Guest Post by Willis Eschenbach
There’s an interesting study in Science magazine, entitled “Ocean Salinities Reveal Strong Global Water Cycle Intensification During 1950 to 2000” by Durack et al. (paywalled here, hereinafter D2012). The abstract of D2012 says:
Fundamental thermodynamics and climate models suggest that dry regions will become drier and wet regions will become wetter in response to warming. Efforts to detect this long-term response in sparse surface observations of rainfall and evaporation remain ambiguous. We show that ocean salinity patterns express an identifiable fingerprint of an intensifying water cycle.
Our 50-year observed global surface salinity changes, combined with changes from global climate models, present robust evidence of an intensified global water cycle at a rate of 8 T 5% per degree of surface warming. This rate is double the response projected by current-generation climate models and suggests that a substantial (16 to 24%) intensification of the global water cycle will occur in a future 2° to 3° warmer world.
Let’s start with salinity of the ocean, and how it varies around the globe.
Figure 1. Mean salinity of the ocean in “Practical Salinity Units” (PSU). Figure 1(D) from D2012.
One thing that we can see in Figure 1 is that where there is plenty of rain, along the equator and near the poles, the ocean is less salty (lower salinity). Conversely, where there is a lot of evaporation and little rain, the ocean is saltier.
Intrigued by their thesis that “dry regions will become drier and wet regions will become wetter in response to warming”, I pulled out my Argo surface data to take a look at the salinity records, and to get some idea of how the salinity varies with time, temperature, and location. What I found agrees with my general mantra, “Nature simply isn’t that simple”.
I started by dividing the globe up into five regions: North and South Pacific, North and South Atlantic, and Indian Ocean. I like to start my investigations by looking at a large scale, and then work downwards. Here’s the records for the Indian Ocean.
Figure 2. Temperature versus salinity for the Indian Ocean. Colors indicate the year that the observations were taken. Click on the image for a larger version.
There are several things that we can see in this plot. First, there has been no obvious change salinity during the decade. The earlier records (red) are distributed very similarly to the later records (blue).
Next, the shape of the curve is interesting in that it shows a very different salinity response at different temperatures. At the coldest end of the scale, and up to about 5°C, increasing temperature yields decreasing salinity. Next, from 5°C to about 20°C, as temperature rises, salinity increases, meaning less rain.
Finally, above about 20°C, increasing temperature correlates with decreasing salinity, meaning more rain.
Now, let’s consider their claim, that with increasing temperatures “dry regions will become drier and wet regions will become wetter”. This claim rests on the reasonable assumption that the salinity is inversely related to rainfall, because the fresh rainwater dilutes the salty ocean.
But here’s the problem with the claim. Let’s take a look at two areas, both with the same salinity, say 35 PSU.
Figure 3. As in Figure 2, with a yellow line indicating ~ 35 PSU salinity.
Note that the yellow line intersects two areas, one warmer and one cooler. Now presumably, since salinity is a proxy for rainfall, the two areas are equally wet, or are equally dry.
Now, if the temperature increases, one of the areas (the one on the left) will show an increase in salinity (decreasing rain), while the other one will show a decrease in salinity (increasing rain).
But we can replicate this result at each level of salinity. At each level of salinity (and therefore rainfall), when it warms, some areas get wetter and some areas get dryer. Therefore, it is not true to say that as temperature increases “dry regions will become drier and wet regions will become wetter”. In fact, some dry regions will get wetter, and some will get dryer, and the same is true for wet regions.
This is just the Indian Ocean, however. Let’s see what the other areas show. Here’s the same graph, for the South Atlantic.
Figure 4. Temperature-salinity plot for the South Atlantic, with the years indicated by colors.
As I said above, nature simply isn’t that simple, and the South Atlantic is different from the Indian Ocean. In the South Atlantic, as the temperature increases, rainfall decreases. Instead of the wet areas getting wetter and vice-versa, all areas get drier with increasing temperature.
Next, I looked at the South Pacific:
Figure 5. As in Figure 4, for the South Pacific
In the South Pacific, we see yet another pattern. There’s not a whole lot of change in salinity as the temperature varies. How about the North Pacific?
Figure 6. As in Figure 5, for the North Pacific.
Again, the change in salinity is much smaller that in e.g. the Indian Ocean. However, the same thing is true—for every place that is dry that will get drier if it warms, there is another place that is dry that will get wetter if it warms.
Finally, for complexity, nothing matches the North Atlantic.
Figure 7. As in Figure 6, for the North Atlantic.
Once again, we see that there are dry areas that would get wetter, and wet areas that would get drier, with a temperature increase. However, there are a lot of areas in the North Atlantic that seem not to be following any general trend … complex nature strikes again.
Having looked at how the temperature is related to the salinity for large areas, I decided to look at how the salinity and temperature changed with time for smaller areas. I started with the Pacific, and I picked an area where I could look at ten-degree latitudinal bands. Figure 8 shows those bands.
Figure 8. Salinity map as in Figure 1. Yellow boxes show the delineation of the areas analyzed.
First I looked at the Northern Hemisphere in the Pacific.
