UHI, this is London

Since BEST claims they will work to take UHI into consideration, it seems worthwhile to highlight this new paper. Guess who’s a co-author? Phil Jones of UEA’s CRU.

Urban heat island (surface temperature) map of London, UK, September 16, 2003 Image from Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) click to enlarge
Image above from Arizona State, Center for Environmental Science Applications (CESA).

From Dr. Roger Pielke Sr.:

New Paper “Decadal Variations In The Nocturnal Heat Island Of London” By Wilby Et Al 2011

Weather

There is a new paper that adds significantly to our understanding of the urban heat island, and thus its role on long-term surface temperature records. The new paper is

Robert L. Wilby,Philip D. Jones  and David H. Lister: Decadal Variations In The Nocturnal Heat Island Of London. Weather March 2011. DOI: 10.1002/wea.679

The abstract reads

“Our review of the long-term behaviour of London’s UHI provides a salutary reminder that the appearance and disappearance of trends in environmental data can depend very much on the segment of data analysed. Nonetheless, we can confirm – using both daily and monthly temperature records – that the summer nUHI did intensify between the late 1950s/early 1960s and the 1980s. This period coincided with an abrupt increase in the frequency of summer anticyclonic weather. There is also evidence of a slight rise in the annual number of intense heat-island events that can be linked to more persistent anticylonic weather systems at that time. A weak decline in summer nUHI since the 1980s coincides with a rise in the frequency of cyclonic weather. Since 1931, the summer nUHI has risen slightly, but not significantly. The overall annual mean nUHI does, however, show a weak but significant (p<0.05) rise when the monthly SJP record is compared to that of WIS.”

Their concluding remarks read

Our review of the long-term behaviour of London’s UHI provides a salutary reminder that the appearance and disappearance of trends in environmental data can depend very much on the segment of data analysed.

Nonetheless, we can confirm – using both daily and monthly temperature records – that the summer nUHI did intensify between the late 1950s/early 1960s and the 1980s. This period coincided with an abrupt increase in the frequency of summer anticyclonic weather. There is also evidence of a slight rise in the annual number of intense heat-island events that can be linked to more persistent anticylonic weather systems at that time. A weak decline in summer nUHI since the 1980s coincides with a rise in the frequency of cyclonic weather. Since 1931, the summer nUHI has risen slightly, but not significantly. The overall annual mean nUHI does, however, show a weak but significant (p<0.05) rise when the monthly SJP record is compared to that of WIS.

Over the 50-year daily record, less than half of the variance in the summer-mean nUHI signal is explained by synoptic weather patterns. This could be due to a number of factors. The weather types describe conditions across the British Isles generally, rather than for southeast England specifically. The conditions experienced within a given weather class are known to vary from day to day. There have also been marked changes in regional air quality in the wake of the notorious winter ‘smogs’ of the 1950s and the summer stubble burning

of the 1970s and 1980s. Other time-dependent factors (such as artificial heat sources, building albedo, thermal mass, sky-view factors, surface roughness, and vegetated area) may be locally important (McGregor et al., 2006). Furthermore, censuses show that the population of Greater London peaked in 1939 then fell until 1991 and has since risen again.”

This paper is an important new addition to the literature on multi-decadal surface temperature trends.

==============================================================

Here’s the first page of the article from Wiley publishing:

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pat
April 2, 2011 10:06 am

Hmmmm

James ibbotson
April 2, 2011 10:18 am

I’m thinking the entire so called 20th century slight warming is primarily due to UHI.
That’s a start on a running retreat IMHO,

Jit
April 2, 2011 10:30 am

According to the website linked below, Wisley has the highest july temp for the UK (2006). If you really wanted an urban station in London, you’d pick Camden Square, which holds a number of record highs including for April and May.
http://www.torro.org.uk/site/maxtemps.php
The suitability of Wisley as a “rural” station could be debated. You can find its location on Google earth (search wisley, surrey; station is south east of the weird swirly garden).

Al Gore's Holy Hologram
April 2, 2011 10:49 am

London’s population is still 500,000 less than 1938 despite taking up three times more space and having the second largest influx of immigrants in the world, first being the US.

Rob Dawg
April 2, 2011 10:54 am

He came close but Jones just couldn’t bring himself to say that overnight minimum temperatures are not a good metric for identifying global warming trends.

golf charley
April 2, 2011 11:01 am

Is Jones going to lose the data for this one like he did for his 1990 Nature report on UHI?
Mike’s Nature Trick “Hide the Decline”
Phil’s Nature Trick “Lose the Data”

R. Gates
April 2, 2011 11:14 am

James ibbotson says:
April 2, 2011 at 10:18 am
I’m thinking the entire so called 20th century slight warming is primarily due to UHI.
That’s a start on a running retreat IMHO…
___
Not likely.

Editor
April 2, 2011 11:14 am

I wonder what the satellite map would have looked like in the 1930’s.
Another factor often overlooked is the effect of smog. (My mum told me I nearly died in the Great London Smog of 1952 when I was a baby). Daytime temperatures would have been lower when smog was around although I am not sure what the effect would have been at night.

steveta_uk
April 2, 2011 11:14 am

I wondered what Dave Lister had been doing since Red Dwarf.

