Just what is the correct global temperature trend?

[millennia]

The debate in the thread The Great Global Warming Debate (continued) appears to be constantly sucked into a circular argument as to whether the planet is actually warming since 1998 or not. This stifles any other discussion that attempts to start up and it seems strange to me that this basic point should turn out to be such a point of contention when you consider that the temperature trend graphs should simply be a representation of the surface station data present in graph form for us all to see. Simple huh? Unfortunately as with everything else with climate change this is never the case. It appears that the RAW data is far too dirty to be let out in public and needs a wash and brush up before being presented to its expectant public. To demonstrate this a series of graphs appears below that shows only too clearly what a dilemma we are in trying to resolve the basics of climate change, or whether it is actually changing at all:

This graph is from the UK Meteorological Office's Hadley Center for Climate Studies Had-Crut data as of April 13th 2008. Although a clear warming trend from the start of the Industrial Revolution can be seen, and I think is not disputed by any side in the debate, you can see from this where the argument comes from for no warming since 1998 and the appearance of a rolling over similar to the 1940s prior to the 3rd quarter cooling event of the 20th Century.

This graph is of the NASA data as of April 13th 2008, and shows significant warming in the last quarter of the 20th Century and beyond and even puts 2005 as warmer than 1998 (which is actually the first time I've seen this so appears to have changed again from a previous position of stating it was the second warmest since 1998). So you can see why those who state the warming strend has not stopped get so frustrated when it is stated it has.

To add to this we can also insert the UAH and RSS satellite anomaly records from 1998:

So there is a good basis for confusion here, but why? Well it appears NASA are continually reworking their data and the result of this is that graphs based on the same station data look significantly different over the years. Here are the temperatures for the United States, as produced in 1999:

and 2007:

Pretty different, yes? But why would they be making changes like this? Well if you have a look at the NASA site then there are some clues, NASA staff have done some recent bookkeeping and "refined" the data from 1930-1999.

NASA and Had-Crut data are largely based on surface measurements, using thermometers. They both face a lot of difficulties due to contaminated data caused by urban heating effects, disproportionate concentration of thermometers in urban areas, changes in thermometer types over time, changes in station locations, loss of stations, changes in the time of day when thermometers are read, and yet more factors.

NASA has a very small number of long-term stations in the Arctic, and even fewer in Africa and South America. The data has been systematically adjusted upwards in recent years - as can be seen in this graph, reproduced below. Temperatures from the years 1990 to present have more than one-half degree Fahrenheit artificially added on to them - which may account for most of the upwards trend in the NASA temperature set.

This shows how what you would consider to be solid data from surface stations is modified and remodified before it is presented, meaning the layman can never have any real idea where the truth lies anymore than sticking a finger in the air and guessing.

If we can't even agree how to present the data, how will we EVER agree how to act upon it?

[MAF]

a very interesting read can be found here too http://news.bbc.co.uk/1/hi/sci/tech/7376301.stm

not sure it answers your questions. but certainly poses a few too B)

[millennia]

a very interesting read can be found here too http://news.bbc.co.uk/1/hi/sci/tech/7376301.stm

not sure it answers your questions. but certainly poses a few too B)

Just add it to the mix of confusing data - their "observed temperatures" seem to be similar to the NASA data, but their models diverge wildly at 1995 - therefore just because their predicted flat spot from 2005 to 2010 matches the observed line from 2005 to date it doesn't give you much confidence on their prediction after 2010.

[johnholmes]

yes, pretty muddy waters, even for supposed actual data

[Thundery wintry showers]

As a PhD student at UEA I tend to rely upon mainly the HadCRU outputs, and I also look at NOAA's stuff as they publish it monthly on the internet, as a general rule I find NOAA's data to be much closer to CRU's than NASA's. I'm not sure why this is, maybe NASA use completely different methodology?

Anyway, I don't think the circular discussion is really about whether or not we've warmed in the last 10 years, but is more about whether or not that 'proves' that the warming has stalled and therefore we won't have AGW. Looking at the HadCRU graph that could still be shown up as a blip in years to come, it's not conclusive, although it is the biggest stall so far since the recent warming trend started around 1975. (I will mention, btw, that discussion in that other thread ironically seems to have improved over recent days as someone posted up an interesting graph for discussion)

What this cooling does mean is that if AGW is a major issue but its effects are being delayed due to natural variability offsetting the warming for the time being, it 'buys' us more time to do something about it before the warming gets serious. Or if AGW is being overstated, then it means what we really need to be worrying about is finite availability of resources; either way, a suggestion that we don't need to rush in with sudden, draconian measures that could well cripple the Western world as we know it, and can afford to bring in change at a realistic rate. So the "we can't do anything, we're past the point of no return" idea is looking a lot more over-pessimistic, perhaps, than it did 5-10 years ago.

