Flashback: U.S. Data Since 1895 Fail To Show Warming Trend

Here’s a blast from the past. Dr. James Hansen’s view in 1989 seemed a lot more temperate than it does today. Back then, he’s ready to accede to a study that says something counter to what his theory predicts, saying “I have no quarrel with it”. Today, he uses labels like “deniers” (see here) when such contradictory essays and facts are made public. What a difference 20 years makes.

And even back then, with no firm evidence in hand, Gore was pushing to cede White House environmental policy to “world policy”.


January 26, 1989

U.S. Data Since 1895 Fail To Show Warming Trend

By PHILIP SHABECOFF, Special to the New York Times
Correction Appended

WASHINGTON, Jan. 25— After examining climate data extending back nearly 100 years, a team of Government scientists has concluded that there has been no significant change in average temperatures or rainfall in the United States over that entire period.

While the nation’s weather in individual years or even for periods of years has been hotter or cooler and drier or wetter than in other periods, the new study shows that over the last century there has been no trend in one direction or another.

The study, made by scientists for the National Oceanic and Atmospheric Administration was published in the current issue of Geophysical Research Letters. It is based on temperature and precipitation readings taken at weather stations around the country from 1895 to 1987.

Dr. Kirby Hanson, the meteorologist who led the study, said in a telephone interview that the findings concerning the United States do not necessarily ”cast doubt” on previous findings of a worldwide trend toward warmer temperatures, nor do they have a bearing one way or another on the theory that a buildup of pollutants is acting like a greenhouse and causing global warming. He said that the United States occupies only a small percentage of Earth’s surface and that the new findings may be the result of regional variations.

Readings taken by other scientists have suggested a significant warming worldwide over the last 100 years. Dr. James E. Hansen, director of National Aeronautic and Space Administration’s Institute for Space Studies in Manhattan, has reported that average global temperatures have risen by nearly 1 degree Fahrenheit in this century and that the average temperatures in the 1980’s are the highest on record.

Dr. Hansen and other scientists have said that that there is a high degree of probability that this warming trend is associated with the atmospheric buildup of carbon dioxide and other industrial gases that absorb and retain radiation.

But other scientists, while agreeing with this basic theory of a greenhouse effect, say there is no convincing evidence that a pollution-induced warming has already begun.

Dr. Michael E. Schlesinger, an atmospheric scientist at Oregon State University who studies climate models, said there is no inconsistency between the data presented by the NOAA team and the greenhouse theory. But he said he regarded the new data as inconsistent with assumptions that such an effect is already detectable. More Droughts Predicted

Many of the computer models that predict global warming also predict that certain areas, including the Midwest in the United States, would suffer more frequent droughts.

Dr. Hanson of NOAA said today that the new study does not in any way contradict the findings reported by the NASA scientists and others. He said that his study, in which he was joined by George A. Maul and Thomas A. Karl, also of NOAA, looked at only the 48 contiguous states.

Dr. Hanson said that global warming caused by the greenhouse effect might have been countered by some cooling phenomenon that has not yet been identified and that the readings in his study recorded the net effect.

”We have to be careful about interpreting things like this,” he said. What About Urbanization? One aspect of the study that Dr. Hanson said was interesting was the finding that the urbanization of the United States has apparently not had a statistically significant effect on average temperature readings. A number of scientists have theorized that the replacement of forests and pastures by asphalt streets and concrete buildings, which retain heat, is an important cause of rising temperatures.

Dr. Hansen of NASA said today that he had ”no quarrel” with the findings in the new study. He noted that the United States covered only 1.5 percent of Earth. ”If you have only one degree warming on a global average, how much do you get at random” when taking measurements in such a relatively small area, he asked rhetorically.

”We are just arguing now about whether the global warming effect is large enough to see,” he added. ”It is not suprising we are not seeing it in a region that covers only 1.5 percent of the globe.”

Dr. Hansen said there were several ways to look at the temperature readings for the United States, including as a ”statistical fluke.”

Possibililty of Countereffects

Another possibility, he said, was that there were special conditions in the United States that would tend to offset a warming trend. For example, industrial activity produces dust and other solid particles that help form liquid droplets in the atmosphere. These droplets reflect radiation away from Earth and thus have a cooling influence.