Lady Life Grows
April 2, 2011 11:22 am

This is a good one, I hope, and a genuine contribution to actual climate SCIENCE. Ironically, Phil Jones had made his original repution on UHI. He has now an opportunity to repolish his image and that of his university, by dropping all mouthing of globull warming and increasing our understanding of UHI, a real (and often beneficial) phenomenon.
It is a lot of fun to sneer at idiots and you wonderkinder here do a magnificent job of it and I laugh my head off at your comments. But human progress is not really made by slamming people. This Phil Jones has been bruised (his fault, but we all screw up). He needs encouragement and this is just the thing to congratulate him on.
Thank you, Anthony. and Dr. Pielke.

netdr2
April 2, 2011 11:44 am

There is a 7 ° F difference between downtown Dallas and the surrounding countryside at about sundown on a clear summer day. I have measured it myself. I have a temperature recording thermometer [bought from this site] and started in downtown Dallas and drove the speed limit out to the country 35 miles away.
The “correction” applied to the closest site of record [DFW airport] has been about + .5 ° C which is the wrong direction ! It makes the temperature is Dallas even warmer.
I don’t know why the raw numbers are too low because the buildings runways and a small city which has sprung up around there since 1977 have to have raised temperatures due to UHI !

DirkH
April 2, 2011 11:47 am

“Since 1931, the summer nUHI has risen slightly, but not significantly. The overall annual mean nUHI does, however, show a weak but significant (p<0.05) rise when the monthly SJP record is compared to that of WIS."
They acknowledge the principal existence of UHI but say it doesn't contribute much; so, "here, that's handled, now stop bothering us with UHI". Nice try.
But we know that GISS exploits UHI in a very clever way.
http://www.warwickhughes.com/blog/?p=753

Roger Edmunds
April 2, 2011 12:05 pm

The thing I find interesting is from the thermal image that has been placed at the head of this piece. If that is a representative photograph then St James’s Park is at least 4 degrees cooler than the bulk of London. This would indicate that this is not a good site to demonstrate UHI in the city. I understand the need for long series of data but I would have thought there must be other, if shorter, series that would be more appropriate.
Does anyone know the precise location of the monitoring station?

Gary Pearse
April 2, 2011 12:36 pm

“Our review of the long-term behaviour of London’s UHI provides a salutary reminder that the appearance and disappearance of trends in environmental data can depend very much on the segment of data analysed.”
Phil is undergoing a slow rebirth. This reminder that cherry picking start dates for your trends can give you whatever you want. Phil had a career near-death experience over the past year and a half since climategate but seems to be recovering. I had to grudgingly admire his statement back then that there had been no statistically significant warming since 1995 and I believe we can look forward to more science-based work from him.
This is a lot different than the dogged persistence with attempts to salvage some semblence of the hockey stick and the woeful tree ring circus by the bunch that prefer to remain under seige. Probably Pachari is secretly shoveling the snow off the Himalayas, too. Schneider and Ehrlich – former new-ice-age fanatics morphed into CAGW zealots in a few years. Meanwhile CAGW has diminished to AGW, then to climate change, to climate disruption and what? Climate ripples as cooling continues sealevel begins to peak.

eadler
April 2, 2011 12:46 pm

London is an old well established city. Reading the screen shot of the 1st page of the paper, one of the things the author’s point out, is that the temperature increase, since 1907, has been the same for the rural and urban stations that were studied.
I don’t believe that Jones ever denied the reality of the UHI. What he and the other scientists studying the global temperature record try to do is eliminate any bias from the UHI from the temperature record.

SayNoToFearmongers
April 2, 2011 12:47 pm

Jit,
Fair comment about the Wisley met station being not exactly rural – those structures 20m away are large polytunnels, covering several hundred square metres. On hot days these will be ventilated by opening the ends (and possibly sides) to dissipate the awesome 50 deg. C+ that they’d otherwise contain. I’d suspect that this huge heat source is within a range that might impact on those thermometers.

David Y
April 2, 2011 12:52 pm

Hello R. Gates,
I realize you often find yourself in a bit of contention with the other locals here. Kudos to you for taking the time to voice your views and taking (perhaps welcoming!) the criticisms in this arena.
In a recent exchange, you mentioned some issues relating to the onset and progression of ice ages. I find this area particularly interesting. I am not a formally trained meteorologist or climatologist, but just someone who is fascinated by all this ‘stuff’–perhaps the more so because I grew up in southeastern Wisconsin, an area heavily influenced by the last ice age.
I’m skeptical of the accuracy/validity of the current scientific establishment’s explanations of the onset of ice ages. This doesn’t mean I don’t think they may be correct–rather, no scientific argument has been put forth (that I’ve seen) that fully explains it. So I’m asking you (since others here have not offered any assistance in this matter–though I would fully welcome input from this group) for your suggestions on what the most complete, compelling and defensible arguments (ideally including the math behind them!!!) are for the current prevailing theory(ies) on the onset of continental glaciation/ice ages. I believe arguments put forth thus far are too simplistic.
And while I may disagree with a fair portion of your views expressed here, at the end of the day we all benefit by ever more rigorous examination of our views and from being willing to listen to others. (True listening is the willingness to be altered by what you hear, after all.)
Thank you & have a good weekend,
DY

wayne
April 2, 2011 12:59 pm

They had better remove the UHI factor from present day temperatures, keeping that upward UHI factor series separate, so you can apply it or not, or this BEST is just more junk science, simply trash.

old44
April 2, 2011 1:02 pm

Lady Life Grows says: April 2, 2011 at 11:22 am
Lady Life, there is a world of difference between screwing up and consciously setting out to deceive people.

