| Archive for Earth Sciences Forum This site is dedicated to the Earth Sciences. We are here for you to discuss issues regarding any aspect of the Earth sciences, at all levels of knowledge. Questions are welcomed, as are open scientific debates. Enjoy!!! |
| Andre |
Current global temperatures.Some easy access data are here:http://data.giss.nasa.gov/gistemp/tabledata/GLB.Ts.txt and here http://data.giss.nasa.gov/gistemp/tabledata/GLB.Ts.txt I plotted the monthly data, the difference and the trend here: 
I wonder why there is that 35% difference in trend. |
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| scpg02 |
It's really hard for people like me to understand these graphs. I have no clue what I'm looking at. | ||
| Andre |
Okay I'll elaborate.
If you look at the two source links you see a lot of numbers, the global monthly temperature differences with a certain standard. You can graph those both as I did for the grey and blue grey graphs. The top grey graph is the series of groundstations of GISS from NASA, the lower blue/gray is the satellite temperatures for the lower troposphere. The graphs are a bit shaky because I used the raw data unprocessed. Usually a running average of a longer period is shown, smoothening the graph and introducing errors. The red graph just shows the difference between the two. Remarkable for instance is the sudden red drop in 1998, which reduces the well known huge el nino spike and suggests a stronger increase in temperatures in the recent years, without that spike, which is very strong in the satellite temps. The solid straight lines show the trend as calculated by the program (excel). And the mathematical equation of those lines is in the boxes. The interesting figure is the number before the X, respectively 0.0194, 0.005 and 0.0144, those are the annual increases in temperature. usually those numbers are given in decades, hence the groundstation trend is 0.194 decrees per decade while the satellite trend is 0.144 degrees per decade and we still wonder about the difference, since the greenhouse hypothesis would require that the lower trophosphere was warming stronger than the surface. |
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| Derek |
Hi Andre,
I don't know if you've seen this, http://nzclimatescience.net/index...task=view&id=177&Itemid=1 - DR GRAY'S REPORT ON BALI CLIMATE CONFERENCE If not, you might have missed this exert, " At the UK Met Office Stand I met Richard Betts. The UK Met Office have a new pamphlet which has two interesting features. First they show officially, for the first time, that the globally averaged temperature of the earth has not only been almost constant for seven years, but that it has recently declined. Betts' explanation for this was "natural variability". It seems that this explanation applies only when the temperature goes down. When it goes up it is "global warming" " End of exert. Yup, that's right, UK Met Office - globally averaged temperature constant or declining, "natural variability" the cause....... NB - I can never seem to get comments posted at the Beeb either, but mine are no where near as well written as yours. I'm just happy to be a skeptic.. 
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| Andre |
Thanks Derek, nice catch
Also it looks like we're heading to another cold record in Holland too, we have three consecutive days of freezing fog. Never seen that before. The result: 
and 
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| Latecommer |
Derek,
I think that when a warmer says something that we believe to be true, we should have a positive response. Just as in our daily lives with those we talk to. If I may be cynical for a moment; The true believers have already shown that they can be influenced quite easily....let's influence (condition) them with praise when they get it right. Perhaps that tactic, along with the empirical evidence that, I believe, shows the Earth heading into a Dalton like minimum, will the tide turn. It, however, will not take long before we find that fossile fuel burning is causing a new ice age. Part of man's arrogance comes from the ability to convince himself that he can control powers greater than himself. Some will allow their mind to shift into neutral to stay in that state of fantasy. Just as a |
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| Andre |
Must show this,
I Shot the most beautiful winter series ever Same bridge today: 
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| Derek |
Hi All,
Sorry I've not been here recently, my lose. What bueatiful pictures, breath taking. I used to live in the Lake District, and have over the years had several peculiar glances directed to me when I've said to people, visit the Lakes in winter they are so much more scenic, and breath taking when they are covered in snow and ice. Sounds daft, but I'd say the colours are far more plentiful as well. Maybe it's the contrast in colours, I'm not sure, but it is THE time to see them. Latecommer, damned good point, I'll endevour to adopt it. Andre, more pictures please. NB - (joke) I have never said Holland is flat and boring... 
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| billiards |
Therefore the Greenhouse effect is completely wrong!!!! 
Andre, you yourself (along with your friend Kristen) have campaigned about how groundstation measurements are biased towards being overly warm ... stations on concrete slabs in carpark next to heating vents for example. Perhaps that might explain the increase trend??? (If not then you cannot criticize these stations as they are equally biased from year to year so would still show the correct overall trend.) Correct me if I'm missing something here. |
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| Derek |
Hi All,
Err, Surfacestation.org (if I remember correctly) has shown several different influences on the US temp record. Movement of sites, the millenium bug, expanding heat island effect, to name just three. Surprising the "effect" of these problems is always upwards...When they are corrected the trend does not seem so, well, strong. (Argueably "the upward trend" of Greenhouse theory has been absent since 1998.) Now it seems SSTs via satelites are at least partially responsible for the met. office (UK) now predicting (sorry should that be projecting...) a somewhat cooler 2008. Because of what their models had not represented properly in the first place, natural variation. In this case La Nina. Natural variation, is that what is up with AGW. Must be coincidence. |
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| Andre |
I agree. The trend in the satellite data is more like 0.13 degrees per decade while the ground stations seem to be around 0.2. So if we would have a hypothetical ideal dataset, corrected for all those artificialities then they migh get pretty close. That's not to say that the warming of the 80-90's is all greenhouse effect. There is also that albedo thinghy of Pallé et al. A tiny bit of theory first, conversion of incoming radiation energy to temperature is basically ruled by the Stefan Boltzman law for Black bodies. E=sigma*T4 Eath however is more grey body, reflecting part of the energy depending on the reflectivity or "albedo" (A), so perhaps take note of the link to see that the basic energy to temperature conversion is governed by (step 4): Te=fourth root of (S*(1-A)/4*sigma)) So variation in albedo (i.g. more or less clouds) is also a considerable factor for the global temperature. Now let's look at Pallé et al 2006, who wonder if Earth temperature and albedo can increase together. So look at fig 2, the reconstruction of Earth's albedo from cloud cover compared with the Earth shine on the dark side of the moon. We see a steady decrease of albedo to from 1985 to 1998 and then a slight increase again. That last trend trend seems puzzling to them, according to the question in the title. But they did not realize that the Earth temperature also stopped rising in 1998 and if they had bothered to correlate the albedo graph with some global temperature graph they could have got the graph below to see instead that the temperature correlate nicely with the albedo (r2 = 57.5%). 
Now if you put the 10% albedo (around a basic 0.3) variation of that period in that Stefan Bolzman derative, you will see that this results in a basic temperature variation of ~2.7 degrees while the actual fluctuation was more like 0.6 degrees. It's likely the light absorption of the ocean, that has acted as the negative feedback here but that also resulted in the infamous ocean warming. So we just showed that the temperature - albedo - solar energy variation nicely correlate with it's governing Stefan Boltzman law and that the ocean seem to act as a valuable feedback to moderate the variation effects. That doesn't mean that we understand why the albedo has fluctuated that much but it also shows that we do not need any greenhouse gas to explain what has happened in the last few decades |
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