The Highest Temperature Reading Doesn’t Necessarily Mean a Record Hot Day

Guest post by Indur M. Goklany

On June 29th, the temperature at Reagan National Airport (DCA) in Washington, DC, hit 104 °F and it was duly noted by all and sundry that this was the hottest June day EVAH. Typical was the Washington Post story:

D.C. shatters all-time June record high, sizzles to 104

Mark Richards, weather observer at Reagan National Airport, says the temperature at 2:48 p.m. hit 104, blowing by the old June record of 102 set on June 9 in both 1874 and 2011. We are now experiencing D.C.’s hottest June temperatures in 142 years.

Indeed, 104 °F was the highest temperature ever measured in June in the vicinity of Reagan National Airport. But was it the warmest day in Washington, DC, ever?

This is what Reagan National Airport looks like in the present.

DCA_2011

Figure 1: Photograph from 2011. At left foreground is the Jefferson Monument. Behind it on the other side of the river, with the plane hovering over it is Reagan National Airport. Note the development, Crystal City, on the right hand side, also on the other side of the river.

But here is a photograph that shows us what this area look like a few decades ago.

DCA_1942

Figure 2: This picture, taken in 1942, shows the Jefferson Monument under construction. There is no Crystal City on the right, nor is there any Reagan National Airport. In fact, as one can see, that area was still being filled in. In the 19th century, the area occupied by the Memorial and adjacent land was also water, since much of this is also filled-in land.

Clearly, comparing temperature readings taken in 2012 at Reagan National against those taken over past decades at the same location is not an apples-to-apples comparison. That is, the data are not homogeneous. And whether the claim that June 29th, 2012 was the warmest Washington June day in 142 years is correct (or not), that claim cannot be supported by merely looking at the temperature readings at the airport.

The two degree difference between the previous record reading and the June 29th one may well be due to both the urban heat island effect and the “airport heat island effect,” a much understudied phenomenon (despite the fact that anyone who has stepped on asphalt in the middle of summer knows that the only thing worse is walking on coals).

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104°C? That’s hotter than the Sahara!
Surely it’s F, not C?
[REPLY: Fixed. Thanks. -REP]

Just remember while the AGW crowd will be bleating about the hottest year EVAH in the USA ask them about the record temperatures and drought in the UK as predicted by the Met office. They will be oddly silent.

In the UK we have been suffering torrential rain and storms and the period April to June has been one of the worst on record,
BBC report 29 June 2012
“Rainy weather breaks UK record for three months to June
April to June this year has been the wettest second quarter in the UK since records began in 1910.”
Yet the Met Office forecast for the periods seems out of line with reality.
Met Office 3-month Outlook
Period: May – July 2012 Issue date: 26.04.12
The forecast presented here is for May and the average of the May-June-July period for the United Kingdom as a whole. This forecast is based on information from observations, several numerical models and expert judgement. [My sarc “Expert Judgement?” ]
SUMMARY – PRECIPITATION:
For UK-average rainfall, the predicted probabilities slightly favour above-normal values during both May and May-June-July. However, confidence in this prediction is not high, and there is still a significant probability of below-normal rainfall. Whilst the wet weather of recent weeks will have had a positive effect on soil moisture, with all that that implies for agriculture, it is unlikely to have had a significant impact on groundwater supplies. With the forecast for May and May-June-July not favouring a continuation of the current very wet spell, groundwater resources in southern, eastern and central England are very unlikely to recover during this period.
The probability that UK-average rainfall for May-June-July will fall into the driest of our five categories is around 15%, whilst the probability that it will fall into the wettest of our five categories is around 30% (the 1971-2000 climatological probability for each of these categories is 20%).
Remember the March forecast:
Met Office 3-month Outlook
Period: April – June 2012 Issue date: 23.03.12
SUMMARY – PRECIPITATION:
The forecast for average UK rainfall slightly favours drier than average conditions for April-May-June as a whole, and also slightly favours April being the driest of the 3 months.
…….The probability that UK precipitation for April-May-June will fall into the driest of our five categories is 20-25%
And they say they need more money for a new computer?
“The Met Office needs new powerful computers to deliver extreme weather warnings, more accurate long-term forecasts and improved climate modelling, according to Parliament’s science and technology committee.” – The Guardian, that well known unbiased [sarc] reporter of climate change.