BillyBob
April 2, 2011 1:07 pm

Heathrow weather station has bright sunshine hours up over 220 hours per year. I suspect thats because of the cleaning up of the air.
Decade Sunshine Hours Total
1960s – 14555.7
1970s – 15118.6
1980s – 15264.4
1990s – 16801.9
2000s – 16776.8
http://www.metoffice.gov.uk/climate/uk/stationdata/heathrowdata.txt
2300 extra hours of sunshine from the 1960s to the 1990s/2000s.
That is a huge jump in energy from the sun.
Jones may be measuring the wrong thing again …

wayne
April 2, 2011 1:30 pm

This really ticks me!!
Daytime summer temperatures are minimally affected by UHI, it is the winter nighttime temperatures where urban heat manifests itself the greatest. There is too much energy from the sun present on hot summer days. But in cold winter days and nights that urban heating really takes it toll on the anomalies.
Every rural station here in Oklahoma shows that same pattern. It makes it look like the Earth is warmer but it is mainly that we have warmer winter nights due to towns and cities. If you were to say that it doesn’t matter that January nights were 2 degrees warmer more recently then Oklahoma as a whole would show very little to no change since 1880 at all. Go pull up you nearby rural stations showing minimum and maximum plots seperately and you should see this, I think it is found at NCDC though I thought it had five letters.
We’ve been through all of this before.
What do we have, another sham going? Another brainless exercise in the misnomer called “CLIMATE SCIENCE”. Now it’s called the “BEST”. Do these people called “climatologists” not have brains?

wayne
April 2, 2011 1:59 pm

The bottom line is this, until they seperate the seasons, the mid-spring to mid-fall and the mid-fall to mid-spring, and, keep seperate the maximum daytime records from the minimum nightime records, there is simply no hope on really seeing what the climate is doing. At least that is what the last sixteen months of digging deep into climate science has taught me.
Maybe they just need a very good scientific programmer? Maybe they just don’t know how to program that. Huh? There are still some around.

Doug S
April 2, 2011 2:05 pm

David Y says:
April 2, 2011 at 12:52 pm
….
I’m skeptical of the accuracy/validity of the current scientific establishment’s explanations of the onset of ice ages. This doesn’t mean I don’t think they may be correct–rather, no scientific argument has been put forth (that I’ve seen) that fully explains it.
….

I’m not a trained scientist David but I find Dr. Svensmark’s hypothesis for Gamma ray cloud seeding to be particularly interesting. I think the long period between ice ages can be simply explained by our solor system orbiting with the galaxy. As we pass through bands of high Gamma ray flux the cloud cover increases and cooling dominates. Moving out of the Gamma ray flux allows warming to occur. It’s simple explanation, I like it.

April 2, 2011 2:20 pm

DirkH,
Thank you for posting that excellent graphic showing how GISS massages the past temperature record.

jaymam
April 2, 2011 2:39 pm

A similar urban heat island map of an entire country, e.g. the UK or US, with the positions of all weather stations marked on it, would be excellent publicity for the skeptic point of view.

Braddles
April 2, 2011 2:45 pm

Sorry, I skimmed this one. There are some scientists who do not deserve to be read, regardless of which side of the debate a particular paper may appear to support. Jones is by now such a completely political operator that nothing he writes could be taken at face value.

Stephen Brown
April 2, 2011 2:48 pm

I live on the south coast of England and I’m an avid gardener, I like to grow food for my family. Our climate is generally quite benign but, on cool evenings, I look around and wish that I could capture all of the waste heat I see (via the condensation) being vented from every house in my immediate vicinity.
People here use their gas boilers to heat water for domestic use, the same boiler also does double duty in heating the house. I don’t know how much of the heat generated by the gas flames is transferred to the house or hot water system, but I do know that an awful lot is simply vented to the atmosphere.
If I could harness that waste heat I’d be able to start seeds germinating in my poly-tunnel and greenhouse in January!
Most houses in England are now heated by gas; how much cognisance has been taken of this fact when considering how much heat is pumped into the atmosphere above a densely populated city?
Very little, I suspect.
Oh, and all of that gas which is burned is CO2-intensive!

Theo Goodwin
April 2, 2011 2:51 pm

wayne says:
April 2, 2011 at 1:59 pm
“The bottom line is this, until they seperate the seasons, the mid-spring to mid-fall and the mid-fall to mid-spring, and, keep seperate the maximum daytime records from the minimum nightime records, there is simply no hope on really seeing what the climate is doing. At least that is what the last sixteen months of digging deep into climate science has taught me. Maybe they just need a very good scientific programmer? Maybe they just don’t know how to program that. Huh? There are still some around.”
Amen, Brother, Amen! Yeah, you would think Climate Science cannot afford computers for data. Billions for supercomputers for simulations but pennies for data recording. I think it is still standard practice to record a daily temperature as an average of a daytime and a nighttime temperature. DUH!
We need a record of daily highs, a record of daily lows, a record of nightly lows, a record of nightly minimums, and several more things. But these records cannot be extracted from anyone’s temperature records because they did not keep them.
The entire enterprise known as Climate Science is erected on a foundation of temperature measurements that are worthless. It is time to start over. Climate scientists and sceptics should work together to create a new temperature measurement regime that both can approve. Then maybe in fifty years we will have a climate science that is worth its name.

