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#23876 - 10/16/07 04:13 PM Re: Greenland Melt Record High [Re: Chris]
John M Reynolds Offline
Senior Member

Registered: 08/14/06
Posts: 174
Loc: Canada
Amaranth, my link works in Opera and worked just now in firefox.

You will need to prove your theory that the oceans are warming. According to Stephen Richards (http://www.climateaudit.org/?p=1882#comment-128209), "[the MET Office] may also have noted that world sea temperatures are falling..."

In your http://www.scienceagogo.com/forum/ubbthreads.php?ubb=showflat&Number=23840#Post23840 post, you said that "Most uncertainty is still in cloud parameterization and of course socio-economic projections..." That is wrong. The most uncertainty is with the oceans response and, more importantly, life's response to increased OCO levels. A few years back, salps were found to be flourishing. They transport carbon quickly to the bottom of the ocean. Beyond biology, there has also been the realization of the dirty snow positive forcing in, primarily, the arctic.

"Water vapor feedback: Strongly positive, but still some uncertainty in its magnitude due primarily to the upper troposphere contribution"

This is not credible. You say it is strong, but uncertain. Besides failing to quantify the level of uncertainty, you are missing the link between water vapour and clouds which is a negative feedback (reflection of the sun's energy). You cannot separate them. I have no idea why you suggest that coulds could have a negative feedback (even if small), but the models do not take that into account. You say the "models produce..." but that is backwards. It is not the models producing, it is the models working the way they are programmed. It is not magic. If clouds are entered with a positive feedback formula, then the models will output that as the forecast.

"...the IPCC (2007) report clearly show the temperature trends in the atmosphere are in line with the greenhouse forcing and not explainable by natural variability." This is wrong. The signature of warming for anthropogenic forcing has not been realized. The computer models show that anthropogenic warming will have a significantly different warming signature on the atmosphere above the tropics. Those models do not match the observed data as shown in the IPCC 2007 report. You are placing too much faith in the models.

You want it in the form of a question? Fine. From where did the extra energy come in 1998 to make it such an anomoly? How about why would El Nino or La Nina warm or cool the earth when they just transfer energy? As El Nino warms North America, it cools much of Asia. That indicates that there is a problem with the temperature record. Too much weight is assigned to North America.

You explain the theory very well, (The rapid rise of carbon dioxide is more than the slow response time of the oceans can keep up with and you get more solar radiation coming in than infrared going out, and you heat up), but you do not mention that the theory does not match observations. And I am still waiting for you to explain why, in light of increasing OCO levels, has the temperature not been increasing steadily over the past 7 years? This happened around 1991-1994, but that was because of a volcano eruption. No one seems to know why this time. You gave the http://www.globalwarmingart.com/wiki/Image:Short_Instrumental_Temperature_Record_png link which shows the Pinatubo eruption. It shows that 2005 is barely warmer than 2001, 2002, 2003, 2004, and 2006. So far, 2007 is "the fourth warmest on record for January-August year-to-date period." The average for the past seven years has been almost flat. The rate of temperature increase has been reduced in direct opposition to the theory.

When you discussed the solar cycle, you failed to note that cycle 24 has not yet begun. You also said that "we might get 0.2 C on top of CO2 warming over the next 5 years when we head toward maxima" but you did not express any confidence levels in the word might. What is the probablility of getting a 0.2 or even -0.2 temp change?

You discussed the poles saying that we expect the poles to warm faster, but failed to note that only one pole is warming and that is due to irregular wind patterns. Granted the wind information may be newer than your original post.



"Some studies even suggest we might not warm much until 2009..." Might? What is the probability? Ocean currents will be able to change how heat is distributed, not the amount of energy retained. What are the other short term natural changes? Why would you "fully expect to be warming as time goes on" when you don't seem to know what the current negative forcing is? These should be easy questions for you since "Natural variations have been extremely well studied and documented in the primary literature..."

" but we simply cannot explain it without adding the anthropogenic CO2"

This is a logical fallacy. The fact that you cannot yet explain it does not mean that anthropogenic causes are the reason. I have a Veizer quote in my http://greycanada.blogspot.com/2007/09/more-settled-science_14.html post:
"... reconstruction (via fossil shells) of tropical sea surface temperatures for that last 550 million years only made sense if carbon dioxide were not the principle driver of climate variability on a geological timescale."

