Welcome to the new version of European Tribune. It's just a new layout, so everything should work as before - please report bugs here.

Global warming, European cooling? [Updated!]

by Frank Schnittger Wed Dec 8th, 2010 at 08:30:57 AM EST


Sunrise in Wicklow: the view from my home

I returned from Malawi and Kwazulu Natal in South Africa from temperatures up to 35 degrees (with high humidity due to the rainy season) and with that feeling of heat augmented by a slight fever caused by an airport/airplane air-con induced cold - to a cold and snowy Ireland with temperatures down to a record -16 degrees and record snowfalls for late November/early December.  I was very lucky to be able to land between Dublin airport closures and get a lift home (altitude 700 feet) only to find it under up to two feet of snow and with no prospect of moving my car from behind 400 metres of two feet and higher snowdrifts.



Thanks for the lift!

Winters in Ireland had been becoming progressively milder with no "sticking" snow some winters - until the last two - which were exceptionally cold and long lasting.  But we have never seen snow like this in late November early December before.  As I write this, (a week after landing) it is still snowing heavily and the only means of getting anywhere near a main road is on foot or by tractor.

I love snow, find it extraordinarily pretty and peaceful, and enjoy the sense of isolation it can convey.  I can always blog, listen to the radio, and have even started to switch on the TV again occasionally, having previously almost given up on it as a source of news or entertainment.  Most of the (voluntary) work I do can be done by internet/e-mail/phone although the list of missed meetings is starting to grow.  So I am not one to belly-ache about the disruption caused by snow although I appreciate the problems experienced by those who must travel for work/school or to acquire the basic necessities for life.  A three mile walk through snow/ice is not much of a hardship if you are fit and well but almost impossible if you are not.

However I am really appreciative of the home insulation project I undertook last spring which has meant that a previously inadequate (carbon based) home heating system is keeping the house comfortable and I can now look forward to some reduction in my carbon footprint and cost base as well. Unfortunately neither a thermal solar panel or domestic windmill would have been of much benefit during the current (calm and cloudy) cold spell with the roof covered by snow and under soil based heat pumps are still prohibitively expensive to retrofit.  So the search for an even moderately cost effective and more carbon neutral heat source goes on.

Having more time on your hands than usual also gets you thinking about whether there is any longer term significance in this change in weather patterns. Yes, I know all the usual caveats about climate change science being about long term trends and that you cannot claim statistically significant correlations between short term weather patterns and longer term climate trends.  There have been ice ages and mini-ice ages caused by reduced sun spot activity and all sorts of other terrestrial factors long before any anthropogenic climate changes become an issue.

But the particular phenomenon that has tickled my interest of late is the possibility that Global warming and the melting of polar ice caps may actually result in a cooling of Ireland and western Europe through a weakening of the North Atlantic Drift (NAD) which brings warm waters and winds to Ireland and western Europe and results in us having a much milder climate than other regions at a similar latitudes such a Newfoundland.

The NAD is driven by the natural circulation of ocean waters caused by prevailing westerly winds, the Coriolis force, temperature and salinity differences, and tides caused by the gravitational pull of the Moon and the Sun.  It is the salinity differences engine behind the NAD - a phenomenon known as Thermohaline circulation, which is said to be under threat from global warming.

Thermohaline circulation - Wikipedia, the free encyclopedia

The term thermohaline circulation (THC) refers to the part of the large-scale ocean circulation that is driven by global density gradients created by surface heat and freshwater fluxes. The adjective thermohaline derives from thermo- referring to temperature and -haline referring to salt content, factors which together determine the density of sea water. Wind-driven surface currents (such as the Gulf Stream) head polewards from the equatorial Atlantic Ocean, cooling all the while and eventually sinking at high latitudes (forming North Atlantic Deep Water). This dense water then flows into the ocean basins. While the bulk of it upwells in the Southern Ocean, the oldest waters (with a transit time of around 1600 years) upwell in the North Pacific (Primeau, 2005). Extensive mixing therefore takes place between the ocean basins, reducing differences between them and making the Earth's ocean a global system. On their journey, the water masses transport both energy (in the form of heat) and matter (solids, dissolved substances and gases) around the globe. As such, the state of the circulation has a large impact on the climate of the Earth.