Theo Goodwin
April 2, 2011 3:02 pm

Lady Life Grows says:
April 2, 2011 at 11:22 am
“It is a lot of fun to sneer at idiots and you wonderkinder here do a magnificent job of it and I laugh my head off at your comments. But human progress is not really made by slamming people.”
What an interesting choice of words. I have not slammed Jones. But I do want to see him and his little friends in the slammer. The scales of justice do not automatically reposition. Someone has to pay.

kbray in California
April 2, 2011 3:31 pm

If warmists soon can have their way
A new future will be here to stay
No cars, no trains, no aeroplanes
They really have bollsh!t for brains…

Noblesse Oblige
April 2, 2011 3:47 pm

Does anyone know who (D or R) invited Muller, in preference to a number of others with long, broad experience on the data issues (e.g., Watts, DAleo, Pielke Sr., Klotzbach…)

Latitude
April 2, 2011 4:07 pm

Is this the same Phil Jones that lied before?…………….
Fool me once…………..

April 2, 2011 4:11 pm

Stephen Brown @ April 2, 2011 at 2:48 pm
The quantity of heat lost is a function of the efficiency of the boilers, which might be as low as 50% seasonally, or as high as 96%; and, of the size and structure of the house.
The exhaust can contain as much as 10-12% CO2, so both the heat and the CO2 could be useful in your poly-tunnel and greenhouse. However, that exhaust can also contain some CO (~50 ppm if combustion is proper and up to several hundred ppm if the combustion system is not adjusted properly). Many of the plants you might be raising would be highly sensitive to that CO, so extreme care would be required if the exhaust were introduced directly into the plant environment. Also, the condensed water from the exhaust is acidic, with a ph of ~4.

Jeff
April 2, 2011 4:21 pm

Lady Life …
we all screw up ??? really … have you ever purposely lied and hidden data on your job ? because everyone doesn’t lie and hide data on the job … Jones did not “screw up”, he lied and obstructed science and legal information requests …
funny thing about bashing … since when is describing a criminals behavior bashing ?

Sam Hall
April 2, 2011 4:22 pm

All this concern about a once or twice a day temperature reading. What is needed is a measure of the energy received over a day. One way, which isn’t great, but is far better than the current method, would be to measure the temperature every minute over a day. Then you integrate the area under the curve and you have a measurement that has some value.

April 2, 2011 4:29 pm

The thermal map is interesting in that I initially could not make sense of the heat distribution. Hyde Park, Regents Park and Blackheath show up as hotter than surrounding roads and buildings, while Richmond park has both hottest and coldest temps with a 14C difference between the top and bottom of the park.
On closer inspection these temperature extremes can be explained by the nature of these open spaces. The warmest parts are short grass and the coolest are either trees or water. it is possible to see the outline of the Serpantine and the woods next to it in Hyde Park. The dark areas in Richmond are trees. In addition other wooded areas are clearly defined, such as Dulwich Woods. Looking closer still the green just on the north side of Dulwich Woods is a golf course, with short grass, but it is not hot. However there is a hot spot just above the golf course which are cricket pitches. Looking at Google Earth you can see the that the golf course is watered more than the cricket pitches which will make it cooler.
What is also interesting is that short dry grass will have a higher albedo than trees or water and yet albedo appears to play no part in these temperature differences. Further more the darkest patches in this image are either water or trees.
What I don’t understand is the relatively cool colour of the City of London and the dark band at bottom right. This area is a west facing ridge made up of farm land and woods, and somewhere in the dark blue is the small town of Swanley.

April 2, 2011 4:32 pm

Sorry. correction to previous post.
“This area is a west facing ridge made up of farm land….”
Should be “This area is an East facing ridge…”

Theo Goodwin
April 2, 2011 4:39 pm

Sam Hall says:
April 2, 2011 at 4:22 pm
“All this concern about a once or twice a day temperature reading. What is needed is a measure of the energy received over a day. One way, which isn’t great, but is far better than the current method, would be to measure the temperature every minute over a day. Then you integrate the area under the curve and you have a measurement that has some value.”
Yes, we need really sophisticated measures, not just temperatures. But then there would be no question that there is no global warming, aside from UHI and such, and what would our little climate buddies do for grant money? They cannot do science. However, no one should ever forget that they totally botched the temperature record and continue do so.

LarryT
April 2, 2011 4:40 pm

My feeling is if a journal article is authored, co-authored by one of the team it really can not be accepted as legitimate until it has been throughly vetted by non-team members and maybe 3-5 years have passed without a refutation.

Theo Goodwin
April 2, 2011 4:56 pm

Stephen Skinner says:
April 2, 2011 at 4:29 pm
“The thermal map is interesting in that I initially could not make sense of the heat distribution. Hyde Park, Regents Park and Blackheath show up as hotter than surrounding roads and buildings, while Richmond park has both hottest and coldest temps with a 14C difference between the top and bottom of the park.”
Stephen, please, climate scientists can work with only one temperature at a time. No doubt they will average the temperatures you identify. /sarc off
Seriously, it is wonderful to hear from a man who loves reality. Your report makes it quite clear that Jones’ work could not do the area justice. This is true generally of temperature data produced by climate scientists. They must create ABSTRACTIONS at a huge distance from the reality before they can reach the desired results. Consequently, their temperature record is totally wimpy and inadequate to the task.
As regards UHI, would someone please go to St. Louis, MO, the old city not the newer suburbs, and do a UHI study there. A person who cannot feel the pain of the UHI during warm months and the comfort of UHI during the cold months is stone cold dead. We are talking in excess of ten degrees between the old city, to Skinker in the West, and the open areas, like Wild Horse Creek Road in West County.

mike g
April 2, 2011 5:00 pm

@netdr2
I have seen the temp go from 90 degrees at the eastern edge of the Dallas sprawl, 102 downtown, and back to 90 going out of the sprawl on the north side.