Figure 9. North Pacific salinities by ten-degree bands. Colors indicate from coldest to warmest for each individual band. Purple dotted line shows the average for the entire North Pacific region. Black line shows a 200-point gaussian average of the salinity. “Sal. Chg.” is the salinity change (expressed as a change per 50 years for comparison with the D2012 study, along with the “p-value” for the trend rounded to three digits. “Temp. Chg.” is the temperature change (expressed as a change per 50 years for comparison with the D2012 study, along with the “p-value” for the trend rounded to three digits. “Sal. Anom.” is the salinity anomaly expressed in relation to the area salinity average (purple dashed line). “PA” is the “pattern amplification” discussed in the paper, which is the salinity change divided by the salinity anomaly. Note that some of the changes are not statistically significant (p greater than 0.05).
The claim made in the paper is that when the salinity is high (positive salinity anomaly), the salinity change should be positive with increasing temperature (dry gets drier), as well as the reverse—when salinitiy is low, the salinity change should be negative with increasing temperature (wet gets wetter).
However, in four of the six areas shown above, this is not the case. Nature is simply not that simple.
Next, Figure 10 shows the corresponding chart for the South Pacific:
Figure 10. As in Figure 9, for the South Pacific.
Once again, nature is not cooperating. First, in many areas there is little change in salinity. From 50°S to 40°S, the annual swing in temperatures is 14°C, but there is almost no annual change in salinity. In addition, the overall change is in the wrong direction. For another example, look at the band from 20°S to 10°S. Salinity is above the area average, but despite that, salinity is higher during the cool part of the year. In addition, temperature dropped, but contrary to predictions, the previously high salinity increased …
I append the corresponding charts for the Atlantic Ocean, which show much the same thing as we see in the Pacific—a confusing mix of responses.
My conclusions? Well, my main conclusion is that there is no general “wet get wetter and dry get drier” changes. For every dry area that is getting wetter with increasing temperature, there is another area which is just as dry that is getting drier with increasing temperature.
My second conclusion is that different parts of the ocean react very differently to increasing temperature. In some areas, neither annual nor decadal changes in temperature make much difference to the salinity. In others they are positively correlated, and in yet others, they are negatively correlated.
Does this make the D2012 paper incorrect? I don’t know, because they didn’t archive the data that they used for the 50 year period 1950-2000. It does, however, indicate that as is usual with the climate, generalizations are hard to draw. Humans always want things reduced to simple relationships like “if temperature goes up, wet areas get wetter and dry areas get drier.” Like Aesop, we prefer simple morals for our fables. Unfortunately, nature is nowhere near that simple.
My best to all,
w.
PS—I have not commented on the use of a combination of traditional salinity measurements and Argo float measurements, and I do not find any comments by the authors of D2012 regarding the topic. However, it would seem that it should be discussed and the two measurements compared where they overlap in time and space.
APPENDIX 1: Salinity charts by latitude band for the Atlantic Ocean. See the captions for Figures 8 and 9 for details.
Appendix 2. Data and code (in the computer language “R”) are here as a zipped archive (WARNING: 32 Mb archive). Data is in an R “save” file called “argo temps.tab”. WARNING 2: The code is not “user-friendly” in any sense, and might best be termed “user-aggressive”. It is NOT designed to be run as a single piece.
Neat stuff as usual, Willis. I had read that piece in Science and confidently predicted that you would debunk it, but it’s always amazing how fast you operate.
Some of the p-values in Figs 9 & 10 are given as “p=0” –can you fix?
Willis wrote: “Humans always want things reduced to simple relationships like “if temperature goes up, wet areas get wetter and dry areas get drier.””
Well-said.
Varying aggregation criteria easily introduces statistical paradox, so to learn terrestrial climate fundamentals, we need to pay special attention to variables that are globally constrained.
The education system badly needs a compulsory course for all students: Paradox 101. Generations later, humanity might look a whole lot less goofy than climate & solar scientists do today.
Precipitable Water:
http://i52.tinypic.com/9r3pt2.png
Monthly Maximum of Daily Precipitation:
http://i41.tinypic.com/34gasr7.png
Evaporation Minus Precipitation:
http://i43.tinypic.com/2isvynb.png
Column-integrated Water Vapor Flux with their Convergence:
http://i51.tinypic.com/126fc77.png
Credit: Climatology animations have been assembled using JRA-25 Atlas [ http://ds.data.jma.go.jp/gmd/jra/atlas/eng/atlas-tope.htm ] images. JRA-25 long-term reanalysis is a collaboration of Japan Meteorological Agency (JMA) & Central Research Institute of Electric Power Industry (CRIEPI).
http://i49.tinypic.com/fp1edv.png
http://i49.tinypic.com/219q848.png
“User-aggressive” would also seem to be an apt description of nature as well…
Yes. Indeed seawater gets rid of Triffids too you know. Less sure about what it does to so called climatologists though: where many seem to inhabit a science fiction world of their own where they are invincible. In their dreams anyway.
Kindest Regards
If they cover the 1950 to 2000 time frame, how do they handle the cooling from 1950 to 1978, representing the majority of this time frame? Or do they use somebody’s “adjusted” data that disappears this cooling phase? Do they report “intensification” throughout this period or did it decrease with cooling?
