Climate Science

[Gray-Wolf]

You are a naughty one Sparticle!!! as for the 'lost' energy ? did we not just find a goodly amount of it in the 100 to 200m Ocean depths?

EDIT: Count me in on the 'Loons' camp too please!!!

Edited October 17, 2011 by Gray-Wolf

[VillagePlank]

Yes, we did; but I could never prove that that made up the difference; it was child's play to prove that the pycnocline 'trapped' (more than) the excess, but I had problems showing that emissivity between layers took time because of the differences in density - which is a little different from thinking of the ocean as a slower mode of transport for heat (which was the original hypothesis)

I did once find some law (regarding atrophy of emissivity between different densities) that seemed to describe it (ie it explained why the heat in the pycnolcine takes longer than you'd expect to escape - think of the other layers around the pycnocline as blankets) but have long since lost all my files and can't for the life of me remember what it was or where I found it.

I found the chart from another NW thread - oh, and it wasn't Kirchoffs law.

EDIT; using Rayleigh number rings a bell from the dim distant past ... if I recall correctly, the sums didn't quite add up- so the initial results seemed to be the product of overfit which is a shame because I used all the normal techniques to avoid such a basic error.

EDIT2: incidentally, the changes to pycnocline above certain latitudes - and therefore heat content escaping faster - was also a theory associated with arctic ice loss but at the time, antartica was gaining ice (even though it was fracturing faster) We also worked on a causal mechanism for ENSO along the same lines given that the warmer (or cooler) waters cluster around the equater, densities also made absorption a problem (ie the pycnocline acted like a mirror) until a certain threshold was reached where it got overloaded and 'over' heated the layer underneath.

EDIT3: Of course, all conjecture - I could never prove a thing. So close, yet so, so, so far away ....

Edited October 17, 2011 by Sparticle

[Gray-Wolf]

Thanks ( really) for trawling back through that Sparticle!

I'll have a muse and trawl around myself to see if I can find 'numbers' around that might prove helpful in this ?(if I ever get the time to that is!!)

[jethro]

Tbh PP, all most people have ever said (there are some loons, I admit) is that the Sun is not the sole contributor to our climate...If it was - we'd all be frozen solid?

But that's not quite right though Pete and to be honest, that's just a cover-all, get out clause.

When it comes to climate and more importantly, recent climate, the argument has been that only TSI is relevant, that it is the only thing which varies which can have any impact upon short term climate and that the changes in recent decades cannot account for change in climate. The new research shows that the (regarded to be) sceptical side of this debate were right to insist that only measuring TSI alone is not enough.

[Methuselah]

But that's not quite right though Pete and to be honest, that's just a cover-all, get out clause.

When it comes to climate and more importantly, recent climate, the argument has been that only TSI is relevant, that it is the only thing which varies which can have any impact upon short term climate and that the changes in recent decades cannot account for change in climate. The new research shows that the (regarded to be) sceptical side of this debate were right to insist that only measuring TSI alone is not enough.

Good point, J...We are learning all the time. But, whatever, GHG's (and the biosphere) and their 'balance' with Solar input and re-radiation, are what maintain the Earth's 'heat balance'. But, there's nowt we can do to alter Solar output...

[knocker]

I don't know whether this has been posted before. It's a paper from last year. It's quite long and detailed so can't make any observations as haven't had a chance to read properly but at first glance looks quite interesting. Just a quick extract from .

6.4. Climate Change

[164] Finally, the role of solar variability in climate change has received much public attention because reliable estimates of solar influence are needed to limit uncertainty in the importance of human activity as a potential explanation for global warming. Extensive climate model studies have indicated that the models can only reproduce the late twentieth century warming when anthropogenic forcing is included, in addition to the solar and volcanic forcings [iPCC, 2007]. The change in solar radiative forcing since 1750 was estimated in the IPCC [2007] report to be 0.12 W m−2, corresponding to an increase in TSI of 0.69 W m−2. A value of 0.24 W m−2 solar radiative forcing difference from Maunder Minimum to the present is currently considered to be more appropriate. Despite these uncertainties in solar radiative forcing, they are nevertheless much smaller than the estimated radiative forcing due to anthropogenic changes, and the predicted SCâ€related surface temperature change is small relative to anthropogenic

Solar Influences on Climate.

http://www.agu.org/j...009RG000282.pdf

Edited October 22, 2011 by weather ship

[Cloudman]

Amazing....... Suddenly all these people are claiming that the sun does indeed have an effect on climate. It wasn't that long ago when this was denied by many proponents of AGW theory. Heaven forbid that the rule book has changed.

