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April 2012 heats up as 5th warmest month globally
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I think in one go you've just pretty much rubbished the whole AGW argument. The two major oceanic drivers - the PDO and ENSO, obviously have a large effect on temperatures, with the late-century rising coinciding with the warm PDO phase. Factor in the increased station urbanisation and we'd probably see that temperature flatline show a slight cooling trend.
Hang on - as pointed out PDO and ENSO are negative over the last 10 years. If you want to adjust temperatures for them then they'll decrease the previous warming trend but increase the recent trend. You can't subtract from the temperature trend when they're positive and then keep subtracting from them when they're negative.
In any event someone has already gone to the trouble of removing those indexes from the temperature signal
http://www.skepticalscience.com/foster-and-rahmstorf-measure-global-warming-signal.htmlFoster and Rahmstorf (2011) have published a paper in Environmental Research Letters seeking to extract the human-caused global warming signal from the global surface temperature and lower troposphere temperature data. In order to accomplish this goal, the authors effectively filter out the effects of solar activity, the El Niño Southern Oscillation (ENSO), and volcanic activity. The result is shown in Figure 1 below.
I should also note that while you've mentioned UHI a lot and attributed a huge amount of observed warming to it, the UAH and RSS records are both derived from satellite observations and are not subject to UHI influences. Here is a comparison of all the records together with their trends over the satellite era
You're simply not going to make that warming disappear by claiming UHI.
The ocean heat content dwarfs that of the atmosphere and it too is warming, again not a product of UHIWith the increased solar activity and hence shortwave flux of the early century, this stored oceanic heat has probably been slowly released over the past 40 years, and we are now reaching an equilibrium of sorts.
Scientists that do this for a living have considered ways to measure the climate energy imbalance and see if it's approaching equilibrium or becoming more imbalanced. Contrary to your statement above it's the latter, again as measured by satellites which are able to monitor incoming and outgoing energy.
http://www.nasa.gov/topics/earth/features/energy-budget.htmlHansen's team concluded that Earth has absorbed more than half a watt more solar energy per square meter than it let off throughout the six year study period. The calculated value of the imbalance (0.58 watts of excess energy per square meter) is more than twice as much as the reduction in the amount of solar energy supplied to the planet between maximum and minimum solar activity (0.25 watts per square meter).Hansen's analysis of the information collected by Argo, along with other ground-based and satellite data, show the upper ocean has absorbed 71 percent of the excess energy and the Southern Ocean, where there are few Argo floats, has absorbed 12 percent. The abyssal zone of the ocean, between about 3,000 and 6,000 meters (9,800 and 20,000 feet) below the surface, absorbed five percent, while ice absorbed eight percent and land four percent.
If your argument was correct then we'd be emitting more energy than we absorb, since the sea would be releasing energy from a previous solar high. Instead the opposite is true.0 -
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I'm very well aware of how climate works and of what models are, and do not rely on blogs for my information, so less of the pompous attitude please. Are you going to respond to MT's post above? He is a real climatologist, but still puts most of the warming down to natural causes. Does he need one of your crash courses on climatology too then?
You don't seem to be able to grasp what I'm saying about the PDO, or are deliberately misquoting me - or both. Let me try again - maybe a picture will help. The PDO was positive from the 70s up to after the turn of the century, and global warming occured. Further back, it was also positive up to the 40s and similarly global warming occured. It was negative from 40s-70s and global warming stopped. It has now become negative again and hey presto - global warming has stopped. It should continue to become more negative over the next decade or so, so there is nothing to suggest that the trend of the last century will suddenly stop and the leveling or even cooling will not continue. You cannot deny that the temperature record has more or less followed the PDO.
Yes it's not as simple as all that, but for some strange reason you seem to be implying that I am saying that recent warming occured when the PDO was negative. I am saying the opposite, as above. So let's put that one to bed for once and for all.
You also don't seem to know what temperature record curve I am refering to, yet you quote it yourself. But here's a picture of it, if it will help.
About the satellite records....yes, if we're talking about warm anomalies here, then one dataset claims 4 times more warming than some others since around 2003. That is a 400% difference. (EDIT: Looking at it again the difference is actually around 300%). Compare the red to cyan or purple. If these are measured data then why the big discrepency? Which is right? Why are they different? Are surface station records not more reliable? Well, some of them are, but many have been contaminated by urbanisation. Again, I refer you to MT's post on Toronto above - work done by a real climatologist, not made up by me.