So what is the possible impact of global warming on the thermohaline component of the engines which drive the NAD?

Shutdown of thermohaline circulation - Wikipedia, the free encyclopedia

There is some speculation that global warming could, via a shutdown or slowdown of the thermohaline circulation, trigger localised cooling in the North Atlantic and lead to cooling, or lesser warming, in that region. This would particularly affect the areas of the British Isles and the Nordic countries that are warmed by the North Atlantic drift.

Basically, the theory postulates that increased freshwater released by melting polar icecaps will reduce the density of polar waters, preventing them from sinking to the deep ocean basins, and thus interfering with one of the crucial components of the engines driving the global oceanic circulatory system. If polar waters don't sink to the ocean floor, they will effectively block or slow down surface waters flowing north as part of the NAD. This is believed to have happened before, during previous ice-ages - particularly in Europe:

Shutdown of thermohaline circulation - Wikipedia, the free encyclopedia

Some even fear that global warming may be able to trigger the type of abrupt massive temperature shifts which occurred during the last glacial period: a series of Dansgaard-Oeschger events - rapid climate fluctuations - may be attributed to freshwater forcing at high latitude interrupting the THC. The Younger Dryas event may have been of this sort, too. (See the discussion of chaos theory for related ideas.) However, these events are believed to have been triggered by massive freshwater discharges from the Laurentide ice sheet, rather than from the melting of polar sea-ice and precipitation changes associated with the increased open water in global warming.

So is there any evidence that this might be happening now?

Shutdown of thermohaline circulation - Wikipedia, the free encyclopedia

In April 2004, the hypothesis that the Gulf Stream is switching off received a boost when a retrospective analysis of U.S. satellite data seemed to show a slowing of the North Atlantic Gyre, the northern swirl of the Gulf Stream.[7]

In May 2005, Peter Wadhams reported to The Times about the results of investigations in a submarine under the Arctic ice sheet measuring the giant chimneys of cold dense water, in which the cold dense water normally sinks down to the sea bed and is replaced by warm water, forming one of the engines of the North Atlantic Drift. He and his team found the chimneys to have virtually disappeared. Normally there are seven to twelve giant columns, but Wadhams found only two giant columns, both extremely weak.[8][9]

----snip

 The NewScientist.com news service[13] reported on 30 November 2005 that the National Oceanography Centre in the UK found a 30% reduction in the warm currents that carry water north from the Gulf Stream from the last such measurement in 1992.

----snip

Detlef Quadfasel reinforces the point that the uncertainty of the estimates of Bryden et al. is high, but says other factors and observations do support their results. Quadfasel continues by pointing out the significance of the possible implications, with palaeoclimate records showing drops of air temperature up to 10 °C within decades, linked to abrupt switches of ocean circulation when a certain threshold is reached.

There doesn't appear to be enough conclusive evidence at the moment to generate a scientific consensus, and in any case, the global impact of global warming may mask or overwhelm any local cooling caused by a weakening of the NAD. [Update: see last paragraph.]

However there are two points to note:

  1. Paleoclimatic records indicate that quite dramatic changes in temperature have occurred wery rapidly in the past. A 10 °C change in average temperatures in north western Europe could trigger a mini-ice age, and these changes have occurred within decades in the past.

  2. The scope of global climate change could be much greater than the changes which resulted in freshwater discharges in the past resulting in an increased frequency of extreme weather events and a much greater variability in the European climate.

