Breathing space?

[jethro]

Please can you provide links to peer reviewed papers which validate those assertions GW.

[Gray-Wolf]

C'mon Jethro, we know you have a wish to appear inscrutable from your reluctance to help us understand your meaning but this is just 'out there'.

What am I asserting now? We have a link across on the other 'active' GW thread outlining Oxfam's

http://lifestyle.aol.co.uk/go-green/weathe...125071009990001

release on their increased activities in the 'weather/climate related aid' as compared to the 'stable' earthquake/volcanic outgoings, we've had the worse and most extensive summer flooding the country has know. We've had endless news reports since 2005 on the plight of those who felt they were insured for Katrina's damage only to find out the insurers moved the goal posts ,and ,of course, the first ever recorded snow to fall in Somalia leading to a death from a roof collapse.

Where've you been?

Edited November 26, 2007 by Gray-Wolf

[Devonian]

I recommend that if you want a good idea of where we're going then watch this famous video by Albert Bartlett - retired Professor of Physics at Colorado University:

http://globalpublicmedia.com/lectures/461

Explains the root of all our problems well. Transcript is there too. Well worth a look.

Great vid isn't it - made me take the number 70 much more seriously

[jethro]

C'mon Jethro, we know you have a wish to appear inscrutable from your reluctance to help us understand your meaning but this is just 'out there'.

What am I asserting now? We have a link across on the other 'active' GW thread outlining Oxfam's

http://lifestyle.aol.co.uk/go-green/weathe...125071009990001

release on their increased activities in the 'weather/climate related aid' as compared to the 'stable' earthquake/volcanic outgoings, we've had the worse and most extensive summer flooding the country has know. We've had endless news reports since 2005 on the plight of those who felt they were insured for Katrina's damage only to find out the insurers moved the goal posts ,and ,of course, the first ever recorded snow to fall in Somalia leading to a death from a roof collapse.

Where've you been?

I honestly don't wish to appear inscrutable, nor deliberately obtuse (just seriously busy and lacking time during the day for a fuller reply) but what on earth has the flooding this summer got to do with AGW? We have had similar/worse floods before, we will have them again, there is no proof whatsoever that this had any connection to AGW, now, in the past or indeed, in the future. The problems faced by many of those flooded had far more to do with questionable planning decisions re:building on flood plains, than anything else. Ditto Katrina, experts had warned for years that the defences were not strong enough, had been allowed to fall into a state of dis-repair; again nothing to do with AGW. Snow in Somalia; if I held that up as an example of global cooling, I'd be ridiculed and rightly so, it is proof of nothing. If it is, then the mammouth hail storm in Columbia, the anomously cold temps in the Southern Hemisphere and the large early snowfalls enabling the ski season to begin early this year in the Alps etc, is proof of the end of AGW and the onset of global cooling. It is the linking of each and every weather variation to AGW which causes huge amounts of damage to your argument.

[Chipper]

I honestly don't wish to appear inscrutable, nor deliberately obtuse (just seriously busy and lacking time during the day for a fuller reply) but what on earth has the flooding this summer got to do with AGW? We have had similar/worse floods before, we will have them again, there is no proof whatsoever that this had any connection to AGW, now, in the past or indeed, in the future. The problems faced by many of those flooded had far more to do with questionable planning decisions re:building on flood plains, than anything else. Ditto Katrina, experts had warned for years that the defences were not strong enough, had been allowed to fall into a state of dis-repair; again nothing to do with AGW. Snow in Somalia; if I held that up as an example of global cooling, I'd be ridiculed and rightly so, it is proof of nothing. If it is, then the mammouth hail storm in Columbia, the anomously cold temps in the Southern Hemisphere and the large early snowfalls enabling the ski season to begin early this year in the Alps etc, is proof of the end of AGW and the onset of global cooling. It is the linking of each and every weather variation to AGW which causes huge amounts of damage to your argument.

Perfectly put, Agree 100%.

