Yesterday, I indicated I would start showing “slide and eyeball” data comparisons to the IPCC projections. These supplement the comparisons of recent trends to IPCC projections. I made some changes to the graphs based on the advice of visitors.
Here’s the new graph:
Dashed lines represent 2 sigma, based on calculated residuals to linear fits.
Relative to yesterday:
- Brighter more visible colors. (No, I couldn’t see the pink well either. 🙂 )
- Show a trend relative to an earlier period.
- Display lagging 12 month averages instead of Jan-Dec averages. This means the last point displayed will be based on a full 12 months of data.
Why show the trend from 1950?
The ‘slide and eyeball’ technique is purely visual. After someone suggested showing a trend from 1959, I thought it might be useful to simply show trends that bracket what we’ve seen in past history. Graphs are, of course, not self explanatory; still, the decision of which graphs to display does influence viewers perceptions.
Nevertheless, I’ll leave it to readers to ponder the cause of the large difference in trend based on start dates of 1950 and 1975 and say no more for now.
As it happens, I did ponder a bit about the choice of 1950 as a start time. In the end, I select a trend that begins in 1950– the mid century point. This means the start points are the quarter century and mid-century point.
There are several “down-sides”. One is those in charge of the official records of sea surface temperature (SST) have informed the public the measurements during WWII and immediately afterwards may have rather large systematic errors due to changes in measurement techniques. (Some recent measurements may also be affected.)
Speculating based on a Real Climate endorsed graphic, Roger Pielke Jr. suggests the calculated trend since the 50s might drop 15%. (These general sorts of suggestion have put James Annan in a tizzy, but after killing two strawmen, he found that the proposed bucket adjustments could affect trends calculated since 1946 by as as much as 20%. In the end, he admits there may be a series of minor adjustments, affecting temperature, thereby. )
If and when those in charge of data alter the official records for temperatures, I’ll revise the trends on these “horserace” graphs report how much they changed.
Also, when annual average data come out in 2009, I’ll create equivalent slide-and-eyeball charts with annual average data. At that point, I’ll also create a set of graphs including the satellite record. Start dates for trends will be revised accordingly.
The residuals graph
I’ll continue to show residuals relative to the 1975-April 2008 graph, and those from a possible interpretation of the central tendency predicted by the IPCC AR4 projections. For now, I won’t clutter it with other features:
More recommendations on graphs?
Those are the graphs as modified. Let me know if you can read them, prefer other colors etc. Also, feel free to muse about the meaning.
So what if some at other blogs think musing about the data, or possible effects of the bucket – engine inlet SST adjustments is foolish! What are blogs for? 🙂
Note: All images are displayed at 600 pixels. You can click to see 100px wide versions.
Thanks for adding 1950. It will be interesting to see how the bucket/engine inlet adjustments evolve.
ChrisH.
It was a good idea. At first, I thought things would get too cluttered. But I realized the idea that some of the rapid warming after the 70s is due to clearing of aerosols, and some due to the likely temporary interuption in our regularly scheduled eruptions of stratospheric volcanos. If so, it’s useful to show the earlier trend and it’s uncertainty bands. (They are larger of course.)
Naturally, anyone could object and point out the trend since the 50s doesn’t look linear. Moreover, there is a strong
“kink” in the graphs of the forcings used to drive climate models like the GISS Model E that would tend to make those who believe in AGW believe the trend should not belinear between the 50s and the 80s. But, it’s still always worth looking at in a horse-race.
Lucia,
I’ve been a lurker here for quite some time. Quibbling over surface temperature trends etc. is interesting for discussion but does it address a very important issue, that being ocean heat content.
Surface temperatures appear to be but a reflection of what the oceans are telling us, and if they are not continually absorbing heat, there can be no “global” warming.
As I understand in the simplest of terms, short wave solar radiation warms the oceans. Since water (liquid) absorbs 1000x more heat than water vapor (gas), where does that leave CO2?
