Sea Surface Temperature makes a jump

What I don’t get is how the above NOAA SST Anomaly chart jives with their other SST anomaly products, especially in the NINO1&2 region where it doesn’t look as warm as the above map where it looks like NINO 1/2 is BLAZING HOT
Ref: http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_update/ssta_c.gif
and
http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_update/ssttlon5_c.gif

Does this mean we get a California Monsoon to wash the AGW-induced drought guilt away? 1982-3 was a really great one. 880″ of snow over Donner Summit.

The Nino is heating up now after being stuck in neutral for several months. The indicators are pointing to a moderate event now.

And the subsurface anomalies are showing a small pool of high temps, in the 5 to 6 deg C range for the pentad centered on Oct 25:
http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_update/wkxzteq.shtml

Here’s the actual link to the actual article
http://bobtisdale.blogspot.com/2009/10/preliminary-october-2009-oiv2-sst.html

I would expect this based on two things:
1. A lack of hurricanes this year
2. El Nino conditions.
But please remember that surface temperatures are related to wind speed. If the trade winds are weaker, there will higher surface temperatures.

Adam from Kansas (19:08:40) :
Adam: The link you provided was for the main page. If you’ll link the post you’re discussing, or link the graph (they’re below every illustration), I’ll be happy to reply.
Regards

So El NIno ain’t dead yet. Which is good news, the dry winters (when we are supposed to get rain / snow) were really bugging me. I hate watering.

To rbateman:
Interesting article in the Salt Lake Tribune today 11/02/09: “Scientists Find patterns in Utah’s wet-dry cycles” http://www.sltrib.com/ci_13681950?IADID=Search-www.sltrib.com-www.sltrib.com
“They looked at data going back 1000 years, discovering a powerful relationship between sea-surface temperatures in a specific area of the Pacific Ocean [IPWP ?] and rainfall and snowfall in northern Utah.”
The article goes on to describe 2 other cycles, one a 40 year cycle and another a 150 year cycle. Then,all three cycles merged in the early 80s ,82-83, to create 2 perfect snow storm seasons. In the summer of 83, we had a river running down the main street (State Street) of SLC with small wooden bridges for cars to go over the water east and west. You could hear stones the size of baseballs rolling down the concrete. The writer just couldn’t manage to spit out any opinion as to the obvious connection of these patterns and AGW not being man made.

But Arctic ice keeps freezing up and outperforming the model forcast. The jump in SST is likely related to equatorial surface wind direction and the resultant El Nino. This is not a sign that the planet is warming up. It is a sign that the natural progress of El Nino and trade winds is working quite well.
http://arctic-roos.org/forecasting-services/topaz/topaz-model-forecast

But EXCEL says the linear trend of NINO3.4 SST anomalies from January 1900 to August 2009 is fundamentally flat.
What’s the linear trend on your 1990-2009 graph?
Eyeballing, the 20 year trend looks negative.

I would be interested in what SST’s have been comparing El Nino to El Nino. Otherwise we are comparing to an average which does not exist. My hunch is that El Nino strength has peaked in 98 and is slowly decreasing. But I can’t tell for sure unless we compare apples with apples instead of apples with fruit compote.

Leif Svalgaard (18:11:03) :
We expected a bit more than Rocky VI.
Instead we got Gilligan’s Volcano.

I am interested by the question about hurricanes and SSTs. Is there a correlation? Is this one of the lesser known intersections of oceanography and meteorology?

OT: Here’s another alarmist story based on “predicted higher temperatures”.
“Climate Change will Burn Yosemite” from the “we’re not biased” BBC:
http://news.bbc.co.uk/earth/hi/earth_news/newsid_8334000/8334472.stm

yes here in New Zealand its was a very cold october. The coldest October in 64 years, with all-time record low October temperatures in many areas. Exceptionally late snowfalls. Record low October temperatures were recorded on the 4th/5th in most North Island locations, and on the 9th at many South Island sites cold October.Here in Christchurch the October monthly avg was 9.8c just 1c warmer than in August.