Dr. Hansen suggested that at some point there could be a jump in temperature readings in the United States if the measurements in the new study were a statistical aberration or the result of atmospheric pollutants reflecting heat away from Earth. He noted that anti-pollution efforts are reducing the amount of these particles and thus reducing the reflection of heat.

Several computer models have projected that the greenhouse effect would cause average global temperatures to rise between 3 and 8 degrees Fahrenheit in the next century. But scientists concede that reactions set off by the warming trend itself could upset these predictions and produce unanticipated changes in climate patterns.

Legislative Action Sought

Coincidentally with the new report, legislation was introduced in the Senate today prescribing actions for addressing the threat of global warming. Senator Al Gore, Democrat of Tennessee, introduced a bill that calls for creating a Council on World Environmental Policy to replace the White House’s Council on Environmental Quality. This change would emphasize the international aspects of environmental issues.

The bill would also require a ban on industrial chemicals that not only are depleting the atmosphere’s ozone layer, which blocks harmful ultraviolet radiation, but are believed to be contributing to the warming trend. It would also require stricter fuel-economy standards for automobiles to reduce the consumption of gasoline to reduce carbon dioxide.

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kevin

Priceless…
Hansen: ”We are just arguing now about whether the global warming effect is large enough to see,”…

Mooloo

Many of the computer models that predict global warming also predict that certain areas, including the Midwest in the United States, would suffer more frequent droughts.
Has this turned out to be accurate?

GAZ

“Dr. Hansen and other scientists have said that that there is a high degree of probability …”
Which sounds a bit less confident than
“Very high confidence…” in AR4
Are they mellowing?

richard

As the American are fond of saying, ‘what a crock!’
No warning trend found so lets blame some ‘unknown’ forcing factor.
If this study had found any warning trends, you can bet your bottom dollar that the story would have been a straight ‘warming found’ piece.

R. de Haan

That’s how a hoax in the public domain is started.
What was the name of the newspaper again?

Gareth Phillips

I note the Arctic ice has stopped expanding, maybe to show we sceptics are objective and even handed this should be highlighted.
http://nsidc.org/data/seaice_index/images/daily_images/N_timeseries.png

Jimmy Haigh

Mooloo (00:24:39) :
“Has this turned out to be accurate?”
I doubt it.

Tor Hansson

The U.S. is the country with the best data set available, and it’s not that small a place. To assume that a global phenomenon somehow “skips” the United States seems far-fetched, and without good reason it is a frivolous contention.
That the United States with its fuel-burning, urbanizing ways should not show a UHI effect gives pause. What happened to that? Is it really aerosols? Or is there really cooling, as seen in many rural stations, neutralized by UHI in others?

JMANON

QUOTE:
Dr. Kirby Hanson, the meteorologist who led the study, said in a telephone interview that the findings concerning the United States do not necessarily ”cast doubt” on previous findings of a worldwide trend toward warmer temperatures, nor do they have a bearing one way or another on the theory that a buildup of pollutants is acting like a greenhouse and causing global warming. He said that the United States occupies only a small percentage of Earth’s surface and that the new findings may be the result of regional variations.
END QUOTE
That wording is highly illuminating.
US weathar just a regional variation? Small part of the earths surface?
Yeah, what he is saying is “Please don’t hit me, I just had to get my report published and I’m trying not to say up front that AGW is rubbish.”

Mike Haseler

Newsflash: SS Global Warming is sinking
(Off Topic, but still worth it.)
Over the last few years, the average google hits for news on either global warming or climate change has been around 13,667, reaching an all time peak in Dec 2009 with 23,800 news stories in that month.
In Jan 2010 that figure sharply declined from those at the end of 2009 when climategate was fresh to 14,200. But last month (Feb 2010) that figure crashed to 2790. That is a massive drop to 20% of “average”. It’ has not been so low since Feb 2004 in terms of the number of hits, but as many more media have gone on-line in that period the it is more like it was in 1995 in terms of percentage of the news. (Based on the scale used by google, which I assume is a scale with relative percentage of all news story hits)
Moreover, the type of story has also dramatically changed. Before climategate it was common to search 50 or so stories and not find one with a proper scientific scepticism. I would now say as a rough rule of thumb, that there is just a majority of news stories that are sceptical. More importantly, the kind of news story that used to be the cheap fillers between serious news: “the global warming could ..” prefix to any research which the University hoped to get publicity for by linking it with the kudos of global warming, is now a very rare exception.
So at a rough estimate, the percentage “pro” stories has fallen by something like 90%. The percentage of “pro” stories from the general academic research community has probably fallen by another order of magnitude.
Late me state that again: the MSM support for global warming (propaganda) is now at 10%, of the average value in the last few years.
This really is like sitting on the coast in Indonesia and suddenly watching the publicity tide going out from the beach leaving global warming fish flapping in little pools isolated from the sea. What do we do next? Go down onto the beach and pick up the fish and eat them for supper? Lift up our King Canute deck-chairs and go home with a job well done?
See: http://news.google.co.uk/archivesearch?q=%22climate+change%22+OR+%22global+warming%22&scoring=a&hl=en&ned=uk&um=1&sa=N&sugg=d&as_ldate=2010/02&as_hdate=2010/02&lnav=hist1