It has been stated the oceans, ~70% of the earths surface, are responsible for 80-90% of Earth’s warming, so why is all the focus on near surface temperatures? Are we not at the mercy of the oceans?
I’ve yet to have it explained from known physics how increasing CO2 levels contribute to warming of the oceans let alone the troposphere. Is it not true that LW IR in the range of re-emitted IR from CO2 does not penetrate water? How then can rising GHG emissions contribute to increasing ocean heat content?
A recent NPR interview with Josh Willis and Kevin Trenberth reveals the latest data indicates the oceans have in fact not been storing heat, but rather losing. Thus the phrase “where is the missing heat”. Trenberth stated the heat has escaped into space. How can this be?
One need not look further than IPCC AR4 ch05 Figure 5.1 where it unmistakably shows a steep drop in OHC from 2003-2006. According to Hansen et al (Josh Willis co-author) 2005, the “smoking gun” confirmed the global warming theory that “Earth is absorbing more energy from sunlight than it is emitting back to space in the form of heat radiation.” This was based on ten years of data collected prior to 2005.
http://www.columbia.edu/~jeh1/2005/Imbalance_20050415.pdf
Where is the “heat in the pipeline”?
The IPCC OHC data disagrees with the 2006 Lyman report (Argos floats) which he concluded (correction paper published Oct 07) during the period of 2003-2006 there was no statistically significant warming or cooling. Nonetheless, in 2008 OHC has still not increased, but is trending downward even if slightly.
RPS has addressed this issue for well over year on his blog, the latest being:
http://climatesci.org/2008/05/29/new-information-from-josh-willis-on-upper-ocean-heat-content/
JC–
I agree the ocean heat issue is important. I emailed Roger Pielke Sr. and Josh Wilis earlier this year. I’m hoping the annual average ARGOS data becomes available in an easily accessible format soon. When it does, I’ll be posting about that too. But for now, it’s a relatively new product and I don’t think it’s easily available.
So its starting to look very serious guys -0.347C May total -0.77C people are going to start to ask some very hard questions about climate modeling and the money spent on them
http://wattsupwiththat.wordpress.com/
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JC “I’ve yet to have it explained from known physics how increasing CO2 levels contribute to warming of the oceans let alone the troposphere. Is it not true that LW IR in the range of re-emitted IR from CO2 does not penetrate water? How then can rising GHG emissions contribute to increasing ocean heat content?”
Hi JC, let me see if I can help out. There are two mechanisms here.
1. Is the “thermal blanket” effect of CO2. As heat is reradiated from the surface (and the oceans as well) some is trapped by CO2 on the way out, and then reradiated again by the CO2 molecules. Half of that escapes to space, half goes back to the surface. If there is a particular heat balance at some starting point (choose any) and CO2 goes up later, the new balance will be a warmer earth. That is a heat balance model and shows the macro picture.
2. The oceans come into play then as the large scale climatic effects like El Nino/La Nino (also called ENSO) and PDO etc, etc. Simply put this is a cycle where heat from the warmed atmosphere is absorbed by the oceans for a while (La Nina) and a year or two later when the ocean has warmed up, expelled back to the atmosphere. It’s an oscillation in the physical climate system and the heat energy swings back and forth between the atmosphere and the oceans. An analogy would be hitting a spring, it will vibrate back and forth for a while. You can also think of it as a system that has hysterisis in it.
Lastly, the “IR … does not penetrate water” bit. Quite right, it is absorbed by water, and the water warms up. By penetration, I think you mean transparency. The atmosphere is transparent to visible light (as is water pretty much) which is why we can see stars at night and the bottom on the swimming pool during the day. ie. Water and air are transparent to visible light.
But both absorb IR (the atmosphere a little, water more). Which means if you look in IR wavelengths alone it’s like looking through a haze – they are both only semi-transparent to IR and semi absorb IR. An (inexact) analogy is looking through smoke or a fog, the particles or droplets absorb (scatter actually) light and you can’t see clearly.