Sleepalot
April 2, 2011 5:03 pm

Following on from Mr Skinner’s observations, I
focused on the big hot-spot (top right) which
turns out to be green fields in the Little Heath area. I suspect the date (16 Sept)was chosen to minimise the appearance of UHI.

wayne
April 2, 2011 5:11 pm

@ Theo Goodwin
Seems you got my point. You must have a good logical mind to see that, and why.
Phil Jones is already totally misunderstanding UHI itself. It has two causes and two different effects and he can’t seem to see it, once again. I doubt if BEST will either. Of course, they probably never stop to think.

BillD
April 2, 2011 5:21 pm

The really big anomalies are in the arctic, as predicted by climate models. Is this due to UHI?

Sleepalot
April 2, 2011 5:25 pm

The two thermal images of England here:-
http://www.seedgen.com/thermallondon/space.htm
show that UHI is less apparent on warm days.

Olavi
April 2, 2011 5:41 pm

I wont trust any paper if there is name P. Jones, M. Mann or G. Smith if theyll get honest reputation back, they start cheating otherways. Bad science and now BOOM this is the truth. HAH

Latitude
April 2, 2011 6:00 pm

BillD says:
April 2, 2011 at 5:21 pm
The really big anomalies are in the arctic, as predicted by climate models. Is this due to UHI?
================================================
Bill, the climate computer games predicted both poles.

Scott
April 2, 2011 6:09 pm

BillD says:
April 2, 2011 at 5:21 pm

The really big anomalies are in the arctic, as predicted by climate models. Is this due to UHI?

How many temperature sensors are in true rural areas of the Arctic? They’re all near inhabited areas. If you measure the temperature 10 ft away from a campfire both before and after the fire is lit, do you expect to see a bigger change in temp when it starts at 35 C or at -35 C before the fire is started?
The point is, a running car/truck 10 ft away from a thermometer on a hot summer day has a much smaller impact than on a thermometer in a small town in far northern Canada in the middle of the winter.
-Scott

rbateman
April 2, 2011 6:20 pm

I am trying hard to figure out something of value to civilization to be had from these global climate studies.
The biggest problem they have is that their models cannot get a single seasons forecast right. There is little value there.
As for UHI affected urban centers vs rural, there is some merit in knowing how much temperatures will drop in the cities (in winter), when the greens who use the GCM output to justify outlawing all forms of heating achieve thier goals.
That difference between urban and rural winter temps is the amount of jeapordy the general population will be thrown in.

Mindbuilder
April 2, 2011 6:25 pm

THERE IS NO SIGNIFICANT URBAN HEAT ISLAND EFFECT ON TEMPERATURE TRENDS! EVEN ANTHONY WATTS APPEARS TO RELUCTANTLY ADMIT THIS. “…the mean temperature has no statistically significant trend difference that is dependent of siting quality…” – Anthony Watts – http://wattsupwiththat.com/2011/03/31/clarification-on-best-submitted-to-the-house/#more-36957
Anthony did find a significant trend in nighttime lows which have been getting warmer in cities, and in daytime highs, which amazingly seem to have been maintaining their cool better than the rural sites. Anthony’s study was for the US so the story might be different for other parts of the world, but it seems unlikely. It is also still possible that there has been some kind of trick pulled on the temperature record. But some say the satellites are consistent with the ground records and rule out any more than slight UHI effects on the trend. It’s important to realize that I’m not saying there is no UHI. I’m only saying there was just about as much UHI in cities of the past, and to the extent UHI has increased, it hasn’t increased enough to make much difference.

April 2, 2011 6:26 pm

Jones voted against UHI before he voted for it, before he voted against it, before he voted for it …

Keith Minto
April 2, 2011 6:30 pm

I think that the real aim of this paper (yes, it is political) is to discredit UHI as a consistent, measurable effect. The paper mentions variable wind speed and direction, anti-cyclonic weather patterns (high cells, sinking air and generally clear weather). I have even seen articles that link UHI to the ‘weekend effect’ when cities cool as the inhabitants leave on the weekend.
The next step would be to establish the trend as the best guide for warming.
As for measuring temperature, looking at the problems with max/min and time of reading, my suggestion is to to select max only and pick the sun’s zenith as the reading time in each location. I know that temps rise after this, but mins and late afternoon readings will have thermal earth heat bank signals that muddy the measurement.
The sun’s zenith is a fair standard that can be applied world wide, certainly is simpler than now.

April 2, 2011 7:30 pm

The continent with a large land area, a long and good temperature record with both Tmax and Tmin, a large number of truly rural sites, the majority of the population in a few large cities, good census records, good weather records in general – is Australia.
Just about every objection to methodology I have read in the analysis of other authors can be overcome by a close study of Australia. It is in progress. It will be less prone to assumptions that any I have read. Do not lose faith that a definitive answer is possible.
Places like the surroundings of London, or certain sites in China, will not show much UHI because it had already neared a plateau before the analysis was done. Australia has many, many places where breezes blowing from one population center to another will be untainted.

dp
April 2, 2011 7:31 pm

According to Muller’s video, if Jones is one of the Team he won’t bother reading any longer. Guess that’s a wasted paper (or a hollow threat on Muller’s part). But then we know now he is not seeking the Nobel prize for transparency and honesty in science.