Done with your usual thorough analytic thought, Willis. I appreciate your contributions and thank you for them. It would appear from this analysis that we are faced with another poorly done paper in the name of science. I am disappointed with the dismal performances of much in science today.
Thanks for pointing out an interesting paper, and thanks for interesting play with numbers and dots, but I don’t really see how they connect to each other.
First thing that I can see on the paper is, it’s yet another paper saying that models got it wrong.
Second thing is, it is known fact that in historical times when the temperature was higher than today, water cycle was more intense as well. Among others, some 6000 years ago Sahara was much greener than today.
And third thing is, the approach “that’s nice what you found there but when I analyse the data my way I see nothing” does not prove anything. Looking at your graphs I’d even say that they support conclusions of the paper, but more detailed analysis would need to be done.
Thank you Willis for yet another very readable and informative post and a further example of why the debate is not over.
It keeps me amazed how people try to simplify the climate’s behaviour to match their pre-perceived targets.
Over simplification is good for explaining processes, but not for explaining vast and complex systems (as oceans and climate).
The equation warmer=drier is, on its face, a simpilfied and childish claim.
We know that colder could be dryer too…
Great, Willis. Now why don’t you address what they actually did?
Lead author Paul Durack said that by looking at observed ocean salinity changes and the relationship between salinity, rainfall and evaporation in climate models, they determined the water cycle has become 4 percent stronger from 1950-2000. This is twice the response projected by current generation global climate models.
Your analysis above doesn’t say anything about evaporation.
Obviously none of the reviewers spent any time on any such critical analysis. Presumably they were too eager to affrim the predictibly bad news. When I read my snail-mail issue I was struck by the AGW-catechism tone of the very opening
“Fundamental thermodynamics and climate models suggest”
First of all, fundamental thermodynamics does NOT ‘suggest’, it enforces.
Second, tinker-toy models with harumphy official names are not in any way to be given equivalent judgemental weight to ‘fundamental thermodynamics’.
Third, the only suggestion in this entire paper is by your assumption of ‘fixed relative humidity’. Did you ever think to check any data to see if you assumed correctly? Hint: you didn’t. Did you ponder where all that extra heat is supposed to come from?
Also,, can we drop the ‘Reveal’ in the title? How about using the same word we use in deference to ACLU sensibilities: Ocean Salinities ALLEGE Strong Global Water-Cycle Intensification…
Wow! Not just any old ‘intensification’, but a “STRONG’ intensification, one that they ‘FOUND’ (paragraph 2) in 21st century climate projections. I wonder how hard they had to search for that? Hmmmmm.
They conclude with alleging that in ‘the 2-3 C warmer world’ of 2100, their ‘results’ imply a ’16-24% amplification’. This is twice as bad as what the best Gee-Whiz model had already ‘predicted’
So we’re just plain screwed, folks (but, conveniently, not right away).
I used to read Science & Nature for a weekly knowledge infusion, but now I get the bonus of laughing at their mawkish AGW pseudo-science, then waiting for WUWT to skewer it fully. History before my very eyes!
Oakden Wolf (May 12, 2012 at 9:39 pm) wrote:
“[…] the water cycle has become 4 percent stronger from 1950-2000.”
http://i49.tinypic.com/219q848.png
and if the rain falls back into the sea from whence it came – all the assumptions are invalid.
I enjoyed reading it. Just a comment: “One thing that we can see in Figure 1 is that where there is plenty of rain, along the equator and near the poles” – ice melt around the poles comes into play?
Lance Wallace says:
May 12, 2012 at 8:41 pm
Actually, I’ve rounded the p-values to three digits, so the “0” is correct. Beyond that, the numbers become meaningless.
All the best,
w.
PS—I greatly dislike the term “debunk”, as it implies that the study is bunk. In addition, in this case I haven’t looked at what they looked at, because I don’t have the data. So I definitely am not making any claims that I have debunked anything.
Kasuha says:
May 12, 2012 at 9:27 pm
Thanks, Kasuha. They connect because I am discussing their idea that increasing temperature means that “dry regions will become drier and wet regions will become wetter”. I think I have shown that it is much more complex than that.
Indeed they said that, but I have no faith in the models, so it’s not surprising to me that the models got it wrong, and not particularly worth comment … so I didn’t.
I’d have to see a citation for that. Describing anything that happened 6,000 years ago as a “known fact” seems like it is a bridge too far. Yes, we know that the Sahara was wetter back then … but whether the “water cycle was more intense” back then is pure speculation.
Since nothing can ever be proven in science, I don’t understand your point. I am not trying to prove anything. I’m trying to show that nature is complex, and that simple conclusions may not be warranted. In addition, if the result of one analysis differs from another analysis, that is valuable information.
You’re welcome to say that, but unless you actually point out some errors in my logic, my facts, or my interpretations, it doesn’t mean much.
The problem I see is that some of the results that I highlight support their theory (in some places the wet is getting wetter and the dry is getting dryer with increasing temperature), in other locations the temperature is rising but the opposite is happening.
Which is my point—nature simply isn’t as simple as they make it out to be.
All the best,
w.
heh-
“Since nothing can ever be proven in science”
prove that one!