Bob Tisdale (19:29:05) :
Not sure about the AP’s statisticians. But EXCEL says the linear trend of NINO3.4 SST anomalies from January 1900 to August 2009 is fundamentally flat.
http://i33.tinypic.com/2ihxycn.jpg
Can’t get much flatter than that.
It does look flat but the modulation of both the high’s and low’s does look to fluctuate, tending to follow the overall temperature curve and another wave pattern I know very well. Bob are there any type of records that go back further on SST for that region. If so it would be interesting to see in the same trend continues.

The SOI has been negative for some time now. From my point this is expected. Then that I think this is a disaster for my prediction that 2009 would be colder than 2008 is another matter.
If the SOI continues to be negative I would expect this El Nino to be stronger. I hope that the SOI will turn positive soon so that 2010 will be colder than 2009 and hopefully 2008.
/Sven Hagström

Geoff Sharp (23:28:41) : You asked, “Bob are there any type of records that go back further on SST for that region. If so it would be interesting to see in the same trend continues.”
You have to keep in mind that the number of observations along the equatorial Pacific increased after the opening of the Panama Canal in 1914. There are also drops in the observations during the two World Wars. I graphed the number of readings for the Cold Tongue Index region recently, data available from JISAO. Since the CTI region (6S-6N, 180 to 90W) encompasses the NINO3.4 region (5S-5N, 170W-120W), the NINO3.4 data should drop off accordingly as one goes back in time.
CTI Observations 1845 to 1991:
http://i34.tinypic.com/in71v5.png
CTI Observations 1900 to 1950:
http://i34.tinypic.com/2ilydeg.png
CTI Observations 1845 to 1900:
http://i35.tinypic.com/wrj0p0.png
With that in mind, here’s the NINO3.4 SST anomalies starting in 1870 with a linear trend. The trend is still relatively flat, less than 0.2 deg C/Century:
http://i37.tinypic.com/4r6mh1.png
And since you were interested in the underlying variations, I’ve thrown on a 5th Order polynomial trend to highlight it. (For those ready to comment about the use of a poly trend line, I’ve added a disclaimer to the graph.)
http://i35.tinypic.com/wjz21j.png

tallbloke (00:44:25) : You wrote, “Bob, on your ‘global SST map’ Tierra del Fuego, Antarctica, Canada, Siberia, Northern Europe and Greenland have disappeared.”
I hate it when Tierra del Fuego disappears. My post included only the NINO3.4 SST anomaly graph.
Anthony: You may wish to delete the word global from the sentence “Here’s a look at the current global SST map.”

Bill Illis: Have you been keeping an eye on the Sea Surface HEIGHT anomaly maps?
http://sealevel.jpl.nasa.gov/science/jason1-quick-look/2009/images/20090917G.jpg
Here’s the archive for those SSH anomaly maps.
http://sealevel.jpl.nasa.gov/science/jason1-quick-look/archive.html
This year there’s a warm pocket in the Northeast Tropical Pacific, on a mild diagonal to the northeast. Refer to the following map. The area I’m talking about would be along the eastern portion of the Intertropical Convergence Zone (ITCZ) in this map.
http://www-gte.larc.nasa.gov/img/pemtcirc.gif
If you were to run back through the archived JPL SSH maps you’ll notice that those warm anomalies (they’re subsurface since they don’t show in the surface maps) appear to be feeding the central equatorial Pacific, fueling the El Nino. You can see the same thing happening during the 1994/95 El Nino in a JPL video that compares maps of SSH and SST. It’s kind of choppy but it’s visible here:
http://sealevel.jpl.nasa.gov/gallery/tiffs/videos/SSH-SST.mov
When the El Nino runs its course, I’m gonna try to get a copy of the daily maps from JPL to make a video.