LazyTeenager
April 2, 2011 7:58 pm

netdr2 says:
April 2, 2011 at 11:44 am
There is a 7 ° F difference between downtown Dallas and the surrounding countryside at about sundown on a clear summer day. I have measured it myself. I have a temperature recording thermometer [bought from this site] and started in downtown Dallas and drove the speed limit out to the country 35 miles away.
————
And you did this in a car that had been standing in the sun all day AND at the time of day when the temperature is falling fast.
I am the only person who sees something wrong with this?

Dickens Goes Metro
April 2, 2011 7:59 pm

Hide the incline (UHI)?

AusieDan
April 2, 2011 8:20 pm

I agree with several people who have noted that in order to understand UHI and temperature trends, it is necessary to seperate out maximum from minimum and to examine trends seperately, month by month.
In doing so, I was able to identify the onset of UHI in the temperature record at Observatory Hill, in the heart of Sydney, Australia.
I was also able to connect this onset of UHI with a historic change in the built environment immediately adjacent to the Stsphenson screen and also the impact of the changing prevailing winds on the rate of UHI increase that occur in different seasons of the year.
UHI at Observatory Hill has a trend change impact on measured temperature which steadily increases each year in a linear fashion, most in winter and least in summer, which is also consistent with other comments to this post.

eadler
April 2, 2011 8:23 pm

Doug S says:
April 2, 2011 at 2:05 pm
David Y says:
April 2, 2011 at 12:52 pm
….
“I’m skeptical of the accuracy/validity of the current scientific establishment’s explanations of the onset of ice ages. This doesn’t mean I don’t think they may be correct–rather, no scientific argument has been put forth (that I’ve seen) that fully explains it.
….

I’m not a trained scientist David but I find Dr. Svensmark’s hypothesis for Gamma ray cloud seeding to be particularly interesting. I think the long period between ice ages can be simply explained by our solor system orbiting with the galaxy. As we pass through bands of high Gamma ray flux the cloud cover increases and cooling dominates. Moving out of the Gamma ray flux allows warming to occur. It’s simple explanation, I like it.
You guys are not looking very hard.
Here is a description of what triggers the glacial cycles, the Milankovitch cycles which affect the earth’s orbit and axial tilt:
http://www.homepage.montana.edu/~geol445/hyperglac/time1/milankov.htm
Here is a description of the data, and a historical account of the Milankovitch theory of glaciation which shows how the theory was developed and confirmed during the 1960’s and 1970’s.
http://earthguide.ucsd.edu/virtualmuseum/climatechange2/03_1.shtml

Theo Goodwin
April 2, 2011 8:41 pm

wayne says:
April 2, 2011 at 5:11 pm
“@ Theo Goodwin
Seems you got my point. You must have a good logical mind to see that, and why.
Phil Jones is already totally misunderstanding UHI itself. It has two causes and two different effects and he can’t seem to see it, once again. I doubt if BEST will either. Of course, they probably never stop to think.”
Thank you. I really cannot understand why Phil Jones is taken seriously in any way whatsoever. He is no scientist. He does not have the instincts of a scientist.
With your description of the area that Jones studied, we should be off on another lark as we were with extinct sloths and such. I guess people just cannot get their minds around UHI. Maybe most everybody lives in the suburbs and avoids the cities. That is certainly true in most American cities.

John Trigge
April 2, 2011 9:43 pm

As a young lad (1950-1960) I lived in Byfleet, near Wisley.
Where we used to ‘taste-test’ corn and apples that grew within walking distance in a semi-rural area is now covered in housing and the M25 motorway. From Google maps, it appears that a lot of that farming has disappeared – how has that changed the local environment?
A lot of that area is also now almost an outer suburb of London with the consequent increase in traffic.
(Almost) glad I now live in Oz but Julia(r) is making me think maybe I’m not in the Lucky Country any more.

Harold Pierce Jr
April 2, 2011 10:22 pm

AusieDan
Can we have a look-see at your data? Could you send it to AW so he post it here?

wayne
April 2, 2011 11:01 pm

AusieDan says:
April 2, 2011 at 8:20 pm
UHI at Observatory Hill has a trend change impact on measured temperature which steadily increases each year in a linear fashion, most in winter and least in summer, which is also consistent with other comments to this post.

Thanks Dan. Australia and Oklahoma are probably very close to the same in growth patterns. In 1890 when temperature records began there were few towns. Even into the ‘50s you could drive around the state and most main streets were but a block long if that, now they tend to be ~25,000 population with some tall buildings WalMart’s parking lots, subdivisions, etc, etc.
Here the rural temperature trends look exactly as you described of Observatory Hill. Most of any upward trend is in the minimums and a tiny bit if any in the maximums. That is classic UHI. In the winter with much less energy within the cold atmosphere any man-made source affects it greatly. Not much in the summers with piping hot air everywhere anyway, what we might be adding is insignificant to temperatures. I’m speaking of towns, not large cities, they even show hikes in summer days.
Still, if those two, minimum and maximum, are ever averaged together, it appears as if all temperatures are going up and most people assume for some reason hotter summer days, not so, exactly the opposite, cold winter nights when warmer parking lots and structures release the heat gained in the day along with the heat pumped into the structures to stay warm. If the station is anywhere near this, and they usually are, you have UHI effect.
See, cities and rural small towns are somewhat different in UHI effect. That seems to be why Tulsa and Oklahoma City trends look so completely different than the 15 or so rural smaller towns sprinkled around. Anyway, that is what I have gathered after looking into it and what seems to explain it.
Dr. Spencer’s study of temperatures-to-population-density about a half a year ago really pegged this effect numerically.

geronimo
April 2, 2011 11:30 pm

RGates:
“James ibbotson says:
April 2, 2011 at 10:18 am
I’m thinking the entire so called 20th century slight warming is primarily due to UHI.
That’s a start on a running retreat IMHO…
___
Not likely.”
I have to agree with you firstly because I don’t believe this particular paper takes us down that route anyway, but primarily because the climate science community, or some part thereof, have dug a hole so deep for themselves by moving from the science into advocacy (and who knows what that’s done to the science?) that any retreat, or modification of their position, should they be wrong, is nigh on impossible. Moreover the wrath of the political classes will be visited upon them big time. So they have to dig in and hope they’re all dead before the enormity of what they’ve tried to do to becomes apparent.

