New Iceage? Much Evidence? - Global Cooling

[pottyprof]

you can't dismiss the heat rise associated with towns and cities as an inaccuracy, as it's real and a reflection of what's happening across the planet as the population grows.

Agreed. What I'd like to know (and I don't know if anyone has checked this out), is how far into the atmosphere does this effect go? We all know the effect of concrete, tarmac and the like for storing up the heat but is it just a local bubble or does it have a huge effect directly above? I assume that it does but is there a cut off point?

[picog]

Fair point, would you like me to split it into twenty year periods then?

My conclusion based on the available data over the fifty year intervals would be that the 2000-2049 period sees more 10C+ years than the fifty year period from 1950, and also that the number of 8.99C< years will also be less than the number of 10C+ years, a feat only achieved since 1700 by the 1950-1999 period.

As for global temperatures, 2011 is likely to be cooler than 2010, but 2013 will be warmer than 2010, provided no El Nino.

Doesn't that argument only apply to the paltry amount of time that we have relatively accurate temperature records for the earth?

[Thundery wintry showers]

It's a long enough period of time to show that global temperatures, and temperatures in the CET zone, are currently rising.

[Essan]

Doesn't that argument only apply to the paltry amount of time that we have relatively accurate temperature records for the earth?

Well obviously! What's your point? The CET was much, much, much, much lower for most of the past 3,000,000 years .....

[Gray-Wolf]

I have to re-stress that the UHI effect is taken into account when temps are taken (Mr schneiders explaination here http://news.sbs.com....302#watchonline) but must also emphasise that this is indeed another facet of mans impact on the climate of the planet. We even see an increase in storms/lightening strikes from the major cities in 'thunderstorm zones' (Florida/Texas in the U.S.).

So much for that 'butterflies wing beat' eh?

Edited September 29, 2010 by Gray-Wolf

[Iceberg]

UAH (satelite so whole earths surface is measured, does not include any surface sites) Average least 12 month +.50C

GIS (temperatures taken from surface sites for land and SST satelite for sea) Average least 12 month .53C

RSS (satelite so whole earths surface is measured, does not include any surface sites) Average least 12 month +.51C

HADCRU (temperatures taken from surface sites for land and SST satelite for sea) Average least 12 month 0.50C

NCDC (temperatures taken from surface sites for land and SST satelite for sea) Average least 12 month 0.63C

HADCRU atmospheric drops +.50C

I really think people need to wake up and smell the coffee, if anybody can look at this and say that UHI has any unaltered for effect, I'll eat my hat. !

What it does show is very good consistence between skeptic/AGW bodies, Sat or ground measurements for global temps.(and they all have 2010 as being one of the top 2 years in their respective histories.)

[Devonian]

UAH (satelite so whole earths surface is measured, does not include any surface sites) Average least 12 month +.50C

GIS (temperatures taken from surface sites for land and SST satelite for sea) Average least 12 month .53C

RSS (satelite so whole earths surface is measured, does not include any surface sites) Average least 12 month +.51C

HADCRU (temperatures taken from surface sites for land and SST satelite for sea) Average least 12 month 0.50C

NCDC (temperatures taken from surface sites for land and SST satelite for sea) Average least 12 month 0.63C

HADCRU atmospheric drops +.50C

I really think people need to wake up and smell the coffee, if anybody can look at this and say that UHI has any unaltered for effect, I'll eat my hat. !

What it does show is very good consistence between skeptic/AGW bodies, Sat or ground measurements for global temps.(and they all have 2010 as being one of the top 2 years in their respective histories.)

Thanks for the figures Ice. I must say I can't see how the UHI argument works given the satellites are in such close agreement with the surface record.

It's also interesting to be looking at such data again. It really speaks for itself.

[Gray-Wolf]

Thanks for the figures Ice. I must say I can't see how the UHI argument works

It only works if you stop at your 'o' level geography understanding of the phenomena and do not credit anyone with intelligence beyond this. As the 'debate' with the late Mr Schneider highlights well some folk will stop where they are happy and refuse to move forward if the greater understanding challenges their personal stance?

[Timini Cricket]

Thanks for the figures Ice. I must say I can't see how the UHI argument works given the satellites are in such close agreement with the surface record.

It's also interesting to be looking at such data again. It really speaks for itself.

No-one doubts the UHI phenomenon is real and measurable. If the satellites record the whole land surface temperatures, they presumably record the UHI increased temperatures too (how could they exclude them?). If in agreement with surface measurements, those surface data must, by inference, be UHI contaminated too, despite the homogenisation etc.