What an amazing comment, how do you think natural climate change over geological time is explained in paleoclimatology ? The influence of UV on atmospheric circulation has been known since Jo Haigh's paper in 1995. Are you aware if Shindell's paper from 2001 using a GCM to simulate the little ice age attributing it to increased northern blocking over Europe associated with a long term drop in UV

[Cloudman]

I don't know whether this has been posted before. It's a paper from last year. It's quite long and detailed so can't make any observations as haven't had a chance to read properly but at first glance looks quite interesting. Just a quick extract from .

6.4. Climate Change

[164] Finally, the role of solar variability in climate change has received much public attention because reliable estimates of solar influence are needed to limit uncertainty in the importance of human activity as a potential explanation for global warming. Extensive climate model studies have indicated that the models can only reproduce the late twentieth century warming when anthropogenic forcing is included, in addition to the solar and volcanic forcings [iPCC, 2007]. The change in solar radiative forcing since 1750 was estimated in the IPCC [2007] report to be 0.12 W m−2, corresponding to an increase in TSI of 0.69 W m−2. A value of 0.24 W m−2 solar radiative forcing difference from Maunder Minimum to the present is currently considered to be more appropriate. Despite these uncertainties in solar radiative forcing, they are nevertheless much smaller than the estimated radiative forcing due to anthropogenic changes, and the predicted SCâ€related surface temperature change is small relative to anthropogenic

Solar Influences on Climate.

http://www.agu.org/j...009RG000282.pdf

That does go to the heart of the matter, changes in solar output over these timescales only have quite small impacts on global temperature relative to greenhouse gas forcing but the larger changes in UV do have an impact on atmospheric circulation and hence regional weather but not global temperature.

[Village]

That doesnt follow

That does go to the heart of the matter, changes in solar output over these timescales only have quite small impacts on global temperature relative to greenhouse gas forcing but the larger changes in UV do have an impact on atmospheric circulation and hence regional weather but not global temperature.

I dont think that follows personally. If regional weather eversoslightly changes as it does all of the time this does have an impact on global temperatures. One rarely has regional variability without a change in temperature and therefore global temperatures. This also follows with regards to precipitational variability because the process of varying humidity also alters atmospheric energy and surface temperatures most particularly nocturnally.

[Methuselah]

That doesnt follow

I dont think that follows personally. If regional weather eversoslightly changes as it does all of the time this does have an impact on global temperatures. One rarely has regional variability without a change in temperature and therefore global temperatures. This also follows with regards to precipitational variability because the process of varying humidity also alters atmospheric energy and surface temperatures most particularly nocturnally.

Unless of course, said local changes are essentially random. In which case the increases at some locations might be more-or-less offset by decreases at others

[Thundery wintry showers]

I have heard several times that global warming and the climate trends these last few years would for us in northern Europe result in

1) hotter, drier summer summers

2) wetter winters

I remember seeing projections like this, though most of them added the caveat "hotter, drier, but not necessarily sunnier, summers"- that last caveat perhaps suggests a shift towards more of those "Azores High ridging into the south" type setups which are less reliable sunshine wise than a breakaway anticyclone sat on top of the country or out in the North Sea.

I've followed quite a lot of research in this area and while there is a consistent signal for a rise in temperature associated with increased greenhouse gas concentrations, the signals for rainfall are very mixed. There is a suggestion of greater rainfall variability, and tentative suggestions of wetter winters and drier summers, but most climate scientists only place high confidence on the "greater variability" signal.