Climate change is thus not a very gradual process of increasing average global temperatures, but could result in very dramatic and rapid fluctuations in particular regions of the globe.  It appears from the paleoclimatic records that the European climate is particularly unstable and prone to such rapid fluctuations. By the time sufficient evidence accumulates to demonstrate that a localised cooling event is happening in Western Europe, we could be well on the road to another ice age.

[Update] More recent evidence - highlighted by Nomad in the comments below - indicates that any previously observed variability in the NAD and deep water currents is within the natural and ongoing variability observed for those currents, and there is as yet no evidence of any long term trends. Indeed it could be as late as 2030-2050 before we have sufficient trend data to draw such conclusions in any case. The current scientific consensus is therefore that the NAD is not weakening, and also that, even if it did, it would not, of itself, be sufficient to cause another mini-ice age.

Phieu! That's a relief! And just to prove it, the snow has begun to melt...:-)

Display:
there are better explanations than the legendary Gulf Stream breakdown for the current coolish autumn.

My first stop on climate questions is always the excellent RealClimate, collective blog of the "hockey team" (i.e. the Hansen crowd)

That pointed me here, to a much more plausible mechanism for global warming causing the cold weather : a combination of the North Atlantic Oscillation and an exceptionally low level of sea ice in the eastern Arctic :

Typically cold weather in northern Europe is associated with the NAO which consists of a high pressure system over the Azores and a low pressure system over Iceland. The so-called negative phase of the NAO was particularly strong during the second half of November, according to Petoukhov. The NAO is the dominant mode of atmospheric variability in the north Atlantic throughout the year and particularly prominent in the winter. The pressure difference drives the winds and the weather fronts.
[...]
"We had a strong negative phase of the NAO in the second half of November. The pressure gradient between the Azores high and the Icelandic low was very small. This is the favourite situation for cold winters

So, we have the NAO which is an apparently random/cyclical type thingy, giving us a bit of a chill this year... But there's more!

Warming oceans, thought by many to be associated with climate change, are contributing to reductions in sea ice in the Arctic area. Computer models suggest that a reduction in sea ice in the eastern Arctic leads to a loss of ocean heat and a consequent warming of the lower atmosphere which can trigger atmospheric circulation anomalies that can in turn lead to an overall cooling of northern continents, according to Petoukhov's research which was published in the Journal of Geophysical Research in November. This can result in a continental-scale winter cooling reaching, on average, −1.5C colder than it would otherwise have been.
[...]
"Just yesterday I checked the sea ice in the Barents-Kara and it was very low. Nearly as low as it was between 2005 and 2006," Petoukhov told Reporting Climate Science .Com on 2 December 2010.

The strong diminishing trend in Arctic sea ice, particularly when it is accentuated in the Barents sea, gives us colder winters. This year it looks like we get the Quinella.

This correlation between the sea ice reduction and the continental cooling is strong, according to the research. Other explanations linking cold winters and global warming include reduced solar activity and changes in the Gulf Stream are less strongly correlated. However, the NAO could interact with sea-ice decrease, the study concludes and one could amplify the other. This is what may be happening at the moment, suggested Petoukhov.

If the Gulf Stream gets messed up as well, that would be the Trifecta. But even without it, I think we'll have a very cold winter.

Footnote : I was hoping to do a bit of early skiing this weekend with the kids... but it's a tepid 15° today, and it's all turned to mush. The joys of a semi-continental climate.

It is rightly acknowledged that people of faith have no monopoly of virtue - Queen Elizabeth II

by eurogreen on Wed Dec 8th, 2010 at 10:18:05 AM EST
More cold winters ahead

Petoukhov believes that we may already be seeing evidence of an increase in the frequency of cold winters compared with the more random, or stochastic, distribution of cold winters in previous decades that were associated with the NAO. "We have already had two chilly winters in Europe in the last decade, and this November situation, as it developed, also forces us to be on the alert. This makes it questionable that only a purely stochastic mechanism of the European cold winter extremes is at work, and this deserves an exhaustive investigation," he commented.