Edited September 29, 2010 by Timini Cricket

[Iceberg]

No-one doubts the UHI phenomenon is real and measurable. If the satellites record the whole land surface temperatures, they presumably record the UHI increased temperatures too (how could they exclude them?). If in agreement with surface measurements, those data must, by inference, be UHI contaminated too, despite the homogenisation etc.

Yes but the amount of the earths surface which is urbanised is considerably less than 1% something like 0.01% if memory serves, so the contamination of sat data might be 0.005C at the absolute most. i.e meaningless.

[Pennine Ten Foot Drifts]

UAH (satelite so whole earths surface is measured, does not include any surface sites) Average least 12 month +.50C

GIS (temperatures taken from surface sites for land and SST satelite for sea) Average least 12 month .53C

RSS (satelite so whole earths surface is measured, does not include any surface sites) Average least 12 month +.51C

HADCRU (temperatures taken from surface sites for land and SST satelite for sea) Average least 12 month 0.50C

NCDC (temperatures taken from surface sites for land and SST satelite for sea) Average least 12 month 0.63C

HADCRU atmospheric drops +.50C

I really think people need to wake up and smell the coffee, if anybody can look at this and say that UHI has any unaltered for effect, I'll eat my hat. !

What it does show is very good consistence between skeptic/AGW bodies, Sat or ground measurements for global temps.(and they all have 2010 as being one of the top 2 years in their respective histories.)

But despite these figures, 31% of respondents on here (where you'd assume personal interest has led to more research and a better informed opinion) believe that the world's surface temperature 'seems to be decreasing' ??? In view of that I would suggest debate is pretty much futile/pointless since black is clearly now white, and 1+1 does in fact equal 3......................

[The Future]

But despite these figures, 31% of respondents on here (where you'd assume personal interest has led to more research and a better informed opinion) believe that the world's surface temperature 'seems to be decreasing' ??? In view of that I would suggest debate is pretty much futile/pointless since black is clearly now white, and 1+1 does in fact equal 3......................

I'm one of the 31%ers. Yes, temperatures have been increasing but I do not think they are right now, I think they will decrease next year and maybe deccrease a little further for another 10 years or so. Debate is not futile, I seek the truth not a desired outcome. The only thing that might be futile is this poll because there are no timescales in the question.

[Guest mycroft]

UAH (satelite so whole earths surface is measured, does not include any surface sites) Average least 12 month +.50C

GIS (temperatures taken from surface sites for land and SST satelite for sea) Average least 12 month .53C

RSS (satelite so whole earths surface is measured, does not include any surface sites) Average least 12 month +.51C

HADCRU (temperatures taken from surface sites for land and SST satelite for sea) Average least 12 month 0.50C

NCDC (temperatures taken from surface sites for land and SST satelite for sea) Average least 12 month 0.63C

HADCRU atmospheric drops +.50C

I really think people need to wake up and smell the coffee, if anybody can look at this and say that UHI has any unaltered for effect, I'll eat my hat. !

What it does show is very good consistence between skeptic/AGW bodies, Sat or ground measurements for global temps.(and they all have 2010 as being one of the top 2 years in their respective histories.)

I think some one has finaly woke and smelt the cofee!!and this time its not coming from sceptics

A few extracts from the meeting at Exeter on the GHCN and USHCN etc

"Undocumented changes [in the USHCN] can be as prevalent as documented changes even when extensive (digitized) metadata are availableâ€

“Collectively station changes [in the USHCN] often have nearly random impacts, but even slight deviations from random matter greatlyâ€

"Outside of the USA ~60% of the GHCN Version 3 average temperature trends are larger following homogenizationâ€

“There is a need to identify gradual as well as abrupt changes in bias (but it is may (sic) be problematic to adjust for abrupt changes only)â€

"More work is required to assess and quantify uncertainties in bias adjustmentsâ€

“Critiques of surface temperature data and processing methods are increasingly coming from non traditional scientific sources (non peer reviewed) and the issue raised may be too numerous and too frequent for a small group of traditional scientists to addressâ€

“There is a growing interest in the nature of surface temperature data (reaching up to the highest levels of government)â€

Usage restrictions

Realistically we are not suddenly going to have open unrestricted access to all withheld data. In some areas this is the majority of the data.â€

I find this quite telling! why with hold data....again, everyone still sure that global temps can be taken as gospel when even the people entrusted to so are raising statements like the above

Edited September 29, 2010 by mycroft

[Thundery wintry showers]

I'm one of the 31%ers. Yes, temperatures have been increasing but I do not think they are right now, I think they will decrease next year and maybe deccrease a little further for another 10 years or so. Debate is not futile, I seek the truth not a desired outcome. The only thing that might be futile is this poll because there are no timescales in the question.