"water vapor is not a climate forcing, it is a climate feedback" Any greenhouse gas can be either a forcing or a feedback. It is a forcing if its concentration changes first thus making the temperature change. It is a feedback if the temperature goes up first. When land use changes cause the air to be more arid, that is a negative forcing. When a desert is greened, then the air gets more moisture which forces the heat content of the air to increase.

Why do you bother with realclimate.org? They only present one side of the story. When there is intelligent dissent, the posts get deleted. They are not interested in a scientific discussion.

From my http://greycanada.blogspot.com/2007/06/save-us-co2.html post:
"the mean global sea level rate of rise did not trend upwards after 1950, nor has it subsequently exceeded its 1950 rate-of-rise"

How can you say that "[w]e know the troposphere and surface are warming, and stratosphere and above are cooling, in line with AGW theory (but not other natural forcings like the sun)" when that is contrary to "[s]ome studies even suggest we might not warm much until 2009?"

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#23878 - 10/16/07 09:31 PM Re: Greenland Melt Record High [Re: John M Reynolds]
Chris Offline
Junior Member

Registered: 10/05/07
Posts: 22
First, it's been fun posting here (and I appreciate the healthy discussion with Canuck and Imran) but it seems the insulting will and blog rading will begin now, and there is a deal of information already here. I'll just try to make a few final points through clarification and rounding out the discussion, without usurping the “last word.” I look forward to continuing this discussion in other areas.

First, I start with a Raymond Pierrehumbert quote:

Quote:
The forcings by the greenhouse gases have little uncertainty because their concentrations are accurately measured in the atmosphere, and their infrared absorption properties are very accurately measured in the laboratory. The two are put together using highly accurate numerical methods that have little error. The small uncertainty is primarily because the radiative forcing depends on temperature profiles (well observed), water vapor profiles (somewhat less well observed) and cloud profiles (with additional uncertainties). The water vapor and clouds come in because you get little additional radiative forcing from greenhouse gas increases below a thick cloud. Similarly, water vapor competes somewhat with absorption due to the other greenhouse gases. There is no plausible ways these uncertainties could be stretched to accomodate the scenario you are proposing.
(for context, the stretch in the original comment was forcing being off by 20%)

There is still a good deal of uncertainty in many specifics of the climate change- El nino's, aerosols, feedbacks and tipping points, clouds, biological responses, etc. In a way, evolution has the same uncertanties- exactly when and how and where did we first get humans, what was the perfect transiton between this time and that time? But I can say with near certainty you will never find a gap so good as to show me a poodle in the Permian, or a chimpanzee in Cambrian time. We still have uncertanties into the mechanics behind plate tectonics, but we know they move and what happens at various boundaries. Similarily, anthropogenic climate change, like all these things has an especially strong solid base and has grown for decades with contributions to various aspects of it (ie the proposal of a greenhouse effect) from the time of Fourier. I am extremely confident that this foundation will turn out to be fallacious, and so are the experts that matter. For a translation of Fourier's Mémoire sur les Températures du Globe Terrestre et des Espaces Planétaires see http://geosci.uchicago.edu/~rtp1/papers/Fourier1827Trans.pdf. fourier doesn't actually mention a greenhouse, or write down complex equations, or how the outgoing thermal flux increased with temperature (which today is the T^4 stefan-boltzmann law), the dynamics of convection and water vapor and CO2 or clouds, but it was a start. Fast forward a couple hundred years and we arrive at a time that is stil asking questions, and still expanding on our knowledge, but to say we know nothing is hopelessly illogical. To say we don't know enough is wrong; we know very well what happens with a given amount of CO2, how things will respond, and we most certainly have clouds in models. We know the direction we are going in, and we know the things at stake. I can't "prove" anything for future scenarios (which really isn't how science works), but give you a "highly confident" warning.

Just as a response to some points above- on the feedbacks, I think I already went over this, but the inseparable water and clouds is a falsehood. First, the cooling due to evaporation is how the surface comes back to equilibrium after being perturbed by the increased radiative heating; that is automatically accounted for in models, and is necessary for them to reach equilibrium, which is a prerequisite for an estimate of the "equilibrium climate sensitivity" to a doubling of CO2 that is always cited from the IPCC reports (i.e., 1.5-4.5 deg. C until the most recent report, now 2-4.5 is more like it). Then, it is not true that increased evaporation forms clouds and is an example of a negative feedback. Increased evaporation increases water vapor; the competition between increased water vapor and increased temperature cause relative humidity to change little as the climate warms (you need saturation to get a cloud), and it is relative humidity that determines the formation of clouds. As proof: In midlatitudes it's a lot warmer in summer than winter, and there's lots more evaporation in summer, yet if anything there are fewer clouds because relative humidity is on average lower. But Climate models now predict that cloud feedback will be either close to neutral or positive in a warmer climate.