[VillagePlank]

What this cooling does mean is that if AGW is a major issue but its effects are being delayed due to natural variability offsetting the warming for the time being, it 'buys' us more time to do something about it before the warming gets serious.

Surely - it further means that, if the CO2 hypothesis is true, then, suprisingly, relatively benign natural factors can have an exaggerated influence on the observed temperature. That is what is happening, is it?

[Chris Knight]

The debate in the thread The Great Global Warming Debate (continued) appears to be constantly sucked into a circular argument as to whether the planet is actually warming since 1998 or not. This stifles any other discussion that attempts to start up and it seems strange to me that this basic point should turn out to be such a point of contention when you consider that the temperature trend graphs should simply be a representation of the surface station data present in graph form for us all to see. Simple huh? Unfortunately as with everything else with climate change this is never the case. It appears that the RAW data is far too dirty to be let out in public and needs a wash and brush up before being presented to its expectant public. To demonstrate this a series of graphs appears below that shows only too clearly what a dilemma we are in trying to resolve the basics of climate change, or whether it is actually changing at all:

This graph is from the UK Meteorological Office's Hadley Center for Climate Studies Had-Crut data as of April 13th 2008. Although a clear warming trend from the start of the Industrial Revolution can be seen, and I think is not disputed by any side in the debate, you can see from this where the argument comes from for no warming since 1998 and the appearance of a rolling over similar to the 1940s prior to the 3rd quarter cooling event of the 20th Century.

This graph is of the NASA data as of April 13th 2008, and shows significant warming in the last quarter of the 20th Century and beyond and even puts 2005 as warmer than 1998 (which is actually the first time I've seen this so appears to have changed again from a previous position of stating it was the second warmest since 1998). So you can see why those who state the warming strend has not stopped get so frustrated when it is stated it has.

To add to this we can also insert the UAH and RSS satellite anomaly records from 1998:

So there is a good basis for confusion here, but why? Well it appears NASA are continually reworking their data and the result of this is that graphs based on the same station data look significantly different over the years. Here are the temperatures for the United States, as produced in 1999:

and 2007:

Pretty different, yes? But why would they be making changes like this? Well if you have a look at the NASA site then there are some clues, NASA staff have done some recent bookkeeping and "refined" the data from 1930-1999.

NASA and Had-Crut data are largely based on surface measurements, using thermometers. They both face a lot of difficulties due to contaminated data caused by urban heating effects, disproportionate concentration of thermometers in urban areas, changes in thermometer types over time, changes in station locations, loss of stations, changes in the time of day when thermometers are read, and yet more factors.

NASA has a very small number of long-term stations in the Arctic, and even fewer in Africa and South America. The data has been systematically adjusted upwards in recent years - as can be seen in this graph, reproduced below. Temperatures from the years 1990 to present have more than one-half degree Fahrenheit artificially added on to them - which may account for most of the upwards trend in the NASA temperature set.

This shows how what you would consider to be solid data from surface stations is modified and remodified before it is presented, meaning the layman can never have any real idea where the truth lies anymore than sticking a finger in the air and guessing.

If we can't even agree how to present the data, how will we EVER agree how to act upon it?

Somebody is lying. Why?

[stewfox]

What this cooling does mean is that if AGW is a major issue but its effects are being delayed due to natural variability offsetting the warming for the time being, it 'buys' us more time to do something about it before the warming gets serious. Or if AGW is being overstated, then it means what we really need to be worrying about is finite availability of resources; either way, a suggestion that we don't need to rush in with sudden, draconian measures that could well cripple the Western world as we know it, and can afford to bring in change at a realistic rate. So the "we can't do anything, we're past the point of no return" idea is looking a lot more over-pessimistic, perhaps, than it did 5-10 years ago.

Could background factors being putting a lid on a pressure cooker

Once their gone the lid goes and we get an explosion (run away global warming)

Its a tough call, certainly the media will quiten down next 10yrs if global temps remain flat

[johnholmes]

Somebody is lying. Why?

that is too strong a word and most probably untrue but it does beg the question which centre is giving the most realistic picture and why there seem to be so many 'actual' charts for the same period.

Its a shame they cannot get together and decide which one to use for their arguments or which combination that they can all agree on.