Christopher Hanley
April 3, 2011 12:15 am

September 16, 2003 was a Tuesday, so it seems probable that the photo above was taken during the night or early morning hours because the City around St Paul’s and Whitehall/Westminster are cooler than the surrounding and outlying residential areas.

WAM
April 3, 2011 2:03 am

So, dr Jones starts to mention anti-ciclones. Slowly the theory of Polar Highs by late prof. Marcel Leroux begins – in a bit oblique way – emerge. A theory supported by a lot of observations. There are 2 books on AMAZON by prof. Leroux. Good eye opener when atmospheric circulation is considered (and deficiencies of its modelling).

PLS
April 3, 2011 2:15 am

>London’s population is still 500,000 less than 1938
Is that the population of London proper, or of the metropoltan area?
I think the only one that matters is the entire built-up area. I don’t think heat island effects respect city boudaries.

April 3, 2011 3:16 am

Anticyclones? UHI? so UHI is dependent on wind direction? Downwind is warmer, duh.
Misdirection. The core issue is integration of urban encroachment effects into the “trend”.

Ken Harvey
April 3, 2011 4:30 am

Stephen Brown says:
April 2, 2011 at 2:48 pm
“If I could harness that waste heat I’d be able to start seeds germinating in my poly-tunnel and greenhouse in January!”
I think that you would find, Stephen, that to progress from germination you would have to harness some other waste stuff such as sunlight or artificial ultraviolet light. Only Briffa and the tree ring brigade think that plants thrive on temperature alone.

April 3, 2011 5:34 am

Christopher Hanley says:
April 3, 2011 at 12:15 am
“September 16, 2003 was a Tuesday, so it seems probable that the photo above was taken during the night or early morning hours because the City around St Paul’s and Whitehall/Westminster are cooler than the surrounding and outlying residential areas.”
Not sure about that. I recall instruction from a seasoned glider pilot at High Wycombe that around late afternoon early evening (summer) it is possible to get weak lift of woods and lakes as the surrounding land cools. The exposed ground that was providing all the lift during the day will cool and continue doing so until it is cooler than the woods and lakes. At that point you get the lift of the woods. I have felt this lift and it only lasted about 30 mins, but it was weak. I would say this photo could still be around the middle of the day because 32C is quite warm, especially for September.
I wonder if the city is showing cooler because the tall buildings create sheltered ‘canyons’ particularly as the sun is not overhead at this time of year.

April 3, 2011 6:40 am

Is it possible the one of the “Fingerprints” used as proof of AGW, the fact that nighttime temperatures have increased more than daytime temperatures, actually be a fingerprint of UHI? I go into details of the logic of this at my website, http://socratesparadox.com/?p=195.