Oakden Wolf says:
May 12, 2012 at 9:39 pm
Thanks, Ogden. The reason I don’t address what they actually did is because as far as I know they didn’t archive the data they actually used. If you can provide that, I’ll take a look at it. Instead, I used their study as the departure point for investigating their general claim, which was that “dry regions will become drier and wet regions will become wetter in response to warming”.
Meaningless to me. The models are known to perform no better than chance regarding precipitation, and this study simply confirms that. Why should I care? Instead of looking at the models, I looked at the real world, and I learned a lot along the way. That’s why I do science, not to establish a claim, but for the joy of learning. I learned a whole lot about salinity and the ocean that I didn’t know.
In the process, I think I have made a reasonable case that the Argo data doesn’t support the ‘wet gets wetter and the dry gets dryer’ meme. But heck, if you can find fault with the case I made, go for it … just don’t waste your time busting me for not discussing the models.
True dat … and the reason is because neither I nor the authors have much data on evaporation. The authors fill that gap with models. Me, that’s not my style. Instead, I follow the lead of Robert Heinlein, who said:
So that’s what I do. Every graph above is observations about the real world, in other words, facts. I just follow them and see where they lead. Your conclusions from those facts may be different than mine, that’s science. I just play the facts cards face up and draw what seem to me to be the conclusions.
Regards to you,
w.
DavidA says:
May 12, 2012 at 10:04 pm
Indeed it does, you can see it in the areas of very low salinity at the very left edge of the temperature/salinity plots.
w.
Willis, it almost looks as if the graphs of the oceans need a 3rd dimension. Have you looked at that possibility?
Ah, the map is strikingly different from the territory, it seems!
Has any consideration been given to how ocean currents contribute to the time evolution of salinity at any particular place as I’m sure ocean currents also contribute to evaporation and moving salty water? I assume salinity arose from salt deposits close to the seabed that are now exhausted (zero sum game) or is salinity subject to sources and sinks in any sort of way? Without consideration of these points I can’t see how conclusions can be drawn from the data or how the original predictions could be sensibly made.
“dry regions will become drier and wet regions will become wetter in response to warming”
Sounds cute, but you don’t even need graphs to sense that this doesnt necessarily work. A region which is dry because it is next to an adjacent cold area, will tend to get wetter if the adjacent cold area heats up, because the cold area is no longer as cold. So a warmer world, for these areas, will tend to make these dry areas wetter.
An example is the Sahara, it is well known to be wetter when the world was warmer in the Holocene, probably for the same sort of reasons as above; when adjacent Europe/Atlantic is colder, the Sahara is drier. The Amazon is also drier when colder, as in the Ice Ages.
Another example is the continental west coasts, which are dry because of the cold currents next to them, when this cold water heats up, they tend to get wetter-which is happening in the NW of Australia (but not in the SW of Australia, curiously).
Thank you Willis Eschenbach for another beautiful exposition of ARGO data. And the thought provoking article. I also want to thank you for the amazing discussion produced from your Bern Model article. My understanding of the CO2 cycle puzzle was greatly enhanced. Thank you to all the great posters rgbatduke particularly but all. I really learned a lot, completely new conceptualization of the process by the descriptive words of rocket science and for simplicity, diagrams.
Only on WUWT !
Willis
I love your deconstructing work. Is there any way you can set it all on a more complete historical and objective basis, I mean, something like:
Nature etc major climate publications….. xxx
Same publications deconstructed by Willis here …. yyy
Same publications deconstructed by others here …. zzz
Roots of studies in alarmist statements… jjj
Conclusions for Science…… kkkkk
– well, written-up in a way that is a bit more, what is it, nuanced than that! Perhaps even a book. You know I still dispute your conclusions re some of the radically new material that challenges long-accepted physics and maths. But these deconstructions of yours, where standard methods and standard accepted laws of science are used, or rather, as you show, abused, and commonsense and patterned complexity are neglected in favour of shocking conclusions to trivial studies, are IMHO really important.
Willis, re evaporation – you may have seen the paper by Roderick et al in Geograpical Compass 2009 http://biology.anu.edu.au/CMS/FileUploads/file/Farquhar/271RodericketalPanreviewIGeogCompass2009_000.pdf
It shows pan evaporation reducing over the last 50 years contrary to expectations. I think Roderick was side lined at ANU as a result.
As the climate models are out by about a factor of 2 in their atmospheric temperature predictions (and probably rather more due to the problems with the pre-satellite surface temperature data), then their ocean evaporation predictions are wrong by a factor of 4 (or more).
Which indicates to me the increased salinity is predominately an increased solar insolation effect, with some contribution from increased winds.
Although these causes will increase the speed of the hydrological cycle.
Which leaves us with a problem. If the hydrological cycle is increasing, why isn’t global precipitation increasing?
http://cics.umd.edu/~yin/GPCP//ASSESSMENT/assessment.html
And why aren’t clouds increasing?
http://journals.ametsoc.org/doi/abs/10.1175/JCLI3461.1
The answer is (IMO) decreased cloud seeding and precipitation causing aerosols, which is also the cause of the increased solar insolation.
“If the hydrological cycle is increasing, why isn’t global precipitation increasing?”
Our measuring systems aren’t up to the task as yet.
“And why aren’t clouds increasing?”
