Global Warming

[ivor]

Here's an interesting side of the Global Warming debate.  It's a seventy-three minute video.  Some of the politics I disagree with.  The science of it was very interesting.

[Sibling Zono (anon1mat0)]

On the solar activity argument, the danish guy that has been working on it doesn't say that is one thing or the other but that the effect (of solar activity, cosmic rays and stratospheric clouds) should be included in the simulations. Although he claims that he has been pressured because of his opinion. OTOH, there is a very comprehensive article in the printed edition of Scientific American for anthropogenic global warming (the header of the article can be found here). The printed article says that it was considered.

The subject is a difficult one but there is a political agenda on both sides (although I would think that there are more economic interests on the 'everything is fine' side).

[ivor]

I've always been pro-global warming.  Is it true what they are saying about CO₂ lagging temperature by 800 years? 

[beagle]

Haven't checked out the video yet  but I've seen interesting stuff by Bjorn_Lomborg elsewhere.

Anything that has The Economist and Scientific American lining up on opposite sides is interesting IMHO, in that they're both intensely rational publications. Whatever the science I suspect that as The Economist implies, big science and environmental interests are going for the player rather than the ball.

As I understand it, one of the arguments is that spending money now on development is better than using it to fight global warming, in that developing economies are messy economies (and always have been).

On the opposite side of the argument is the car boom in China and India, and the possibility of mass starvation if (big if) climate change is already moving the monsoon time and latitude.

[Griffin NoName]

Unless we evolve to eat cars

Seems always to be an assumption that there is some point in "fighting" global warming. I suppose if at best we can delay it, or prolong it, we might preserve human life long enough to colonise space successfully. May be time to ask for an International Referendum on quantity over quality of life now.

[ivor]

If CO₂ lags temperature by 800 years then it seems the simple answer is CO₂ has nothing to do with global warming.   They point out in the video that water vapor is a much larger green house gas than CO₂.  That sounds reasonable to me.

Where did they get that graph on solar activity?

[Aggie]

If CO₂ lags temperature by 800 years then it seems the simple answer is CO₂ has nothing to do with global warming.   They point out in the video that water vapor is a much larger green house gas than CO₂.  That sounds reasonable to me.

Where did they get that graph on solar activity?

Water is a much more important GHG than CO₂ (in terms of spectral absorption)  - but it's also in physical equilibrium with surface water & ice, so it's a bit of a straw man. 

Actually, methane is 4x as powerful a GHG as CO₂, so there are arguments to be made for exploiting any resources which have the potential to be released (clathrates etc.).  Rotting vegetation flooded out by any new hydroelectric dam can release the GG gas equivalent of a fossil-fueled power station for the first 10 years or so of it's life - mind you, it's in-cycle carbon rather than 'old' sequestered carbon.

[ivor]

One volcanic eruption trumps all those right?  We don't see spikes in temperature because of those.

I am still interested in seeing that solar activity chart and comparing with a temperature chart.

Water is a much more important GHG than CO2 (in terms of spectral absorption)  - but it's also in physical equilibrium with surface water & ice, so it's a bit of a straw man.

Could you explain what that means in terms any idiot can understand? 

[Swatopluk]

If it gets warmer, more water evaporates, ice melts and exposes a dark surface that absorbs 90% radiation instead of reflecting 90%.
Water vapor absorbs radiation in a different part of the spectrum than CO₂. That certain substances act as GHGs and with different intensity is due to different absorption efficiency and their position in the spectrum. Potent greenhouse gases fill gaps that radiation usually escapes through. It is like blocking the safety valve of a steam boiler. Adding extra stuff where other substances already absorb makes a much smaller difference, as is the simple increase in concentration outside those gaps.
Volcanoes also emit aerosols that compensate partially for the increased CO₂ (cloud-cooling). There have been volcanic events in world history that had a tremendous effect on climate (e.g. the Dekkan volcanism).
That there is no simple connection T = f(c(CO₂)) is due to the nonlinearity of many coupled effects (positive and negative feedbacks).
A simple example that seems paradox is the behaviour of a continuous chemical reactor with external cooling. Under certain conditions the reactor will become unstable, overheat and explode, when the temperature of the cooling medium is lowered. If one looks at the balance equations it becomes clear, why but a layperson would usually not believe it without demonstration (the lab demonstration in the practical course is quite impressive).
---
I thought methane was 20 times as effective as carbon dioxide, must check