Horace the Grump

104C? You sure about that?
[REPLY: Fixed. Thanks. -REP]

Huub Bakker

Didn’t you see the steam rising off the river? 🙂

Jimbo

Typo???
“Indeed, 104 °C…..”
The linked to story does not mention 104 °C but 104
[REPLY: Obviously. Got it fixed, thanks. -REP]

Don Keiller

@Adrian, you have got it all wrong. Thwe very fact that the UK has had exceptionally wet weather, whilst Washington has had record high temperatures is simply proof positive that climatic extremes are on the increase, caused by increased CO2 (sarc).

Jimbo

Thanks Adrian Kerton. Now that June is over WUWT might want to re-visit the Met Office original forecast. This is one for the weather not climate fail files.

Rover Driver

104 C is above boiling point of water. Methinks something is wrong!
[REPLY: Well, he did say “…it was duly noted by all and sundry that this was the hottest June day EVAH…”It’s fixed! It’s fixed! -REP]

crosspatch

Looks to me like the temperature was more likely 102F. Looking at some locations surrounding Washington DC that haven’t really changed much over the past 50 years, all of those locations report 102F for that day. These are locations to the east, west, and north of DC.
Great Falls, VA, Frederick, MD, and Chestertown MD all report 102F.

crosspatch

Also, Upper Marlboro, MD which is basically straight East out of DC on Pennsylvania Ave was also 102F that day. So judging from the various locations around Washington all being 102F that day, I will go out on a limb and say DC was probably seeing 2 degrees of UHI.

ross-shire mannie

I’m sittin on my Big Tractor today playing with my new IT Gadget and the mobile internet:
“urban heat island effect and the “airport heat island effect,” ” Yes … now THAT is a kind of Manmade Global warming I can / could / do agree with: MAN _ MADE Politics interfering in our Agriculture = Carrot n Stick Politics – no longer mixed Agriculture – large scale ‘monoculture’ large areas of a particular crop at certain / the same time of year, = large areas with the same absorptive / reflective indices etc….fieldwater run-off, water absorption / CO2 release at night, etc etc ( leave that all for the good Botanists to elaborate upon..) ……. suffice to say , I have been in the fields long enough to tell the difference between patchwork smallish fields and large scale ( tho’ not Praire scale) to see the difference…….. Mid-morning Convective currents from low-wind weather causing us the grief whilst crop-spraying etc., Then the Lunchtime High winds and the similar early evening High winds following the daily Heating cycles from the hills around us too – Like the Tides…………. BUT! 🙂 we live where we work and see all this all the time – wot can we do about Nature – ’tis the Townee Scientists who tell us its AGW etc and Tax us something stupid to counter the effects….. Same old story… Spend more money to solve the problem ….Eh? Throughing money at anything never solved the problem. The little Dutch Boy just stuck his finger IN it ( probably never even occurred to him that he should have stuffed £ notes in the hole……. an’ how long would the paper have lasted ? DON’t even THINK about saying it would have “bought” = given him time to go and get help to stem the flow…. Dat’s wot I got a new4n 4 …….. – F the cld decy4 txt *%^&” datz Y the water condenses out of warm air: more trees around here and OSR too adding to Pollen levels – too late for the OSR Pollen now but Hey! its maybe the Barley Pollen – an awful lot of Cereals have come on very quickly despite the awful spring we’ve had – may be an early harvest after all..
Mus Shift – am parked in the way!

The comment about the UK forecast, April, May, June, by the UKMet. Office has been reported by Christopher Booker in today’s Sunday Telegraph. The forecast was 180 degrees wrong. Yet the computer models used for this disastrous result were the same as those used to forecast the climate/weather 100years hence and used by the IPCC. So what faith do we have in their cataclysmic scenarios of future climate change.