When oceans or the atmosphere absorb IR they warm up.
(And yes water does also absorb short wave – if by that you mean microwaves. It then reradiates the energy as IR – heat. That’s how microwave ovens work.)
JM
It is easy to explain short wave (direct sunlight) solar radiation heating the ocean; it is self explanatory actually. However, a bit of searching led me to a discussion at Warwick Hughes with a guest blog by Doug Hoyt, solar physicist. His explanation greatly varies from yours with respect to my questions about LW IR absorption by water.
http://www.warwickhughes.com/blog/?p=87
Of note, Hoyt says:
The other problem I have is neither the atmosphere or the oceans have been “trapping” heat for the last several years. Rather, both are headed downward. If CO2 has such great power to trap heat, why are observations diametrically opposed to the hypothesis?
“thermal radiation from carbon dioxide will only heat the upper 15 microns of the oceans”
Once it’s been absorbed by the upper 15 microns and has warmed that layer, where do you think the energy goes? Via conduction it heats the water directly underneath it, ie. the ocean. The flaw in the argument at that link is this:- water is a much better conductor of heat than air. Air is actually a rather poor conductor of heat which is why double-glazing works.
So most of the heat will be transmitted to the water, not “reflected” back into the air. You should be able to confirm this yourself by putting a glass of beer out in the sun, after about 20 minutes it will be so warm as to be almost undrinkable. Water (which makes up the majority of beer) does not reflect heat, it absorbs it.
“The other problem I have is neither the atmosphere or the oceans have been “trapping” heat for the last several years”
If that were the case the average temperature of the earth would be about 33C below where it currently is (ie. around 14-33 = -19C. Since the oceans aren’t in the process of freezing over I think we can safely dismiss that hypothesis.
“If CO2 has such great power to trap heat, why are observations diametrically opposed to the hypothesis?”
Because the oceans are still liquid and you and I are still able to walk around in shirt sleeves.
[btw – this is not in any way a sarcastic post. It is simply a mapping of your question to the observable reality around us. This is the sort of argument mounted in physics discussions all the time, and there is nothing disrespectful about it at all ]
Rather, Warwick Hughes is – IMHO – trying to baffle you with detail, and being very disrespectful of his audience. He’s taking you for a fool.
And JC, to be a little more exact I’ll ping him on this statement:
“Also since the surface layer where the absorption occurs is cooler than the water just below it, there can be no net transfer of energy by conduction, convection, or radiation downwards because it would violate the laws of thermodynamics.”
If you’ve ever been diving (or even snorkling or swimming) I’m sure you’ll have noticed that deeper water is cooler, not warmer. Conduction will work just fine to carry the heat down into the depths.
The entire argument defies observable reality which you and I can confirm in our daily lives.
JC, last comment on this point.
This statement (by Hoyt, sorry not Hughes) is flat out wrong
“it will just redirect the energy back up to the atmosphere much like a mirror, but not exactly a mirror, ”
Contrast with this later statement of his in the same post
“the implied water emissivity is 0.9998”
A black body (ie. something that absorbs everything and reflects nothing) has emissivity of 1, a mirror something close to 0. If water were reflecting IR the “implied emissivity” would be more like 0.01. Hoyt refutes himself.
In support of this I quote from a textbook on my desk right now: “Fundamentals of Statistical and Thermal Physics – Federick Reif, 1965” page 388, sec 9.15, last paragraph (‘a’ is emissivity):
“In the case of a black body a = 1. If one is dealing with radiation in the infrared region, a ~ 0.98 for a substance such as lampblack; on the other hand a ~ 0.01 for a metal such as gold with a well polished surface.”
Water does have the emissivity Hoyt quotes for IR, and you would expect that because it absorbs it. If it were ‘like a mirror’ the number would be more like 0.01.
