertainty about the future is described by me in my first post in this thread (#135), and by Carlos in the end of his post #265. Personally I don’t trust Gaia enough to let her run with our anthropogenic changes (as apparently basketcase and gene90 do). I also feel that it is necessary to start creating institutional structures capable of addressing climate change regardless of how the next 50-100 years actually end up.
 
Gothmog, thanks for the detailed reply. don't worry about length. thankfully I do not suffer from ADD and like detail. :)

So here is another thought/question that I would like to throw infront of you all. I agree that in the light of all this data we should do something. But IMHO, environmentalists and scientists must also understand that there is no point in just reiterating that we have got a problem because of which everyone shoudl change their lifestyle. Because nobody is listening. A safe assumption is humans as a group are short-sighted and will not understand something untill it is too late. Kyoto is nice and all but ineffective for that reason. Could scientists/environmentalists suggest something else?

for example, Could we do something active and different? what would it take to actively start removing greenhouse gases from teh atmosphere in an industrial scale or something like that? Maybe we could build giant plants that absorb co2 from the atmosphere?

is that feasible? have some numbers been crunched to see what kind of energy that would take to do that (obviously it shoudl be run on solar or nuclear or hydroelectric or we would burn fossil fuels and create more co2 than we extract)
 
betazed: actually, if the industry would think in mid- to long-term profits, there would be a LOT we can do. But most worry more about the shareholders view of their work - and that is a cheque-based view.

H2 cars COULD BE WORKING and be FINANCIALLY SOUND by now - if the big firms hadn't penny-pinched the research. Just one example.
 
carlosMM said:
betazed: actually, if the industry would think in mid- to long-term profits, there would be a LOT we can do. But most worry more about the shareholders view of their work - and that is a cheque-based view.

That's capitalism for you. It is only concerned about next Fridays stock closing price in the exchange and nothing esle. But we already know that.

Changing that will take a long time, and we shouldn't hold our breath. I think focus should be laid on what can we do which will be acceptable to people like gene90 and basketcase right now. because afterall we are in it together.
 
betazed said:
Changing that will take a long time, and we shouldn't hold our breath. I think focus should be laid on what can we do which will be acceptable to people like gene90 and basketcase right now. because afterall we are in it together.

Not really - someone who doesn't care what his kids will find as 'earth' to live in, or someone who doesn't care that we play 'mesozoic climate' - he's not really in my boat!
 
This is an area of study that I am partially engaged in.

I have just finished a study (with others) of the feasibility of removing CO2 from the atmosphere through chemical means (carbonate slurry, or synthetic polymer). Exactly 'giant plants that absorb CO2 from the atmosphere'. This effort is part of a larger bit of work known as 'carbon sequestration' and sponsored by the DoE.

It is feasible, but will add to the cost of energy (estimates range from 50 - 400%). As the price of energy increases, this becomes a smaller and smaller percent. Some aspects of carbon sequestration are already a reality in Europe due to their emissions trading scheme.

I am also trying to get some money to begin studying other aspects of engineering climate. Initially it would be about putting a small team together with a couple, few years of funding to look at one specific issue. But I have dreams. As I said in another post
I also happen to be interested in the necessity for humans to someday control climate in a systematic way
It seems inevitable to me due to the knowledge we will inevitably gain due to our studies of climate change along with computing advances. And it seems desirable because the last 10000 years have been unusually good for human development and I believe that humans will burn up every bit of hydrocarbon based fuel we can get our hands on.

Part of the problem is the underlying societal attitude that purposely messing with climate is akin to messing with God. The environmental science community is very shy about proposing such things partially due to the potential backlash. I mean there are lots of people who believe that man has never landed on the moon, that the earth is 4000 years old, and that the HARP installation in Alaska is designed to control the weather to nefarious ends. Meanwhile a large number of states are actively engaged in cloud seeding projects without reliable estimates of their efficacy.
 
carlosMM said:
Not really - someone who doesn't care what his kids will find as 'earth' to live in, or someone who doesn't care that we play 'mesozoic climate' - he's not really in my boat!

You mean when sh*t happens because of climate change they will be hit preferentially and you will be spared? ;)

Like it or not, prefer it or not, they are in the same boat as you are. I am not absolving them of their error in ways but just blaming them is not going to get us anywhere. Sure we should keep convincing them and push for their change, but i think we must do more. I am just not sure if there is any such thing that we can do which is the reason I am asking. { remember today is thursday and I am pessimistic. :) }
 
betazed said:
I think focus should be laid on what can we do which will be acceptable to people like gene90 and basketcase right now. because afterall we are in it together.
That’s what Kyoto was intended to be. It is a totally unambiguous treaty that is way too modest to solve the problem. It is so incredibly weak that it is almost a joke. Apparently not everybody think it is a funny joke though.

