Equator/Pole Temperature Differential - the real issue

[Calrissian]

Hi all, with yet another little story in the news about Global warming, I thought I might be daring enough to start off a specific post on something that occured me long ago.

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The climate is currently changing (yes, I realise thats ALWAYS been the case), even so we're now in a decidedly warming phase, that much is fact.

The key issue I think is generally being overlooked - especially by the media (no surprise there), is that the warming is uneven. Oh, and yes, I realise some areas are arguably cooler lately - south Antarctic, right ?

A few questions?

1. Is the average temp diff. between the poles and equator the same over the last decade or so, or has it changed?

2. If the temperate zone and tropics warm slower than the poles, we can assume less active storms/weather, since the very reason we have ALL weather is that of imbalance between different places.

A stray thought of course, is that even if the differential is not as much, there is a lot more heat/energy in the global system - since more is being held by the planet, and so that might still allow for stronger/greater number of storms in the longer term.

Am I right in thinking then that the absolute worse case scenario is that not only might we have a warmer climate, but that the pole/equatorial differential will be higher and individual weather events will thus become more intense?

-----

I am highly interested in what all of you think about this, and whether any of you have any basic numbers about the differential temps, I'm very curious to know.

Calrissian: holding at DEFCON 2

[parmenides3]

Hi all, with yet another little story in the news about Global warming, I thought I might be daring enough to start off a specific post on something that occured me long ago.

--

The climate is currently changing (yes, I realise thats ALWAYS been the case), even so we're now in a decidedly warming phase, that much is fact.

The key issue I think is generally being overlooked - especially by the media (no surprise there), is that the warming is uneven. Oh, and yes, I realise some areas are arguably cooler lately - south Antarctic, right ?

A few questions?

1. Is the average temp diff. between the poles and equator the same over the last decade or so, or has it changed?

2. If the temperate zone and tropics warm slower than the poles, we can assume less active storms/weather, since the very reason we have ALL weather is that of imbalance between different places.

A stray thought of course, is that even if the differential is not as much, there is a lot more heat/energy in the global system - since more is being held by the planet, and so that might still allow for stronger/greater number of storms in the longer term.

Am I right in thinking then that the absolute worse case scenario is that not only might we have a warmer climate, but that the pole/equatorial differential will be higher and individual weather events will thus become more intense?

-----

I am highly interested in what all of you think about this, and whether any of you have any basic numbers about the differential temps, I'm very curious to know.

Calrissian: holding at DEFCON 2

Technically, it is not global warming which is uneven - that is the measure of the rate of change of the climate over the whole globe - but the effects of global warming certainly are. This is the essence of Roger Pielke's argument that climate change should be addressed at regional, not global levels.

For starters:

1. The Arctic is warming about three times faster than the tropics. This is expected. Someone else can give you the absolute mean temp. differential. There are signs of changes in the Antarctic, but there has been little change in temps registered at ground level so far. This is also expected.

2. Not exactly. There are a load of teleconnections you need to take into account, things like a weakening Walker circulation, changes in the Hadley circulation, AO, NAO, etc. etc.. also, consider the role of SST in storm formation and development. If the sea is getting warmer further North, systems can last longer and travel further.

stray thought; the jury is out on this one. perhaps 'possibly', maybe 'probably'.

Your worst case scenario? Check out the Hansen paper posted yesterday on the GW thread, and compare.

hope this helps.

:)P

Edited September 27, 2006 by parmenides3

[The Penguin]

. . . . I realise some areas are arguably cooler lately - south Antarctic, right ? . . . .

Sorry, but that made me smile. Like how much cooler can it be in south Antartica than, say, north Antartica?

[Calrissian]

I was thinking 'south' and 'Antarctic', just so happened I like those words together.

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I just read the Hansen paper, pretty much the same old stuff as usual. I noticed he did mentioned that the high lattitudes of the Northern Hemisphere are warming fastest. So, that'd mean the overall difference between the equator and the north polar region is less....with less activity. Hmm.

Too many variables really, so it will probably all be entirely speculative.

Calrissian: living a little close to sea level.

[parmenides3]

I was thinking 'south' and 'Antarctic', just so happened I like those words together.

----------

I just read the Hansen paper, pretty much the same old stuff as usual. I noticed he did mentioned that the high lattitudes of the Northern Hemisphere are warming fastest. So, that'd mean the overall difference between the equator and the north polar region is less....with less activity. Hmm.

Too many variables really, so it will probably all be entirely speculative.

Calrissian: living a little close to sea level.

It probably won't sway you, but most of the climate modellers reckon that weather events will become more extreme in some parts of the world, but less so in others. Hansen's speculations about 'super-el Ninos' is intersting in this respect; if we start to get a regular and more frequent pattern of +3 ENSO events, it certainly would create more extremes. It's a big 'if'.

:)P

[Gray-Wolf]

I was thinking 'south' and 'Antarctic', just so happened I like those words together.

----------

I just read the Hansen paper, pretty much the same old stuff as usual. I noticed he did mentioned that the high lattitudes of the Northern Hemisphere are warming fastest. So, that'd mean the overall difference between the equator and the north polar region is less....with less activity. Hmm.

Too many variables really, so it will probably all be entirely speculative.

Calrissian: living a little close to sea level.

But not a useless excercise eh?

Do the poles warm more rapidly because they are 'shedding ' their cold or are the equitorial/temperate regions rapidly able to both dissipate their extra heat burden(due to heat retention from greenhouse gas build up) north whilst absorbing the displaced 'cold' polar airs with little or no effect on their (slower) rise in temperature. Maybe the slowness (relative) of their warming is a direct indicator of the absorbtion and warming of the displaced Polar airs?

Edited September 27, 2006 by Gray-Wolf

[parmenides3]

But not a useless excercise eh?

Do the poles warm more rapidly because they are 'shedding ' their cold or are the equitorial/temperate regions rapidly able to both dissipate their extra heat burden(due to heat retention from greenhouse gas build up) north whilst absorbing the displaced 'cold' polar airs with little or no effect on their (slower) rise in temperature. Maybe the slowness (relative) of their warming is a direct indicator of the absorbtion and warming of the displaced Polar airs?

Inevitably, G-W, it's more complex than that. A percentage of the extra warming is due to feedback mechanisms such as surface albedo and water salinity, cloud and water vapour, as well as tropospheric and stratospheric fluxes. I don't think the Polar air is 'going' anywhere, it's just not cooling down, for example at night, or in the Autumn, as quickly as it used to. Whilst there is evidence of a greater volume of warmer water entering the Arctic Ocean, it also leaves it, through the usual channels, mainly disgorging into the North Atlantic.

:)P