[Bobby]

I honestly don't wish to appear inscrutable, nor deliberately obtuse (just seriously busy and lacking time during the day for a fuller reply) but what on earth has the flooding this summer got to do with AGW? We have had similar/worse floods before, we will have them again, there is no proof whatsoever that this had any connection to AGW, now, in the past or indeed, in the future. The problems faced by many of those flooded had far more to do with questionable planning decisions re:building on flood plains, than anything else. Ditto Katrina, experts had warned for years that the defences were not strong enough, had been allowed to fall into a state of dis-repair; again nothing to do with AGW. Snow in Somalia; if I held that up as an example of global cooling, I'd be ridiculed and rightly so, it is proof of nothing. If it is, then the mammouth hail storm in Columbia, the anomously cold temps in the Southern Hemisphere and the large early snowfalls enabling the ski season to begin early this year in the Alps etc, is proof of the end of AGW and the onset of global cooling. It is the linking of each and every weather variation to AGW which causes huge amounts of damage to your argument.

Our climate is warming and more heat = more energy and thus more potential for extreme weather events. More specifically, increased warmth means increased evaporation from the land and oceans, thus more moisture in the atmosphere and thus more rain. There are other factors that may influence this of course, in some cases more warmth could mean less rain and less extreme weather events, but it points in general to increased frequency and severity of extreme weather events. Why does this seem so ridiculous, that more heat = more evaporation = more rain? Simple laws of physics we're talking about here.

Nobody is saying that warming caused the floods, but that it may well be one factor in them, a factor that increases their chance and severity.

Edited November 27, 2007 by Magpie

[Admiral_Bobski]

Our climate is warming and more heat = more energy and thus more potential for extreme weather events. More specifically, increased warmth means increased evaporation from the land and oceans, thus more moisture in the atmosphere and thus more rain. There are other factors that may influence this of course, in some cases more warmth could mean less rain and less extreme weather events, but it points in general to increased frequency and severity of extreme weather events. Why does this seem so ridiculous, that more heat = more evaporation = more rain? Simple laws of physics we're talking about here.

Nobody is saying that warming caused the floods, but that it may well be one factor in them, a factor that increases their chance and severity.

One important thing that has been mentioned before but is often overlooked is the fact that the world has become a much smaller place. These days absolutely everything is reported by the media (frequently overhyped so as to sell newspapers) and scientists study a wider range of phenomena over a much greater area than they used to. It is fairly meaningless to start talking about an increase in frequency and severity of weather events when we don't know if they were happening 100, 200, 300 years ago. We may have come through a quiet spell of weather (globally) over the past, say, 50 years or so, but we can't make long term comparisons based on our recent experience.

Simply put, if an uninhabited area suffers a dramatic hurricane once every fifty years then nobody really notices. If you then build a town there and fill it with people the next hurricane may be far more damaging (and far more noticeable!), but that doesn't mean there has been a dramatic increase in the number of hurricanes there - the people who live there may experience more hurricanes, but that's to do with location, not frequency.

:lol:

CB

[Gray-Wolf]

Our climate is warming and more heat = more energy and thus more potential for extreme weather events. More specifically, increased warmth means increased evaporation from the land and oceans, thus more moisture in the atmosphere and thus more rain. There are other factors that may influence this of course, in some cases more warmth could mean less rain and less extreme weather events, but it points in general to increased frequency and severity of extreme weather events. Why does this seem so ridiculous, that more heat = more evaporation = more rain? Simple laws of physics we're talking about here.

Nobody is saying that warming caused the floods, but that it may well be one factor in them, a factor that increases their chance and severity.

Thanks Magpie.

More heat, more energy, more 'dynamics' in the system. Mondy has a post over on 'Science' and advises us it's all about the weather events in 'Blue' but where are the weather events in 'Red'? I would wager that an equal/greater amount of unseasonal/extreme weather occured over the same period so why omit these 'facts'

Insofar as the flooding events this summer. I believe that we will find the cold water 'pulse' as driven by the 'Arctic drift' (as measured by NASA,NSIDC et-al) flowing between Greenland and Sweden had plenty to do with the 'extra' precipitation we recieved (and the rainshadow across europe that this 'wrung out' airmass then produced giving them opportunity fr drought/heatwaves) . If this is proven in way you would accept then you'd have to concede that this is NOT a common event (as was the El-Nino induced European floods a few years back). The flooding had more to do with water table rises than river breaches (though of course those would occur as a by product).

Getting back on thread topic, breathing space (population collapse/decline) where as many people living in areas flooded when these events occured in the past? (I seem to remember a 'sandbagged Cathedral' that had never been flooded in it's history which would suggest a very long 'cycle' if these events have occured before).

Let us also not forget that this was 'summer flooding' (and not a 'flash flood' ,short term,Boscastle type event) and not winter flooding on the back of a 'wet period' raising the water table followed by 3 or 4 days of 'winter rain' (as is the norm in widescale winter flooding).