We’ve had 5 plus years of no heat increase in the top 700 meters of the ocean. Now, along with an El Nino, we are seeing SSTs increase, as they did in 1998. In 1998, the El Nino was followed (and preceded) by several years of increased heat storage in the top 700 meters of the ocean. But in 2009, we seem to be in a negative PDO, contrary to in 1998. Several authors opine that there won’t be any temperature increases for a decade or more because of a negative PDO.
So it will be interesting to see if the El Nino and higher SSTs cause increasing heat in the top 700 meters of the ocean, or whether the negative PDO will prevent or minimize such heat gain.
Another interesting science facet of this is that for some, El Nino and the PDO are interconnected. So if we get increasing heat in the upper 700 meters of the ocean going forward, does that mean that El Nino is stronger than the PDO, and that the PDO is just an artifact of a slightly different climate regime? If it is, then the predictions of a decade or more of no temperature increases may go by the board — if the lack of temperature increases really is a product of the (assumed negative phase) PDO. But that might not be the case….the sun is in cooler mode….
This complexity is what I have to revert to letting my views on the severity (or lack thereof) of temperature effects depend on data going forward.

There are problems in interpreting SST data which is mainly satellite based … infrared remote sensing only measures the temperature of the top 0.01mm of ocean. This does not necessarily represent what is going on beneath as it can be affected by many things (e.g. evapouration, solar heating, heat loss etc.).
Jon

Hi there,
didn’t Joe d’Aleo predict this nino event would rapidly fade away? In opposition to the nino models? I think it is a sign that models coupling atmosphere and sea surfaces are not that bad after all…

OT:
Hot springs found in Norwegian Sea
The researchers were stunned when the mini-sub glided into an underwater forest featuring pinnacles from which streamed water nearly 500 degrees F and saw sea life including shrimp, sea spiders, coral and eel.
“It was like looking into a fantasy world,” said Rolf B. Pedersen, who led the international expedition. “Life that can adapt to extreme conditions can have extreme characteristics.”
http://www.upi.com/Science_News/2005/08/11/Hot-springs-found-in-Norwegian-Sea/UPI-75021123792788/

Hurricanes definitely mix deep cool waters in the Gulf of Mexico with surface waters, the larger and slower moving storms doing more mixing.
I don’t know how much that would affect SSTs for the world, but it definitely happens.

From the links to the subsurface data it looks as if the warmest anomaly is at 150m and that the great majority of the warmth is confined to the top 200m ( I had a spat with RealClimate on whether the oceans were warming significantly at depth, arguing that most of the warming was confined to the top 200m – and that upper ocean heat content data to 700m might be integrating too far down) – I would love to have a better picture of how the equatorial regions absorb and transport heat in the upper 200m and how it accumulates in gyres – I think the release of heat from these gyres is central to the pattern of warming and cooling across the globe – anyone working on this?

SSTs are affected much more by hurricanes over warm but shallow water, like the GOMEX. In places where the 26ºC water is 100 meters of more deep, even a big slow moving storm like Mitch makes little difference.
Its a weak El Niño year, the Pacific is supposed to be warm.
Its complicated. Grad students study it. I have a BS in petroleum engineering. I know what I know, and not a scintilla more.

