Global Warming

[Wayland]

I've noticed that this topic still causes a great deal of debate amongst the public and politicians so I couldn't help wondering what people thought about it here.

After all, we are more closely connected to the natural world than many other groups in society and generally quite well informed.

So what do you think? "Natural" or "Man Made"? "Cause for Concern" or "Storm in a Teacup"?

I'll hold off till later with my thoughts but if we do get some differences of opinion I hope we can keep it all friendly

 

[Shewie]

In brief ..

Natural & storm in a tea cup

I'm with the opinion that the ice caps will eventually melt, the sea will cool, the Gulf Stream will grind to a halt and the next ice age will begin. Whether we'll still be here to experience it I'm not sure, the way we're destroying this planet it's only a matter of time before it all goes Mad Max

 

[Retired Member southey]

I'm kind of with you there rich, In that I think we have bugger all to do with the cycle of things, anything we are told we should be doing is just to make a buck, or to try a bolster the use use of products that we think we are Dependant on, but as for emission type rubbish i think we are being led up the garden path as to its effects on the planet,

Southey

 

[British Red]

I think its largely irrelevant as:

1)
Recent reearch appears to indicate the possible decline in sunspot activity and a potential correlation with global cooling and the mini ice age

2)
The major problem facing the planet is not per capita consumption but population increase. Unless we tackle that, peak water, peak food etc. will hit much harder than climate change

3)
I'm not covinced, even if we acknowledge climate change as a reality, that the effect here would be one of warming

4)
Hydro carbon are finite and will be used - if not by us then by others. The real challenge is using what is left to cushion the change to a post oil world

5)
The repeated manipulation and faking of climate change data to support an agenda undermines the entire premise of scientific impartiality on this matter

Red

 

[Peter_t]

i agree with the above but what really gets me is that there is such huge taxes on fuel and more so that emmitions have such an effect on road tax. so the goverment is going to use all the tax from land rovers and such on repairing the environment? yeah right!


pete

 

[Toddy]

I think it's two things.

There's the natural cycle.

There's our polution of our environment.

When I was a little girl our cities were black. They were black with soot from every coal fire in the land. Fog was filthy yellow and horrid.
Now, without that, the air's a lot cleaner, cities are showing the colours of their stones, plants grow everywhere, fog's a fun filled mystical time

The litter though, the careless throw away society, the sea dumping of our rubbish That's untenable and needs addressed.

Just my 2p worth.

cheers,
Toddy

 

[charleslockerbie]

im not sure if we caused it but we need to adapt. And we need to reduce population, alternative is earth does it for us.

 

[Silverhill]

Ditto the above comments, but I do feel that (in a way) the media hype will eventually lead to a diversification on reliance of power and minerals, which is a good thing (I hope).

With regards to the bare 'nature' of the subject, and with reference to the Geological timescale, the fluctuations in temperature and climate are a mere nano-blip in the grander scheme of things. You only need to refer to Milankovitch cycles and similar theories to see that the climate data for recorded history bears little or no weight in the overall argument. By all accounts, without global warming the northern hemisphere may have been heading toward glaciation.

Of course, there are many folk who will disagree with this statement, but as a Geologist, I find it hard ignore the evidence under our feet.

 

[Pandabean]

Im also a geologist and looking in geological time you can see there were much warmer & cooler periods than we are in now however what was the human population then compared to now (only in the last couple of centuries has population sky rocketed)? The increase in population means that these natural cycles appear to be more dramatic than they actually are.

Take the recent newspaper report about a possible earthquake happening in the English Channel and that in the 1500s I think it was there were a small handful of people killed by i, but move to today and have the same thing happen more may be injured/killed as a result...why? Because there are more people...and my point? Notice how there are all these natural disasters appearing everywhere, flooded areas, with the population we had quite a while back these would have been natural and less of an issue. We are building on flood plains, in areas not suitable for building so it is getting reported more.

Kind of went a bit off topic and rambled there, but anyway my main thought behind global warming is its is a natural event.

 

[demographic]

I think its largely irrelevant as:

1)
Recent reearch appears to indicate the possible decline in sunspot activity and a potential correlation with global cooling and the mini ice age.

I'm not so sure...

Europe basked in unusually warm weather in medieval times, but why has been open to debate. Now the natural climate mechanism that caused the mild spell seems to have been pinpointed.

The finding is significant today because, according to Valerie Trouet at the Swiss Federal Institute for Forest, Snow, and Landscape Research in Birmensdorf, the mechanism that caused the warm spell in Europe – and meant wine could be produced in England as it is now – cannot explain current warming. It means the medieval warm period was mainly a regional phenomenon caused by altered heat distribution rather than a global phenomenon.

The finding scuppers one of the favourite arguments of climate-change deniers. If Europe had temperature increases before we started emitting large amounts of greenhouse gases, their argument goes, then maybe the current global warming isn't caused by humans, either.

To work out what the global climate was doing 1000 years ago during the so-called "Medieval Warm Period", Trouet and colleagues started by looking at the annual growth rings of Moroccan Atlas cedar trees and of a stalagmite that grew in a Scottish cave beneath a peat bog. This revealed how dry or wet it has been in those regions over the last 1000 years.