Clouds seem to decrease when the sun is more active leading to more solar energy into the oceans and a warming system. That is contrary to established climatology but it is what happened during the late 20th century.
According to Earthshine data cloudiness has been increasing since the late 90s which coincides with the declie in solar activity and a number of other changes including the cessation of warming.
Svensmark says that the reason is GCRs varying inversely with the level opf solar activity. I say it is because an active sun draws the air circulation poleward widening the equatorial air masses in particular the subtropical high pressure zones with their descending air which dissipates clouds. The opposite when the sun is less active.
Willis’s observations would be accounted for by latitudinally shifting climate zones.
Note that highest salinity, lowest precipitation and highest sea surface temperatures are all under the subtropical high pressure zones in each hemisphere.
Expand and contract those zones in line with an external forcing such as the sun from above or an internal system forcing such as the oceans from below and all the pattern changes are readily explicable.
Note too that those climate zone shifts are a negative response to the solar or oceanic influences. They change the rate of energy transfer from surface to space in order to keep the system stable.
The same response would occur with more CO2 in the air but miniscule and unmeasurable compared to the effects of sun and ocean.
In the pan evaporation study above note the outliers.
Large increases in evaporation in hot dry climates (Israel and Kuwait) and large decreases in hot humid climates (Thailand and India).
I’ll suggest that is due to increased solar insolation combined with increased humidity. The former being more important in dry climates and the latter more important in humid climates.
cementafriend says:
May 13, 2012 at 1:40 am
I’d seen such studies, although not that particular one. The reason for the reduced pan evaporation in the last while is still a mystery as far as I know. I haven’t seen what I thought was a cogent explanation, although one may be out there.
Thanks,
w.
Willis, I forgot to link to Roderick’s second paper which I have been looking for but only just found on the website of one of the secondary authors Prof Farquar http://biology.anu.edu.au/CMS/FileUploads/file/Farquhar/272RodericketalPanreviewIIGeogCompass2009_000.pdf
I think Farquar has broken from the Climate Dept. at ANU which is full of alarmist. The paper gives some reasons for the decline. As you say in your post nothing is straight forward.
Willis, I should have mentioned that I have had Rodrick’s first paper for some time but I found the link I had no longer works, when writting my comment. I then searched on the ANU site and that brought up Farquar and the link that I gave earlier (which worked before I posted it). I then noted the second paper (above which also works) which I have been looking for since I found the first.
>>> Among others, some 6000 years ago Sahara was much greener than today.
I think it is more likely that the ITCZ, and there fore the position of the Sahara, moved south a bit. It would not take much of a movement, to make much of North Africa wet and flora-fauna productive.
Its easier to spot ancient decicated flora and fauna in the Sahara, than confirm an ancient arid zone south of the present Sahara.
.
For some reason the title brought Isak Dinesen to mind.
Two Comments…
One:
The original paper and your commentary seem to ignore Thermohaline Circulation?
http://en.wikipedia.org/wiki/Upwelling
Deep water upwelling to the surface is a very common phenomenon and surface temperatures can be much lower than the “normal” ambient surface temperature. Also, deep water tends to be much more saline than surface water, so typically if you have a relatively low surface temperature you will have a correspondingly high salinity. Simply correlating surface temperature to surface salinity is ridiculous.
Two:
Re pan evaporation. The paper “Pan evaporation trends and the terrestrial water balance” insinuates that the reason the pan evaporation is declining is that water in the surrounding terrain is evaporating at an increased rate due to global warming, increasing the moisture in the air so it is “harder” for the water in the pan to evaporate. (An alternative theory might be that pan evaporation is declining in line with global cooling…)
Willis,
Nice work going through the information you had available. I think it is important that you segregate the debunking between the science done or attempted in the paper and the presence of unfounded conclusions based upon opinion. These people might have gotten a lot of science right in collecting and processing the data. However, it would seem that they lack your skills in deconstructing what they’ve done and apparently any skill to form an opinion based upon their what is actually in their data without resorting to warmist hype. Perhaps a few examples such as yours might convince them to improve those skills and avoid future embarassments from the pitfalls of rash claims that are unfounded from their results. Besides, james hansen is the master of leaping to conclusions not supported by existing data or theory. These guys have a long ways to go to reach hansen’s level.
Willis Eschenbach says:
May 12, 2012 at 10:47 pm
Which is my point—nature simply isn’t as simple as they make it out to be.
True. Also, it appears – “they” are as simple as nature makes them out to be.
🙂
Is there nothing AGW theory doesn’t predict? More rain, less rain, floods, droughts, heavy snow, less snow, more hurricanes, fewer hurricanes. It might be nice for someone to compile all the weather/climate “extreme” predictions on a single page, so we know what we’re up against in the future, because I’m starting to lose track…
umm .. quick question:
I haven’t looked at the internals of the sensors used to get the data but it seems possible to me that the salinity measures are affected by the density of the solution and thus by the interaction between local (near the sensor or sampling point) surface temperature and local depth. If so, you’d expect the north atlantic ridge to combine with north atlantic weather to produce results very different from those you get in the pacific basin with indian ocean floor topology and local surface weather producing a kind of halfway house between them. So, question: do marginal changes over time in the data outside estuarial plumes reflect rainfall or something else?