At least then we would have the same base line of historical data to use for anyone to then try and predict what may happen and why.

Edited May 6, 2008 by johnholmes

[The PIT]

Well I did hear that the person in charge of the editing of the earlier temp records happens to be heavily involved with Al Gore. Now that could be a case of 2 + 2 = 5 but it certainly suggests that the data is being altered to their interests. It also suggests that this whole warming debate is now in the hands of the Politicians and extra warmth will be found whatever happens. More worrying as industries grow around the idea of being "Green" they will also lobby Politicians and unless you find warmth it's going to hard to get funding for your research.

It now looks like there's too much money involved in this and this is preventing getting to the real facts.

If it doesn't warm in the next 10 years or so watch out for the ice age cometh predictions again.

Edited May 6, 2008 by The PIT

[Bobby]

Well I did hear that the person in charge of the editing of the earlier temp records happens to be heavily involved with Al Gore

That is low...

Why do people have to bring politics into it all the time? The science is the science - it's right or it's not, whether it's Al Gore or Adolf Hitler or me doing it.

[laserguy]

That is low...

Why do people have to bring politics into it all the time? The science is the science - it's right or it's not, whether it's Al Gore or Adolf Hitler or me doing it.

Because for me at least,politics is what it's all about. The science? What science,it's so all over the place and open to however one wants to interpret it, it's meaningless.

[Thundery wintry showers]

1. Some science is uncertain, that doesn't mean all science is.

2. "Uncertain" does not mean "meaningless". If my confidence in something being true is less than 100% it doesn't make it automatically 0%.

[Richie V]

Well I did hear that the person in charge of the editing of the earlier temp records happens to be heavily involved with Al Gore. Now that could be a case of 2 + 2 = 5 but it certainly suggests that the data is being altered to their interests. It also suggests that this whole warming debate is now in the hands of the Politicians and extra warmth will be found whatever happens. More worrying as industries grow around the idea of being "Green" they will also lobby Politicians and unless you find warmth it's going to hard to get funding for your research.

It now looks like there's too much money involved in this and this is preventing getting to the real facts.

If it doesn't warm in the next 10 years or so watch out for the ice age cometh predictions again.

I hate to say this but............. I totally agree with you pit. IF there is truith in that "extra warmth" is been falsley added to keep up funding, surley sooner or later it will all end in tears!

[johnholmes]

the sad part about it is this the earth IS warming, IF it does continue, even after a decade of slowdown, IF, it is almost certain to carry on warming.

IF it does then sooner or later it will reach the point at which ice melts off the CONTINENTS NOT over water. That is when sea levels will rise. By then it will be too late to create an action plan for the millions to be displaced by sea levels inundating their areas. The seeds of distrust are being sown by politicians and commercial organisations looking to make money. Sad that pure research, which is what is was at first, has gone this way.

I can now see one advantage for my advanced age at least I'll not be around to see it, sadly the grandchildren of my grandchildren probably will and the chaos that will follow.

Edited May 6, 2008 by johnholmes

[Bobby]

But politics doesn't invalidate the truth of the science. What is correct is correct, end of.

[SnowBear]

But how do we know what is the truth and correct when politics and economics gets involved as with a lot of research into climate change?

Also so many conflicting reports, data, some research backed by this group, some by that, some ignore certain parts, others dont, trust by some in one thing, others dont.......whole thing is a right old fiasco.

I am beginning to realise that seeing the real truth is like trying to see a clear image of a skipjack tunu which is 1 mile away, in murky muddy sea water with welding glasses on.

No-body seems to really have a clue what is going on.

[The PIT]

But politics doesn't invalidate the truth of the science. What is correct is correct, end of.

It does if it's effects the results therefore what is produced is isn't correct. Since yourself (possible) myself (certainly) and many others on here aren't qualified in the fields concerned and neither have access to the orginal results and testing we cannot say it's 100% correct or has been influcenced by other factors. End off.

Overall a Niave view Magpie. I don't really believe that you can be spoon fed scientific "facts" you come across generally far too intelligent for that. I guess it was a rapid post done without due consideration.

Edited May 7, 2008 by The PIT

[Devonian]

I simply don't understand this kind of thread.

Would it matter if some point in the time scale world population was measued by one organisation 6.3 and another 6.5 bn? Not at all. Would it be absurd to suggest wrongdoing or worse over the differences? It would - such differences don't matter, they're simply the errors involved in such measurements.