Here again is the graph of population rise. With so many folk (compared to 50 yrs ago) now occupying areas how can we compare impacts (in the 'real world') with now and then. I feel that would be like saying the last time Yellowstone blew it's top (or Vesuvius)

damage and death wasn't that great so any future erruptions would be the same. The impacts (today) of extreme weather events/climate shifts put a phenominal strain on a country (and individuals) resources which will, in time, lead to impacts on the world markets and aid the collapse of such systems (or has this all happened before too?).

Extreme snow events should not be confused with extreme cold events. More heat ,more evaporation ,more snow (only needs 0c to snow which I would say is not uncommon at altitude when you consider the environmental lapse rates in your thinking). Extreme snow events (IMHO) are a hallmark of 'global' warming though a 'local' event.

One important thing that has been mentioned before but is often overlooked is the fact that the world has become a much smaller place. These days absolutely everything is reported by the media (frequently overhyped so as to sell newspapers) and scientists study a wider range of phenomena over a much greater area than they used to. It is fairly meaningless to start talking about an increase in frequency and severity of weather events when we don't know if they were happening 100, 200, 300 years ago. We may have come through a quiet spell of weather (globally) over the past, say, 50 years or so, but we can't make long term comparisons based on our recent experience.

Simply put, if an uninhabited area suffers a dramatic hurricane once every fifty years then nobody really notices. If you then build a town there and fill it with people the next hurricane may be far more damaging (and far more noticeable!), but that doesn't mean there has been a dramatic increase in the number of hurricanes there - the people who live there may experience more hurricanes, but that's to do with location, not frequency.

:lol:

CB

I have a post on the other 'global warming deniers' thread which is a plea for folk who believe this has all happened (frequently?) before to address. Maybe your the boy for the job?

Edited November 27, 2007 by Gray-Wolf

[Admiral_Bobski]

I have a post on the other 'global warming deniers' thread which is a plea for folk who believe this has all happened (frequently?) before to address. Maybe your the boy for the job?

I'm flattered, but I'm not sure... The main thrust of what I'm saying is that our recent experience doesn't preclude this sort of thing from having happened before. To put it another way, I am not necessarily saying that it unequivocally has happened before, but I am saying that we can't automatically put "extreme weather events" down to global warming because we do not necessarily have the historical data required to make a comparison.

I have not yet heard an argument or read a theory which disproves the possibility of cycles as the main player in current so-called extreme weather events. I can't point to particular episodes in the past which support the viewpoint that cycles are at play, partly because I haven't studied this particular area and partly because I expect that - by the very nature of my argument - past episodes will not have been recorded.

It's a bit of a maddening quandary, really.

:lol:

CB

[Gray-Wolf]

I'm flattered, but I'm not sure... The main thrust of what I'm saying is that our recent experience doesn't preclude this sort of thing from having happened before. To put it another way, I am not necessarily saying that it unequivocally has happened before, but I am saying that we can't automatically put "extreme weather events" down to global warming because we do not necessarily have the historical data required to make a comparison.

I have not yet heard an argument or read a theory which disproves the possibility of cycles as the main player in current so-called extreme weather events. I can't point to particular episodes in the past which support the viewpoint that cycles are at play, partly because I haven't studied this particular area and partly because I expect that - by the very nature of my argument - past episodes will not have been recorded.

It's a bit of a maddening quandary, really.

CB

Stuck between a rock and a hard place eh?

Our 'crux' is that this is 'now' and whether it has happened before (either cyclically or as individual events) it has never happened in our current ,human, setup and so we must consider the 'new' impacts such events hold in store for us all.

Be it drought in the U.S./Africa, Middle Europe/Australia, flooding in Africa,Indonesia, extreme snow events in Germany,Japan,Russia (and it's satellite states) or heatwaves in the Arctic it all impacts on the human global infrastructure and if we are witnessing an increase in such events surely we need plan a global response to this 'changing playing field' and not continue B.A.U.

[Admiral_Bobski]

Stuck between a rock and a hard place eh?

Our 'crux' is that this is 'now' and whether it has happened before (either cyclically or as individual events) it has never happened in our current ,human, setup and so we must consider the 'new' impacts such events hold in store for us all.