The possibility suggested by Petoukhov that the Barents-Kara Sea effect could triple the probability of cold winter extremes in Europe,will almost certainly be of interest to policy makers and planners in north European states such as the UK where there is an ongoing debate about the level of investment required to deal with "occasional" cold weather events.

Policy implications of colder European winters :

  • Insulation, insulation, insulation
  • Reinforced, weatherproof public transport : a reshag of infrastructure specs (what about the Dublin metro?)
  • Energy security :  oh bugger, Ireland is in the poo on that one. Your home heating problem on a national scale.


It is rightly acknowledged that people of faith have no monopoly of virtue - Queen Elizabeth II
by eurogreen on Wed Dec 8th, 2010 at 10:42:47 AM EST
[ Parent ]
I don't think it is a case of either/or.  There are numerous factors at work and I chose to highlight one.  What I found interesting, as a non climate scientist, is the quite drastic effect relatively small changes in average global temperatures can have in particularly regions, and the degree to which even non-anthropogenic climate change has, in the past, led to quite sudden and dramatic changes in Europe in particular.

Petoukhov talks of other correlations being stronger, but the excerpts you quote don't really provide a theory of causation which explains why low ice in the East Arctic should result in colder winters in NW Europe and doesn't exclude the possibility of global warming ->low Arctic sea ice -> reduced thermohaline circulation -> weaker NAD -> colder winters.

In any case, I'm not qualified to debate the finer points of the available evidence and theories. My purpose was to demonstrate that whilst you cannot prove that exceptionally cold winters in NW Europe are caused by global warming, you cannot exclude that possibility either, and there is no reason why slow and gradual global trends cannot lead the sudden and dramatic localised fluctuations.

Index of Frank's Diaries

by Frank Schnittger (mail Frankschnittger at hot male dotty communists) on Wed Dec 8th, 2010 at 11:15:25 AM EST
[ Parent ]
I find the evidence fairly compelling that there is a causal link between global warming and colder European winters. For the rest, I agree with you completely.

Thanks for the excuse to update my understanding of this subject...

Anyway, if you won't believe me (and who could blame you), perhaps you'll believe...

the UK Met Office?

It is rightly acknowledged that people of faith have no monopoly of virtue - Queen Elizabeth II

by eurogreen on Wed Dec 8th, 2010 at 12:01:44 PM EST
[ Parent ]
Meteorological office for anything.  

Just not relevant.  

I don't mean to pick on the UK--I wouldn't believe the US either.  

From your link

according to Vicky Pope, Head of Climate Change for Government at the UK Meteorological Office
 

Not to be rude, but lying is their job.  

The Fates are kind.

by Gaianne on Thu Dec 9th, 2010 at 02:56:52 AM EST
[ Parent ]
Gaianne:
Not to be rude, but lying is their job.  

I'm not sure I understand why this has to be the case.  What are the institutional/class interests which are served by falsifying climate science?

Index of Frank's Diaries

by Frank Schnittger (mail Frankschnittger at hot male dotty communists) on Thu Dec 9th, 2010 at 04:34:03 AM EST
[ Parent ]
One that has popped up here in Sweden:

* Water security

Water supplies, purification and distribution is adapted to current conditions. Adaptation is needed.

A vote for PES is a vote for EPP! A vote for EPP is a vote for PES! Support the coalition, vote EPP-PES in 2009!