Bob, I hope you don’t mind me dropping my report on your article. I don’t see a more relevant current posting.
October (month end averages) NSIDC (sea ice extent)
30 yrs ago
1980 Southern Hemisphere = 18.9 million sq km
1980 Northern Hemisphere = 9.5 million sq km
Total = 28.4 million sq km
Recorded Arctic min yr.
2007 Southern Hemisphere = 18.6 million sq km
2007 Northern Hemisphere = 6.8 million sq km
Total = 25.4 million sq km
Last yr.
2008 Southern Hemisphere = 18.1 million sq km
2008 Northern Hemisphere = 8.4 million sq km
Total = 26.5 million sq km
This yr.
2009 Southern Hemisphere = 18.5 million sq km
2009 Northern Hemisphere = 7.5 million sq km
Total = 26.0 million sq km
Another blogger asked me if I thought this year’s seasonal ice recovery (extent 1st month ice growth) appears sluggish or lagging? I thought the following might help answer the question:
1980 Northern Hemisphere (Oct.) = 9.5 million sq km
1980 Northern Hemisphere (Sept) = 7.8 million sq km
Delta Sept\Oct Extent = +1.7
2007 Northern Hemisphere (Oct.) = 6.8 million sq km
2007 Northern Hemisphere (Sept) = 4.3 million sq km
Delta Sept\oct Extent = +2.5
2008 Northern Hemisphere (Oct.) = 8.4 million sq km
2008 Northern Hemisphere (Sept) = 4.7 million sq km
Delta Sept\Oct Extent = +3.7
2009 Northern Hemisphere (Oct.) = 7.5 million sq km
2009 Northern Hemisphere (Sept) = 5.4 million sq km
Delta Sept\Oct Extent = +2.1
1979-2000 mean (Oct.) = 9.3 million sq km
1979-2000 mean (Sept) = 7.0 million sq km
Mean Delta Sept\Oct Extent = +2.3
So in the Arctic, the first month freeze-up ice growth (+2.1) is comparable to the mean first month growth (+2.3). Beyond this… we just have to wait and see. GK

Bob Tisdale (04:01:47) :
Have you been keeping an eye on the Sea Surface HEIGHT anomaly maps? If you were to run back through the archived JPL SSH maps you’ll notice that those warm anomalies (they’re subsurface since they don’t show in the surface maps) appear to be feeding the central equatorial Pacific, fueling the El Nino. You can see the same thing happening during the 1994/95 El Nino in a JPL video that compares maps of SSH and SST. It’s kind of choppy
I think it would be useful to compare the current situation to other similar scenarios. There is always going to be slightly different circumstances but it seems many of the moderate events look exactly the same, the big events seem to be similar etc.

The discussion about 700 meter depths is contra-indicated by experience in the Anti-submarine community. There is a “thermocline” where the surface water temperatures changes to much colder temperatures. Very seldom is the thermocline any where near as deep as 700 meters.
What is so strange, is the assumption that 700 meters is an appropriate depth to measure the above Thermocline near SST temperatures. When SST rise there is an upwelling of warm water, and a COOLING of the water of the surface as it radiates Heat to the atmosphere and space.

Let the sun shine in!

The ice-melt on the pacific side of antarctica has been sluggish. It will be interesting to see what happens if /when this melt increases.

Tallbloke is on a roll it seems.
I can find his statement of the Sun giving energy to the oceans believable, when I go outside when the summer sun is blazing, I at times feel quite a bit of warmth, I can’t really discount the energy the sun brings to everything on Earth, from your own skin to concrete to water.
Anyway, I’ll just keep watching the boxing match between Tallbloke and Lief.

tallbloke (12:05:38) :
I would also like to ask how 4C ocean tempeatures release heat to 15C air temps?
As Leif points out, radiation occurs regardless of relative temperatures

The air is radiating/conducting
the water is radiating/conducting
The air is 15C
The water is 14C
is the water going to warm or is the air going to warm?
Which direction is the energy flow?

And for those wondering about Solar Cycles versus ENSO, here’s a graph of NINO3.4 SST anomalies and scaled monthly Sunspot Numbers:
http://i33.tinypic.com/m4vty.png

