Bob Tisdale writes:
NINO3.4 SST Anomalies Make A Surge
NINO3.4 SST Anomalies have reached 1.5 deg C for the week centered on October 28, 2009.
http://i37.tinypic.com/nzoyvn.png
NINO3.4 SST AnomaliesSOURCEOI.v2 SST data is available through the NOAA NOMADS website:
http://nomad3.ncep.noaa.gov/cgi-bin/pdisp_sst.sh?lite
Here’s a look at the current global SST map:
tallbloke (11:37:03) :
“The point was that the Milankovich variations are huge compared to solar activity variations.”
Oh I don’t know about that,
Apparently not. Since the energy in the solar wind is a million times smaller than that in TSI, the heliospheric magnetic field doesn’t matter compared to the very large [in W/m2] variations of the insolation.
Leif Svalgaard (11:06:08) :
The point was that the Milankovich variations are huge compared to solar activity variations.
No, they are not.
They are at 65N or 75N but not for the planet as a whole. I was using the global annual solar irradiance which only varies by +/- 2 watts/metre^2 over 100,000 year cycle.
Bill Illis (13:04:23) :
They are at 65N or 75N but not for the planet as a whole.
Milankovich’s whole argument is that the effect takes place when there is not enough energy to melt the snow in summer [i.e. at high Northern latitudes]. It doesn’t matter what the rest of planet does.
Bill Illis (10:00:36) :
Thanks Bill, but struggling to see the orbit data on the graph, it should be a 100,000 year cycle.
tallbloke (11:37:03) :
Since the variation in TSI seems to have a terrestrial amplification factor of between 7-10 (Shaviv) This is not insubstantial either. Then there’s the variation in the UV which is large in percentage terms… Plenty of large solar variations we don’t yet know the effects or consequences of.
Yep, much more than just TSI to consider.
Leif,
You asked what happens if solar irradiance increases by 0.001% for a million years. I gave a real-world example where it does actually increase by +0.003% for 30,000 years at least. I then went on to say it hardly makes any difference – +0.2C only. I then noted that even with this 0.003% higher solar irradiance, the Earth still goes into an ice-age (because of the ice-Albedo effect).
Bill Illis (15:20:21) :
I then noted that even with this 0.003% higher solar irradiance, the Earth still goes into an ice-age (because of the ice-Albedo effect).
That is not how it works. The glaciation comes about because the Northern Hemisphere summer does not get enough heat to melt the snow during the summer, so it accumulates. The difference in insolation is large, tens of W/m2.
Geoff Sharp (15:11:20) :
Since the variation in TSI seems to have a terrestrial amplification factor of between 7-10 (Shaviv) etc
All good except that no clear solar cycle effect is seen above the 0.1K level.
Leif,
I know about the changing insolation at 65N and the summer melt issue. I have a post coming up where I will show exactly how the changing summer solar insolation at high latitudes puts us into and then takes us out of ice ages (there will be detailed calculations and I’m using the numbers at 75N instead of 65N because the glaciers have to build up at 75N before they can build up at 65N and there is no sea ice at 65N (that latitude is mostly land), the sea ice melts or doesn’t melt at 75N. Technically, without the ice-Albedo effect, the changing summer insolation at 65N or 75N doesn’t match the ice age cycles – there needs to be a large Albedo effect which even the Milankovitch Cycles can only break about a third of the time.)
I’d show a really nice chart of that now but I’m saving it.
I was just saying that solar irradiance doesn’t change enough to affect Earth’s temperatures very much, backing up your position.
Bill Illis (18:52:33) :
I was just saying that solar irradiance doesn’t change enough to affect Earth’s temperatures very much, backing up your position.
You sure have a backwards way of saying it.
Bob Tisdale (04:28:44) :
Since that paper says nothing about cosmic rays, I don’t see that it’s topical, other than background material on clouds in general.
I repeat, there is enough evidence that cosmic rays affect cloud cover significantly enough to be a/the major contributor to climate change. What the CLOUD experiments are looking for is the mechanism for a process that’s already accepted by many as highly probable.
Oh, and that reminds me. I didn’t address L.S.’s comment. “You’ll be amazed at what is spend on things that don’t pay off. Often it is worth spending money simply to see if it pays off.”
Note that he has edited it (wish I had editorial privileges) by adding a second sentence, without which the first appears a logical fallacy, but now a mere non sequitur. The fact that things we spend money on sometimes fails isn’t proof that what we are now investing in will fail. My point was that if there weren’t sufficient evidence for the phenomenon, there would be no justification to invest in investigating it The fact that they are proves that they believe that the evidence he is saying is so weak really isn’t. And that is really just what I previously said, that they think it is “worth spending money” on it, because it looks like a good bet. If it was as flimsy as L.S. claims, it’s not likely to have gotten this far, because (for the umpteenth time) money and resources are not thrown at things “just to see” what will happen. There has to be a justification, and it has to be based on evidence, not wishful thinking.
Recapping, his fist sentence is at best a non sequitur, and his second just corroborates what I have been saying.
I’ve given lots of links to substantiate my position. I will only repeat this one from CERN, where the next phase of CLOUD is currently under way (still looks promising enough to throw even more money at).
http://cdsweb.cern.ch/record/1181073?ln=ru
So, what I’m waiting for is the results of CLOUD, because it’s got a good shot at elucidating the mechanism, if they guess correctly about how to go about that. But if they don’t succeed, it still doesn’t disprove the connection between cosmic rays and climate, for which the evidence goes back throughout all geological history.
http://www.sciencebits.com/ice-ages
And for CO2, no such connection exists – not even close.
http://www.junkscience.com/images/paleocarbon.gif
Whatever the eventual mechanism – the normal solar cycle has been shown to have an effect on sea surface temperatures – the latest work I have seen is
Camp CD and Tung KK (2007) ‘Surface warming by the solar cycle as revealed by the composite mean difference projeaction’ Geophys. Res. Lett. 34 L14703 doi:10.1029/2007GL030207
Where they found 0.2 C difference from minimum to maximum and some kind of poleward amplification. ) 0.2 C is not an insignificant amount – but if solar cycles were always of the same amplitude, there would be no overall climatic effect.
