Global Oceanic Climate Update for August 2009
Dr. Roy Spencer September 1st, 2009
This is the first of what might turn into a series of monthly updates of some maritime climate parameters monitored by the AMSR-E instrument on NASA’s Aqua satellite. All monthly statistics have been computed by me from daily global gridpoint data produced and archived by Remote Sensing Systems (RSS) under the direction of Frank Wentz, a member of our U.S. AMSR-E Science Team. Since Aqua was launched in 2002, the data are available only since June, 2002. A description of how these products were derived, and where they reside, is provided here.
There are 5 “ocean products”: sea surface temperature [SST]; near-surface wind speed; vertically-integrated water vapor; vertically integrated cloud water; and rain rate. I will present time series of monthly anomalies averaged over the global, ice-free oceans (56 deg. N to 56 deg. S latitude), and separately for the deep tropics (20 deg. N to 20 deg. S latitude). ‘Anomalies’ are departures from the average seasonal cycles in those parameters, which will be recomputed as each new month of data is added.
GLOBAL OCEANS
In the first figure below are plotted the 5 ocean products for the global ice free-oceans (56N to 56S). As can be seen in the top panel, SSTs in August cooled slightly from the unusually warm conditions experienced in July.
I have added linear trend lines to each time series, which you are free to misinterpret as you wish. 
Since the AMSR-E period of record is only 7.25 years long, a calculated trend won’t have much meaning…although it will be interesting to see how long it takes before the climate system obeys the UN’s command to warm, and the SST trend line begins to go uphill again.
How these different variables change relative to each other is illustrated in the following lag-correlation plot of SST versus the other variables. “PDO” is the Pacific Decadal Oscillation Index, while “SOI” is the Southern Oscillation Index (negative for El Nino, positive for La Nina). A discussion of these curves is provided later, below.
TROPICAL OCEANS
The next figure shows the ocean product anomalies for just the deep tropics, 20N to 20S latitude….
…and the lag correlation plot for the deep tropics is next:
DISCUSSION
Using the 20N-20S lag correlation plot as an example, you can see that total integrated water vapor is highly correlated with SST, which in turn is highly correlated with El Nino conditions (negative SOI values).
Also note that sea surface temperature tends to peak after months of anomalously low wind conditions, then falls as wind speeds increase.
Cloud water and rain rates increase as SST increases, reaching a maximum 1 to 3 months after the SST peaked.
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Once again, the use of the word “anomalies” instead of the proper word, “variability”. An anomaly is the departure (and usually a significantly large departure) from normal. It is absurdity to think that there is a fixed normal standard or norm for what is being depicted on these charts.
But then, science has become a Humpty Dumpty world:
When I use a word,’ Humpty Dumpty said in rather a scornful tone, `it means just what I choose it to mean — neither more nor less.’
`The question is,’ said Alice, `whether you can make words mean so many different things.’
`The question is,’ said Humpty Dumpty, `which is to be master – – that’s all.’
Who would have thought that Lewis Carrol would turn out to be a futurist, foreseeing the craziness that “science” has become? We have indeed “gone through the looking glass”.
In the tropics, trade winds play an important role in sea surface temperatures from my own observation of various data. It is nice to see that someone far more credentialed in the field than I reports this. In many cases, sea surface temperatures are more a proxy for wind speeds than anything else.
What is interesting to me is what wind speed is required to produce a sst anomaly of 0 and would that wind speed also be a 0 anomaly. In the diagram above for tropical oceans, it appears that sustained winds of around +0.1m/s anomaly can produce a -0.4C temperature anomaly.
@ur momisugly LarryOldtimer (10:13:56)
“Anomaly” is the correct word; an irregularity. Your problem lies with the normalized value that the irregularity is plotted against.
Perhaps you would be happier with the plots if the normalized value were made a thick line that would encapsulate the common range of “variability”. Of course, that leads to another debate over what constitutes the common range of variability.
You may need to supply your own upper and lower bounds and defend them them when you enter the discussion.
cheers,
gary
Some related info about the SOI (El Nino ) – http://www.dtnprogressivefarmer.com/dtnag/common/link.do?symbolicName=/ag/blogs/template1&blogHandle=weather&blogEntryId=8a82c0bc2315725901239a2e1df10655&showCommentsOverride=false
The Pacific barometric indicator known as the Southern Oscillation Index (SOI) is still acting a little flaky, and is not supporting a trend to El Nino.
The SOI calculation for Monday, Sept 8 is +11.35. The strongly positive figure, of course, is more La Nina-ish than El Nino. During the last 30 days, the SOI was a -0.20. The last 90 days’ SOI is almost exactly neutral at -0.01.
” In the past 8 days or so, from August 31 on, we have seen these SOI values: +12.81 on 8/31; -2.20 on 9/1; +0.54 on 9/2; +5.77 on 9/3; +15.63 on 9/4; +21.87 on 9/5; -4.87 on 9/6; +3.03 on 9/7; and today’s (Tuesday) calculation of +11.35.
This SOI back-and-forth is so far not a sign of a strengthening El Nino. “
So wind mills promote global warming?
Gary Turner(10:36:29) “”Anomaly is the correct word…….” As Humpty Dumpty said: “The question is…”.
Looks to me like nother cold non-Niño winter is about to happen for the NW…
LarryOldtimer (10:13:56) :
Hmm, variability implies to me a noisy signal, not something that might have a trend or can be compared to something
It’s also just a step away from variance, and that implies a comparison to
something like the average/normal/expected values.
I’m happy with anomaly. Mirriam-Webster says:
2 : deviation from the common rule : irregularity
3 : something anomalous : something different, abnormal, peculiar, or not easily classified
I wonder what the world takes for irregularity. Milk of magma?