AGW promoter claims seldom if ever hold up under scrutiny. AGW believer media seldom if ever bother to check the promoter’s claims.
AGW true believers nearly always accept promoter claims in believer media without question.
From the “Science” article abstract: “…observed global surface salinity changes, combined with changes from global climate models, present robust evidence of…”
Output from climate models does NOT CONSTITUTE EVIDENCE, let alone robust evidence! But this statement is clear evidence that yet another line has been crossed by the alarmists, and that they think model output IS evidence. This is a crime against science.
Let me rewrite this sentence to make it scientfically correct: “…observed global surface salinity changes, combined with changes from global climate models, suggest a correlation between…”
Thought provoking stuff. Especially that vertical line in Fig. 7 which is suggestive of a phase change [i.e. sea-water freezing/ ice melting] and the sinking of the resulting higher density waters in the far Northern/Polar regions..
This graph shows the isohalines by temperature and salinity.
http://linkingweatherandclimate.com/ocean/figs/density2.png
Fig. 6 is also pretty cool. Look at the scarcity of data points below 0 degrees Celsius in the North Pacific as compared to the other polar regions. Presumably that is due to both the net Northward movement of water through the Bering straits and the inability of large quantities of ice to escape from the Arctic? Or might it be a data artefact due to not actually having Argo floats reaching the higher latitudes in significant numbers?
typo correction.
The link I gave is for “”Isohalines by Temperature And Density”
Thanks Willis for another great examination. I am amazed at the work you put into each article.
Regarding comments on evaporation, it seems to me that if the atmospheric RH% is dropping, so is evaporation. http://i38.tinypic.com/30bedtg.jpg
What is a “water cycle”?
Fascinating as always. Some of your’ plotting/graphing is rather beautiful.
Reminds me of ‘flocking starlings’ if you know what I mean.
Duncan B
Mickey Reno says:
May 13, 2012 at 6:43 am
From the “Science” article abstract: “…observed global surface salinity changes, combined with changes from global climate models, present robust
evidencespeculation of…”There – fixed it.
I think the Argo plots are fascinating. You can plainly see that the least variation of salinity occurs at 4°C – the maximum density of water. The bifurcation in the N Atlantic and N Pacific plots show the local effects of fresh water from ice – not much ice around when the water reaches ~8°C according to those plots. As someone else mentioned, the freezing line at ~-2°C is also very evident and clearly shows a slope to a higher temperature at lower salinity.
Brilliant plots!
George Steiner says:
May 13, 2012 at 8:13 am
http://www.funwatercraft.com/
/sarc
One might also be tempted to conclude that for the N Atlantic the cloud of points at high salinity might come from the Sargasso Sea (the N Atlantic gyre).
Willis Eschenbach says:
May 12, 2012 at 11:43 pm
DavidA says:
May 12, 2012 at 10:04 pm
I enjoyed reading it. Just a comment: “One thing that we can see in Figure 1 is that where there is plenty of rain, along the equator and near the poles” – ice melt around the poles comes into play?
Indeed it does, you can see it in the areas of very low salinity at the very left edge of the temperature/salinity plots.
w.
My initial reaction to your salinity plots was of considerations of evaporation, rather than addition of freshwater through rainfall (or lack of it). Most of the plots are quite tight at low temperatures, consistent with comparative low surface evaporation rates relative to higher temperatures. Comparing surface salinity with absolute and relative humidity data make be interesting (and I have no doubt it’s been down – I’m long out of the literature).
“…consider their claim, that with increasing temperatures “dry regions will become drier and wet regions will become wetter”. This claim rests on the reasonable assumption that the salinity is inversely related to rainfall,…”
Others have mentioned the melting of ice seasonally, rain on the sea and the thermohaline circ. let us add freshwater return flow to the sea froml the land to confound the simple evap-temp relationship. I do note that the salinity appears to peak roughly around 25C or so in all the graphs. Couldn’t be another (unknown) “governor effect” could it? Also, every time these fellows try to predict a calamity with warming, they unwittingly find a negative feedback: the hotter sea results in evaporative cooling and cloud-rainfall cooling in their “wet region”, plus cooler water return flow to the sea. Remember the other paper about the melting ice cooling the N Atlantic Gulf Stream and causing things to get cold in Europe? – another negative feedback. Having had most of their palette of disasters fall apart, they have sought to repair them with “new” effects and theyd all have negative feedbacks.
kMc2 says:
May 13, 2012 at 4:31 am
Well spotted, it is a quote of hers.
w.
Mark Cooper says:
May 13, 2012 at 4:32 am
Thanks, Mark. Since the graphs show a very clear and distinct pattern connecting temperature and salinity in all the world’s oceans, you’ll have to explain why investigating that pattern is “ridiculous”. It would be ridiculous to investigate it if there were no pattern. But since there is a very obvious pattern which relates the two, it would be ridiculous not to investigate it and try to understand it it.
w.
Chuckarama says:
May 13, 2012 at 5:56 am
Chuckarama, see the WarmList …
w.
Paul Murphy says:
May 13, 2012 at 6:21 am
Good point, Paul. In this case, the salinity data I’m using is corrected for temperature and pressure.
w.