toyotawhizguy

@Mooloo (00:24:39) :
“Many of the computer models that predict global warming also predict that certain areas, including the Midwest in the United States, would suffer more frequent droughts.
Has this turned out to be accurate?”
Certainly not in 2008.
See: MIDWEST FLOOD RESPONSE AND RECOVERY
Link: http://www.usa.gov/flooding.shtml

Stephan

Gareth Phillips (01:00:09) :
JAXA
I note the Arctic ice has stopped expanding, maybe to show we sceptics are objective and even handed this should be highlighted.
http://nsidc.org/data/seaice_index/images/daily_images/N_timeseries.png
I don’t agree with that graph from NSDC, it being fabricated for the AGW agenda,,, have a look at DMI, NORSEX , JAXA. Cryosphere today has been known to constantly change the NH picture to suit the AGW agenda as well
Im sick and tired of these people, no longer time to be nice to them… refer toclimategate and IPCC LOL
http://ocean.dmi.dk/arctic/icecover.uk.php
http://arctic-roos.org/observations/satellite-data/sea-ice/ice-area-and-extent-in-arctic
http://www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm

Slabadang

Well….. the truth was out there!
Watts, EM Smith,DÀleo,satellites, Willy Eisenbach,Monckton,Long ,Spencer,Lindzen,Pielke JR & Sr,McIntyre,Carter,Plimer,Karlèn and numerous other created an unorginazed pack of woodpeckers.Finnaly bringing this big rutten awful dangerous tree down!Mainstream media has made on an for trust and reability long slow harakiri! We will never forget whos to trust and whòs not!

Dirk

Depicting USA as 1,5% of the world is not true !!, it’s more than 2%
USA occupies 6% of worlds total land mass, so then it looks different with a stable temerature.

RichieP

OT
Credit Agricole have been reading their Mencken (“the whole aim of practical politics is to keep the populace alarmed (and hence clamorous to be led to safety) by an endless series of hobgoblins, most of them imaginary”) but not their WUWT:
[youtube=http://www.youtube.com/watch?v=ypjKxGCgO8E&hl=en_GB&fs=1&]

barbarausa

“Coincidentally with the new report, legislation was introduced in the Senate today prescribing actions for addressing the threat of global warming. Senator Al Gore, Democrat of Tennessee, introduced a bill that calls for creating a Council on World Environmental Policy to replace the White House’s Council on Environmental Quality. This change would emphasize the international aspects of environmental issues.”
What coincidence?
That is how a political PR campaign works.

Geoff Sherrington

Mike Haseler (02:52:23) : “Over the last few years, the average google hits for news on either global warming or climate change has been around 13,667, reaching an all time peak in Dec 2009 with 23,800 news stories in that month.”
It must be the way you do your search. Just now I did “climate change news” for 31.3 million hits and “global warming news” for 24 million hits. These come from Australia, using the button from Australia rather than Global. Can you be more explicit how you search?