The conclusions from the U.S. Climate Science Program are clear: "The observed patterns of change over the past 50 years cannot be explained by natural processes alone , nor by the effects of short-lived atmospheric constituents (such as aerosols and tropospheric ozone) alone." Measurements and models are still being worked on, but the IPCC and others make it clear the anthropogenic signal is certainly noticeable. '98 has been tirelesly addressed and will not be repeated- there is clearly a trend and a one-year anomaly which is irrelevant for showing how the century will warm.

I did not say we expect antarctica as a whole to be warming, and in fact in my post above I made it clear we expect quite the contrary over many areas. It is not at all established that the Arctic warming is due to natural variability alone. Even if the AO is part of the Arctic climate change, one has to face the possibility that changes in GHG's are affecting the natural change( Palmer and Molteni). the changes are large and fast, and consistent with warming. Natural variability is large in the Arctic however. Probably the best explanation from Dr. Richard Alley is that "we changed the atmosphere in ways that made warming and sea-ice loss more likely, and they happened".

The temperature trends in the atmosphere have nothing to do with Smith et al. (2007) on how ocean currents may offset some warming or Camp and Tung (2007) on the solar cycle enhancing warming for 5 years (which I am a bit skeptical of for reasons beyond this post).

Paleoclimate- while Shaviv and Veizer have been skeptics, there is still a great amount of literature on CO2 as a primary climate influence over geologic time, and I think the AR4 paleoclimate chapter will do justice to the enormous body of information, or really, just a geology or paleoclimatic textbook.
These are two that came out after the AR4 http://www.nature.com/nature/journal/v449/n7159/abs/nature06085.html (this one has co-author Veizer so apparently he thinks there is some influence) and http://www.nature.com/nature/journal/v446/n7135/abs/nature05699.html .

On realclimate- the posts there are from climate scientists generally speaking from primary literature they recently put out, or guest posts from top scientists in their areas (like Soden in the feedbacks reference or Ray Pierrehumbert on radiative transfer). Ad hominems aside, the "both sides" is becoming a bit toppled over to one side, as the scientific literature has become a bit lacking of anti-GW data, but I guess I'll go to the flat earth society to make sure we get "both sides" in the Earth shape "controversy"


I hope some people continue to go over what I've referenced, but it looks like I've worn out my welcome. I strongly suggest that people go over the IPCC report at their main page, and other primary sources, rather than the blogosphere and other wingnut articles. NASA and NOAA and Geophysical Union and NAS and the science, nature, etc journals are there for good reason-- Chris


Edited by Chris (10/16/07 09:34 PM)

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#23881 - 10/17/07 12:49 AM Re: Greenland Melt Record High [Re: Chris]
Amaranth Rose II Offline

Superstar

Registered: 12/16/06
Posts: 962
Loc: Southeast Nebraska, USA
Thanks, Chris. That got me an abstract. Any idea where one might find the entire article?
_________________________
If you don't care for reality, just wait a while; another will be along shortly. --A Rose


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#23895 - 10/17/07 11:00 AM Re: Greenland Melt Record High [Re: Amaranth Rose II]
John M Reynolds Offline
Senior Member

Registered: 08/14/06
Posts: 174
Loc: Canada
Chris. Thanks for the honesty. I understand why you are frustrated. You are using a shotgun approach to address a single topic. That is difficult to maintain. I know because I have tried it before. You brought up many areas that are worthy of discussion. Sorry for allowing myself to be lead to off topic areas.

By the way, what does AO represent?

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#23896 - 10/17/07 01:41 PM Re: Greenland Melt Record High [Re: John M Reynolds]
ImranCan Offline
Member

Registered: 09/04/07
Posts: 94
Loc: Brunei
Chris - just want to say I appreciate the info you have provided. Whilst I don't agree with all of your conclusions (particularly on your belief in modelling results - I'm with Canuck and John on this one : you get out what you put in).... your knowledge on the subject is obviously much greater than average so there is no question about having 'worn out your welcome'. I hope you contiue to remain engaged.