by A swedish kind of death on Wed Dec 8th, 2010 at 04:25:13 PM EST
[ Parent ]
Reversed flow of Atlantic deep water during the Last Glacial Maximum : Nature : Nature Publishing Group
The meridional overturning circulation (MOC) of the Atlantic Ocean is considered to be one of the most important components of the climate system. This is because its warm surface currents, such as the Gulf Stream, redistribute huge amounts of energy from tropical to high latitudes and influence regional weather and climate patterns, whereas its lower limb ventilates the deep ocean and affects the storage of carbon in the abyss, away from the atmosphere. Despite its significance for future climate, the operation of the MOC under contrasting climates of the past remains controversial. Nutrient-based proxies1, 2 and recent model simulations3 indicate that during the Last Glacial Maximum the convective activity in the North Atlantic Ocean was much weaker than at present. In contrast, rate-sensitive radiogenic 231Pa/230Th isotope ratios from the North Atlantic have been interpreted to indicate only minor changes in MOC strength4, 5, 6. Here we show that the basin-scale abyssal circulation of the Atlantic Ocean was probably reversed during the Last Glacial Maximum and was dominated by northward water flow from the Southern Ocean. These conclusions are based on new high-resolution data from the South Atlantic Ocean that establish the basin-scale north to south gradient in 231Pa/230Th, and thus the direction of the deep ocean circulation. Our findings are consistent with nutrient-based proxies and argue that further analysis of 231Pa/230Th outside the North Atlantic basin will enhance our understanding of past ocean circulation, provided that spatial gradients are carefully considered. This broader perspective suggests that the modern pattern of the Atlantic MOC--with a prominent southerly flow of deep waters originating in the North Atlantic--arose only during the Holocene epoch.

In plain English, this appears to state that the North Atlantic Drift or Gulf Stream were reversed during the last Ice age with the surface water flowing North South and the deep sea water flowing South North.  So rather than distributing warm tropical water towards Europe, it was distributing cold Arctic water towards Europe - similar to current southerly currents off Newfoundland. It is easy to sea why this may have caused/contributed to the ice age, but what caused the reversal?

Index of Frank's Diaries

by Frank Schnittger (mail Frankschnittger at hot male dotty communists) on Wed Dec 8th, 2010 at 01:03:09 PM EST
What could explain the unusually early cold and snowy winter on the US East Coast last year and the apparent beginning of a similar one this year? Winters in recent years were mostly balmy and typically one could always expect the first measurable snow fall on or after the first week of January. Last year we had two feet in mid-December.  

We had to buy comforters this past January upon arrival in tropical Mexico where houses typically don't have heating systems. Temperatures there remained cool for several weeks and were the lowest I can recall over the past forty years. This coming winter appears to be heading in the same direction. Temps on the Yucatan peninsula will be down in the 12-13C tomorrow night. That's pretty cold when everyone there was accustomed to 42+ Celsius this past summer and there were still 32+C readings a week or two ago.


I can swear there ain't no heaven but I pray there ain't no hell. _ Blood Sweat & Tears

by Gringo (stargazing camel at aoldotcom) on Thu Dec 9th, 2010 at 01:03:05 AM EST
My own general sense of this is that colder winters in the US, especially east of the Rockies, might be associated with the documented melting of the permafrost in the Arctic, the line for which has moved south significantly over the last couple of decades. Crudely put, permafrost melts in the warmer arctic summers and much colder air moves to mid-latitudes on the surface earlier in the winter, facilitating, perhaps, warmer arctic winters. This would provide a positive feedback loop for arctic warming.

As the Dutch said while fighting the Spanish: "It is not necessary to have hope in order to persevere."
by ARGeezer (ARGeezer a in a circle eurotrib daught com) on Thu Dec 9th, 2010 at 12:29:41 PM EST
[ Parent ]
I am prepared to believe the Gulf Stream is (gradually) shutting down, though there seem to be other possible explanations.  

For for thing, if the warm water is not going to Europe, more of it might be ending up here, which would make perfect sense.  

Last year 2009-10 was a cold winter for the US as well as for Europe, BUT ONLY IN THE NORMALLY WARM SOUTHERN STATES.  In New England normal winter (that is freezing cold) weather arrived fully one month late, and ended fully one month early.  In my book that counts as a WARM winter.  

This year 2010-11 same thing, so far.  Following an astonishingly hot summer (summer of 2009 was cool and wet) again winter has been fully a month late in arriving.  

What happens next?  I don't know, but another early spring would be no surprise.  