Peter of Sydney

Let’s see. The climate scientists are panicking for detecting a rise of about 0.6 C over 100 or so years. Has anyone stopped to think such a rise is not even measurable over that time? It’s less than the noise level and the amount one would expect from natural variability. So why the panic? Where’s the catastrophic warming? Obviously there isn’t any. As for predicting the future using computer models of climate change – we all know they are just wild guesses and are useless. I can already see in the decades to come how all the AGW alarmists will be considered to be fraudsters and hoaxes at best, and corrupt and grimy individuals at worst who deserve to be behind bars.

toyotawhizguy

@ jbrodhead (01:45:13) :
“Here’s an article a FB friend just posted…
http://www.alternet.org/environment/145838/how_the_mountain_of_climate_change_evidence_is_being_used_to_und
That article is written by Bill McKibben. Obviously the author takes that “Mountain of Climate Change Evidence” as gospel, and is unwilling to recognize how the science has been corrupted by politics, as well as the skewing and cherry picking of data, the uncertainty of the AGW hypothesis, the complexity of the Climate, the unreliability of proxy data, the gross exaggerations and unproven claims regarding how much increased CO2 will affect the climate, the infancy of Climatology, that correlation is not proof of causation, the fallibility of climate computer models (can’t even reliably predict last week’s weather), the reliance of Climate researchers on “one sided” grant funding, the rigging of the peer review process, the motivations of the UN /IPCC (just Google “Maurice Strong”), the lies and distortions contained in “An inconvenient Truth”, the history of natural climate change going back millions of years, AND the mountain of counter evidence. Did I miss anything? McKibben’s article is hardly fair and balanced. Rather than we AGW skeptics having an “OJ Moment” as suggested by McKibben, the warmists have been having a 20 year “Cardiff Giant” moment.

Uh, the commenters here do realize that the article is from 1989, right?

Robinson

In other news, child survives bullet in the chest after parents kill themselves over Global Warming fears.
I’m sure someone has pointed this out before: it’s a kind-of mental disorder, isn’t it?

richard

completely o/t but over the road from me is a “zero-emission” electric van on charge, plugged into a mains outlet.
Am I the only one that sees something wrong with this kind of mindless greenwash? Yes, the vehicle doesn’t emit but I’ll bet the coal-fired power station it’s plugged into does.

Mark

I wonder if there was no warming trend because they hadn’t yet ‘added value’ (massaged) to the data…

Jeff Kooistra

Hmmm — no warming up until 1989 or so. No warming from 1995 to the present as admitted by Jones. Must be one hell of a spike there between 89 and 95 then — anyone see it?

hunter

This essay was before GISS had ‘clarified’ the record, and before the hockey sticks had been ‘discovered’.
On a serious note, I think the history will show that in the El Nino year of 1998, Hansen and the politicians decided that what they thought saw was *proof* of AGW calamity and flipped right about then from simply scientists and advocates into fear mongers and charlatans.
All for the best of reasons (in their minds).

johnnythelowery

As there has been no warming prior to 1989 according to Hanssen(Thankyou Dr. Hanssen!) and there has been no warming since 1995…..so, we have a window of 6 years where the Science isn’t settled but otherwise we all agree. But what ever happened between those years(nothing), everything returned to normal by 1995. This is a very damning article with Gore already throthing at the mouth with all the cash that can be made and power he can garner without the slightest piece of science to stand on.

Joe

There are a great many variables to knowledge of even how climate interacts.
Temperature reading are effects along with increased precipitation are effects.
The climate models will always be wrong as not all the variables will have been thought of to put in.
Our own arrogance that the theories we have now is 100% correct will be civilizations downfall.
Very few people on this planet have a very good understanding of how this planet actually works. Why?
Too many people believe what ever is written must be true.
Our understanding of science is so backward that it totally misses the mark of the achievements this planet went through to adapt and change to give us the balance we see today.
Darwin did not go deep enough! Similar plant and animal life evolved differently when the land masses broke apart and became separate isolation areas. This is only one variable.

johnnythelowery

……………………………Slabadang (02:56:23) : Well….. the truth was out there!
Watts, EM Smith,DÀleo,satellites, Willy Eisenbach,Monckton,Long ,Spencer,Lindzen,Pielke JR & Sr,McIntyre,Carter,Plimer,Karlèn and numerous other created an unorginazed pack of woodpeckers.Finnaly bringing this big rutten awful dangerous tree down!Mainstream media has made on an for trust and reability long slow harakiri! We will never forget whos to trust and whòs not!
I’d like to add that Roll:
Professor Tim Ball – Dept. of Climatology – Uni. Winnipeg
Professor Nir Shaviv – Institute of Physics – Uni. Jerusalem
Professor Ian Clark – Dept. Earth Sciences – Uni. of Ottawa
Dr. Piers Corbin – Weather forecaster – Weather Action
Professor John Christy –
Professor Philip Stott – Dept. of Biogeography – Uni. of London
Professor Paul Reiter – Pasteur Institute, Paris
Patrick Moore – Greenpeace
Dr. Roy Spencer – Weather Satelite Team Leader – NASA
Nigel Calder – New Scientist
Prof. Syun Ichi Akasofu – Director – International Arctic Research Unit
Martin Durkin – WagTV –
These guys came out infront of the cameras and said it how it is. I noticed there were only 4 comments in 3/2007 after the showing of the
‘Great Global Warming Swindle’ documentary and I don’t know why that is as I consider this the greatest, most important documentary ever made. (9 parts available over on Youtube).