It is relieving that there is no “end of the world” ahead. All are real nano variabilities.
All are not anomalous ( “inconsistent with or deviating from what is usual, normal, or expected “). Everything is OK. No global warming, no climate change ahead.
Good to know everything is usual, normal and as expected.
What happens if it doesn’t obey the UN command to warm?
This just in:
http://www.kirotv.com/news/20794400/detail.html
I wonder who will prove to be the more acurate forcaster of seasonal climate trends, Fjord horses or the National Weather Service.
So wind, by increasing evaporation, cools the Ocean Surface; this leads to more water vapor and clouds. Pretty straight forward when explained to me.
So, what heats the Oceans?
I think that we all know that higher temperatures would produce more rain, but it is interesting to see the ‘proof’. The warmies think that higher temperatures produce drought, wich i never realy understood.
Robert Wood (11:42:46) :
Some say that it could be the Sun, however some reputed scientists oppose that idea, they think it is CO2 instead.
Jeff in Ctown (11:51:40) : cold, wind, drought
Seems you do understand but this is still interesting.
Cold leads to snow and storage of H2O in glacial ice. Glaciers grind rock into “rock flour” which is spread about during melt season and blown about during the freeze-up season. Glacier periods have been characterized as cold, windy, and dry with development of landforms of loess. Search with the term “loess” and follow some of the links.
I was not aware that “the warmies think.”
“…which you are free to misinterpret as you wish.”
You asked for it!
Judging by your figures, at this rate the entire planet will be covered with ice by 2050!
Cheers Doc Spencer! 😎
Ric Werme (10:53:37) :
I also do not like the term “anomaly”.
I admit I am linguistically biased since in modern greek it is mainly used for human deviant behavior, but also because :
2 : deviation from the common rule : irregularity
3 : something anomalous : something different, abnormal, peculiar, or not easily classified
if accepted at face value, means that there exists a “regular”, a “normal”, and “easily classified” temperature, that one expects the weather/climate to be in stasis and anything outside of it is anomalous.
In no way the chaotic system that is weather and climate can be considered to be in stasis , IMO.
anna v (12:31:57) :
In no way the chaotic system that is weather and climate can be considered to be in stasis
No chaotic system accept a regular driver like the sun, the trouble is we as witnesses do not last too long too observe it. Wait patiently and you will observe regularity.
Gwrs. are the agents of “chaos” 🙂
Very cool post. I see Robert Wood makes the link that cool SST is created by evaporation due to increased wind. An alternative explanation rather than massive heat removal would be the piling of the warm ocean surface water on one coast or another exposing the cooler deep water to the air. Anthony had an earlier post around January sometime demonstrating the piling of hot water along the continental coast . I don’t remember the reasoning given.
Robert Wood: You wrote, “So wind, by increasing evaporation, cools the Ocean Surface; this leads to more water vapor and clouds. Pretty straight forward when explained to me,” then asked, “So, what heats the Oceans?”
The answer lies partly in your opening sentence.
But for a more detailed description that’s reasonably easy to read, refer to “A Global Survey of Ocean–Atmosphere Interaction and Climate Variability” (2004) by Wang et al. Link here:
http://www.aoml.noaa.gov/phod/docs/2004_Wang_etal.pdf
Warning: It includes a gratuitous AGW plug toward the end, but, on the other hand, it takes a big roundhouse swing at GCM biases in the next paragraph.
Interesting that the “lag correlations” charts correlate well with the earth thermostat theory.
On the charts displayed, the ocean SSTs seem to change ahead of the changes in all the other parameters. Have I interpreted them correctly ?
For my understanding of climate changes to be correct the oceans need to independently vary the rate of release of energy with the air then following.
For AGW proponents and some sceptics it is events in the air that occur first with the ocean SSTs and the climate then following.
Which is it ?
Interesting set of data. Along with the word “anomaly”, I do not like the word “brightness” either. But realistically, those animosities stem from the fact that each word has an understood colloquial meaning; but also a specific “scientific” meaning; and the two aren’t necessarily the same.
To me, anomaly, also means something that is out of whack ,and not what it is supposed to be.
But I can accept that it is a standard usage term of climate “Science”, so I am prepared to cut them some slack, and say I’ll adopt your meaning for this purpose; but I still don’t like the concept, but accept that climatologists are used to using it.
But to the good Doctor’s data. Thge SST, and following evap, and further delayed rain, are in Keeping with Frank Wentz et al’s paper from SCIENCE Jul7 7 2007. To me then it is not surprising that evap follows SST s delayed, and subsequently more evap leads to more rain, and also to more clouds (negative feedback)
I’m not a meteorologist; but it doesn’t surprise me that as SSTs go up that eventually surface wind speeds go up; after all isn’t it differential temperatures that create the winds.
So I don’t necessarily associate the increased evap with the increasing winds; to me, both are consequences of the SST increases; so I do not see the wind as being responsible for the evap but more a result of differential surface warming (sea/land).
As to what heats the ocean; simple; direct sunlight, solar spectrum incident radiation, which propagates deeply (many tens of metres) into the oceans. It certainly isn’t downward directed long wave IR, which will be stopped in the top ten microns, and lead to prompt evaporation (and surface cooling).
This will be a nice set of data to get monthly updates on Dr Roy; thank you for taking on the task.
George
Any chance of seeing the lags for 12 months before and after rather than just 6 months before and after ?
Longer would be even better.
The most striking correlation is between SOI and SSTs rather than PDO. I suppose that is logical given that PDO is a statistical artifact.
Is SST always so well matched to SOI ?
If water vapour, rainfall, cloudiness and wind do indeed all follow the ocean SSTs and do not lead them then my hypothesis about oceanic forcing being neutralised by changes in the speed of the hydrological cycle seems to stack up with the evidence presented here.