The Fates are kind.

by Gaianne on Thu Dec 9th, 2010 at 02:46:55 AM EST
Frank, you've written an impeccable introduction to the subject, and I laud you for it. I actually may copy bits of it, if I get the chance. :)

As for the hesitation if there is a consensus on the thermohaline circulation shutting down: the current consensus is that there is no such thing as a weakening in the thermohaline circulation.

And I'm in a bit of a hurry, so here goes:

  1. the method Bryden used is simply unable to make announcements of a 30% decline, as shown in a Nature publication here;
  2. the first results of the RAPID programme which uses continuous monitoring (unlike Bryden) shows that the variability in the MOC is so large that it invalidates the work of Byrden entirely (and note that Bryden is a co-author), publication abstract here;
  3. I tried to convey that latter message in this diary;
  4. A recent NASA study with different methodologies confirms there is no detected weakening of the conveyor belt, see press release here.

Furthermore, climate models infer, with current projected temperature increases, only an actual slowdown around 2100. And lastly,

RealClimate: Atlantic circulation change summary

Everyone quoted is however agreed on one thing: "the notion that [a future change in the themohaline circulation] may trigger a mini ice age is a myth". The evidence of previous changes for instance at the Younger Dryas or during the 8.2 kyr event is quite strong, and significant coolings were observed particular around the North Atlantic, but even such localised coolings are not predicted to occur if the circulation slows as an effect of global warming.

by Nomad on Thu Dec 9th, 2010 at 06:05:05 AM EST
eurogreen:
The NAO is the dominant mode of atmospheric variability in the north Atlantic throughout the year and particularly prominent in the winter.
Nomad, when people talk about "dominant mode of variability" in this context, is it much more than a statistically derived principal component of the system? In other words, is it just descriptive or is there a real understanding of its dynamics and role?

Of all the ways of organizing banking, the worst is the one we have today — Mervyn King, 25 October 2010
by Migeru (migeru at eurotrib dot com) on Thu Dec 9th, 2010 at 06:17:36 AM EST
[ Parent ]
Hard for me to say - NAO is largely a meteorological phenomenon, which is not my strongest suit. It isn't even sure, I believe, whether the NAO has a coupling effect on oceanic currents. And experts still seem to quibble how to exactly measure it, or define it. So I'm not even sure if it can fully cover "descriptive", as the NAO may include traits that haven't been properly associated to it...

However, if I were to wager, I'd say that the science on NAO is somewhere halfway between describing it and mapping out the dynamics involved.

Does that help?

by Nomad on Thu Dec 9th, 2010 at 07:06:03 PM EST
[ Parent ]
I just remember a turbulence workshop where some people presented a Principal Orthogonal Decomposition of atmospheric data and waxed lyrical about it. "POD modes" are a great way to reduce the hell that is fluid dynamics to a finite-dimensional system of equations, but if you impose the POD modes you obtain for describing past history onto a model to try to predict future behaviour you cannot predict deviations from past history...

Of all the ways of organizing banking, the worst is the one we have today — Mervyn King, 25 October 2010
by Migeru (migeru at eurotrib dot com) on Fri Dec 10th, 2010 at 04:11:45 AM EST
[ Parent ]
In layman's terms - if you try to predict the future based on (complex equations derived from) the past, all you can do is extrapolate the past, not predict new or deviations from past trends?  

But can you not factor in new data - e.g. increased CO2 levels - leading to significantly different results?

Index of Frank's Diaries

by Frank Schnittger (mail Frankschnittger at hot male dotty communists) on Fri Dec 10th, 2010 at 05:09:57 AM EST
[ Parent ]
You can find different amplitudes, speeds, or signs of the oscillations, but if you write something like the NAO into your coordinates you may be unable to see the NAO being replaced by a substantively different pattern of variability.

The problem with dimension reduction (otherwise a very useful technique) is precisely that.