Regarding the oceans - I was saying that there is an equilibirum between absorption and release of CO2. That equilibrium gets shifted towards release as the ocean warms, but I did not say that the oceans are a net source. Again that is you misquoting me.0 -
I'm very well aware of how climate works and of what models are
If you knew what models are you would not say things like "hockey stick models" nor would you make claims about whether they predicted temperature trends over a specific time period.
If you knew how climate works you would not argue the troposphere is irrelevant in a discussion of surface temperature., and do not rely on blogs for my information, so less of the pompous attitude please. Are you going to respond to MT's post above? He is a real climatologist, but still puts most of the warming down to natural causes. Does he need one of your crash courses on climatology too then?
There is nothing in MT's post that helps you. His post demonstrates an understanding of the topic in contrast to yours which is all over the place.The PDO was positive from the 70s up to after the turn of the century, and global warming occured. Further back, it was also positive up to the 40s and similarly global warming occured. It was negative from 40s-70s and global warming stopped. It has now become negative again and hey presto - global warming has stopped.
This is the problem for you - you want to explain surface warming with ocean cycles yet the surface does not cool in response to them, only flattens. If the energy heating the surface is coming from the ocean then where is it coming from when the ocean cycle is negative?It should continue to become more negative over the next decade or so, so there is nothing to suggest that the trend of the last century will suddenly stop and the leveling or even cooling will not continue.
Again, what is keeping the surface warm for the last 10 years if the ocean cycle was negative? Something has to warm it all the time since the surface continuously looses energy.You cannot deny that the temperature record has more or less followed the PDO.
Of course I can and even according your own description the temperature record does not follow the PDO but is merely partially influenced by it.
i.e.
Versus surface temperature
This is a very poor match and you have failed to explain why temperatures don't return to the same level when the ocean cycles turn negative, they remain at a plateau which increases further in the next cycle.Yes it's not as simple as all that, but for some strange reason you seem to be implying that I am saying that recent warming occured when the PDO was negative. I am saying the opposite, as above. So let's put that one to bed for once and for all.
I am saying that when we apply your approach of correcting for ocean cycles it increases temperature in the period in which the cycles are negative i.e. the last 10 years.You also don't seem to know what temperature record curve I am refering to, yet you quote it yourself. But here's a picture of it, if it will help.
http://ossfoundation.us/projects/environment/global-warming/myths/images/mwp/ipcc_6_1_large.jpg/image_large
I haven't referred to that graph a single time. I also note the graph you posted does not fit your previous description i.e.I don't put much weight into satellite surface temperature data as it is different to that measured by a sensor at the required 1.5 metres above ground level. The problem with the whole temperature record is that we have three different types of temperatures all in the one curve - proxy, instrumental and satellite. That is bad science.
The graph you presented has no satellite data and simply graphs a number of different temperature reconstructions with the CRU surface instrumental record separately graphed.About the satellite records....yes, if we're talking about warm anomalies here, then one dataset claims 4 times more warming than some others since around 2003. That is a 400% difference.
You eyeballing graphs and pulling numbers out of your head is not data nor analysis.
If you want to claim a 400% difference between records then show your work, not "Look at that bit there, that looks sort of 400% different".Compare the red to cyan or purple. If these are measured data then why the big discrepency? Which is right? Whay are they different? Are surface station records not more reliable?
You're again demonstrating a fundamental lack of knowledge about climate science and science generally.
There are multiple records run by different teams because global temperature analysis is an area of active research. They disagree in areas because of differences of approaches in how data should be handled. The differences between them increase confidence they're close to the right answer, not the opposite as you're trying to claim.Well, some of them are, but many have been contaminated by urbanisation. Again, I refer you to MT's post on Toronto above - work done by a real climatologist, not made up by me.
All of the surface temperature records use different approaches to deal with urbanisation and it's an area of active research. However it's extremely unlikely any UHI correction will have a significant impact on the overall trend.Regarding the oceans - I was saying that there is an equilibirum between absorption and release of CO2. That equilibrium gets shifted towards release as the ocean warms, but I did not say that the oceans are a net source. Again that is you misquoting me.
Yes you did say that. Twice.The atmosphere acts in response to the oceans. The oceans also release more dissolved CO2 as they warm, which has in itself probably contributed to the CO2 record of the past half century.Basic physics says that if the oceans warm, they increasingly release dissolved gases, including CO2. Therefore loss will outweigh aborption through the late 20th century warming.
I am not "misquoting" you and if you keep claiming that I'll have no option but to assume we're not having an honest discussion. If you want to play games go for it but I'm not playing.