[Aggie]

One volcanic eruption trumps all those right?  We don't see spikes in temperature because of those.

This is the thing - anthropogenic sources are relatively minor, but what is the effect in the long run?  Example:  A pack-a-day cigarette habit is a relatively minor cost compared to the sum total of housing, food, vehicle expenses etc, but if continued over a lifetime (and if the price of smokes keeps outpacing inflation, like it is up here), could have significant effect compared to if that money was instead rolled into a compounding interest investment.  I.E - even though the 'natural' amount is huge, adding consistently to that over time could make a measurable difference.

Water is a much more important GHG than CO2 (in terms of spectral absorption)  - but it's also in physical equilibrium with surface water & ice, so it's a bit of a straw man.

Could you explain what that means in terms any idiot can understand? 

OK - if we didn't have ANY greenhouse gases (GHG), this planet would be too damned cold. 
The  water in the atmosphere is the most important GHG and absorbs much more radiation than CO2 does, but it is continuously falling out as rain and evaporating back up, so there's little chance of increasing the net distribution of water (can be argued that more will evaporate as the temperature rises, but more clouds may help to reflect more incoming solar radiation, slowing down the warming process.  Water is a bit of a wild card).


IMO, all the political effort currently being put into this global warming debate should be put into making our energy use more efficient and environmentally friendly - there are many MANY other air pollution issues caused by the combustion of fossil fuels that are having measurable impacts on human health (especially in cities); also, if we can slow down fossil fuel consumption rates we'll be able to use this resource for longer.

Do agree a bit with the idea of putting effort into PROPERLY developing technologies in developing nations so that they grow up cleaner than the last generation - it's easier to build something right the first time as these are needed than to decommission an old nasty pollution-generator and rebuild an clean one as a replacement.

[Aggie]

I thought methane was 20 times as effective as carbon dioxide, must check

I may be wrong...  that was off the top of my head.  4x is either water or methane, I think, but methane has a half-life in the (oxygenated) atmosphere, so that may account for the lower number if it's a cradle-to-grave factor (i.e. it becomes CO2 eventually and loses the absorption advantage).

[ivor]

I totally agree on less pollution, more energy efficiency thing.  Our energy security is important.

The new R134A freon used in air conditioning is a terrible green house gas.

Does any body know where to get that solar activity graph?

[Sibling Zono (anon1mat0)]

There are a bunch in the wikipedia entry for Solar variation.

A 2006 study and review of existing literature, published in Nature, determined that there has been no net increase in solar brightness since the mid 1970s, and that changes in solar output within the past 400 years are unlikely to have played a major part in global warming. It should be stressed, the same report cautions that "Apart from solar brightness, more subtle influences on climate from cosmic rays or the Sun's ultraviolet radiation cannot be excluded, say the authors. However, these influences cannot be confirmed, they add, because physical models for such effects are still too poorly developed."

The danish guy I was talking about is Henrik Svensmark. Here is a link of the interview on Discover Magazine regarding global warming, solar activity and cosmic rays. Interestingly, the wiki's page on him mentions a study that challenges that theory.

Muddy waters...

[ivor]

Great article!