Of all the ways of organizing banking, the worst is the one we have today — Mervyn King, 25 October 2010

by Migeru (migeru at eurotrib dot com) on Fri Dec 10th, 2010 at 05:16:50 AM EST
[ Parent ]
Oops. I hadn't realised this had been discussed on ET before - my time anyway.  The reason I write on topics I don't know much about is that it brings experts like you out of the woodwork who can tell us where things are truly at.  It appears, from your comment, that the Wiki articles I quoted are a bit one-sided and need to be updated, although I deliberately kept my presentation as simple as possible for a general audience to present a hypothesis and am happy to see it rebutted.

Everywhere you go - Malawi, Kwazulu Natal, Ireland - and from the comments, the USA - people are reporting unusual weather patterns - delayed rainy seasons, droughts, excessive rainy seasons, severe winters etc. all of which could be attributed to random variation, but which people and media, being people, are seeking to find rational explanations for, with Climate Change becoming the catch-all bucket explanation when it may have no relevance or at least no provable relevance.

It seems to this non-scientific observer that there is still too great a gulf between global climate models and local weather patterns to enable meaningful connections (explanations/predictions) to be made, although that won't stop people from trying.  People don't like random - hence there has to be a God/cause.

P.S. In your earlier diary you refer to surface currents being wind driven and deep water currents being driven by thermohaline forces. However if both are part of the same interconnected system must there not also be a (reverse) thermohaline component to surface currents to keep overall salt levels within the system in balance? I.e. effectively there is (water borne) salt circulation system at all levels of the system?

Index of Frank's Diaries

by Frank Schnittger (mail Frankschnittger at hot male dotty communists) on Thu Dec 9th, 2010 at 09:25:08 AM EST
[ Parent ]
Frank Schnittger:
In your earlier diary you refer to surface currents being wind driven and deep water currents being driven by thermohaline forces. However if both are part of the same interconnected system must there not also be a (reverse) thermohaline component to surface currents to keep overall salt levels within the system in balance? I.e. effectively there is (water borne) salt circulation system at all levels of the system?
The answer is in the caption to the picture you lifted from Wikipedia for the diary body.

Wikipedia: Thermohaline Circulation


Blue paths represent deep-water currents, while red paths represent surface currents
You can see there are at least five points on the globe where the "grat ocean conveyor" current turns from surface to deep water or vice-versa.

Of all the ways of organizing banking, the worst is the one we have today — Mervyn King, 25 October 2010
by Migeru (migeru at eurotrib dot com) on Thu Dec 9th, 2010 at 10:27:37 AM EST
[ Parent ]
My query was whether haline forcing (due to increased water density caused by evaporation) was one of the engines driving surface currents as well as deepwater ones..

Index of Frank's Diaries
by Frank Schnittger (mail Frankschnittger at hot male dotty communists) on Thu Dec 9th, 2010 at 11:42:09 AM EST
[ Parent ]
I have updated the diary to reflect your more recent evidence and conclusions. Damn.  You've spoiled a good story.  However we must be responsible and not confuse the ET masses!

Index of Frank's Diaries
by Frank Schnittger (mail Frankschnittger at hot male dotty communists) on Thu Dec 9th, 2010 at 10:06:38 AM EST
[ Parent ]
I have no trouble understanding that a tiny event can cause a great change.

Say you're standing next to someone, and a cop is swinging a water cannon in your direction. You shout "Hey, Pig!" and the sound of your voice causes him to twitch the hose in your direction.

I've also worked with fluid amplifiers, which work just like transistor amplifiers. Eerily similar.

BUT, you can't back-predict, because you don't know enough. All we really know is that change is increasing, which is a bad sign. We're delicate creatures, balanced on the hope of good growing seasons, and the return of the salmon...