Actually you raise a very good point there. Do we mean global temperatures right now, rather than what the long-term trend is? If so, there would be a case for "seems to be decreasing" in view of the demise of the El Nino.

If the question had been "what is the long-term trend in global temperature?" then would we have seen a significantly different set of results? Personally I doubt it, but it is a possibility.

[stewfox]

“Critiques of surface temperature data and processing methods are increasingly coming from non traditional scientific sources (non peer reviewed) and the issue raised may be too numerous and too frequent for a small group of traditional scientists to addressâ€

Unfortunately they will just have to remain open to wider audience, we all live on the same planet.

[Guest mycroft]

Unfortunately they will just have to remain open to wider audience, we all live on the same planet.

Very true.But the example above sounds like excuse for doing nothing,as it sound as if its expected that the small group of traditional scientists are expected to visit every site and collect the historical data when every one knows that each site has an observer who could just email through that data as they do with the observations everyday :lol:

[Northernlights]

I'm one of the 31%ers. Yes, temperatures have been increasing but I do not think they are right now, I think they will decrease next year and maybe deccrease a little further for another 10 years or so. Debate is not futile, I seek the truth not a desired outcome. The only thing that might be futile is this poll because there are no timescales in the question.

On a very micro climate scale on this tiny part of the planet I know it has been cooler on the farm for the past 4 years with reduced winter growth of grass and a return to feeding the sheep from late January onwards till April and in the case of last year from late December till the April. It has also been a much shorter growing season this year than last with a late frost and snow on the 12th of May which damaged the plum blossom in the garden and I think also reduced the barley crop(both straw and grain) although the drought in June did not help.

Also within the last month there have been 3 occasions when snow has fallen and lain all day above 3000 feet on the surrounding mountains and only last Monday we had an air frost of -1c something I have looked for in past farm diaries in Septembers going back to the sixties and can only find on odd occasions It is definitely cooler here for whatever reason and as I passed the snow poles tonight that were installed on the A96 at sea level around about 8 years ago during the time of BBCc Snowwatch and which I commented on at the time I think how useful they were last winter and perhaps someone in the roads department thought we were heading for cooler winters then. The Cairngorm ski road last Februaryand snowfall on the 12th of May 2010

[Essan]

Well clearly global cooling is happening because it's colder in my back garden now than at bny time in the past 48 hours! :lol:

btw it intrigues me that proponents of AGW dismiss UHI whilst those who refute AGW raise the issue - when in my mind UHI is the clearest, most obvious, example of AGW. Oh well, as I said earlier, I'm a lone (or, I see, not entirely a lone) voice on this issue.

But if you have a massive aircraft hanger, and light a dozen candles on the floor, are are telling me that this does not raise the temperature of the hanger, by however small an amount, irrespective of whether anything else also raises (or cools) the temp? And looking at a night-time sat image of the Earth, I would say urbanisation affects rather more of the planet that people appreciate. And it adds several degrees warming to those parts affected. The net result, IMO, is that regardless of anything else, human activity raises the surface temp. And when we take into account other land use changes ......

If the question had been "what is the long-term trend in global temperature?" then would we have seen a significantly different set of results? Personally I doubt it, but it is a possibility.

That depends on the timescale. But on any timescale less than thousands of years it is downward. And even over the past 5,000 years the trend has been downward - which is what makes current warming so strange. It seems to buck the trend. Unless it's a brief blip and the next LIA will be colder yet .....

Although at some point in the next few thousand years the trend should temporarily reverse back upwards - before the next downward spiral into the next full glacial.

Edited September 29, 2010 by Essan

[cheeky_monkey]

And looking at a night-time sat image of the Earth, I would say urbanisation affects rather more of the planet that people appreciate. And it adds several degrees warming to those parts affected. The net result, IMO, is that regardless of anything else, human activity raises the surface temp. And when we take into account other land use changes ......

I think this is a fair point that probably not many people have considered (i know i havnt)..increasing globalisation and urbanisation would cause a global urban heat island of some sorts that simply would not have existed 50-100 yrs ago to the extent it does today.

[weather eater]

Interesting discussion in regards the Roman warm period and the medieval warm period. The first thing to say is that I don’t doubt that temperatures in those periods may have been as High as today’s. In terms of the medieval warm period it was not a period of continual warmth, it did have cooler interludes I suspect the Roman period was the same.