UK rainfall showed a marked trend towards the generally-projected outcomes during the 1980s and 1990s with wetter winters and drier summers but this trend has switched during the 2000s, again highlighting the uncertainty over rainfall changes.

[Andy_]

U.N. Climate Conference: Geoengineering Could Save Earth -- Or Destroy It

A report released late Thursday in London and discussed Friday at the U.N. climate conference in South Africa said that – in theory – reflecting a small amount of sunlight back into space before it strike's the Earth's surface would have an immediate and dramatic effect.

Within a few years, global temperatures would return to levels of 250 years ago, before the industrial revolution began dumping carbon dioxide into the air, trapping heat and causing temperatures to rise.

But no one knows what the side effects would be.

They could be physical – unintentionally changing weather patterns and rainfall. Even more difficult, it could be political – spurring conflict among nations unable to agree on how such intervention, or geoengineering, will be controlled.

The idea of solar radiation management "has the potential to be either very useful or very harmful," said the study led by Britain's Royal Society, the Washington-based Environmental Defense Fund and TWAS, the academy of sciences for the developing world based in Trieste, Italy.

http://www.huffingtonpost.com/2011/12/02/geoengineering-un-climate-conference_n_1125240.html?ncid=edlinkusaolp00000003

Wouldn't reflecting sun back from Earth mimic the effect of Low Solar Activity or a 'Maunder Minimum', possibly sending Europe and North America into a very cold state, and see us reliving some of the Winters 1600's?

[pottyprof]

this trend has switched during the 2000s, again highlighting the uncertainty over rainfall changes.

Which in turn should raise uncertainty in regards to climate predictions as a whole. The things we thought were sorted are now questionable. Why is it not playing ball? What else now becomes questionable because rain isn't falling in the areas we expected at the time we expected? How much effect has this had on our ability to forecast climate conditions? Must be a minefield TWS.

[Village]

It is a minefield, quite right. This also should indicate why it is that predictions keep varying.

Its obvious that the climate change theory relative to one small so called "greenhouse" gas.... (actually its nothing like a greenhouse) is not what is driving this planet. Water vapour influence is absolutely huge and makes any tiny weeny change in CO2 insignificant.

So why is everything all about CO2 and nothing else? MONEY....thats what has driven the whole theory on climate change. Its got little to do with science but a whole lot to do with money. Why else would almost every thesis or scientific paper over the past decade always maintain a link to climate change? Why? not because everything is linked but because thats how you get funding for your project...no matter how diverse, how insignificant, if you link it to CO2 theoretics you get the cash funding.

The whole thing is perverse and its the sole reason why we have had scientific report after report after scientific paper after paper on absolutely everything and climate change. We are on overload now and people have started to turn off.

Edited December 5, 2011 by Village

[laserguy]

The whole thing is perverse and its the sole reason why we have had scientific report after report after scientific paper after paper on absolutely everything and climate change. We are on overload now and people have started to turn off.

I turned off a few years back,but it's fun to tune in every now and again to watch the circus.

[Gray-Wolf]

Many of the responses are cripplingly slow (to begin with?) as mother N. has a wish to remain 'in the grove' that it has occupied for a long while. Of course once the 'forcings' have been applied for long enough sections of our 'stable' climate will start to give way (as we see in the Arctic) and these failures will start to 'speed' the process of climate variability along (as we see with sea ice loss impacting submerged Methane Hydrate/permafrosts) leading to a more dynamic system that will have the population again focused on the issues we have courted for ourselves.

[jethro]

Many of the responses are cripplingly slow (to begin with?) as mother N. has a wish to remain 'in the grove' that it has occupied for a long while. Of course once the 'forcings' have been applied for long enough sections of our 'stable' climate will start to give way (as we see in the Arctic) and these failures will start to 'speed' the process of climate variability along (as we see with sea ice loss impacting submerged Methane Hydrate/permafrosts) leading to a more dynamic system that will have the population again focused on the issues we have courted for ourselves.