Leif Svalgaard (16:47:24) :
Geoff Sharp (16:11:17) :
There are modulators of TSI, they are called clouds.
——————-
A higher temperature [because of higher TSI] means more clouds [negative feedback as Spencer points out], so the effect of a 0.1% increase of TSI might be even less than 0.1K in the long run.
You are grabbing at straws here, the greater modulation comes at minimum or low activity, more clouds from more GCR’s and less ozone. At higher levels of activity there is reduced cloud cover as well…as explained here.
“In order for such reinforcement to take place many small wheels have to interdigitate. The initial process runs from the top downwards: increased solar radiation leads to more ozone and higher temperatures in the stratosphere. “The ultraviolet radiation share varies much more strongly than the other shares in the spectrum, i.e. by five to eight per cent, and that forms more ozone” explains Katja Matthes. As a result, especially the tropical stratosphere becomes warmer, which in turn leads to changed atmospheric circulation. Thus, the interrelated typical precipitation patterns in the tropics are also displaced.
The second process takes place in the opposite way: the higher solar activity leads to more evaporation in the cloud free areas. With the trade winds the increased amounts of moisture are transported to the equator, where they lead to stronger precipitation, lower water temperatures in the East Pacific and reduced cloud formation, which in turn allows for increased evaporation. Katja Matthes: “It is this positive back coupling that strengthens the process”. With this it is possible to explain the respective measurements and observations on the Earth’s surface.”
http://wattsupwiththat.com/2009/08/27/ncar-spots-the-transistor-effect-small-solar-activity-fluctuations-amplify-to-larger-climate-influences/#more-10339

Don’t know if it is related or not; perhaps Bob has an opinion ?
But the DMI temperature graph is still dooing crazy delaying tactics on its way to the bottom; and if that is real (why wouldn’t it be ?) that would be consistent (I like that turn of phrase) with the fact that the JAXA ice regrowth; which got off to a good start mid september; right about the time this silly yo-yo appeared in DMI, with the regrowth plot (JAXA) slowly working its way over towards the record low 2007 plot. That trend would certianly jibe with the delay of the temperature drop in the high arctic.
Could any of this be related to what Bob is referring to as regards SSTs ?
Just asking.

“equally well with TSI or any other solar cycle indicator.”
But TSI is inversely correlated, and by all indications neither it or any other solar indicators are the direct cause, as far as I am aware. E.g., as you point out, there just isn’t enough of an energy change between max and min solar activity to drive climate. Yet climate responds to solar cues none the less. How?
CRF appears to be the only candidate for a direct cause, with the sun serving merely to modulate it. According to the theoretical model CRF isn’t sufficient to induce cloud nucleation, but in practice more clouds form when CRF is elevated. And now there is even “proof of concept.”
It would be nice if there were a good (i.e., objective and complete) state of the art review that laid out all the different scenarios, with their pros and cons. Does any such document exist? (something independent of the UN’s tree-ring circus, that is).

Leif Svalgaard (21:39:57) :
As Al Gore says: if you don’t know anything, everything is possible.
You keep rolling out the same mantra’s as if its part of a script to your agenda. I am sorry I don’t go for your “the sun didn’t do it” story. Good science doesnt follow agenda’s, it searches for answers and takes on all areas with interest (dont give me your filter/pseudo science story)
Sometimes I think us Laymen can do it better, the politics are not involved.

In a rather unassuming way Houston Cygnus atratus has landed,
NZ climate summary for october -1.4c a 64 year record clearly explanations are in order.
Coldest October in over half a century
* Oct09_summary.pdf
* Temperature: The coldest October in 64 years, with all-time record low October temperatures in many areas. Exceptionally late snowfalls. Record low October temperatures were recorded on the 4th/5th in most North Island locations, and on the 9th at many South Island sites.
* Rainfall: Well above normal rainfall in the east of the North Island, as well as in Wellington, Marlborough and parts of Canterbury. Very dry on the West Coast of the South Island.
* Sunshine: Extremely sunny on the West Coast of the South Island.
Record or near-record low October temperatures were experienced in many locations, with temperatures more than 2.0°C below average throughout eastern and alpine areas of the South Island, as well as in the lower half of the North Island. Temperatures were below average (between 0.5°C and 1.2°C below average) elsewhere. Overall for New Zealand, it was the coldest October in 64 years (since 1945), with a national average temperature of 10.6°C (1.4°C below the long-term October average). Such a cold October has occurred only four times in the past 100 years. Record low October temperatures were recorded on the 4th/5th in most North Island locations, and on the 9th at many South Island sites.
http://www.niwa.co.nz/our-science/climate/publications/all/cs/monthly/climate-summary-for-october-2009