Cheers
Imran

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#23901 - 10/17/07 03:18 PM Re: Greenland Melt Record High [Re: Chris]
ImranCan Offline
Member

Registered: 09/04/07
Posts: 94
Loc: Brunei
Chris
The best forward looking temperature projection I could find is from the IPCC 2001 report. On page 34 of the "summary for policy makers" report is a graph which has a range of projection scenarios of "modelled" temepratures into the future. Quite correctly it gives a range of projections into the future. The RANGE for the current time frame (end 2007) was PREDICTED between 0.50 degrees and 0.68 degrees above the 61-90 average - numbers I have approximately read off the graph. Note that the graph relates the data to the 1990 value so you have to translate the numbers to the 61-90 average (approx 0.18 degree translation)

However, The ACTUAL 2007 global mean temperature (smoothed, ie. rollig average) is only about 0.44 degree above the 61-90 mean. See below the UK dataset which is also closely represented in the IPCC 2007 report.

http://hadobs.metoffice.com/hadcrut3/diagnostics/global/nh%2Bsh/index.html

Clearly this is well below the range predicted at the time of the 2001 IPCC report. This is why I am so firmly aligned with the likes of Canuck on my 'distrust' of models. In a short period of 6 years, the reality has been shown to be significantly outside the total range of scenario projections given by the IPCC 2001 report. Its easy to model the existing datasets and say the only way to match is to utilise a significant AGW component. But there also needs to be accountability looking backwards at previous projections - otherwise the models very quickly lose credibility. There is no way in a 6 year period the models should be so far outside the range.

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#24323 - 11/18/07 04:29 AM Re: Greenland Melt Record High [Re: ImranCan]
ImranCan Offline
Member

Registered: 09/04/07
Posts: 94
Loc: Brunei
Originally Posted By: ImranCan
Interesting reading. What I would like to know is why there is such localised warming in the Arctic when the overall global mean surface temperature has been static for nearly 10 years ??

My feeling is that this can only occur due to ocean current shifts such as a more northerly route for the Gulf Stream. Any views on this ?



A while ago I wrote this based on nothing more than an application of common sense .... but didn't have any evidence to support it .... yesterday I picked up a news report about a study which confirmed this ..... but I can't find the actual study ... does anyone have this or can send a link ... ?

http://www.foxnews.com/story/0,2933,311884,00.html


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#24326 - 11/19/07 02:43 AM Re: Greenland Melt Record High [Re: ImranCan]
John M Reynolds Offline
Senior Member

Registered: 08/14/06
Posts: 174
Loc: Canada

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#24575 - 01/17/08 02:58 AM Re: Greenland Melt Record High [Re: John M Reynolds]
Mike Kremer Offline

Megastar

Registered: 10/16/04
Posts: 1696
Loc: London UK
Originally Posted By: John M Reynolds
http://www.jpl.nasa.gov/news/news.cfm?release=2007-131


[quote=Mike Kremer] 2 John M Reynolds

Those circulation reversals are v interesting, but strange?
Heres a newer Greenland posting (inserted at last posting date)

http://www.physorg.com/news116593011.html

_________________________
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"You will never find a real Human being - Even in a mirror." ....Mike Kremer.



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#24652 - 01/23/08 07:27 AM Re: Greenland Melt Record High [Re: Mike Kremer]
JonathanLowe Offline
Member

Registered: 10/29/06
Posts: 87
Loc: Melbourne
but still the total global ice levels are above or the same as normal. There has been no decreasing or increasing trend in global sea ice in the last 30 years. See the bottom graph on this link:

http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/global.daily.ice.area.withtrend.jpg

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#24851 - 02/13/08 04:27 PM Re: Greenland Melt Record High [Re: JonathanLowe]
Mike Kremer Offline

Megastar

Registered: 10/16/04
Posts: 1696
Loc: London UK
Originally Posted By: JonathanLowe
but still the total global ice levels are above or the same as normal...................>


Originally Posted By: Mike Kremer

Oh well.....back to the original subject "Greenland Melt Record High".
Prehaps I ought to mention, for the benefit of our newer readers, that JonathanLowe is one of our Scienceagogo members who most adamantly does, not believe in global warming, at least not according to his previous postings here and elswhere.

