The Global Warming Megathread

[Cliff Clavin]

Cutting back on fossil fuel use would certainly make things better. As I mentioned there is a cooling effect due to aerosol compounds. Many of these substances have been banned or fallen out of use, so in effect we already have cut back on them.

 

The IPCC projected a range of possible scenarios for the year 2100... none of them were lead melting, though there is a wide range due to uncertainties about future emissions from sources such as fossil fuel use.

 

Most agree the most probable prediction is a rise of 5.5-6 degrees in the next 100 years globally.

 

 

I think it's in the book "The Long Emergency" by James Howard Kunstler or was it "Power Down" by Richard Heinberg? Anyway it explains why and how this lead melting phenomenon will/could take place by relying on abundant amounts of coal reserves to take place of dwindling Oil and Gas and Uranium for a Electic Addicted society.

 

Although I advocate not to believe everything you read but there is never fire without smoke!

[Cliff Clavin]

And then there is the idea that it's all part of natures long term plan and that nothing we have done or can do has / will make a blind bit of difference.

 

Forget emissions, it's just the next ice age on its way.

 

The magnetic field flipping might be more scary TBH.

 

This is true. There is also the theory that we are actually at the end of the last/current ice age??? This is the reason there is less and less snow, even though there seems to be more in the middle of antartica, everywere else there is less and less and ice caps continue to melt to the point that it all begins again.

[4U2NV]

You're not selfish at all are you.

 

Personally it's attitudes like that that means the world is basically screwed. It doesn't take much to recycle/use less water/switch off things when not using them/use energy efficient lightbulbs etc etc. Thing is most people can't be bothered.

 

I think it's already too late for some off it as from reading around it's the oceans that cause the biggest rise, it's just that they take a long time to heat up but once they do it can happen very quickly. It will also take a long time to reverse any effects.

 

I do what little I can to help.....except for my car, though I only use it maybe once a week as I use public transport and walk to work.

 

Have you know i do you use energy saving bulbs do recycle papar and have a compost heap. we can all try our bit but as long as countries pump out vast amounts of these emissions, little me aint gonna make a differrence.

 

im guessing that you are not a parent?

I am and what 'we' have done to this planet and the short/long term effects of this terrifies me

I try and do my bit,ie recycling,educating my children etc but WISH i could do more.I understand that it may well be too late to stop or reverse the damage but feel that 'we' shouldnt give up?

 

no i aint a parent BUT when countries dont care (not going down the road of anti amercanism) yet it remains the biggest polluter with there 10 litre cars.

[Mathom]

Even if we had done nothing to affect the environment of our planet then it would go through shifts and changes over the centuries, partly due to events like volcanic eruptions (there was one in the 10th or 11th century which caused something like a 'nuclear winter' for some years - can someone point out the date of it, I want to read more about it...). The scary aspect is that we are accelerating change to such a degree that violent weather patterns and much more abrupt changes are likely.

 

We also put ourselves in the line of fire by living in risky areas, such as flood plains - New Orleans? York?

 

This theory about the magnetic fields sounds interesting - might have to look that one up and give myself some more nightmares!

[Greybeard]

Even if we had done nothing to affect the environment of our planet then it would go through shifts and changes over the centuries, partly due to events like volcanic eruptions (there was one in the 10th or 11th century which caused something like a 'nuclear winter' for some years - can someone point out the date of it, I want to read more about it...).

 

Dunno about the 10/11th. century, but there was such an event in the early 6th. century around 540AD. The effects are supported by dendrochronology and there are references to it in written records of the time. There was a BBC TV documentary about it some years ago seeking to prove it was caused by an eruption in the area of Indonesia - perhaps Krakatoa.

[Zafar]

Dunno about the 10/11th. century, but there was such an event in the early 6th. century around 540AD. The effects are supported by dendrochronology and there are references to it in written records of the time. There was a BBC TV documentary about it some years ago seeking to prove it was caused by an eruption in the area of Indonesia - perhaps Krakatoa.

 

 

The David Keys book called Catastrophe.

 

Amazing how many great civilisations came crashing down, and how new ones rose to replace them, especially Islam.

 

Kind of makes you realise how a single 'act of God' can put us back in the dark ages so quickly!

 

Z

[Zafar]

Even if we had done nothing to affect the environment of our planet then it would go through shifts and changes over the centuries, partly due to events like volcanic eruptions (there was one in the 10th or 11th century which caused something like a 'nuclear winter' for some years - can someone point out the date of it, I want to read more about it...). The scary aspect is that we are accelerating change to such a degree that violent weather patterns and much more abrupt changes are likely.

 

We also put ourselves in the line of fire by living in risky areas, such as flood plains - New Orleans? York?

 

This theory about the magnetic fields sounds interesting - might have to look that one up and give myself some more nightmares!