I get your point GW but I do think there's an enormous hole in your above take on the subject.

Mankind's belief that climate is stable is an utter fallacy - there's no such thing as static or stable, there is only ever change. What you term as a failure in the climate system isn't a failure at all, it's a system in perfect working order, doing exactly what it should do.

[songster]

I get your point GW but I do think there's an enormous hole in your above take on the subject.

Mankind's belief that climate is stable is an utter fallacy - there's no such thing as static or stable, there is only ever change. What you term as a failure in the climate system isn't a failure at all, it's a system in perfect working order, doing exactly what it should do.

I sort of agree, except that the teleological phrasing is unfortunate. Yes, there is only change. Yes, the late Holocene climate to date has been almost unprecedentedly stable. Yes, Nature is "working" in that you have a system that is transporting excess heat to the poles and gradually dumping it into the "heat sink" of the ice caps. Yes, this is all "natural" in the sense that much wider climate swings have happened before, and life has continued to flourish - the only difference is that this time round a substantial (though debated) proportion of the warming is due to fossil fuel emissions. Yes, the world and its coastlines would look little different from a global perspective even if substantial parts of both ice caps melted, as they are predicted to do if we keep on as we are.

However, our civilisation is strongly adapted to the present stable climate. Most of our population centres are on coasts. Almost all our food crops are suited to very narrow temperature bands. Neither they nor we would survive long "au naturel". Earth may be tolerant of rapid climate change: we are not, so we really <i>really</i> shouldn't be poking things with sticks to see what happens. Unfortunately our continued carbon emissions are just that - a large-scale, reckless, unknown and uncontrolled experiment on the global climate.

Edited December 5, 2011 by songster

[Gray-Wolf]

That is the point exactly Songster. We (global population) are very dependant upon the narrow climate band that has persisted for the past few thousand years. We now see atmospheric methane levels not seen in over 40,000yrs (so we are told?) so we have 'built' ourselves (and continue to build?) an atmosphere of a composition never seen during our 'stable climate' phase (I believe J's just being pedantic about the 'change' thing and ,if not, needs to pull back a few stops to see climate over a longer period to 'see' how stable we have been since Agriculture first flourished?).

Build the atmosphere and surely climate will follow to suit that 'composition'. If less than 600ppm of CO2 is the threshold to build ice sheets then surely ,over time, over 600ppm CO2 will see the sheets disappear?

How the climate manages the transition between states is what should fill our imaginings not whether it will occur. It would be like looking at a dish of water when you suddenly drop the room temp to minus 2c. You know it will freeze but when and how? that's the interesting point.

I'm constantly billed as a 'Doomsayer' but what if there is to be a fair amount of doom to come?

We now know that one of the climate forcings that was left out of the last climate model predictions is not only 'real' but also looks to be a far bigger player than we understood back in the late 90's/early noughties. If we now know we have missed our 2c target for warming then we know we are in very dodgy times with the possibility/probability of rapid climate shift as 'natural' GHG sources and sink failures do as they have always done and force rapid warming. It's just that this time we have given a bit of a 'leg up' with our addition of deep stored carbon that should not have entered the carbon cycle.

[jethro]

I sort of agree, except that the teleological phrasing is unfortunate. Yes, there is only change. Yes, the late Holocene climate to date has been almost unprecedentedly stable. Yes, Nature is "working" in that you have a system that is transporting excess heat to the poles and gradually dumping it into the "heat sink" of the ice caps. Yes, this is all "natural" in the sense that much wider climate swings have happened before, and life has continued to flourish - the only difference is that this time round a substantial (though debated) proportion of the warming is due to fossil fuel emissions. Yes, the world and its coastlines would look little different from a global perspective even if substantial parts of both ice caps melted, as they are predicted to do if we keep on as we are.

However, our civilisation is strongly adapted to the present stable climate. Most of our population centres are on coasts. Almost all our food crops are suited to very narrow temperature bands. Neither they nor we would survive long "au naturel". Earth may be tolerant of rapid climate change: we are not, so we really <i>really</i> shouldn't be poking things with sticks to see what happens. Unfortunately our continued carbon emissions are just that - a large-scale, reckless, unknown and uncontrolled experiment on the global climate.