Be it drought in the U.S./Africa, Middle Europe/Australia, flooding in Africa,Indonesia, extreme snow events in Germany,Japan,Russia (and it's satellite states) or heatwaves in the Arctic it all impacts on the human global infrastructure and if we are witnessing an increase in such events surely we need plan a global response to this 'changing playing field' and not continue B.A.U.

That's not quite what I meant. You said "it has never happened in our current, human, setup..." but that's not what I was getting at - I am saying that it has quite possibly happened in our current, human, setup but perhaps not in places where humans were actually living. Or even that it has happened to the people of various places before but has never been widely reported by a busybody media (maybe even before the media existed!!).

Are we really witnessing an increase in the number of events, or is it simply that more are being reported? Or that more people are being affected simply by dote of the fact that there is a larger population? Or a combination of both? How can we plan a "global response" to random weather conditions?

[jethro]

Our climate is warming and more heat = more energy and thus more potential for extreme weather events. More specifically, increased warmth means increased evaporation from the land and oceans, thus more moisture in the atmosphere and thus more rain. There are other factors that may influence this of course, in some cases more warmth could mean less rain and less extreme weather events, but it points in general to increased frequency and severity of extreme weather events. Why does this seem so ridiculous, that more heat = more evaporation = more rain? Simple laws of physics we're talking about here.

Nobody is saying that warming caused the floods, but that it may well be one factor in them, a factor that increases their chance and severity.

I know all this but the empirical evidence suggests it's nowhere near as simple, jumping to conclusions doesn't create a clearer picture. According to these folk (who I believe to be accredited, accepted, valid etc), the observed global precipitation pattern was for an increase from the beginning of the 20th century up to the 1980's but has since decreased. If it's a case of simple physics, increased warmth means increased evaporation from land and oceans, then how come when we are supposed to be warmer now than ever, more especially since the 1980's; why has precipitation decreased globally? The Tropics are drying out but the NH is getting wetter, especially during the colder months, some would argue this is more indicative of the Earth preparing for a cool down, after all, higher winter time precipitation should lead to glacier growth. I really don't believe it is as simple as we get warmer, ergo we get wetter.

Oops, forgot the link, doh!

http://www.grida.no/climate/vital/18.htm

Edited November 28, 2007 by jethro

[Bobby]

I know all this but the empirical evidence suggests it's nowhere near as simple, jumping to conclusions doesn't create a clearer picture. According to these folk (who I believe to be accredited, accepted, valid etc), the observed global precipitation pattern was for an increase from the beginning of the 20th century up to the 1980's but has since decreased. If it's a case of simple physics, increased warmth means increased evaporation from land and oceans, then how come when we are supposed to be warmer now than ever, more especially since the 1980's; why has precipitation decreased globally? The Tropics are drying out but the NH is getting wetter, especially during the colder months, some would argue this is more indicative of the Earth preparing for a cool down, after all, higher winter time precipitation should lead to glacier growth. I really don't believe it is as simple as we get warmer, ergo we get wetter.

Oops, forgot the link, doh!

http://www.grida.no/climate/vital/18.htm

It its simple physics but I did say it doesn't apply in all cases as there are other factors in play that may even make the Earth drier than average... but the main issue is not so much increased precipitation globally but more intense precipitation and other weather events (apart from cold). More heat makes the atmosphere more volatile, so why it may not increase total global rainfa;;, it will likely increase the severity of it and may heighten the contrasts - for example summers may become very dry but winters very wet, and some places may become much drier while others much wetter. All that extra energy has to go somewhere. A warmer atmosphere is more volatile than a cooler one - basic fact of physics - and it's volatility in our weather that causes problems.

For example there isn't evidence that the number of hurricanes have increased but certainly evidence that they have increased in intensity.

[jethro]

It its simple physics but I did say it doesn't apply in all cases as there are other factors in play that may even make the Earth drier than average... but the main issue is not so much increased precipitation globally but more intense precipitation and other weather events (apart from cold). More heat makes the atmosphere more volatile, so why it may not increase total global rainfa;;, it will likely increase the severity of it and may heighten the contrasts - for example summers may become very dry but winters very wet, and some places may become much drier while others much wetter. All that extra energy has to go somewhere. A warmer atmosphere is more volatile than a cooler one - basic fact of physics - and it's volatility in our weather that causes problems.

For example there isn't evidence that the number of hurricanes have increased but certainly evidence that they have increased in intensity.