 

 

I heard somewhere that 50% of the worlds population still live something 20miles from the sea, so simply by having rising sea's, alot of people are going to be affected.

 

Makes you wonder that if sea levels have risen in the past, then alot of the past civilisations are under sea rather than underground ?

 

Z

[Zafar]

Zafar: Point of great debate and uncertainty. However it seems pretty much certain that if what we've done so far would warm the world, doing more of it would warm it more - global warming's not an on/off event, it's a sliding scale. Lets not slide it further than we can help.

 

Hi Crayfish,

 

My point is that if we have passed the point of no return, and a set of processes have now been started that are going to play out, such as extreme weather patterns, rising sea levels, possible suspension of the gulfstream weather (mini ice age) etc then maybe we should be looking at how live will be in the coming decades and start to make adjustments now ?

 

Be it the design of our housing, and infrastructure ? Even national security should be re-evaluated ?

 

By all means we still need to do alot more to conserve energy, but we should also perhaps be proactive on alot of other fronts too.

 

Z

[Crayfish]

We're definitely seeing an effect of increasing CO2, quite noticeable over the last 50 years or so - the Keeling curve shows this (started measuring CO2 concentrations 50 years ago, still running). Various measures all agree that there is an incredibly tight, pretty much perfect correlation between CO2 concentration and temperature going back through time, indicating that it is the main driver or at least best proxy measure of global temperature.

 

Ice core data takes us back around 700,000 years now and is thought to be a reliable measure of atmospheric CO2 during this period (they're drilling down to ice that formed this long ago and simply looking at bubbles of trapped air in it). There are various patterns, most linked to milankovitch cycles - but some of the patterns thought to be constant from other, younger ice cores seem to disappear over 450,000 years ago. Everyone confused.

 

Going back way, way through time, CO2 concentration 450 million years ago was about 22 times higher than today. After land plants took hold, it started to fall and there's been a reasonably steady decrease till today (except a rise ca.250 mya). Vegetation has been locking CO2 away as coal, oil and other fossil fuels - and that's what we're now letting back into the air again. During this time, CO2 concentrations were only once (for about 75 million years during the Carboniferous) as low as they are today. However, they're now definitely on the rise again, present concentrations are the highest they have been in the last 110 thousand years or so and they're not showing any signs of coming back down - at present they're around 370 ppm, in 2100 they could well be 800 ppm or more.

 

So it's now agreed things will get warmer, it's just how quickly and the effects of warming that are still being worked out. One problem is that we might see a sort of tipping point where the warming causes increased rates of greenhouse gas release (e.g. by killing off boreal forests, causing the release of seabed methane clathrates - any one, several or all of the many feedback events people have thought of). Probably the hardest thing to predict is what will happen to the weather and the various effects this will have on things that interest us such as water and food availability.

 

As mentioned, more energy means that extreme weather events will be even more extreme. Quite a lot of bad hurricanes this year, very likely to be linked to global warming - not that Bush seems to be taking any notice (Note I don't include all of America in this, several states are taking the initiative on climate change). Talking of places to live, countries often subject to storms, floods etc. are probably not good.

 

Basically, there are various long term cycles (see milankovitch cycles for instance), and random events like volcanoes have large effects - but despite all this, and despite the relatively small amount emitted by humans (total flux 300 Gigatons a year, we release maybe 7 Gigatons per year), we are driving the system out of balance and radically speeding the warming process (some even reckon we're changing the direction, before we started emitting so much there were a few indications we might have been heading for another glacial period).

[Crayfish]

Hi Crayfish,

 

My point is that if we have passed the point of no return, and a set of processes have now been started that are going to play out, such as extreme weather patterns, rising sea levels, possible suspension of the gulfstream weather (mini ice age) etc then maybe we should be looking at how live will be in the coming decades and start to make adjustments now ?

 

Be it the design of our housing, and infrastructure ? Even national security should be re-evaluated ?

 

By all means we still need to do alot more to conserve energy, but we should also perhaps be proactive on alot of other fronts too.

 

Z

 

Yes, sounds like a very good idea - unfortunately because no one is 100% sure what's really going to happen or when, there aren't any timescales or material to make certain plans from:

 

If we designed our houses for maximum solar absorption, massive amounts of insulation etc. in preparation for the gulf stream disappearing, then it stays there and we just get the warming effects, no one would be happy.

 

Only problem is, don't know how much warning we'll get either, things could change quite quickly. It's quite possible we need to be taking action of some sort now, but it's equally possible we don't, and no one knows what sort of action that should be. Only thing (nearly) everyone is agreed on is that reducing emissions would be a good idea. Although practically, I doubt they're going to be reduced enough to make a major difference unless a nice clean energy source to replace fossil fuels is found.