Food crops are not suited to very narrow temperature bands, there is a huge temperature range in which food crops grow. Peer reviewed studies, including projections from the IPCC show and predict a rise in global crop production. There will be some losses and some gains, the increase is not predicted to be across all staple crops - with the current available strains of crops like Wheat, much work is already being done to breed in drought resistance and increase yields.

'Despite these dramatic predictions for rising global temperatures and extreme temperature events, the latest IPCC assessment report predicts that adaptation of agriculture will result in increased yields of cereal crops (maize [Zea mays], wheat [Triticum spp.], and rice [Oryza sativa]) in mid- to high-latitude regions with modest increases in temperature across a range of CO₂ concentrations and precipitation changes (Easterling et al., 2007). With warming temperatures of 1°C to 3°C, yields at lower latitudes are predicted to decrease, although global food production is predicted to increase (Easterling et al., 2007). '

http://www.plantphys.../154/2/526.full

Poking with a large stick........ It's actually quite a small stick, if you look at natural variation in CO2, the teeny percentage of the atmosphere that is CO2 and the even teenier part of that which is our contribution and it's not really a stick at all, more like the tip of a twig (at most).

Reckless, unknown and uncontrolled experiment.......wanting to know and be in control are human traits. Not knowing or being in control isn't reckless, it's merely a fact of life when it comes to climate. With or without CO2 we still wouldn't know what the future held or be able to control it - the closest we get is being able to say one day there will be another ice age, no one knows when, no one can stop it happening.

Why are people so afraid of a future they cannot know or predict?

GW - when is this 2c supposed to happen? What target have we missed?

[songster]

Not sure why you quoted the abstract there without quoting the discussion or the conclusion.

For example:

The IPCC projections assume that yield improvements from the latter half of the 20th century will continue into the future; however, based on historical temperature-crop yield relationships, potential ceilings to crop yields, and limitations to expansion of agricultural lands, that assumption may not be sound (Long and Ort, 2010). In fact, the relative rates of yield increase for all of the major cereal crops are already declining (Fischer and Edmeades, 2010).

OK, it's not yet a decrease in absolute yield, but the human population continues to grow exponentially. If crop yield increases fail to keep up, that means less per head.

The response of maize and soybean to temperature is also nonlinear, and the decline in yields above the temperature optimum is significantly steeper than the incline below it (Schlenker and Roberts, 2009). Based on the nonlinearity of the temperature response, U.S. maize and soybean yields were predicted to decrease by 30% to 46% before the end of the century under the IPCC scenario with the slowest warming trend.

Not the dominant human crop, perhaps, but that's a very large proportion of animal feed.

There is now overwhelming evidence that “business as usual†crop development will be insufficient to adapt crops over the wide range of growing regions that will be required to meet expanding global agricultural demand. Moving crops pole-ward seems an inevitable element of the multifaceted adaptation to increasing global temperatures that must be implemented, but it would be misleading to believe that this alone can maintain yields. For example, migration of the North American Corn Belt into Canada vacates the high-quality prairie soils for the less productive soils farther north. And in many important agricultural areas of the world, pole-ward migration is not possible, such as the Wheat Belt of Australia, where an ocean lies to the south (Long and Ort, 2010)

That's the overall conclusion, and it's not exactly Panglossian.

****** edit to add ******

Poking with a large stick........ It's actually quite a small stick, if you look at natural variation in CO2, the teeny percentage of the atmosphere that is CO2 and the even teenier part of that which is our contribution and it's not really a stick at all, more like the tip of a twig (at most).

Wha? Around 40% of current CO2 levels are due to fossil fuel emissions. That's not teeny! Yes, CO2 levels have varied by more than this historically - in eras with vastly different climates, vastly different sea levels and continental configurations. That's the point. Find me any historical period with CO2 levels similar to today and a climate similar to today.