The basic idea is that solar activity can turn the cloudiness up and down, which has an effect on the warming or cooling of Earth's surface temperature. The key agents in this are cosmic rays, which are energetic particles coming from the interstellar media—they come from remnants of supernova explosions mainly. These energetic particles have to enter into what we call the heliosphere, which is the large volume of space that is dominated by our sun, through the solar wind, which is a plasma of electrons, atomic nuclei, and associated magnetic fields that are streaming nonstop from the sun. Cosmic-ray particles have to penetrate the sun's magnetic field. And if the sun and the solar wind are very active—as they are right now—they will not allow so many cosmic rays to reach Earth. Fewer cosmic rays mean fewer clouds will be formed, and so there will be a warmer Earth. If the sun and the solar wind are not so active, then more cosmic rays can come in. That means more clouds [reflecting away more sunlight] and a cooler Earth.

I remember years ago on a very cloudy day, I could see a spot on the sun as it was rising.  Very cool.

I think a lot of people are letting emotion get in the way of good science. 

I am all for conservation but I can't see forcing developing nations to use solar when we don't use it ourselves.

Here's some interesting stuff.



Sometimes they diverge.  I wonder, shouldn't the Earth's magnetic field have something to do with it too?  How about vulcanism?  Could that explain some of divergence?

[Sibling Zono (anon1mat0)]

I am all for conservation but I can't see forcing developing nations to use solar when we don't use it ourselves.

I am quite pessimistic to tell the truth. If the cause of the recent warming is anthropogenic it is impossible to moderate emissions in time before a significant change. According to the IPCC:

The previous IPCC assessment reported a warming trend of 0.6+/- 0.2 degree Celsius over the period 1901 to 2000. Because of the strong recent warming, the updated trend over 1906 to 2005 is now 0.74+/- 0.18 degree C.

IOW the temperature rose above the estimate of the previous IPCC report. According to the article we will experience further warming which could be ameliorated or worsen.

OTOH, if the science is wrong and the stuff that is making the current warming is not anthropogenic, we are simply adding more fuel to an ongoing fire and -more importantly- are royally screwed.

The 'beautiful' part of it is that it is quite hard to know what the short and medium term consequences are going to be. It could be stronger hurricanes, sea level rise, a significant change in global weather, or as someone else predicted, a significant change in sea currents and sea salinity that could even trigger a new ice age.

Whatever is going to happen doesn't look good from this end, and while perhaps is not going to affect us in the short term I do fear that my son and his children will experience the consequences.

[beagle]

Real science or a case of getting your disclaimer in first for when the natural cycle turns?

[Swatopluk]

My predictions/views:
1. It will not change the public views into either direction
2. Constant means don't preclude extremes*
3. You can tell that to the polar bears
4. I still believe the predictions that it will be a very hot summer this year (and no lasting snow next winter, but that is just my guts).

*oscillations between -100° and +100° have the same integral per cycle as a constant 0°

[ivor]

I'm buying into the CO2 thing now.  A ten percent rise in CO2 is just not good.

[Sibling Zono (anon1mat0)]

You'll need to buy into methane too, because that's what's coming after the thawing of the tundra's permafrost. 

[Bob in a quantum-state-of-faith]

You'll need to buy into methane too, because that's what's coming after the thawing of the tundra's permafrost. 

Not to mention, if you raise the average annual temperature enough, the average temperature of the bottom of freshwater lakes will rise too.

So?  You say....

But, trapped in the bottom of countless freshwater lakes is immense tonnage of methane.  Kept there by the low average lake-bottom temperatures.   Raise that temp, and the methane "boils" up out of the water....

[Alpaca]

But, trapped in the bottom of countless freshwater lakes is immense tonnage of methane.  Kept there by the low average lake-bottom temperatures.   Raise that temp, and the methane "boils" up out of the water....

Plus the fact that as a general rule a gas's solubility in water decreases as temperature increases, so we can see where that's going. (Think amount of CO₂ hissing from warm soda bottle vs cold soda bottle.)

[Swatopluk]

And then there are those methane hydrates on the ocean floor that become unstable if not kept at low temperature.

[Bob in a quantum-state-of-faith]

Can anyone say "Venus like conditions?" 