Mickey Reno says:
May 13, 2012 at 6:43 am
Thanks, Mickey. I’ve been beating that particular drum for years. Computer output is not evidence of anything but the beliefs, ideas, and misconceptions of the computer programmers …
w.
George Steiner says:
May 13, 2012 at 8:13 am
Good question, George. The “water cycle” is the name given to the complete cycle of evaporation-condensation-precipitation that the water undergoes in shuttling between the earth’s surface and the atmosphere.
w.
Kasuha – May 12, 2012 at 9:27 pm
Willis Eschenbach – May 12, 2012 at 10:47 pm
——–
Silver Ralph – May 13, 2012 at 4:26 am has it best but not quite. According to the investigations I saw on ancient Sahara it was a change in the Earth’s tilt and/or precession position relative to it’s orbital point. Ground penetrating radar has found all sorts of river courses and ancient lakes from about 6,000 to 12,000 years ago. I don’t have the references handy but I suspect a little bit of Google and some archive searching on NatGeo will turn up the information.
Billy Liar says:
May 13, 2012 at 8:44 am
Thanks for the compliment, Billy. I’m of the opinion that if you can’t see a given effect in a graph, it is a third order effect. And because I am a graphically oriented person, and have made good money with my art work, I constantly strive to present scientific data in a way which is both informative and lovely.
All the best,
w.
Billy Liar says:
May 13, 2012 at 8:52 am
One might also be tempted to conclude that for the N Atlantic the cloud of points at high salinity might come from the Sargasso Sea (the N Atlantic gyre).
The areas of high salinity are strikingly neatly delineated. Do they match any ocean features? If so, why?
JF
Kasuha says:
May 12, 2012 at 9:27 pm
…”Looking at your graphs I’d even say that they support conclusions of the paper, but more detailed analysis would need to be done.”
The above graphs in no way support the paper; quite the contrary.
Should have gone to Specsavers!
Willis Eschenbach says:
May 13, 2012 at 9:47 am
Mark Cooper says:
May 13, 2012 at 4:32 am
… Deep water upwelling to the surface is a very common phenomenon and surface temperatures can be much lower than the “normal” ambient surface temperature. Also, deep water tends to be much more saline than surface water, so typically if you have a relatively low surface temperature you will have a correspondingly high salinity. Simply correlating surface temperature to surface salinity is ridiculous.
Thanks, Mark. Since the graphs show a very clear and distinct pattern connecting temperature and salinity in all the world’s oceans, you’ll have to explain why investigating that pattern is “ridiculous”. It would be ridiculous to investigate it if there were no pattern. But since there is a very obvious pattern which relates the two, it would be ridiculous not to investigate it and try to understand it it.
w.
Willis, Because it is common knowledge amongst oceanographers that the link between surface salinity/ temperature anomaly is (almost) entirely due to upwelling/sinking and has (almost) nothing to do with precipitation in the open oceans/seas. it’s oceanography 101… hence use of word ‘ridiculous’
For example, the Barents sea has almost zero precipitation- the air is as dry as the sahara, it sucks moisture out of the sea water causing salinity to increase to 37+ SPU – but surface water has SPU of 34/35 because the denser 36+spu has already sunk below the surface…
As you point out, the system is far more complex than a simple relationship between rainfall and surface salinity.
Willis, I notice the data points that showed changes that would be caused by freezing temperatures. Are any of these deep in the ocean in mid latitudes? How deep do the Argo
floats dive?
Another pleasurable read. Thanks.
Willis Eschenbach says:
May 12, 2012 at 11:39 ……………………
“So that’s what I do. Every graph above is observations about the real world, in other words, facts. I just follow them and see where they lead. Your conclusions from those facts may be different than mine, that’s science. I just play the facts cards face up and draw what seem to me to be the conclusions.
Regards to you,
w.”
——————–
Well said w. It’d be better if more ‘scientists’ would play their fact cards face up. Everybody gains.
By looking here (you might need to click over to the Feb 2010 listings):
http://www.worldclimatereport.com/index.php/2010/ 02/24/update-on-global-drought-patterns-ipcc-take-note/
and using this paper:
Sheffield, J., K.M. Andreadis, E.F. Wood, and D.P. Lettenmaier. 2009. Global and Continental Drought in the Second Half of the Twentieth Century: Severity–Area–Duration Analysis and Temporal Variability of Large-Scale Events. Journal of Climate, 22, 1962-1981
you’ll see a group of scientists looking into the theory that with warming, you should see a pattern of increased drought.
Naturally, with several drought indexes to choose from, they had to come up with a way to see GLOBAL coverage.
They picked this:
“…Soil moisture is a useful indicator of drought because it provides an aggregate estimate of available water from the balance of precipitation, evaporation, and runoff fluxes…”
So, they used a popular hydrologic simulation model to estimate soil moisture levels at the 1º latitude by 1º longitude resolution for land areas of the globe for the period 1950 to 2000.
What they found was simply amazing.
Sheffield et al. note with respect to global and continental droughts” “…The longest duration drought was 49 months (4 yr) in Asia from 1984 to 1988, closely followed by the 1950–53 North American drought (44 months)…”
Now, here’s where the counters jump in. They’ll find a drought index somewhere that negates the findings, or they’ll claim cherry-picking (only used the period from 1950 to 2000) and missed the dust bowl era and the recent Texas and Mexico droughts.