John F. Hultquist
April 3, 2011 7:35 am

eadler says:
~~~~April 2, 2011 at 8:23 pm
Doug S says:
~~~~April 2, 2011 at 2:05 pm
David Y says:
~~~~April 2, 2011 at 12:52 pm

Milankovitch cycles are given a new twist here:
http://motls.blogspot.com/2010/07/in-defense-of-milankovitch-by-gerard.html
If you search the site (the reference frame) with the term – milankovitch – there are additional results.

David Y
April 3, 2011 1:35 pm

re: eadler
Please drop the arrogance.
Finding info on Milankovitch Cycles is easy–it’s all over the place. Additionally, the websites you shared provide a view into the flipping of the climate ‘mode’, especially the departure from the dominant cool mode toward the interglacials. Great.
None of this–and this is where I am frustrated, because the current science doesn’t even fit the rigor my software customers require for business case justification of ROI prior to spending a chunk of dough on enterprise software–document or provide detailed models explaining details of the following:
1. A rate of ice accumulation and description–detailed–of how exactly the ice is accumulating. It’s not enough to simply say “well, less snow melts than freezes”. No sh_t Sherlock. Over what time scale does a continental ice sheet grow? Show me the calculations for ice accumulation, including changes (if any required) for rates of precipitation, rates of melt, etc. Explain the rate of advance.
2. A point of glacial genesis (other than ‘somewhere toward the poles’). If you track the retreat of the Wisconsinian glaciers in N. America, they withdraw to somewhere on/around Baffin Island. So let’s model where the ice accumulation happens. Is all the ice forming in a specific area? If the glaciers were plowing southward, this would indicate huge accumulation of ice/precip in a fairly localized area. Yes, melt & sublimation would be less than accumulation. But let me see someone model this.
3. What is happening with the climate elsewhere? Could this be like New Zealand, where it can be tropical/subtropical at the terminus of the glacier?
By simply pointing to Milankovitch Cycles, you’re taking the easy way out and skipping the details. I call that incomplete science. I know data is limited. So try a theory and support it with math.
DY

BillD
April 3, 2011 3:14 pm

When I mentioned that the biggest anomalies have been in the arctic, several readers suggested that camp fires and settlements are responsible for the anomalies in the arctic (e.g., northern Canada and Greenland). Can I then assume that campfires are responsible for the strong decline in arctic sea ice and evidence for melting of tunda across vast tracts of tundra in Alaska, Canada and Siberia? Is UHI responsible for the rather good agreement between surface temperatures and the satellite record? So far, all of the peer reviewed literature seems to say that UHI does not bias the surface record, including at least one publication based on data from Anthony’s surface statiobn analysis. I am looking forward to more journal publications on this topic.

Theo Goodwin
April 3, 2011 4:04 pm

John Trigge says:
April 2, 2011 at 9:43 pm
“As a young lad (1950-1960) I lived in Byfleet, near Wisley.
Where we used to ‘taste-test’ corn and apples that grew within walking distance in a semi-rural area is now covered in housing and the M25 motorway. From Google maps, it appears that a lot of that farming has disappeared – how has that changed the local environment?”
Roger Pielke, Sr., is your man. He has been researching UHI and land-use changes for several years and attributes considerable warming to them. Search on his name for his website.

BillyBob
April 3, 2011 8:03 pm

BillD: “Is UHI responsible for the rather good agreement between surface temperatures and the satellite record?”
I would disagree strongly that there is good agreement. I would suggest that when both satellite systems suggest it is no warmer than 1980, claiming that there is warming going on is misguided.
February 2011
Satellite
UAH : -0.018C
RSS: 0.051 C
Non-Satellite
NOAA/NCDC : .4042C
GISTEMP: .44C
HADCRUT: .267C

jorgekafkazar
April 3, 2011 8:26 pm

LazyTeenager says: “…And you did this in a car that had been standing in the sun all day AND at the time of day when the temperature is falling fast. I am the only person who sees something wrong with this?”
Yes. You are ignoring sensor placement relative to the vehicle and the fact that the vehicle was moving at speed limit. The car was moving fast enough that your other worries are of no consequence.

Scott
April 4, 2011 8:21 am

BillD says:
April 3, 2011 at 3:14 pm

When I mentioned that the biggest anomalies have been in the arctic, several readers suggested that camp fires and settlements are responsible for the anomalies in the arctic (e.g., northern Canada and Greenland). Can I then assume that campfires are responsible for the strong decline in arctic sea ice and evidence for melting of tunda [sic] across vast tracts of tundra in Alaska, Canada and Siberia?

BillD, I suggest you look up the definition of the logical fallacy known as a red herring…which is what your above discussion is. We aren’t arguing the sea ice and tundra melt here, and there are possibilities that these could happen without global warming, much less AGW or CAGW.

Is UHI responsible for the rather good agreement between surface temperatures and the satellite record?

I was unaware that the land-based temperature records agreed so well for the Arctic (I’d also argue that the more important factor is the temp at both poles, considering that both poles were the prediction of the climate models which you’re pointing to, but we’ll ignore that for now). Do you have data to back up the claim of good agreement in the Arctic?…I’d be curious to see it if you do. No, overall agreement for a global anomaly is not the same…and considering how different GISS has been this past decade relative to the other land-based records and the satellites, I don’t even know if your statement holds for the globe either.

So far, all of the peer reviewed literature seems to say that UHI does not bias the surface record, including at least one publication based on data from Anthony’s surface statiobn (sic) analysis. I am looking forward to more journal publications on this topic.

How many serious peer-reviewed inquiries into the subject have been performed using the complete data set? Data sets with only a fraction of the sites that have not been quality controlled don’t count.
-Scott

Scott
April 4, 2011 8:24 am

BillyBob says:
April 3, 2011 at 8:03 pm

I would disagree strongly that there is good agreement. I would suggest that when both satellite systems suggest it is no warmer than 1980, claiming that there is warming going on is misguided.
February 2011
Satellite
UAH : -0.018C
RSS: 0.051 C
Non-Satellite
NOAA/NCDC : .4042C
GISTEMP: .44C
HADCRUT: .267C

While I agree with you that the agreement is not as well as is often hand waved, are those anomalies using the same temporal base period? If not, that makes it an apples vs oranges comparison and therefore invalid. Once on the same base period, we should actually be discussing Arctic temps (or temps at both poles instead), because that’s what is under discussion.
-Scott

E.M.Smith
Editor
April 4, 2011 12:08 pm

Just look at the ‘speckle’ character of that photo.
Think about how poorly the air is integrating all those temperature variations.
So you can make a ‘trend’ by having your station in a ‘cool speckle’ in 1950-1980, then moving it to a ‘warm speckle’ just a few meters over…
It’s not just the overall UHI that matters, it is that you measure but a single point in that mess, and the point moves over time, as does some of the mess…

DirkH
April 4, 2011 12:27 pm

E.M.Smith says:
April 4, 2011 at 12:08 pm
“Just look at the ‘speckle’ character of that photo.”
Good observation. We know that temperature series are brown noise in the temporal dimension, so they’re fractal; probably the same applies in the spatial dimensions.

BillyBob
April 5, 2011 7:45 am

Scoitt: “we should actually be discussing Arctic temps (or temps at both poles instead), because that’s what is under discussion.”
There are very few arctic weather stations so most data is extrapolated (fabricated).
HADCRU is less out of whack because they fabricate less data than GISTEMP.

Scott
April 5, 2011 2:28 pm

BillyBob says:
April 5, 2011 at 7:45 am
Right, so can we compare the satellite results at more extreme latitudes with the GISS (or HadCRUT) ones? I know the satellites don’t get the poles, but it still might be a useful comparison.
-Scott