Align culture with our nature.

by ormondotvos (ormond no spam lmi net no spam) on Sat Dec 11th, 2010 at 03:14:27 AM EST
[ Parent ]
As I understand it catastrophe and chaos theories in maths are all about modelling "unstable" systems where small changes can give rise to dramatic and otherwise counter-intuitive consequences - the mathematical equivalent of walking off the edge of a cliff you didn't realise was there.

The problem is that predicting climate changes - particularly as they apply to particular regions requires such a monstrous amount of data - which we currently are only beginning to gather - that the degree of uncertainty around such climate models is huge.

However, as you say, human societies, and particularly those in NW Europe, are highly optimised to particular climatic patterns and any significant changes are therefore almost always problematic - e.g. rising sea levels, extreme weather events, droughts, harvest failures etc..

It seems to me that human adaptation becomes problematic and expensive at those extremes - e.g. persistent temperatures outside the 0-40 centigrade range, wind velocities above storm force, precipitation levels much above/below the long/short term average.

Global climate change thus poses huge adaptation challenges for societies as well as for the biosphere, where a further increase is mass extinction events can be expected.

Index of Frank's Diaries

by Frank Schnittger (mail Frankschnittger at hot male dotty communists) on Sat Dec 11th, 2010 at 07:46:20 AM EST
[ Parent ]
ormondotvos:
All we really know is that change is increasing, which is a bad sign. We're delicate creatures,

yes we are, sometimes too much so, spoiled and pampered by the gimme lifestyle.

supposing peoples' thoughts have power, how many people suffering have been aching and praying for change for so long?

we are comfortable, for some it has taken years of careful choices to become so, and yes we want things to stay as stable as possible, natch.

but for the vast majority of humans on earth right now, i'd venture a guess that they are fed up to the molars with the status quo, and are entreating every deity imaginable to end their pain, and, most importantly, can't afford the compassion to care very much what has to come tumbling down in our cosy world, if it holds any promise of things changing on the ground for them... that's not envying our freedoms, except the one that lets us continue to look away from the problem, and even if we grok it, we can't help be conditioned by our own survival fears, and worry that social justice/equality might take what we have gathered and have it swept away in a flood of change.

that's why it's hard not to be pessimistic, seeing the lack of action on climate change, the continued bad banking practices left unchecked, etc etc.

the ignorance of a few is holding back the betterment of many, and the fact that some of us have carved little niches of relative health in a fundamentally sick host system is entirely moot, unless we find a model of living that allows for scaling up, maybe not to infinity, lol, but a hell of a way more so than the ones most westerners model, and which the new bric richsters are falling over themselves aping and even parodying in their rabid envy and lust for the rotten apple of consumerschlockism, premature planned obsolescence, and fashionista-ism.

i say this not to counter what you have said, but to riff further on it...

"We can all be prosperous but we can't all be rich." Ian Welsh

by melo (melometa4(at)gmail.com) on Sat Dec 11th, 2010 at 10:55:33 AM EST
[ Parent ]
by Frank Schnittger (mail Frankschnittger at hot male dotty communists) on Thu Dec 9th, 2010 at 05:03:33 PM EST
must be wondering why they ever bothered to leave Greenland



Index of Frank's Diaries

by Frank Schnittger (mail Frankschnittger at hot male dotty communists) on Thu Dec 9th, 2010 at 05:12:59 PM EST
heading south...



Index of Frank's Diaries

by Frank Schnittger (mail Frankschnittger at hot male dotty communists) on Thu Dec 9th, 2010 at 05:15:45 PM EST
Removing the snow from a solar thermal collector requires a long pole with a snow rake on the end and 10 minutes work in each morning.  What's the EROI of that?

Or you can mount your collector on the south facing wall  and get greater collection due to a better angle and reflected light from the snow.

If Gary hadn't actually done it (http://builditsolar.com/) I might be dubious, but he has demonstrated straightforward, DIY implementable solutions that work just fine in Montana.

by njh on Thu Dec 16th, 2010 at 06:17:03 PM EST


Display:
Go to: [ European Tribune Homepage : Top of page : Top of comments ]