Still, they managed to find a drought back in 84-88, when the CO2 levels ranged from 344.24 – 351.47. You’ll see that we crossed the deadly upper limit of CO2 (350ppm) during this time.
http://data.giss.nasa.gov/modelforce/ghgases/Fig1A.ext.txt
“…The most spatially extensive was the African drought of the early 1980s, which reached its peak extent in April 1983 when it covered over 11 million square kilometers…”
Again, this extreme drought occurred when the CO2 was BELOW the magic 350ppm level (342.53).
The telling parts of their research, their time series plot for the globe and for various continents shows no upward trend whatsoever.
Using their data, “…The mean number of global droughts > 500,000 km2 occurring in any month is about 4.5 (or 55 yr-1) with a standard deviation of 1.6. This time series is quite variable and indicates several periods of increased global drought activity: the mid-1950s, 1960s, late 1980s to early 1990s, and late 1990s. The mid-1970s to mid-1980s are characterized by the lowest number of droughts, apart from a short burst of activity around 1976–77. The year with most drought months is 1992..”.
In other words, Sheffield et al. analyzed drought patterns at the global scale for the period 1950 to 2000, and found no evidence to support claims of increasing drought activity.
So this paper (D2012) “proves” that “dry regions will become drier and wet regions will become wetter in response to warming”, then Sceffield et.al. proves the opposite.
W: Just curious: have you not yet found even ONE scholarly pro-AGW scientific article that you cannot take apart in 3-4 pages?
Retired Engineer John says:
May 13, 2012 at 5:00 pm
Sorry for my lack of clarity, Engineer. All of my data is from the surface. Most of the Argo floats dive to about 1,000 metres, with the remainder going deeper, to almost 2,000 metres.
w.
According to Unisys the oceans are not looking very warm just now (even with their biassed color system with no neutral colour), especially the North Pacific.
“Durack” is Russian for idiot.
FIVE years ago, Climate Commissioner Tim Flannery predicted that the nation’s dams would never be full again and major Australian cities would need desalination plants to cater for our water needs.
Yesterday, in his latest report, he said “climate change cannot be ruled out” as a factor in recent flooding rains, which led to some of those dams overflowing.
As Willis notes, the climate is complicated.
We cant blame the desalination plants for altering the salinity, as far as I am aware they have never been turned on. Perhaps next they should build a salination plant, just to be on the safe side. Its easy spending other peoples money!
Dear Mr. Eschenbach
First of all I’d like to say I highly appreciate that you find my posts worth discussing. Now if you let me I’d like to elaborate a bit on what I posted above.
Regarding Roman warm period, green sahara and changes in (among others) water cycle connected to it, I believe I have last met them mentioned in one of last year’s Heartland Climate Conference videos. Now while I agree with you that calling something 6000 years old a fact is a bit of overstatement, calling that a speculation is also not quite appropriate. There are better scientists than me and you considering these.
Regarding your article, the main fault in your logic I see is that you are not disproving the discussed paper at all. If you wanted to disprove it, you’d replicate their analysis, find the same or similar result, then explain what’s wrong on such approach to analysing data, fix for that error and show that when the same analysis is performed with the error accounted for, no such result appears. Nothing of that I can see in your article. You perform a completely unrelated analysis and your only conclusion is ‘nature is not simple, I don’t see it there’.
You’re not even trying to identify and distinguish ‘dry’ and ‘wet’ places. You don’t consider that salinity may change with latitude and the same salinity might indicate dry place at one and wet place at another latitude. You’re not evaluating correlations between temperature and salinity in different places. And you’re not considering how much of statistical significance there is. You just put everything into one huge blender and spill the result on a graph.
The resulting graphs are interesting, I admit. But they do not have anything to do with the paper.
Kasuha says:
May 16, 2012 at 3:58 am
Thank you, Kasuha.
The problem is that you mixed up what we do know (the Sahara was indeed green in the past) with what we don’t know (the water cycle was more intense). In addition, you did not give any citation to the work of the “better scientists” you say studied it … but despite that lack of anything to back it up you call it a “known fact”. If there is indeed work from the “better scientists” showing that the water cycle was more intense, then you need to show it.
The link to their paper, as I discussed above, is that they claim that the wet areas will get wetter and the dry areas will get dryer. In Figure 3, I show that for any given wetness or dryness, there are areas that will get wetter, and areas that will get dryer.
In other words, I have falsified one of the main tenets of their paper, the claim that “dry regions will become drier and wet regions will become wetter in response to warming”. As a result, I’m unclear why you say I am not falsifying the paper.
You say I “don’t consider that salinity may change with latitude and the same salinity might indicate dry place at one and wet place at another latitude”, but I’m not the one making the claim that salinity is a proxy for rainfall. It is their claim, and not mine, that the salinity can be used as a proxy for the E-P balance. I am merely showing what happens when you follow their logic.
Look, Kasuha, as I said to someone above, I have shown what I can show with the data I have, because they have not archived their data as used. If you can come up with their data, I’m happy to look at it. Until then, what I can show and have shown is that their underlying claim is incorrect. And whether you like it or not, that is indeed discussing and falsifying their paper.
w.