One of the problems in getting to grip with both of these periods, as well as the little ice age, is ascertaining start and end points, it can all rather depend on what and who you read. Mycroft used some dates in his post on the polar ice thread.

Roman warm period AD 1 - AD 300, some sources put this at 250 BC - AD 400, that’s a range somewhere between 300 and 650 years.

Medieval warm period AD 800 to 1300, yet again this is another difficult one to pin down, however I feel Mycroft’s AD 800-1300 is not far of the mark, that’s a 500 year warm period.

The same applies to the little ice age, Mycroft has it at AD 1300 - AD 1900, personally I’m not so sure about that I would call it at nearer AD 1550 - the early 1800s.

The first thing to note is that these natural climate changes last for hundreds of years. The second thing to note is the lengthy gaps of more regular conditions.

RWP AD 1 to AD 300 or 250BC to AD 400

Then a gap AD 300/400 - AD 800, cooler but not akin to the little ice age.

MWP AD 800 - AD 1300

Then another gap, depending on who you believe, certainly there was a change to cooler conditions after AD 1300, cold winters became more of a fixture, but not into the full blown LIA, if we take the AD 1550 figure that’s a 250 year gap, between the MWP and the LIA.

LIA 1300? Or 1550 to early 1800s

A gap possibly from the early 1800s - the 1970s, yet again difficult to call maybe 1975/76

The third thing of note is the length of those warm periods

RWP - somewhere between 300 and 650 years

MWP - 500 years.

LIA - between 250 years and 500 years

If the length of these periods is indicative of the length of natural warm and cold cycles. and if, as some would have it, and that the warmth we are now seeing is part of a similar natural cycle, then we are only at the start of, or at best only half way in to, a lengthy warm spell.

Lets say we count the start of this warm spell as 1970 that then would mean that it will last another 300 - 500 years. Even if we were to set the start date at the end of the LIA then that would still suggest we have between 100 and 300 years left to go, before we enter a cooler phase.

Of course as I said at the start of the post the MWP was not a continual spell of warmer temperatures, it did contain colder periods. If we are going to use the MWP as a yard stick for the current warming then that suggests that even if we enter a cooler phase over the next few years, the warming will resume.

[jethro]

Here's quite a good site for info on historical weather in the British Isles:

http://www.booty.org.uk/booty.weather/climate/histclimat.htm

[summer blizzard]

On a side not to the main disscusion, and not taking into the account of localised cooling events like the NAD, it should be noted that due to the axial tilt of the Earth, global warming aside we will enter the next major glacial period in 7000-8000 years, with the peak in around 50000 years, it would be interesting to the see the effect of man made warming on this. As such, we should in theory of seen out thermal peak around the Roman warm period.

Edited September 29, 2010 by summer blizzard

[weather eater]

Here's quite a good site for info on historical weather in the British Isles:

http://www.booty.org.uk/booty.weather/climate/histclimat.htm

Hi Jethro, I do have lots of books on the subject plus of course there is the myriad of websites. The problem is none of them seem to agree on exact dates, plus of course the truth is that the climate has not jumped from one state to another so much as eased. For instance Brian Fagan in his book the little ice age puts the change from the MWP to the LIA at 1310 however he also notes that the first really harsh winter did no occur until 1559, nearly 250 years latter.

[Methuselah]

“Critiques of surface temperature data and processing methods are increasingly coming from non traditional scientific sources (non peer reviewed) and the issue raised may be too numerous and too frequent for a small group of traditional scientists to addressâ€

IMO Mycroft, what you say there highlights the problem: when mainstream academically-tested science fails to come up with the desired result, people will clutch the first straw that comes along...Witness the current explosion of completely untested (and, arguably, useless) 'alternative' health products??

[Guest mycroft]

IMO Mycroft, what you say there highlights the problem: when mainstream academically-tested science fails to come up with the desired result, people will clutch the first straw that comes along...Witness the current explosion of completely untested (and, arguably, useless) 'alternative' health products??

Could be?but the fact that the meeting took place means that those in charge of the data sets also have doubts.Anthony Watts surface project has raised the doubts,and downright absurd situation of some sites,and something is seriously wrong when in an age of supposed change of climate in the last 20 odd years that we have gone from (i think) many thousands of sites to around 1,900 globaly and very little coverage in the Artic to the point that data has been extrapolated to cover large areas with no sites.And its called robust science

methodology!!!!!