So here is a short entry by:-
Marco Tedesco, a research scientist at NASA’s Goddard Space Flight Center.
He said that at altitudes above 2,000 meters in Greenland – a little over a mile high – snow melted for up to 30 days longer than the 20-year average.

Marco Tedesco: This is about 150 percent greater than the previous average.
Data from satellites indicated surface temperatures over the Greenland ice sheet were up to four to six degrees Celsius above average in 2007. And as Greenland melts, sea levels continue to rise.


http://www.earthsky.org/radioshows/52193/record-high-melt-in-greenland-high-places-in-2007#



_________________________
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"You will never find a real Human being - Even in a mirror." ....Mike Kremer.



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#24875 - 02/15/08 03:55 PM Re: Greenland Melt Record High [Re: Mike Kremer]
ImranCan Offline
Member

Registered: 09/04/07
Posts: 94
Loc: Brunei


Originally Posted By: Mike Kremer

So here is a short entry by:-
Marco Tedesco, a research scientist at NASA’s Goddard Space Flight Center.
He said that at altitudes above 2,000 meters in Greenland – a little over a mile high – snow melted for up to 30 days longer than the 20-year average.

Marco Tedesco: This is about 150 percent greater than the previous average.
Data from satellites indicated surface temperatures over the Greenland ice sheet were up to four to six degrees Celsius above average in 2007. And as Greenland melts, sea levels continue to rise.


Seeing as we are back to the orginal discussion point in the post .... heres an alternative view of this report ...

http://www.worldclimatereport.com/index....land-melt-area/

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#25272 - 04/02/08 02:42 AM Re: Greenland Melt Record High [Re: ImranCan]
JonathanLowe Offline
Member

Registered: 10/29/06
Posts: 87
Loc: Melbourne
so global warming is only effecting Greenland whilst the antarctic increases to near record ice levels, and the arctic is recovering with almost back to normal records, and the world in total has heaps of ice, over 1 million square kilometers of ice than normal.

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#25296 - 04/04/08 12:01 AM Re: Greenland Melt Record High [Re: JonathanLowe]
Mike Kremer Offline

Megastar

Registered: 10/16/04
Posts: 1696
Loc: London UK
Originally Posted By: JonathanLowe
so global warming is only effecting Greenland whilst the antarctic increases to near record ice levels, and the arctic is recovering with almost back to normal records, and the world in total has heaps of ice, over 1 million square kilometers of ice than normal.


Originally Posted By: Mike Kremer

Yes, yes, its all very well quoting an individual Graph here, or of increased ice coverage there etc.
Individual measurements are an essential part of weather reporting. Computers can help detect trends.
But to date there is no computer powerful enough to process those tens of thousands of moving readings, that need to be fed in on a daily basis. So that it can ultimately 'spit out' an averaged overall contribution of all inputs, to show us a future weather trend.

I'm afraid that the trend for Climate Warming is still upwards.

_________________________
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"You will never find a real Human being - Even in a mirror." ....Mike Kremer.



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#25305 - 04/04/08 03:42 PM Re: Greenland Melt Record High [Re: Chris]
RicS Offline
Senior Member

Registered: 03/26/06
Posts: 310
Loc: Sydney, Australia
G'day,

Hate to burst any bubbles, but the THEORY as to the drop in temperatures in the British Isles is related to what went on in North America, not to actually to any ice sheets in water even connected to it.

The last glaciation ended around 11,300 years ago but that didn't mean that all the ice melted. Far from it. Actually, a animated movie got it sort of right. Ice Age II showed a huge cliff face of ice that suddenly broke.

For various reasons, North America had a ice pack that, at the end of the last glaciation, abruply stopped. In places it was over a mile or two kilometres high and it covered a pretty large section of North America just to the south of the Canadian border and upwards.

So the glaciation ends. The world warms up. The conveyor keeps UK Isles comfy warm and certainly warmer than Europe. Ice retreats throughout the Northern Hemisphere and melts across the US and Canada. But an ice sheet over a mile (1.6 km) thick doesn't just melt overnight. And this wasn't really a glacier because it extended in a sheet like form over many hundreds of miles east to west. What did happen to it was it evaporated and started to form rivers running most to the east. But you still had this pesky problem of a cliff face of ice extending accross north America from the Atlantic well into the Mid-West. That section didn't melt so fast and very quickly formed a massive dam, preventing meltwater running north to south.