Tony B (another one)

Every time I drive past London Heathrow Airport, on the various local roads which get within a couple of hundred yards of the runways, my car’s external temperature reading goes up noticeably. Typically +2 deg C, sometimes as much as +4 deg C.
The preponderance of airport sited temperature records is the main reason for any statistical increase in “global” temperatures. Oh, and fiddling the present upwards, and the past downwards, and reducing the numbers of high latitude locations, etc etc…

GAZ

Or the coldest day in Melbourne in 17 yeas. But then, Australia now has a carbon tax, so there is a reason for the sudden cooling
http://www.weatherzone.com.au/news/melbourne-cracking-a-coldie/21999

Words such as “record” and “hottest” mean so little. The highest heat I have experienced in my part of Oz was in late summer 2004 (this was on the heels of the Big Heat in Europe in ’03). The worst heat, however, was when inland north westerlies combined with summer heat in the early 1980s and around the year 2000. This lethal pattern was first reported by very reliable naval officers in Sydney – in the summer of 1791-1792! Their description and temp readings would indicate that the Big Heat of that summer was worse than anything I have experienced. There were mass wildlife deaths, with parrots and bats dropping dead from the air. It is factors such as wind direction and how long the heat is sustained that matter, as much as a temp reading. Mind you, those 1791-2 temps were very high. (To further amaze, the most recent and best known editor of the journals which relate these weather events is…Tim Flannery! No joke!)
For what it’s worth, the coolest summer I ever experienced in my 63 years was the one just past. Which proves absolutely nothing.

michaeljmcfadden

What? Hot? 104 Kelvin? You call that HOT?????
– MJM

Mike M

“104°C? That’s hotter than the Sahara!”
It was just a prophetic slip of the tongue. That’s not the temperature at the location of where the politicians are right now – it’s the one at the location were most of them are are going to be later.
( Not fixed from what I’m seeing BTW. “Indeed, 104 °C was the highest temperature…”)
[REPLY: Drats! There were two of them! Fixed NOW. -REP]

BarryW

Add to that what you don’t see. Across the river is now Bolling Airforce Base and Blue Plains Sewage Treatment Plant, Naval Research Lab, and Southeast DC. Just beyond Crystal City is Alexandria and the Capitol Beltway. The road in the foreground is 395 (site of the infamous Florida Air 90 crash) which is a major commuter artery as is the GW parkway which runs next to the airport. In essence, the airport is in the middle of a city as opposed to the edge. In addition it sits on (in) the Potomac River which has to bias the temps just by the effect of the water. Snowfall is often measured as smaller than that reported in other nearby sites for example.

Mike M

Speaking of airports now even the FAA is foisting emission reduction bunk on us. This is the silliest thing I’ve ever seen from the FAA; enough even to make me afraid to fly… Ya’ll be careful up there! http://www.youtube.com/watch?v=Zfhh9xRauHk
Why not require airliners to keep their landing gear and flaps up until the last possible moment? That will save a LOT more emissions on approach than this idea.

“Puzzles are easier to solve when you have all the pieces: Fuel savings. Metric tons of CO2 emissions eliminated from the sky.”

http://www.faa.gov/NextGen/

“[REPLY: Well, he did say “…it was duly noted by all and sundry that this was the hottest June day EVAH…”It’s fixed! It’s fixed! -REP]”
No, the third paragraph has not yet been fixed.
[REPLY: It is now. Thanks. -REP]

Keith Pearson, formerly bikermailman, Anonymous no longer

.Never mind being barefoot on asphalt. Simply walk across a parking lot, then walk across a park. Then come back and tell me there’s only a .1 Degree UHI. Do it when it’s dark, tell me it’s not affecting nighttime temps. For that matter, even where there’s no concrete or asphalt, temps can vary with the presence of, or lack of, grass. Much of DC, and many urban areas, are let’s say…lacking in grass on their soil. There’s quite a difference in air temps depending on presence of grass, or hard packed dirt.
Interesting picture of DC. Also remember that historically, that area was a tidal swamp. Most of which has been filled in, creating more land use changes.

John M.

Hey, it still says “Indeed, 104 degrees C”.
Check all your data, not just some of it.
[REPLY: Yeah. Thanks. Fixed. -REP]

DEEBEE

WHat a wasted analysis. When a record is broken it is obvious it is due to global warming that too man-made. Keep these fossil fueled analyses to yourself. /sarc