But surely that's assuming a static radiative budget? More heat generated doesn't necessarily mean the same heat retained, does it? There's an assumption that more evaporation = more clouds = more heat retained but as this latest shows, assumptions don't always prove to be correct, empirical evidence should always take precedence over computer models surely?

http://www.sciencedaily.com/releases/2007/...71102152636.htm

[Bobby]

But surely that's assuming a static radiative budget? More heat generated doesn't necessarily mean the same heat retained, does it? There's an assumption that more evaporation = more clouds = more heat retained but as this latest shows, assumptions don't always prove to be correct, empirical evidence should always take precedence over computer models surely?

http://www.sciencedaily.com/releases/2007/...71102152636.htm

I don't know what you're getting at... if the atmosphere is warmer, it will be more volatile as there is more energy in the atmosphere. A more volatile atmosphere means more extreme weather events and more contrasts.

There is empirical evidence, for example there is evidence that hurricanes are becoming more frequent. In the UK, there is evidence that thunderstorms are becoming more frequent and more severe. I also recall a study saying that gales are becoming more frequent in the North Atlantic and the systems there are becoming deeper. Don't have the links at hand at the moment but the research is out there on Google somewhere.

[Admiral_Bobski]

I don't know what you're getting at... if the atmosphere is warmer, it will be more volatile as there is more energy in the atmosphere. A more volatile atmosphere means more extreme weather events and more contrasts.

There is empirical evidence, for example there is evidence that hurricanes are becoming more frequent. In the UK, there is evidence that thunderstorms are becoming more frequent and more severe. I also recall a study saying that gales are becoming more frequent in the North Atlantic and the systems there are becoming deeper. Don't have the links at hand at the moment but the research is out there on Google somewhere.

A few questions. Firstly, how much warmer has the atmosphere actually got? Is that temperature increase actually sufficient to cause more "volatility" in the atmosphere (considering that atmospheric temperatures can increase and decrease a great amount in a single day)?

Also, I think it has been discussed before that hurricanes especially are caused more by differences of temperature (between, say, temperate and polar regions) than by simple increased temperatures. Since the current warming is claimed to be greater at the poles and lesser at the equator, surely that implies that hurricane frequency should decrease (as was proposed in a scientific study earlier this year - here's a link I just found to a USA Today article which mentions it... http://www.usatoday.com/weather/research/2...urricanes_N.htm - the study was done by Gabriel Vecchi of NOAA).

CB

[Bobby]

A few questions. Firstly, how much warmer has the atmosphere actually got? Is that temperature increase actually sufficient to cause more "volatility" in the atmosphere (considering that atmospheric temperatures can increase and decrease a great amount in a single day)?

Also, I think it has been discussed before that hurricanes especially are caused more by differences of temperature (between, say, temperate and polar regions) than by simple increased temperatures. Since the current warming is claimed to be greater at the poles and lesser at the equator, surely that implies that hurricane frequency should decrease (as was proposed in a scientific study earlier this year - here's a link I just found to a USA Today article which mentions it... http://www.usatoday.com/weather/research/2...urricanes_N.htm - the study was done by Gabriel Vecchi of NOAA).

CB

Well, around 0.8c the last time I looked. Whether it's enough to cause "sufficient" volatility and increases in extreme weather events at the moment is another question. But the more it warms the more volatality and more extreme weather events. They will become "sufficient" at some point that's for sure.

As for the second part.... read my post again. I never said hurricanes increased in frequency but in intensity.

Let's just imagine some scenarios:

1 - The average Earth temperature is -50c. What would the weather be like then? There wouldn't really be any weather whatsoever. It would be a cold, dead still world. There would be almost no clouds, almost no precipitation, almost no wind. There would be no hurricanes as the oceans would have frozen up. There would be no thunderstorms (or virtually none). The only extreme weather would be the cold. Otherwise, there'd be no weatherto speak of. Day after day in almost every part of Earth it would be cystal clear blue skies, no wind and bitterly cold.

2 - The average Earth tempearture is +50c. What would the weather be like then? Interesting to say the least. The heat would produce intense evaporation - the oceans could even start to boil in places. Convection would be intense. The enormous heat and moisture would trigger downpours and thunderstorms of unimaginable proportions. Hurricanes could develop with average windspeeds over several hundred miles per hour.

There would be floods of unimaginable scales. The jet stream could become far stronger and at higher latitudes deep depressions that make the 1987 storm look like a gentle breeze would sweep by frequently.