So a huge lake formed on top of the ice, reducing the Albedo of the region from very high to very low, thus not slowing down the process of the transition from glaciation to interglacial period. Had it remained as a frozen region it would have been so large that the transition to interglacial period would have been very difficult indeed to sustain.

And it sounds very strange having a lake above ice but this ice had been sitting in one spot for a very long time, was very packed together and simply could not pop like a cork. Instead the ice under this lake melted quickly and the lake became one with ground at the bottom rather than ice. The pressure was staggering and eventually the wall of this superlake started to collapse at the point where a river had already been letting out vast quantities of water. It is thought that the lake collapsed and emptied into the Altantic in one massive mega event, the collapsed Atlantic wall started at the US/Canada border.

The very very cold, very low mineral content water spread out into the Atlantic in three dimensions and the best guess that I have seen is that it caused a disruption to the glaciation/integlacial transition by some 800 years, with parts of the world returning to glaciation like temperatures and parts remaining as they had been for only a relatively short amount of time.

While spectacular it might have been and facsinating in that the evidence of this disruption to the transmition throws up a lot that supports the theories that transitions between interglacial and glacial periods is very short indeed, it did not cause an "ice age" of any type, nor did it trigger a glacial period. It just stuffed up the pattern of climate for parts of Europe and certainly North America. What it did do was free North America from ice coverage probably much faster than if it had just receded because of the warming. It was an odd event and so might have had something to do with assisting the mass extinctions of mega fauna in North America (although I think the Clovis people managed to do that pretty much all themselves before they finally managed to became a little attuned to the eco system).

It also seems to demonstrate that once a flip occurs towards an interglacial period or a glaciation, it is darn hard to reverse it once beyond some critical point.

Actually it is a fascinating subject very much lacking in appropriate studies. Since it was such a massive event for North America, happened only 10,500 years ago or thereabouts and the US has the resources, one would think that it would be the subject of endless study. The trouble is, imho, is that it does nothing whatsover to support global warming theories and indeed could be used in the argument to suggest many of the global warming theories might be faulty, and thus isn't much mentioned.


Regards


Richard
_________________________
Sane=fits in. Unreasonable=world needs to fit to him. All Progress requires unreasonableness

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#25306 - 04/04/08 04:40 PM Re: Greenland Melt Record High [Re: Chris]
RicS Offline
Senior Member

Registered: 03/26/06
Posts: 310
Loc: Sydney, Australia
G'day Chris,

Hmm, the el Nino 1998 being "weird". Not a word I would use. And 2005 being a record, huh. Sorry. Don't agree at all. What dataset are you looking at. Going by the 1979 to date Surface Air Temperature and low altitude air temperature averages from the two satellites tasked to gather such data, 1998 was truly a very large el Nino affected year, but 2005 was not even close to being a record. It too had significant el Nino effects aiding any increase.

So we have 1998, probably a one in a century event because of factors that contributed to making the el Nino the largest effect it could be on climate for the year. That sort of data, in datasets that are not extensive enough are normally excluded to prevent distortion due to a one off. If I was studying the breeding cycles of tree frogs and had ten years of data but in one of the years an outbreak of some disease killed most of the rampaging cats in the area where the study was being done, I would have to either exclude that year, wait another twenty years or so until my dataset was actually of a reasonable period or mark up the data summaries very heavily with a warning concerning that particular year. It might not be the best of analogies but since it happens to be one that actually happened, and my brain isn't functioning more than it's 10%, it will have to do.

I do not believe that 1998 should be included in any datasets when arguing average world temperatures simply because the datasets are not extensive enough to show any cycles of this type of rare occurence. It is somewhat like those stupid statistics for dam constructions where they indicate it will survive anything but a 1:10,000 year flood. How could anyone have any idea what the rainfall pattern or amount is over a period of 10,000 years since in most cases of dams the records go back perhaps 50 years and even then usually not for the exact area of the dam.

In a dataset that goes from 1979 to 2007, even a 30 year cycle event may not show up, let along a 100 year cycle, and of course climate does not just have cyclical events but random events that have average frequencies between events only. A one in a hundred year event, for climate, does not mean that it happens once every hundred years, only that it happens, on average, one time for a hundred years where it doesn't happen. That doesn't mean that it doesn't actually happen three times in ten years and then none at all for several hundred years.