The weather in Scotland is highly influenced by a semi-permanent pressure system called the Icelandic Low, and that in Morocco by another called the Azores High. "So by combining our data, which showed a very wet medieval Scotland and very dry Morocco, we could work out how big the pressure difference between those areas was during that time," says Trouet.
Warm blast

This pressure difference in turn revealed that the medieval period must have experienced a strongly positive North Atlantic Oscillation (NAO) – the ocean current that drives winds from the Atlantic over Europe. The more positive the NAO is, the more warm air is blown towards the continent.

The idea to use growth rings to work out past climate change is not new, but Trouet's team is the first to look back beyond 1400 in the European record. They found that the strongly positive NAO lasted for about 350 years from 1050 to 1400.

By combining their data with information from other regions of the world during medieval times and plugging it into different models, the researchers have also come up with a hypothesis of what made the warm winds so persistent.

"It turns out that in the tropical Pacific, the El Niño system was in a negative La Niña mode, meaning it was colder than normal," says Trouet.
Climate loop

El Niño and the NAO are connected by a process called thermohaline circulation, which drives the "ocean conveyor belt" that shuttles sea water of different density around the world's oceans.

According to Trouet, a Pacific La Niña mode and a positive NAO mode could have reinforced each other in a positive feedback loop – and this could explain the stability of the medieval climate anomaly.

Trouet thinks external forces like abrupt changes in solar output or volcanism must have started and stopped the cycle, and hopes to pinpoint the most likely candidates in a workshop with other climatologists in May.
'Profound implications'

Michael Mann at Pennsylvania State University says that based on the analyses and modelling that he has done, increased solar output and a reduction in volcanoes spouting cooling ash into the atmosphere could have not only kicked off the medieval warming, but might also have maintained it directly.

Mann is also concerned that the dominance of medieval La Niña conditions now indicated by Trouet's work might make it more likely that the current man-made warming could also put the El Niño system back into a La Niña mode, although most climate models so far had predicted the opposite.

"If this happens, then the implications are profound, because regions that are already suffering from increased droughts as a result of climate warming, like western North America, will become even drier if La Niña prevails in the future", he says.

Journal Reference: Science (DOI: 10.1126/science.1166349)

There's some very interesting reading in New Scientists "The 7 biggest myths about climate change" article that might give you a good idea of the difference between the popular press and the scientific journals from a layman's point of view, problem is much of its subscriber only, I'll chuck some into the debate every once in a while just to keep the arguments a bit more accurate eh?

 

[ged]

...as for emission type rubbish i think we are being led up the garden path as to its effects on the planet...

Hmmmm. Leaving aside the disputed question of the effects, these, er, inconvenient observations cannot be disputed.

I would hope that people can look at these measurements, take note of the (to me at least) alarming trend, and then ask themselves the obvious questions.

 

[jonnie drake]

I think it's a mixture of all the answers given- I think it's part of a natural cycle that we have helped along, and we should adapt to it cause theres not a lot we can do to change it, theres no reverse button. And like people in power really give a toss? if they wanted to do something about it they would have done a hell of a lot more by now.

 

[Silverhill]

Hmmmm. Leaving aside the disputed question of the effects, these, er, inconvenient observations cannot be disputed.

I would hope that people can look at these measurements, take note of the (to me at least) alarming trend, and then ask themselves the obvious questions.

Without wishing to state the obvious, the figures portrayed by the figure on Wikipedia are derived from the USDE based upon monitoring of gases in the atmosphere ONLY. It does not draw a correlation or suggest any relationships between the amount of carbon released into the atmosphere and the CAUSE of global warming.

One could easily argue that the source of CO2 is irrelevant to the outcome, for example the mid-Cretaceous global warming episode (for which I am sure T-Rex driving to work at the oil refinery in his turbo-charged V8 12-litre gas-guzzler was not to blame ) saw an increase of CO2 increase leading to a change in average temperature between 6 and 14 degrees Centigrade. Whilst I am sure the way in which we have exploited fossil fuels has undoubtedly increased CO2 in the atmosphere in recent times, evidence suggests that our contribution is merely parasitic to a natural 'cycle' or phenomenon.

I think that the real impetus behind the whole argument on Global Warming is that change, as always, is feared by humans. We have not experienced the like of this in the past 500 years or so, thus we are driven into a state of hype over a subject which, given reasonable time and resources, can be researched and understood fully.

 

[ged]

... like people in power really give a toss? if they wanted to do something about it they would have done a hell of a lot more by now.

It isn't 'the people in power' that have to do something about it. It's everybody else.

 

[ged]

I would hope that people can look at these measurements, take note of the (to me at least) alarming trend, and then ask themselves the obvious questions.

Without wishing to state the obvious [obvious stated]...
...and the CAUSE of global warming.

I was trying to leave aside anything contentious.

One could easily argue that the source of CO2 is irrelevant to the outcome

Indeed, the source may or may not be an issue. The amount of the gas in the atmosphere, to me at least, is an issue.