Leif: Thanks for the Monthly CRF data. I’ve looked for a solar signature in SST data a number of times and never really found it. So I wanted to use the same data in yonason’s link.
yonason:
The use of Monthly CRF and SST data in place of Annual data reveals different results. Leif provided the Thule CRF data in a link above. I inverted it as noted in the graph you linked. I detrended HADISST Global SST data. To remove the effects of ENSO, I shifted NINO3.4 SST anomalies three months, scaled it by a factor of 0.1, and subtracted it from the detrended Global SST data. When I compared the Inverted CRF with the Adjusted and Detrended Global SST, it was really apparent that volcanic eruptions were influencing the SST data, making the SST and CRF data appear to agree in places, so I removed the volcanic aerosol influence using Sato Index data (Scaling Factor of 2).
Of course, removing ENSO and volcanic aerosol influences always leaves a residual, because if you key the scaling on one ENSO event or volcanic eruption, there’s always a residual left on the others. Here’s the result.
http://i35.tinypic.com/2rfu0ld.png
I don’t see a long-term correlation between the two datasets. Some of the wiggles match, but not all.
I’ve examined the solar-Global SST “link” before and you can adjust the scaling factors so that you get a better fit in one portion of the curves, but that throws off the agreement in others.

Leif Svalgaard (20:34:06) :
yonason (20:15:02) :
But TSI is inversely correlated
No CRF is inversely correlated. Note the scale is upside down.
I assume you are referring to the Shaviv paper? (fig.3 here)
http://physicaplus.org.il/zope/home/en/1105389911/1113511992_en/
I hope he’s just mislabeled the axis, because if you’re right, then the whole theory breaks down, because increased CRF has to correlate with increased clouds in order for it to work.
This one I gave above has it right, for both solar irradiance and cosmic rays.
http://cce.890m.com/solar-gcr/images/tsi-vs-gcr-vs-clouds.jpg
Also, see figure 2, here
http://www.tau.ac.il/institutes/advanced/cosmic/Conferences/2002_COSPAR_Houston/CosmRays_WheatPrice1.pdf
The axis appears to be correctly labeled there. (note the excellent correlation over 20 years, too.)
And when TSI increases, CRF decreases, so TSI has to be inversely correlated, again otherwise none of this works. I think they would have been caught on that by now if it were the case?

According to the theoretical model CRF isn’t sufficient to induce cloud nucleation
A model is the expression of what we know from physical law.

Which is why all the Global Climate Models work so well? Models are fine, but depending on them to extrapolate into the unknown can be quite risky.
Besides, the Folks at CERN take the correlation seriously enough to look for the mechanism.
http://cloud.web.cern.ch/cloud/documents_cloud/cloud_proposal.pdf
And you don’t waste those kinds of resources looking for a mechanism for an imaginary process.

Leif Svalgaard (20:34:06) :
yonason (20:15:02) :
……………
……………
Does any such document exist? (something independent of the UN’s tree-ring circus, that is).
Many exists, and that is the problem, as they are contradictory.

I.e., more worms to add to the already overflowing can?
Oh, well, I guess that’s why we’re still at it here. On the up side, one can hardly say the debate is over.

yonason: You wrote, “I’ll leave it there, and wait to see what the CLOUD expts., come up with.”
Joel Norris is one of the cloud experts. In the following 2009 paper, he and Anthony Slingo explain, in great detail, the problems with cloud cover/amount data here:
http://meteora.ucsd.edu/~jnorris/reprints/02_Norris%20and%20Slingo.pdf
With the lack of reliable data, we may have to wait a long time before the cloud experts can come up with anything worthwhile.

Geoff Sharp
Here is a chart showing the data. (There is one line missing from this chart – solar insolation at high latitudes which will have to wait till later).
http://img261.imageshack.us/img261/2127/last3iceages.png
We only see the data for 65N but there is a global solar irradiance value as well. From Berger and Loutre 1991 at
http://www.ncdc.noaa.gov/paleo/forcing.html
And Leif, I was attempting to back up your points. Maybe it didn’t come off right.

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 (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.

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.