The AVERAGE for this Ice Age for Interglacial periods is that they will only last for 10% of the time for the Ice Age and should be ON AVERAGE 5,000 years or less long before again reverting to a glacial period. Using those figures this glaciation is 6,000 years overdue to return to an Interglacial Period and thus the odds are far higher that the Interglacial period will end in the short term than not. That is not true of course, just as the odds of throwing a heads is the same after thowing ten heads in a row or after thowing ten tails. Human brains are not wired to recognise this as true because pattern recognition is so hardwired into our head. Does not make it incorrect though, just difficult to grasp.

By the way even if you INCLUDE 1998 in the satellite data you still do not get any significant warming trend and extruding it you actually get a cooling trend, although too slight to argue anything.

The surface air temperature data from ground stations does indeed show a large increase in average temperatures from about 1975. Suspicion should fall on any data where the most accurate method of collecting the data, seriously contradicts that data, yet the SAT ground collection data seems to be used as if it is accurate to several decimal places. Trouble is the data is grossly inaccurate, the collection system is seriously flawed, the averaging system is whatever the relevant authority for an authority decides it to be and can and has been changed over very wide areas on a whim. Measuring devices are changed. The positioning of the equipment itself is changed. Minor little things such as urban heat effects are ignored or somehow are written off as too minor to be worthy of adjustment (although an error in the satellite system that could have meant the averages were out in the order of 10,000th of a percent have been argued by a great many as reason enough to consider the satellite data to be fundamentally flawed).

So if we use the North American climate dataset for continental US, we find that not only has the rather more than insignificant chunk of the earth has not warmed over the past century, it has actually cooled a bit. It has not warmed significantly from 1975 on.

If we us the British Admiratly records of Surface Air Tempertures at sea over the last 200 years we also find that no significant warming trend has occurred and that only a pretty minor warming trend is shown from 1975.

The satellite data from 1979 shows no warming with the 1998 data, slight cooling without it.

Oh and Chris, the dataset you used is partly modelled and very much based on assumed data and assumed corrections to the data that is available. It takes a long time to do it but have a look at the raw data without corrections for things that are assumed to need correction for, as I have actually done, and you don't end up with a graph even remotely like the one you posted.

When looking at AVERAGE world's temperatures, the field becomes immensely complicated. It shouldn't be because we have a pretty good dataset from 1979 onwards. It just gets ignored because it does not provide the nice rising graph that seems to be wanted. Most people would agree that you really should compare apples with apples. That data used should be sourced the same way, using the same methods, the same calibration to equipment, the same positioning if it has some importance, the same mathematics to summarise the data, etc, etc.

So you can rely on the UK Admiratly Figures for water temperatures for the last 200 years becaus the method has not changed much. It cannot ever be fully comparable because the measuring tools have been updated and not calibrated against the equipment being retired or against some standard. You also have the problems that the ships were not in the same position each year and that some years concentrations occurred in say latitudes or particular oceans etc. And the problem of increased ability to travel in difficult sea areas such as areas subject to severe weather or very cold areas or areas with icebergs also disturbs the distribution of collection points. However, at least some of the methodology was consistent.

You can rely on the US weather collection for small towns of less than 5,000 population where the weather stations have not moved over the last 100 years if you want relatively comparable figures without the problem of massive changes because of heat islands etc. But this is a very small dataset indeed because there are very few stations even in the US where such things as wars and civil uprest have not had an impact.

You can rely on Australian weather collection in the same categories as that above and pretty much for the same reasons and with the added bonus that weather stations have been moved less often than their US cousins.

NZ weather data is even more comparable.

As mentioned before you have the world's satellite data for not only temperature but also for ice coverage, at least two dimensionally, from 1979.

And that's about all.

It is amazing just how non comparable weather data collected around the world for whatever reason has been. The US may have at least the plus of not having been interupted by wars or civil unrest and the like. But there has been seven changes in the times of temperature collection in the past century, to give just one example of the hundreds of reasons why the data is just not camparable. You just cannot rely upon a figure in the records that says Springfield had a temperature of 38.7 degrees in 19 July 1919, a record high. That's a bit like saying your body temperature is exactly 98.4 degrees because that is what it should be when not sick. I've been in enough hospitals to know that variations as much as half a degree out can occur simply because of different themometers used. And that excludes different methods of collection. If one side of my mouth can give off a temperature reading 0.3 degrees different to the other side using the same themometer and being only several seconds apart in the measurements then just how far out could readings be when measuring devices are moved 100 metres up hill, or from the shade at the side of a building to full sunlight.