[Swatopluk]

I doubt that it will rain sulphuric acid except maybe if this global cooling plan of shooting sulphur into the high atmosphere is executed 

[Sibling Chatty]

Er, what??

Duz dese guys not unnerstan' grabbity?? Whot goez up iz gunna coem down, an' it might not be happi when it coemz down??

Der.

[Swatopluk]

If ye shoot it up high enough, it will not come down but slowly drift away into outer space, so the aliens can smell the hell we made.
Iirc Benjamin Franklin proposed spreading coal dust for melting snow (black absorbs heat, white reflects it).
But if we proceed the way we do, the great sun dragon will waken soon and spread his wings between Earth and Sun, shielding us (could get a wee bit chilly then but there should be enough nuckular waste to keep us warm and glowing).

[Bob in a quantum-state-of-faith]

I saw a science bit about supervolcanoes a while ago.

It seems that there are still several of these things on Earth, waiting as it were to "strike".

The most recent was roughly 60,000 years ago, and is still active-- that is, it could blow at any time.

The one I'm most familiar with is Yellowstone Park-- the entire park is in the crater of that volcano.

Geologic evidence shows that whenever one of these things blows, the entire world is cooled for roughly 1,000 years or so... very brief in geologic terms....

... but highly significant in human terms.

Wouldn't it be quite ironic, if all our efforts at staving off global warming came to naught, because of a supervolcano blast?  Which enabled a "mini" ice age lasting 1,000 years?

According to the science, the ocean's temperatures averaged 10 degrees cooler... this is enough to kill all but the microscopic life forms in the areas affected.  I imagine the tropics would not be affected as much, but the northern latitudes would be devoid of eatable fish in a year or two.

Whales would not be affected directly-- they are pretty tolerant of variations in temperature individually.  But if their chief food sources vanished?  So would they.

It would be a very different Earth, after a supervolcano eruption.  TOTALLY ignoring the direct effects of the blast itself, obviously...

[Swatopluk]

cynical thought of the day: There won't be many fish to be killed by the event. We will do the job ourselves.

[ivor]

I heard everything below 40 degrees latitude is screwed.

[Griffin NoName]

I heard Southern English Wine Vinyards may be threatened

[mushroomeater]

there should not be any debate on this as clearly as day, global warming is caused by us. if you have watched the inconvenient truth by al gore, it is really bothering.

[Pachyderm]

Actually, global warming is a cyclical process, and has been going on throughout time. What we have done is speed it up.

While I applaud Al Gore's commitment, the vast carbon footprint caused by the constant travelling to spread the word is generally disregarded. Also, the data he presents has been manipulated by some very clever people, and doesn't always portray the exact picture. (eg some of the graphs are extracted from much longer term data sets, and seem to show a large change, but the extracted data is displayed on a different,much smaller,scale. This is not indicated in his speech, and so gives the impession that both the graphs are based on the same scale.

It's a very impressive presentation, and does raise good pints, but as with everything else politically based, needs detailed examination.

[Scriblerus the Philosophe]

There's a lot more than what most people think about--a lot of it is us, but the global temperatures swing back and forth between ice ages and hoter, wetter climes. We just left an ice age not that long ago, so that's part of it.

[Sibling Zono (anon1mat0)]

I was talking to a close friend the other day and he made a point on the subject with which I'm completely in agreement and it's that with the present rate of change and the amount of CO₂ already in the atmosphere, even if we stop producing CO₂ and methane today, we're screwed for the next 50 to 100 years. Add the current political will to do something about it and a looming economic depression and the changes needed will likely be too little too late.

Needless to say I'm very pessimistic on the subject.

[Griffin NoName]

Time for the Global WarNing Thread in Games?