...for example the mid-Cretaceous global warming episode ... saw an increase of CO2 increase leading to a change in average temperature between 6 and 14 degrees

If you say so.

Whilst I am sure the way in which we have exploited fossil fuels has undoubtedly increased CO2 in the atmosphere in recent times, evidence suggests that our contribution is merely parasitic to a natural 'cycle' or phenomenon. ...the real impetus behind the whole argument on Global Warming is that change, as always, is feared by humans. ...

You seem to have a lot of non-obvious answers, but I think I missed the bit where you asked the obvious questions.

a subject which, given reasonable time and resources, can be researched and understood fully.

Well as for time, you have about 40 years. Then the Amazon rain forest will be destroyed by fire, which will put the equivalent of about a decade's worth of human fossil fuel consumption into the atmosphere in the space of about a fortnight. Nobody really knows what will happen then, but I suppose given reasonable time and resources we'll be able to figure it out. Oh, as for resources, the next generation will have approximately nothing to spare. In case you haven't been keeping up with world news, we've borrowed and spent it already.

Sorry about the resources, but is a few decades "reasonable time" for the research?

And if it takes, say a couple of decades to figure it all out, and if the answer turns out to be something, well, inconvenient...

WHAT THEN?

 

[_mark_]

Natural cycles aside it's the anthropogenic influence on our climate that is under scrutiny, cumulative effects etc. For this there are no historical precedents.

 

[locum76]

As BR has said the bigger issues are overpopulation and resource depletion both of which are inevitable in the growth of any species.
(Note: me and my wife are about to have a kid so I'm not going to preach about overpopulation)

Think of humans as bacteria and the earth as a Petri dish and you'll get the picture.

Wayland, you missed out this option on your poll: The earth has a natural warming and cooling cycle which is currently being influenced by human effluent with a notable, additional warming effect. We need to adapt and slow down the rate of accelerated change caused by our influence.

 

[Silverhill]

In line with Waylands initial thoughts on the subject, I think we can agree to keep this a 'discussion' in good nature and not too far off-topic
Depsite this, I'll be the first to put my hand up and admit that this thread is going to raise a stir; I don't think you can avoid being contentious on such a thread as this.

Regarding the atmospheric CO2, can I ask what affect you feel the increased CO2 derived from artificial sources is having versus that of natural CO2?
Harking back to my point regarding the natural cycles versus natural input, if you understand the 4.5 billion years of history locked in stratigraphic record beneath our very feet, you will understand that Global Warming in it's most literal sense occurs frequently (thousands to millions of years in terms of scale), well above the level we are currently or likely to experience in this period. Proof of this can be found in a mutitude of publications by the USGS or, more impartially, the BGS based down the road at Keyworth.

For an example of studies into the above, please consult...;
Model Simulations of Cretaceous Climates: The Role of Geography and Carbon Dioxide by Barron et al,
Climate sensitivity constrained by CO2 concentrations over the past 420 million years, Royer et al.
Extreme polar warmth during the Cretaceous greenhouse?, Bice et al.

....to name but a few. These are proven scientific studies into past episodes of global warming to temperatures far higher than our own, yet life was still flourishing and evolving.

Moving on to resources; The Amazon Rainforest is something I can agree with although I find your belief regarding reserves totally bewildering, possibly as a result of media and hype.
The UK alone has enough Coal for hundreds of years, however the price of imports is 'dirt' cheap and as such it is unprofitable for mining firms to extract our reserves. I do a degree of work for properties which have suffered subsidence and also for site investigation which results in the requirement for coring through the underlying strata. The the amount of coal still left in the ground is surprising when you consider UK Coal are still scrabbling around processing spoil heaps from the late 19th Century. Reserves of Oil, Gas, Coal Bed Methane and Oil Shales are being drilled and developed every day, with the former two in abundant supply.

Proof, if any were needed, can be obtained from your local councils 'Minerals Plan' for the princely sum of £25, or alternatively seek the council of the BGS. Whilst calling the BGS for a friendly chat, why not press them for the data surrounding the Falklands, Afghanistan and Iraq while you're at it. I can assure you it makes a riveting read!!:yikes:

All of the above does not detract from the fact that use of fossil fuels is something that we cannot rely on indefinately, and we must 'wean' ourselves off reliance of finite resources. This period of transition will take time, but time (contrary to your belief) is something we DO have. But time must not be squandered whilst trundling blindly and headlong into an abyss of blackouts and exhausted reserves.

The facts remain, that this debate will go on long after we're all dead, but the question of what to do now...... Well, if I knew the answer, do you think I'd be here now??

 

[Retired Member southey]

Just out of interest can any one tell me how much carbon was thrown into the atmosphere by the largish eruption of the volcano beneath the Eyjafjallajökull glacier in Iceland

 

[Silverhill]

I seem to remember some BGS boffins estimating the eruption emitted a total of 2.5 million tonnes over the period of eruption. How much it continues to produce on a daily basis must be a fraction, but still significant.