And any argument that is along the lines that all these variations cancel out really hasn't thought the comment through.

If the prior data is that unreliable, I find real problems with comments such as "studies show" and then suggesting that something might happen to the temperature in 2009 or at any other time because that is not a study at all but a guess based on a model. Compounding the problem is when such comments are linked to what CO2 might do in the future and how this is somehow linked to the future temperature.

If the link between the small fraction of CO2 in the atmosphere varying and temperature varying because of it is in any way true, please point out any study that demonstrates the link in any way at all.

This is a particularly difficult area in relation to climate change, but actually the most important aspect. To argue that the world is warming actually requires that one knows what the world's temperature is and was. If that is not known then the change must be very significant indeed so that anecdotal evidence is overwhelming, or you just cannot establish warming (or cooling for that matter) at all.


Regards


Richard

_________________________
Sane=fits in. Unreasonable=world needs to fit to him. All Progress requires unreasonableness

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#25333 - 04/06/08 01:51 PM Re: Greenland Melt Record High [Re: RicS]
ImranCan Offline
Member

Registered: 09/04/07
Posts: 94
Loc: Brunei
Originally Posted By: RicS
Going by the 1979 to date Surface Air Temperature and low altitude air temperature averages from the two satellites tasked to gather such data, 1998 was truly a very large el Nino affected year, but 2005 was not even close to being a record. It too had significant el Nino effects aiding any increase.


Ric
Do you have alink to the data you are refrrign to here. Like you (and as per your other recent posts) I'm more and more convinced that the only reasonable data to use for global temperature comparisons is satellite data for sea surface measure ments.The more I look intio any land based measurements, the more perturbed I am becoming.

Thanks
Imran

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#25334 - 04/06/08 04:33 PM Re: Greenland Melt Record High [Re: ImranCan]
RicS Offline
Senior Member

Registered: 03/26/06
Posts: 310
Loc: Sydney, Australia
G'day,

Because of my medical condition, I cannot get at any of my papers. This means that I cannot provide references. I'm very sorry because they often very important. The datasets for surface air temperatures are pretty easy to find. Try the University of Hunstville site for satellite data sets. They are published on the web so they are not all that difficult to find.

I'd do the search myself but I can't read the screen very well. My condition requires that I do not move out of a particular plain of position and even slight movements such as so I can use my notebook leads to bad vision, horrible headaches and nausea that you wouldn't wish on your worst enemy. Sigh. The condition is actually fascinating if you are interested in higher brain function and how seriously it can be affected by the change in CSF (cerebral spinal fluid) pressure or the manufacture of too much of the stuff. It attacks parts of the brain fairly randomly and can even lead to problems in deciding if what you see is real or imagined. For those that have any interest in such things, this can be caused by all manner of injuries or illnesses. Mine is caused by a leak where a catheter goes into my spinal column, a leak made dramatically worse by a fall, aparently causing the catheter to move and "break the seal". Thus far, it has no hope of being fixed because of the degree of scaring around it.

Way off track but provided because many times previously when I have been here I have been accussed of not providing appropriate references. In those prior instances, when I did provide references, they were then maligned and attacked, so I stopped providing them then eventually stopped posting at all. Thankfully the site seems to have returned to a pleasant place to post divergent opinion without personal attacks but now that I can post expecting responses that are polite and interesting, I'm stuck in a position where I cannot be as useful as I would like.

In future posts, where I recall anything that will aid in finding the reference, I will provide it in a PS at the end of the post. I hope that is of some benefit.


Regards


Richard
_________________________
Sane=fits in. Unreasonable=world needs to fit to him. All Progress requires unreasonableness

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#25335 - 04/06/08 04:38 PM Re: Greenland Melt Record High [Re: RicS]
RicS Offline
Senior Member

Registered: 03/26/06
Posts: 310
Loc: Sydney, Australia
G'day again ImranCan,

Oh, you might find it quite difficult to find the UK Admiralty records. They are generally referred to as water surface temperature records but also include air temperatures taken at the same time. The beauty of this dataset is that the method used in the collection of data is consistent over time and the record keeping is likely to be very accurate. I know of no place on the Internet where this data is available. There are summaries available. I have the full dataset but had to get it manually.


Regards


Richard
_________________________
Sane=fits in. Unreasonable=world needs to fit to him. All Progress requires unreasonableness

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