Suffice to say, there would be a LOT more extreme weather, and much more intense. So extreme that most of the planet would become effectively uninhabitable. People could only cling on towards to the poles.

Also, more heat doens't necessarily mean more hurricanes or even more intense hurricanes (though unlikely), but if the extra energy doesn't go into making more intense or frequent hurricanes it must go somewhere else. Why do we get more thunderstorms during the summer? Because it's warmer. Why are there more thunderstorms in Europe than in the UK? Because it's warmer

To say that a warmer atmosphere doesn't translate into more extreme and volatile weather is just wrong, as you can't argue with Mr. Physics.

Edited November 28, 2007 by Magpie

[jethro]

But none of those extremes helps to un-ravel expected changes due to minor increases in temps. Maybe we could get Mr. Data in on the act, if he could provide a list of hottest years which were not El Nino years, we could perhaps see if there were any increases in any particular kind of global weather.

[Bobby]

But none of those extremes helps to un-ravel expected changes due to minor increases in temps. Maybe we could get Mr. Data in on the act, if he could provide a list of hottest years which were not El Nino years, we could perhaps see if there were any increases in any particular kind of global weather.

Well, the changes are there. I doubt you'd see much during a El Nino year as the overall difference in heat isn't that much, though I'm sure it would be there to a degree.

[Admiral_Bobski]

Well, around 0.8c the last time I looked. Whether it's enough to cause "sufficient" volatility and increases in extreme weather events at the moment is another question. But the more it warms the more volatality and more extreme weather events. They will become "sufficient" at some point that's for sure.

As for the second part.... read my post again. I never said hurricanes increased in frequency but in intensity.

Actually you did (and I read your post again, just to make sure! ):

There is empirical evidence, for example there is evidence that hurricanes are becoming more frequent. In the UK, there is evidence that thunderstorms are becoming more frequent and more severe. I also recall a study saying that gales are becoming more frequent in the North Atlantic and the systems there are becoming deeper. Don't have the links at hand at the moment but the research is out there on Google somewhere.

Since these supposed increases in frequency are attributed to global warming then we can safely say that the assertion is that increased warming will lead to increased frequency of such events.

Also, more heat doens't necessarily mean more hurricanes or even more intense hurricanes (though unlikely), but if the extra energy doesn't go into making more intense or frequent hurricanes it must go somewhere else. Why do we get more thunderstorms during the summer? Because it's warmer. Why are there more thunderstorms in Europe than in the UK? Because it's warmer

To say that a warmer atmosphere doesn't translate into more extreme and volatile weather is just wrong, as you can't argue with Mr. Physics.

As I said before, increased warmth is only part of the equation - temperature differences tend to lead to more active weather. Certainly there comes a point where the atmosphere is turbulent enough to cause these events through energy alone, but is an increase of less that 1C really sufficient when the difference between daytime and nighttime temperatures can easily be ten times that amount?

CB

[Bobby]

Ah... that was a mistype. As I said in the previous post

For example there isn't evidence that the number of hurricanes have increased but certainly evidence that they have increased in intensity.

..

As I said before, increased warmth is only part of the equation - temperature differences tend to lead to more active weather. Certainly there comes a point where the atmosphere is turbulent enough to cause these events through energy alone, but is an increase of less that 1C really sufficient when the difference between daytime and nighttime temperatures can easily be ten times that amount?

It's only part of the equation yes, but it is the driving force - the overriding factor in extreme weather, after all with no heat there is no weather at all.

As for is it sufficient yet... well, 1c is averaged across the world. Some regions such as those at higher latitudes have warmed significantly more than that. I don't understand what relevance day and night temperature variations have in regard to overall temperature? It's the changes in overrall climate that we are talking about, not daily variations.

There certainly seem to be changes though they aren't particularly large yet but will continue to increase if the temperature does...

[Stratos Ferric]

That's not quite what I meant. You said "it has never happened in our current, human, setup..." but that's not what I was getting at - I am saying that it has quite possibly happened in our current, human, setup but perhaps not in places where humans were actually living. Or even that it has happened to the people of various places before but has never been widely reported by a busybody media (maybe even before the media existed!!).

Are we really witnessing an increase in the number of events, or is it simply that more are being reported? Or that more people are being affected simply by dote of the fact that there is a larger population? Or a combination of both? How can we plan a "global response" to random weather conditions?