What a difference 20 years makes.
Why is that surprising, exactly?
There’s a huge amount of data that’s been collected in the past twenty years showing a clear warming trend, to the point that even a certain Mr Anthony Watts says that “Nobody I know of in the sceptic community denies that the earth has gotten warmer in the past century. I surely don’t.”

Eddie

Wow talk about Déjà Vu. This sounds identical to what we hear from the IPCC everyday. “This is the hottest decade ever…more severe weather, more droughts, more famine…”
On another note, I found this paragraph to be rather amusing. Can we say, ‘water vapor’?
“Another possibility, he said, was that there were special conditions in the United States that would tend to offset a warming trend. For example, industrial activity produces dust and other solid particles that help form liquid droplets in the atmosphere. These droplets reflect radiation away from Earth and thus have a cooling influence.”

R. de Haan

Global Warming Alarmed Parents kill their children and commit suicide!
Victims of an MSM pushed religion? I think they are simply plain crazy.
http://motls.blogspot.com/2010/03/global-warming-alarmed-parents-murdered.html?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+LuboMotlsReferenceFrame+%28Lubos+Motl%27s+reference+frame%29

Pamela Gray

NOOOOOOOO! Not my Sean!!!!!!!!!!! Baby, what were you thinking?????

R. de Haan

The end of the scare!
State of fear, not!
http://eureferendum.blogspot.com/2010/03/state-of-fear-not.htm

Steve Keohane

Dr. James E. Hansen, director of National Aeronautic and Space Administration’s Institute for Space Studies in Manhattan, has reported that average global temperatures have risen by nearly 1 degree Fahrenheit in this century and that the average temperatures in the 1980’s are the highest on record.
Must have been before he figured out the 30s were the warmest, then ten years later he figured out how to lower the past and make the 90s the hottest.

Mike Haseler

Geoff Sherrington, you need to search news stories for Global Warming, and not every webpage for News + Global + Warming. The difference (if not obvious) is that the searches for news are limited to news sites and e.g. don’t include this website.
The link I posted should get you straight to correct search.
Alternatively, go to google, search “global warming”, click the option at the top for “news”. This takes you to http://news.google.co.uk ( http://news.google.com.au for you)
Then down the left select a date like 2007, and then navigate by clicking bar chart.
Alternatively in Australia just click:
http://news.google.com.au/archivesearch?q=%22global+warming%22+OR+%22climate+change%22&scoring=a&hl=en&ned=au&um=1&sa=N&sugg=d&as_ldate=2010&as_hdate=2014&lnav=hist6

Herman L

“What a difference 20 years makes.”
Over five thousand peer-reviewed scientific papers (and that’s only counting those cited in the IPCC FAR) did not exist twenty years ago. That’s the difference.

blcjr

Did I miss an explanation for why the period of coverage ends in 1987? The fact that they start with 1895 could mean that they used USHCN data, or perhaps the regional or state composites. But that data is available up to the present. Why did they stop in 1987?

Mick J

Off topic but timing is all. BBC have announced that Phil Jones will be being interviewed by the Parliamentary Committee investigating climategate today.
Being carried live at http://news.bbc.co.uk/democracylive/hi/house_of_commons/newsid_8542000/8542836.stm
Don’t know if viewable outside of the UK.
Coverage starts at 3pm GMT. Five hours ahead of US EST I think.