The man is simply wrong.
JM, Absolutely right. It isn’t just Hoyt who’s wrong – Fred Singer seems to subscribe to it too. In fact, this nutty theory was topic 6 in the NIPCC which was the feature of the Heartland show in March.
The oceans absorb SW and are a nett emitter of IR. And there’s no way it can be a one-way flow. For the oceans to store heat, it’s only necessary for them to emit just a little less nett IR.
JM,
I’m having a little trouble parsing your statement above:
Are you claiming that cooler water at depth demonstrates that conduction transmits heat from the surface to deeper water? I’m not doubting water’s ability to conduct heat, just your ability to explain it. Your real life example seems counter to the argument.
Earle, reread my comment at 3203.
Hoyt is claiming that the top layer of water is cooler than the water at greater depth. Outside of a hot spring I’ve never seen that, have you?
Conduction works when a warm material is in contact with a cooler one, heat flows from the warm to the cold, in this case the surface to the depths.
Hoyt on the other hand is claiming that the depths are warm and the surface cold so that any heat flow into the depths would contradict the laws of thermodynamics.
He’s got it exactly backwards.
JM, I think you’re forgetting the ocean skin layer.
MikeN, I assure you I’m not. I’m saying that Hoyt is making a fundamental mistake. From his posting:
” The implication of this is that much of the radiation emitted will escape directly to space through the IR windows, so it could be viewed as a negative feedback. About 40% of the energy will escape this way.”
What happens to the other 60%? It will be absorbed and cause heating. Hoyt then says:
“the initially absorbed infrared energy cannot be transferred to the ocean depths by conduction (too slow), by convection (too small an absorption layer compared to the size of convective cells), or by radiation (too opaque). … Also since the surface layer where the absorption occurs is cooler than the water just below it, there can be no net transfer of energy by conduction, convection, or radiation downwards because it would violate the laws of thermodynamics.”
Here he says that the surface layer – having absorbed IR, and now being warmer – is in his view actually cooler than the water underneath it.
Rubbish. He’s contradicting himself.
(And just before someone jumps on me, the elided sentence above is his conclusion: ” It must escape by the fastest way possible meaning upwards radiation away from the water. ” Since deeper water is colder that is also rubbish)
He’s basically saying that water cannot be heated by solar radiation. Give me a break. What is it heated by then? Why aren’t the oceans frozen?
JM, “Here he says that the surface layer – having absorbed IR, and now being warmer – is in his view actually cooler than the water underneath it.”
Well, the ocean skin layer is almost always cooler than the water beneath it.
Yes, the ocean skin layer is usually cooler. There’s lots of information here (scroll around).
The reason is that the ocean does absorb sunlight to a few metres depth. It can’t go on absorbing forever (without boiling) so almost all the heat has to exit. It does this by conduction to the surface, then IR radiation up or evaporation, with also some conduction to air. So at the surface, the temperature gradient is reducing upward.
IR from above does not actually have to penetrate; it simply reduced the upward flux, so that skin layer does not cool as much as it otherwise would. If the IR from above increases, then the ocean warms, because the nett upflow is then reduced.
However, if the flux from above did exceed the flux from below, it would enter the water by exactly the same conductive pathway.
Hi Nick, thanks for the link, although unfortunately I wasn’t able to load the content on the page.
I was only nitpicking JM about the skin layer, and although I don’t know much about it all, mostly agree with your post about what is to be expected with more IR, slowing the cooling rate, etc.. However, I’d been under the impression that although there has been quite a lot of good experimental and theoretical work done, there remained considerable uncertainty (ie, measurement error, skin/bulk parameterization, what have you) in estimating the upward fluxes.
Do you know if this has changed much? Or are we still talking like multiples of the expected ~3.7Wm^2?
Nick, I just tried the link again and it loads now. Nevermind my last question, it looks like I should be able to find something in the book, thanks again then.