It is a fair point, though I suspect reflected rather more in the public perception than in the record of fact - though the latter undeniably will be effected by the density of people sensing and recording across the face of the planet. Percpetually there is far more bandwidth for reportage nowadays, and more technology and personnel to go and capture, and feed back quickly, real time events.

Any form of data capture is always prone to the effect of the measurement and recording itself. For example, capturing crime stats is difficult because once people know you're doing it they can become more inclined to report. And hospital super-bugs have always been around - perhaps not so virulently as seems to be the case now - but once the media gets ahold of the fact they over report, hence a perception that events are more frequent than actually they are (the same CAN be argued re fear of serious assault for example).

I know all this but the empirical evidence suggests it's nowhere near as simple, jumping to conclusions doesn't create a clearer picture. According to these folk (who I believe to be accredited, accepted, valid etc), the observed global precipitation pattern was for an increase from the beginning of the 20th century up to the 1980's but has since decreased. If it's a case of simple physics, increased warmth means increased evaporation from land and oceans, then how come when we are supposed to be warmer now than ever, more especially since the 1980's; why has precipitation decreased globally? The Tropics are drying out but the NH is getting wetter, especially during the colder months, some would argue this is more indicative of the Earth preparing for a cool down, after all, higher winter time precipitation should lead to glacier growth. I really don't believe it is as simple as we get warmer, ergo we get wetter.

Oops, forgot the link, doh!

http://www.grida.no/climate/vital/18.htm

I doff my cap to your ever increasing expertise jethro.

One reason why a warmer world COULD also be drier is simply down to the fact that warmer air can retain more moisture. You make good points though re many complex feedback loops, and the debate re clouds has been raging for a long while.

Not sure how "drier world" is established, but I wonder whether another possibility is that an increasing proportion of rainfall is occurring over oceans.

[jethro]

It is a fair point, though I suspect reflected rather more in the public perception than in the record of fact - though the latter undeniably will be effected by the density of people sensing and recording across the face of the planet. Percpetually there is far more bandwidth for reportage nowadays, and more technology and personnel to go and capture, and feed back quickly, real time events.

Any form of data capture is always prone to the effect of the measurement and recording itself. For example, capturing crime stats is difficult because once people know you're doing it they can become more inclined to report. And hospital super-bugs have always been around - perhaps not so virulently as seems to be the case now - but once the media gets ahold of the fact they over report, hence a perception that events are more frequent than actually they are (the same CAN be argued re fear of serious assault for example).

I doff my cap to your ever increasing expertise jethro.

One reason why a warmer world COULD also be drier is simply down to the fact that warmer air can retain more moisture. You make good points though re many complex feedback loops, and the debate re clouds has been raging for a long while.

Not sure how "drier world" is established, but I wonder whether another possibility is that an increasing proportion of rainfall is occurring over oceans.

Well, thank you SF, I think I should at least get some brownie points for researching and trying to understand all the science, I do always try not to come at this blindly.

As for your other points, don't know about more moisture in the air, theoretically yes but are there any humidity records/indexes - not a clue and no time now to have a look but I will and get back to you. Can't think of a mechanism which would cause increased precipitation to be greater over oceans than land (at least none which would not have historically been there) however the ocean measurements are sparse in comparison to land based ones. Clouds are probably one of the biggest areas of unknowns, certainly in the climate models; we can but hope as more research is done, more info will be fed into the system.

[Gray-Wolf]

why do folk want to know 'average global temp increases' when we are talking local extreme weather events? I would imagine it'd tell us very little but listening to folk from the 'polar year team' enduring temps (over the 6 weeks they were there) of 15c above the 'mean' for that time of year, talk of them watching hillsides succumb to solufluction and flow down into valleys, of being rained on at the geographic pole give me pause for thought. What about you (or have these hillsides that are now bare rock 'seen it all before' and if so how did they grow their soil/peat back last time???).

[The PIT]

I thought we were talking about bugs wiping out most of the human race and how that would effect the climate if at all. Seems to gone back to the normal GW debate.

Going back to the original subject. The other day I was watching Breakfast and there's a shortage of skilled Captains to manage all those oil tankers. Of course reduce the population by a lot and there wouldn't be any oil shipping round the planet. So the lights would go out transport would stop. Of course you may be lucky and have a pipeline but who would be there to maintain it let alone man it. As the West gets more dependant on technology the more vulnerable it becomes. In my book the bushman in Africa would be in prime position barring aids.