Nick

“Dr. Hansen of NASA said today that he had ”no quarrel” with the findings in the new study. He noted that the United States covered only 1.5 percent of Earth. ”If you have only one degree warming on a global average, how much do you get at random” when taking measurements in such a relatively small area, he asked rhetorically.
”We are just arguing now about whether the global warming effect is large enough to see,” he added. ”It is not suprising we are not seeing it in a region that covers only 1.5 percent of the globe.””
This doesn’t sound scandalous – it sounds like Jones did in his interview with the BBC – an honest answer that could easily be spun by some folks.

JonesII

If somebody were to conduct a police investigation, 1989 was the year IT began.

Don Shaw

As of Jan 1989 acording to Hansen
“After examining climate data extending back nearly 100 years, a team of Government scientists has concluded that there has been no significant change in average temperatures or rainfall in the United States over that entire period.”
As of Feb 2010
Acording to Jones: There has been no significant warming since 1995.
Ergo all the warming claimed by Gore, Obama, and Boxer occurred in the 6 years between 1989 and 1995. Having lived through that period, what did I miss?

PeterB in Indainapolis

In reply to Gareth Phillips,
Normal cyclical variations in Arctic ice-cover are, well, normal.
No skeptic claims that the arctic ice-sheet will be ever-expanding! If that were the case, it would be disasterous.
Relatively warm water quite a bit farther north than “normal” is perfectly “normal” for a winter with a strong El Nino. I would assume that this would have some effect on the arctic ice-sheet.
The default position for the vast majority of skeptics is not that the Earth never warms, that would be silly. We do not advocate for continual ice-ages. The default position for most skeptics is, “The earth warms (sometimes dramatically) and cools (sometimes dramatically) quite often when measured on a geological time-scale, and the current trend is in no way out of the ordinary when compared to other past climate variation.

A team of scientists has concluded… that there has been no significant change in average temperatures or rainfall [USA, 1895-1987]
– Dr. Kirby Hanson .. said in that the findings concerning the United States do not necessarily ”cast doubt” on previous findings
– Dr. Michael E. Schlesinger said there is no inconsistency between the data presented by the NOAA team and the greenhouse theory. But he said he regarded the new data as inconsistent with assumptions that such an effect is already detectable
– Dr. Hanson of NOAA said today that the new study does not in any way contradict the findings reported by the NASA scientists and others
– Dr. Hansen said there were several ways to look at the temperature readings for the United States, including as a “statistical fluke”
Oh my. Is there any kind of measured data, which “do not contradict”, “cast no doubts” or “are not inconsistent” with the AGW theory?
“Several ways to look at the temperature readings” by Dr. Hansen is very telling.

blcjr

Okay, Duh…
I missed that the “flashback” here is that this NYT piece was published in 1989.
I wonder what it would show if the same study were done today?
My guess: slight warming, but only because of the warming associated with th 1997-98 super El Nino, and the fact that trends are sensitive to outliers at the ends of the periods.

Steve Goddard

Prior to the year 2000, USHCN data showed no warming trend and the 1930s was the hottest decade. The USHCN adjustments made in 2001 bumped up all recent years – and magically a warming trend appeared.
[youtube=http://www.youtube.com/watch?v=oNI_devHg7w&hl=en_US&fs=1&]

Gerald Machnee

Can we do a study for the rest of the world so we do not have to stick to 1.5 percent?
Or are we lacking data?

Harold Vance

I don’t think that our knowledge of the earth’s climate is all that much better than it was in 1989. This is not to say that it’s not worth the effort to figure out what’s going on.
Has our ability to forecast short-term climate (weather) improved significantly (by orders of magnitude) since 1989? I just don’t think so.

Vincent

“Another possibility, he said, was that there were special conditions in the United States that would tend to offset a warming trend.”
Yeah right. We’re now forced to argue for special conditions and magic to try and fit the AGW theory to observations. I can see exactly what they mean by Post Normal Science.

Quote: “A number of scientists have theorized that the replacement of forests and pastures by asphalt streets and concrete buildings, which retain heat, is an important cause of rising temperatures.” Unquote
Is this supposed to be a reference to the Urban Heat Island Effect? If so, the writer does not understand the issue.
What a number of scientists are concerned with is that the thermometers used to measure the temperature of a region may be showing temperatures that are biased upwards because the thermometers are sited in urban hotspots.
These same sites were once cooler because the locations were in rural. The thermometers now register higher temperatures, not because the whole region is warmer, but because the thermometer location has become urban.
The rise in temperature at the thermometer site was caused by local heating, not by regional climate change.