What matters is the trend and that the measurements are accurate enough to draw conclusions - this thread is just a distraction from that, and in some cases a politically based distraction.

We all know it's warmed, and most of us accept the why of it. There is debate over the degree of future warming - lets talk about that.

Edited May 7, 2008 by Devonian

[VillagePlank]

I simply don't understand this kind of thread.

Would it matter if some point in the time scale world population was measued by one organisation 6.3 and another 6.5 bn? Not at all. Would it be absurd to suggest wrongdoing or worse over the differences? It would - such differences don't matter, they're simply the errors involved in such measurements.

What matters is the trend and that the measurements are accurate enough to draw conclusions - this thread is just a distraction from that, and in some cases a politically based distraction.

We all know it's warmed, and most of us accept the why of it. There is debate over the degree of future warming - lets talk about that.

OK let's talk about trends. What do you know about trends? Shall we start with a non-linear mapping mth degree polynomial curve?

EDIT: Forget this, I'll write a quick piece and post it later.

Edited May 7, 2008 by VillagePlank

[Devonian]

OK let's talk about trends. What do you know about trends?

If I'm honest, not much of the maths involved. But, I do trust those at the Met O or NOAA to do an honest job - rather than just push the disrespect and suspicion button or even the 'L' button like some here do

Shall we start with a non-linear mapping mth degree polynomial curve?

Oh, yes, more your field than mine, probably by a lot tbh - like I say I don't do the maths. I wont treat you with the disrespect and suspicion like others here treat other experts - like climate experts....

EDIT: Forget this, I'll write a quick piece and post it later.

I look forward to it

Edited May 7, 2008 by Devonian

[The PIT]

I simply don't understand this kind of thread.

Would it matter if some point in the time scale world population was measued by one organisation 6.3 and another 6.5 bn? Not at all. Would it be absurd to suggest wrongdoing or worse over the differences? It would - such differences don't matter, they're simply the errors involved in such measurements.

What matters is the trend and that the measurements are accurate enough to draw conclusions - this thread is just a distraction from that, and in some cases a politically based distraction.

We all know it's warmed, and most of us accept the why of it. There is debate over the degree of future warming - lets talk about that.

So if the trend is wrong due to data being altered it means a vastly reduced input by man. It also means if data is being altered a lot of it is void.

As far as you know this maybe a 100% natural warming cycle. Not very hard too understand really.

Edited May 7, 2008 by The PIT

[Essan]

What is the correct global temperature trend?

On a centennial basis the trend is very clearly up according to all currently available data.

On a millennial basis it's a little more complicated as there appears to have been a downward trend for the past 4-5 thousand years, although recent temps do seem to have - temporarily at least - reversed that.

On any smaller time scales it's totally meaningless

(Of course this varies from region to region making a true global assessment complicated and subject to debate)

As far as you know this maybe a 100% natural warming cycle. Not very hard too understand really.

It can only be 100% natural if no human activity whatsoever has any effect on temperature anywhere in the world

So are UHIs natural or manmade? If the latter, then some AGW must exist, whatever else you believe

(GW means an average of all temps around the world - if some areas, however small, are warmer due to human activity then there is an anthropogenic component to the temp)

[J07]

But politics doesn't invalidate the truth of the science. What is correct is correct, end of.

I think that's oversimplifying things. Science is full of politics itself, it's inescapable. It used to amaze me how often I found scientific papers claiming one thing when just a little critical reading blows wide open the fact that they hadn't calculated errors on their data, and when you do it yourself you find their results are close to worthless. Yet still they make firm conclusions. Why? Well, I guess they want their funding to continue. Reputation. Earning a crust. It's the same in science as in the rest of the human world.

The problem is that "not all papers are created equal". It may be (and probably is) the case that most papers are pretty upfront about what they have found, however, it only takes 1 in 50 to get noticed by the media, and then everyone is in trouble. Because once the general public get their hands on scientific results through tabloids and mainstream information sources, all sorts of bad things happen and the public are fooled into thinking that this is a scientific consensus, when really there are 49 other papers out there lambasting the rogue scientist and all their data and not getting heard at all.

[The PIT]

It can only be 100% natural if no human activity whatsoever has any effect on temperature anywhere in the world

So are UHIs natural or manmade? If the latter, then some AGW must exist, whatever else you believe

(GW means an average of all temps around the world - if some areas, however small, are warmer due to human activity then there is an anthropogenic component to the temp)

However if data is being altered how can you find out what the human input is???

By the way I'm not saying there isn't but a lot of the so called factual data is getting more and more suspect as time goes on.