[Swatopluk]

To my knowledge we are technically still in an Ice Age and it is not fully clear whether the next "natural" step would be a return to a true warming period or the next cold peak. Should nature be undecided, we are currently making the decision for her. Although the Gulfstream horror scenario seems to be less probable now, this does not preclude that parts of the world could get a good deal colder before nose-diving into Sahara global (and weather in general getting more extreme).
Apart from the temperature question: Too much CO₂ favors weeds over crops.

Long term goals: reduce mankind to 1 billion people and keep that (without the usual rude methods).
Don't even try to get everyone to US consumption (=waste) level, Europe light may be sustainable for the reduced number of people.
But the first thing we do, let's kill all the lawyers. 

[Griffin NoName]

To my knowledge we are technically still in an Ice Age and it is not fully clear whether the next "natural" step would be a return to a true warming period or the next cold peak. ..................

Long term goals: reduce mankind to 1 billion people and keep that (without the usual rude methods).

May not be necessary. After watching David Attenborough's Cheeky Monkey it seems fairly clear intelligent life will progress and we are merely a divergence that has failed. It may be more important to bring in "Informed Consent" for apes and that would at least shut up the Animal Rights people as well.

[Swatopluk]

Video only available in UK 

[Opsa]

I don't care if it'll take several decades after I die for it all to begin to make a difference environment-wise, we still have to take measures NOW. The alternative is to let it get worse and that is not acceptable. I love the earth.

PS: Hi mushroom eater! Won't you introduce yourself here?

[Sibling Zono (anon1mat0)]

I wondered if creating a new thread in Human Concerns or just keep going on here in this one.
--
According to some scientists at NOAA global warming is irreversible.

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

To me it makes perfect sense (we have now several times the amount of CO₂ compared to the preindustrial age), the hit is on the potential time scale for damage.

[Opsa]

Irreversible, maybe- but if we continue on as we are we will only compound it. That's one of the reasons that the commercial that boasts that the U.S. has enough oil to last a whole 60 years (as if that's forever!) makes me so hopping mad. It is just irresponsible to think we can go on blithely running big fat SUVs like nothing is wrong. I'm glad there's a crisis. It's getting us off our complacency about pollution.

[Scriblerus the Philosophe]

I really, really doubt it's irreversible. After we kill ourselves off, the earth will find equilibrium again.

It scares me how blase so many people are about global warming. As long it's NIMBY, doesn't matter. I think we're seeing some of it around here. The last couple winters, it's gotten warm (like upper 60s) in late December/early January and remains so until about March, when there's a couple weeks of frost. And then it doesn't get warm again until April.
There's already plants blooming right now--they didn't used to until the end of February at the earliest.

This isn't the El Nino/La Nina cycle. We haven't had a wet winter since 1997.

[Sibling Zono (anon1mat0)]

I believe the term 'irreversible' is used in relative terms, that is, regardless of what we do now it will not change much in our lifetimes nor in the lifetimes of our children, grandchildren, etc.

The whole thing got me thinking about carbon sequestration, the idea is to pump the CO₂ in the hollow basin where the oil/gas were, before we pumped it out. Eventually it will go out, so by doing so we are not so much solving a problem (supposedly) but delaying it.

The worst thing is that coal is still very abundant and despite the new effort to move to renewables it still will be used for the foreseeable future. I wonder (and may be the chemistry gods here can tell me) if you can convert coal into plastics instead of burning it, which at least would give some use to the stuff.

[Swatopluk]

Delaying it may be just the thing we need. There are some borderline ideas that once fusion power is available on a (really) large scale, the excess CO₂ could be filtered from the atmosphere and turned to carbon and oxygen again. Just getting it out of the air is energy intensive enough but there is enough hydrogen to fuse around. But efficient fusion power plants are still several decades in the future in even the most optimistic predictions.

[Opsa]

Speaking of climate change, the Washington Post had an article today about a Phenology Study that needs people from all over the US to report in with information about when plants in their area sprout, bloom, whatever. Check the linky if you want to help. They will be conducting another one on animals and other wildlife soon, as well.

I'll put another linky in our gardening and science areas.