Here is what I think we know relatively certain:
Whatever the mechanisms attendant on the Milankovitch cycles, they are not relevant to the later Holocene (not since the Holocene maximum 8000 years ago) –
There are long cycles of solar activity within the late Holocene that correspond to warm and cool periods – Roman Warm, Dark Age cool, Medieval Warm, Little Ice Age cool, current Modern Warm, (roughly 800 year cycle from peak to peak) and the cool periods seem to correspond to low solar magnetic activity and lower TSI (but not as low as we thought – am happy to accept Leif’s analysis). On top of this ‘wave-form’ we have oceanic oscillations in each basin – the cause of which is not known – and which seem to be driven by changes in sea level pressure and which produce alternate cold and warm phases (around 30-70 year cycles -PDO/AMO/AO). Shorter term cycles such as the NAO and ENSO also ride on these longer waves.
All of these waves seemed to have peaked in the modern warm period between 1998-2006.
Given that the longest cycle – 400 years from trough to peak – the LIA, being the last trough, produces a global range of plus or minus 0.5 C (mean), and we are not at present outside of that variability, then we should be looking for mechanisms that can explain that longer term variability (that, I understand was Svensmark’s motivation – and he was looking for the amplifier).
This amplifier does not have to be very large. For example – IF the 0.2C cycle in the oceans due to the 11 year solar cycle is related to a cooling effect at the minimum, then if that minimum were to be prolonged – as in a Dalton or more powerfully a Maunder, then I would argue, it could have a cumulative effect – i.e. the oceans would lose heat continuously until magnetic activity/TSI built up again. The mechanism could be cloud mediated – either by cosmic rays (some evidence) or UV effects on the jetstream and storm-tracks (some evidence) – or both of these in concert. It would seem logical that the oceans would cool steadily, and then warm again – as we have seen from the ‘recovery from the Little Ice Age’ argued by Prof Akasofu (Intl Arctic Rsearch Centre).
We can easily see the heating of the oceans from 1980-2000 by enhanced penetration of SW radiation – and although there is much disagreement about the exact amount and the total trend – it is present in many records – and of course in the upper ocean heat content data. The leveling of the OHC since 2003 (again disputed but at the very least a lessening of the build-up) would indicate a relatively quick response of the oceans to changing cloud conditions (and again cloud data shows a shift around 2001/2002 to less SW coming in). I think this may be correct, because 80-90% of the warming signal appears locked in the upper 300m over most of the oceans – and can only be transferred to depth at the zones of downwelling (there being little vertical mixing over most of the oceanic regions).
If we look at the spatial distribution of the upper ocean warming – it is not homogenous – the warmth is concentrated in two or three major gyres, with most of it in the northern hemisphere – and this heat store then loses heat to the land downwind – see
Compo & Sardeshmukh (2008) Oceanic Influences on Recent Continental Warming – Earth Systems Research Laboratory – NOAA, Boulder, Co.
for the signal being transferred to land (and absence of any indication of a greenhouse warming effect – other than in a warmer ocean).
I think that this long cycle – with irregular period, peaking roughly every 1000 years, and resultant ocean heat storage and loss, is adequate to explain the late Holocene variability – and MUST be solar related (sorry Leif, I think the paleo-climate data clinches it – please do read ‘Chill’).
One last line of evidence – which I review in my book, is that since 2006 – a vast store of heat has been lost from the NE Pacific off Alaska (the turning of the PDO) – and the Atlantic gyre is also losing heat. The jetstream has shifted southward (contrary to model predictions) and so have the cloud banks that insulate northern waters – and I expect also a reversal of the 14% increase of Arctic basin cloud since 1980, as well as a reduction in penetrating warm currents. IF this were to continue, then global temperatures would drop by 0.5 C, maybe more – and this could well be maintained at some kind of equilibrium for as long as solar activity remained constant. Once it ramped up again, the process would go into reverse and the oceans gain heat again.
Of course, we can expect SOME greenhouse effect from human emissions – but I don’t see how we can isolate a signal at the level of decadal variability – certainly not as claimed by attribution models for the 1950-2010 period. The modellers acknowledge that their understanding of both oceanic and solar-terrestrial climate effects is poor. They also acknowledge they cannot accurately model cloud feedbacks and that they use unproven gain-factors in their equations that could readily be nullified by cloud feedback. Thus we have TWO competing factors – natural AND GHG, both increasing at the same time.
I have made some effort to find a maximum signal for GHG – by looking at the recent Arctic warm peak compared to the previous (1940) – and I would put it at 20%. Of course, the recent peak may be riding on top of a natural modern warm period wave (I think it is) – and hence that 20% is likely to be generous.
Thus the current – 0.4 C ‘anomaly’ probably contains 0.1C GHG effect and we are only one-third the way to a doubling of GHG. Saturation effects and ‘warming in the pipeline’ complicate matters, but I think 0.3-0.5 C for a doubling is the kind of range that is compatible with the current knowledge.
That does not mean to me we can all go home and stop worrying about climate – natural climate change is dangerous to vulnerable populations – and I would like to see a huge effort to make human ecosystems resilient to natural change. Sadly, if the GHG scare is shown to be a scam (and I don’t like that word because I think a lot of scientists have genuinely worked for the good of humanity out of real concern) – then the great danger is that the rich nations will turn away from all climate change concerns, and certainly away from the need to finance adaptation.