I think GW deniers only will accept actions that make sense economically. It is however lots of things that can be done to reduce pollution that will give financial benefits that could justify the investments. For example there are many cases where converting to a different energy source could give many benefits. The problem is that nobody will convert before the infrastructure is in place, and of course nobody will build the infrastructure before there is a marked for it. In many cases no private companies are willing to take the risk in starting this process, so nothing is done. But this kind of problems should be easy to solve with an active government involvement, and it will be profitable for the society as a whole. This kind of government intervention could may be a good place to start?

Gothmog said:
I mean there are lots of people who believe that (…) the earth is 4000 years old
No, you must have confused the numbers. The world stated in 4000 BC. That makes it 6000 year old. Haven’t you played civ? Apparently the bible estimates the age of the earth to be about 6000 years too. Coincident? I don't think so!:p
 
Gothmog said:
BasketCase wrote: I guess it depends on whether you are trying to link cause and effect (as scientists do), or if you are just waving your hands around in the air...
Scientists are trying to do that right now. They're failing. A while back in this thread, I asked a few questions along the lines of how much energy CO2 absorbs, and how much that energy would warm the planet. Nobody posted so much as ONE link answering those questions, therefore the answer is not to be found anywhere on the web. Which means nobody actually knows how much warming X amount of CO2 would cause.
 
I thought Gothmog answered it shortly after you asked :confused:.

…

Yes he did: :)
Gothmog said:
I did not grab stats off a random web site, I was summarizing current knowledge in the climate community.

I already stated that the additional energy trapped is about 1%. If all other factors remained equal the warming from a 100 ppm increase in CO2 is about 0.25 degrees. That is how much would be expressed as heat. The energy absorbed is tough to answer because we are talking about a dynamic equilibrium (as I described in an earlier post).
If you need his source you could try to ask for it, I guess.
 
betazed said:
That's capitalism for you. It is only concerned about next Fridays stock closing price in the exchange and nothing esle. But we already know that.

Changing that will take a long time, and we shouldn't hold our breath. I think focus should be laid on what can we do which will be acceptable to people like gene90 and basketcase right now. because afterall we are in it together.


I'm scaling back participation at the moment, but comments like the above annoy me so I'm going to make a preliminary response right now.

Apparently some people think "money" is a dirty word. "Money", however, is just a proxy for resources, labor, and time. Have you ever looked up how many tons of concrete, glass, and steel you need to build a solar power plant, vs how many for a coal plant? (Hint: solar plants consume more non-renewable resources to build than nuclear plants of the same capacity, not including the additional infrastructure necessary to store power for use at night and on cloudy days.) Since it's very un-PC for me to express it in money, maybe I should try to express the cost of "alternative" energy sources in terms of the additional thousands of tons of glass, steel, and concrete that they will require? Maybe I should express it in hundreds of acres of forests that will be leveled to stripmine out the metals and aggregates to build solar arrays? Maybe I should express it in terms of lives lost in industrial accidents to get those resources? Maybe I should express it in millions of square miles of environment caked over with gallium-arsenide solar panels? Or in terms of groundwater contaminated from arsenic mining and processing? Or the number of birds chopped up in wind turbines? Or in the losses to our industrial base when we deliberately turn over power production to energy sources that are subjected to variability of climate? GothMog has said that climate is going to get bumpy with our without our modification of it, now which is going to be more affected by those "bumps", coal or solar?

Modern coal power is "greener" than solar in every category but CO2 emission.
 
gene90 said:
Apparently some people think "money" is a dirty word. "Money", however, is just a proxy for resources, labor, and time. Have you ever looked up how many tons of concrete, glass, and steel you need to build a solar power plant, vs how many for a coal plant? Since it's very un-PC for me to express it in money, maybe I should try to express the cost of "alternative" energy sources in terms of the additional thousands of tons of glass, steel, and concrete that they will require? Maybe I should express it in hundreds of acres of forests that will be leveled to stripmine out the metals and aggregates to build solar arrays? Maybe I should express it in terms of lives lost in industrial accidents to get those resources? Maybe I should express it in millions of square miles of environment caked over with gallium-arsenide solar panels? Or in terms of groundwater contaminated from arsenic mining and processing? Or the number of birds chopped up in wind turbines? Or in the losses to our industrial base when we deliberately turn over power production to energy sources that are subjected to variability of climate? GothMog has said that climate is going to get bumpy with our without our modification of it, now which is going to be more affected by those "bumps", coal or solar?

Maybe you can do all that, but it still would not tell me what you are trying to say.

Maybe you can not say all that and say what you are trying to say clearly, because I am still clueless. And where the hell did you get the idea that "apparently" I or other people think money is a dirty word?
 
betazed said:
Maybe you can do all that, but it still would not tell me what you are trying to say.

Maybe you can not say all that and say what you are trying to say clearly, because I am still clueless.


?????

And where the hell did you get the idea that "apparently" I or other people think money is a dirty word?

Your comment on "capitalism", and another's comment about "people with bucks on their brains".

A move to "alternative" energy would be irresponsible socially, economically, and environmentally. If CO2 is the only reason for the shift, I'll stick with fossil, thank you.
 
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