Now you still have the same problem: If oceans are merely in equilibrium with their C02 absorption/emission where are 50% of human emissions going? Do you know?0 -
Again you continue with the attitude. My reference to "hockey stick models" was a tongue in cheek swipe at the hockey stick graph, as they show this "hockey stick" rise continuing on unabated to Doom. But if the term annoys you then I will stop using it. Jeez... :rolleyes:
Again, I do know how climate works and that tropospheric temperatures are important. What I am questioning is the accuracy of our measurement of them and how we can claim with the IPCC's "90% certainty" that they are warming at X °C/decade when there is a large spread in the measurement. Then the models are fed these data. Garbage in, garbage out.
You quickly gloss over MT's claims in a further attempt to have a swipe at me. Yes there is a lot in there that supports me - that most warming was natural, and that urbanisation does affect temperature records. Did you even read it? There's too much work there for you to just glide over.
Re. the PDO again. Take a look at the temperature record over the last century. It has more or less followed the PDO. Now zoom out to say a 1000 year scale. The last century's warmings become noise on a greater underlying trend, including the Medieval Warming and Little Ice Age. Zoom out further and we see the Milankovitch cycles and their extreme rapid warming. An everchanging roundabout of changing climate, sometimes of extreme proportions.
People seem to think that the 61-90 average is the ideal normal, and anything warmer or cooler that that is a cause for concern. I don't get why the consequences of a warming climate are invariably cast as bad for everyone, as if everyone will suffer. I have also yet to see the real (not alleged) effects that recent warming has done, or indeed what the warming of the 40s did for that matter. We're hearing the scare stories but where are the disasters occuring? And let's leave media and politics out of the answer.0 -
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I just posted the temperature record over the last century which very clearly does not follow the PDO. It's not even close.
Huh? The warmings coincide very closely with the positive PDO phases. How can you say they don't?The cause for concern is the rate of change. The effect of Milankovitch cycles is felt across thousands of years. We have have every reason to think modern temperatures are unprecedented over the last couple of of thousand years and that the rate of change is unprecedented over a much longer time period.
But the at best ~100 year resolution of the proxy records is not enough to resolve decadal-scale warmings like the recent one, though they do show many noisy peaks of a similar rate all the way back through the ages. All noise of course, but still an illustration of how dangerous it is to state that "modern temperatures are unprecedented over the last couple of of thousand years and that the rate of change is unprecedented over a much longer time period." 0 -
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There's no doubt in my mind that we don't fully understand all this.
Adding greenhouse gases to a steady-state atmosphere should warm it up. But if that leads to high latitude ice melt, especially sea ice, then we get into feedback issues that seemed to show their hand in winter 2007-08. Check the rather rapid decline in global temperatures from autumn 2007 to spring 2008 in my link earlier. This was accompanied by exceptional snowfalls in China and parts of eastern North America.
Melting arctic ice can upset the subarctic equilibrium and so, even in a steady-state atmosphere, large fluctuations could then follow. But as Su Campu has been illustrating, we don't have a steady-state natural variability situation, we have periodic changes in large-scale forcings, notably the PDO but also ENSO and NAO. My own research tends to concentrate more on external drivers, solar activity is clearly on a long-term decline since mid-20th century, but other factors that I examine are assumed to be periodic and cyclical. They are invoked more to explain month-to-month variability and cannot really explain any longer term trends.
I have the opinion (and would readily admit to it being subjective) that what we are seeing since 1980 is a series of natural variations with a background warming added on. I accept that about half a degree of warming can be explained by human activity, perhaps a bit more because if we are now in a cooling trend from background natural variability, then the true AGW signal is likely increasing gradually despite the steady state observations. But I also remain concerned about the complexity of urban effects, how do we really know whether we have totally eliminated them from our study, and in fact, should we eliminate them because large proportions of the planet are becoming urban. The real "money" question is what all of the factors do to the subarctic environment, because that's where climate change will be most critical. Changes may have taken place, but are they fundamental or just cosmetic? So far, I would say closer to cosmetic. Until we get into a regime where polar ice is gone each summer-autumn (worse than the 2007 ice min) and also a regime where Greenland is losing something like 1% a decade of its land ice, I feel that we can "weather the storm" of the slight warming and nothing much will happen to sea levels.
The question may never be resolved. Technological change may eventually subdue the rise in greenhouse gases, the outcome may be in doubt (a rise to values around +1.0 C) and debate may always continue about cause and effect. Sea levels may rise slightly and cause some dislocations, but not the mass dislocations of worst case scenarios. Then a period of colder weather might intrude (this would seem more likely after 2060 for various reasons). In some very distant future year, we might be much more concerned about preventing the onslaught of the next ice age. Future scientists may be looking at ways of generating carbon dioxide. All those rusting SUVs may be hauled out of their garages and put back on the road. :pac:0 -
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