Edited December 6, 2011 by songster

[Gray-Wolf]

Makes me wonder why Russia had to cancel all of it's exports when their drought struck? Also the impact across N America /Canada from last years cold wet start?

It is ,we find, one thing to have studies and wholly another to see in the field the impacts of an increasingly extreme climate?

I feel the 'Aid agencies' most impacted by such shortfalls would take no solace from knowing that the paper exercises leaves them with nothing to fear. Likewise the drought stricken areas of Africa, currently undergoing desertification ,can relax sure in the knowledge that their crops are far hardier/better able to cope with such extremes than would appear in reality?

I'm not really sold on your attempts to comfort/console J'? My pocket tells me recent grain shortages have a real impact in the real world and I can only see climatic issues at the root of such shortfalls.

Humanity has a great deal of work ahead if it really wishes to maintain adequate grain resources for the planet. Eventually, as in Africa now, we will see areas becoming less hospitable to grain production whilst 'new areas' open up for development. It may be in our best interests to start the development of such lands now (at least planning?) before we are forced to seek alternate regions?

[jethro]

Sorry GW and Songster, no time at the mo - knee deep in decking halls with boughs of Holly and Wreaths. I'll get back to you when life's a little less manic.

[Methuselah]

Food crops are not suited to very narrow temperature bands, there is a huge temperature range in which food crops grow. Peer reviewed studies, including projections from the IPCC show and predict a rise in global crop production. There will be some losses and some gains, the increase is not predicted to be across all staple crops - with the current available strains of crops like Wheat, much work is already being done to breed in drought resistance and increase yields.

'Despite these dramatic predictions for rising global temperatures and extreme temperature events, the latest IPCC assessment report predicts that adaptation of agriculture will result in increased yields of cereal crops (maize [Zea mays], wheat [Triticum spp.], and rice [Oryza sativa]) in mid- to high-latitude regions with modest increases in temperature across a range of CO₂ concentrations and precipitation changes (Easterling et al., 2007). With warming temperatures of 1°C to 3°C, yields at lower latitudes are predicted to decrease, although global food production is predicted to increase (Easterling et al., 2007). '

http://www.plantphys.../154/2/526.full

Poking with a large stick........ It's actually quite a small stick, if you look at natural variation in CO2, the teeny percentage of the atmosphere that is CO2 and the even teenier part of that which is our contribution and it's not really a stick at all, more like the tip of a twig (at most).

Reckless, unknown and uncontrolled experiment.......wanting to know and be in control are human traits. Not knowing or being in control isn't reckless, it's merely a fact of life when it comes to climate. With or without CO2 we still wouldn't know what the future held or be able to control it - the closest we get is being able to say one day there will be another ice age, no one knows when, no one can stop it happening.

Why are people so afraid of a future they cannot know or predict?

GW - when is this 2c supposed to happen? What target have we missed?

Most of what you say is there is fair enough, J. But, 40% of what's actually there (atmospheric CO₂) being down directly to us cannot really be described as 'teeny' now, can it? :smilz38:

[VillagePlank]

Several recent studies have highlighted the possibility

that the oceans and terrestrial ecosystems have started

loosing part of their ability to sequester a large proportion of

the anthropogenic CO2 emissions. This is an important

claim, because so far only about 40% of those emissions

have stayed in the atmosphere, which has prevented

additional climate change. This study re-examines the

available atmospheric CO2 and emissions data including

their uncertainties. It is shown that with those uncertainties,

the trend in the airborne fraction since 1850 has been 0.7 ±

1.4% per decade, i.e. close to and not significantly different

from zero. The analysis further shows that the statistical

model of a constant airborne fraction agrees best with the

available data if emissions from land use change are scaled

down to 82% or less of their original estimates. Despite the

predictions of coupled climate-carbon cycle models, no trend

in the airborne fraction can be found.

Citation: Knorr, W.

(2009), Is the airborne fraction of anthropogenic CO2 emissions

increasing?, Geophys. Res. Lett., 36, L21710, doi:10.1029/

2009GL040613.

Here (PDF)