Louise

Robbie

“a few decades ago”
2012 and 1942 means to Mr. Goklany a few decades ago. To me ‘a few’ means more than one, but certainly not more than five.
In the 70s and 80s it was cool in the forests and countryside during hot summerdays, but these days it’s just as warm and humid in forests as it is in towns and cities. At least in my country. There is no way to escape the heat anymore during hot summers. Why do you think the resulting thunderstorms have become so violent? It’s a strange thing that these violent thunderstorms do not form over cities, but over the “cooler” countryside.
Mr. Goklany: If the countryside was much cooler the thunderstorms would be milder in nature, but unfortunately they are not.
But OK let’s blame it on the UHI for that 2° temperature increase. In 70 years from now the increase may be 4-6° to 2012. Surely resulting in more violent thunderstorms. Are you then going to show us pictures about the situation in 2082 comparing it with 2012 too and blame it on the newly invented term ‘enhanced urban heat island effect’ (EUHI)?
And what about the situation in 2150 when temperatures are hotter if we go on with business as usual and superviolent thunderstorms have become the norm? Yet another new term: The ‘super enhanced urban heat island effect’ (SEUHI).

Jim R

About the Met Office here in the UK and their longer range forecasts. Do you folk know nothing of statistics and probability. Daily Mail journalists all of you? The Met Office offers probabilities of weather outcomes for the season ahead, based on seasonal records going back over centuries here in the UK. Bit like betting in many ways. When the fave for a race is stuffed by a hundred to one outsider it doesn’t happen very often. Twice in the last fifty years at the Grand National. So they say there’s an eighty percent chance of dry but there’s still a twenty percent chance of wet. Get over yourselves. Think about science and maths. I know there’s a problem with the Met Office for some of you folk here because it’s state owned. Would the RAF, The Navy, The British Army, British Airways and many others use it’s service if it was such a bunch of crap?

beng

Shocking, I say. Shocking. Back in the ’30s summer heatwaves (especially 1934), temps in downtown DC were well into the 100s, but they knew even then not to use those sites for records because they were obviously UHIE contaminated.

Frumious Bandersnatch

Er, fourth paragraph, it is still 104 C.
[REPLY: Missed that one. Fixed. -REP]

beng

BTW, it was 97F here in rural western MD. About the avg annual high for a typical summer. Next day (yesterday) the high was a comfortable 88F. The state heat record is in nearby Cumberland in 1934 at an amazing 109F. The same day in ’34 saw records of 110F+ in PA & WV.

Reblogged this on Climate Ponderings.

Steven Kopits

When Drudge has six stories on storms and record heat, I would expect to see similar coverage on WUWT. If it’s offset by record cold, that’s also news. The issue here is not ideology or cause, but simple newsworthiness.

John West

Even if it is the hottest in 142 years, is there something special about the last 142 years or even the last 1,420 years that makes it unusual over a geologically significant time scale?

Sal Minella

Let’s see.. If we have 200 years of acccurate temps for DC and the earth is 4,500,000,000 years old then, with .000004 % of the temperature data in hand and the rest unknown, we can use the term hottest ever, how?

We must remember that congress is in session. So that accounts for at least an extra two degrees of hot air.

“Every time I drive past London Heathrow Airport, on the various local roads which get within a couple of hundred yards of the runways, my car’s external temperature reading goes up noticeably. Typically +2 deg C, sometimes as much as +4 deg C.”
Yes, Everyday I leave town on a calm sunny day the temp drops about 4 F, as I pass the airport, the temp is always higher, then further from the heat island it is cooler. As soon as I leave the freeway another 4 F drop. I have observed any where up to 10 F drop in temp from town to home. The first 4 deg F are just outside the urban sprawl.
My point is the drama the news folks create regarding temperature readings, Extremism sells print.

Use a coin toss as a model for climate and weather. If you throw a lot of tails in a row it is cold, and a lot of heads in a row is hot. Most of the time, temperatures will be about average.
However, if you toss the coin long enough eventually you will toss 3 heads in a row. And if you continue to toss, eventually you will toss 4 heads in a row. And if you toss long enough you will toss 5 heads in a row. And if you continue to toss, you will eventually break this record as well. Over time every record hot and cold spell will be broken by a new record.
Question: is the coin (climate/weather) changing, so that it created more “record temperatures” when you toss? If the coin (climate/weather) isn’t changing, then how come you set new records the longer you toss the coin?

highflight56433

… and people were boiling their potatoes in the streets as mandated by law to conserve electricity when temperatures surpass 100 C as noted in paragraph three…104 C… 🙂
(its a cruel world)
[REPLY: Sorry, missed that one. Fixed. Thanks. -REP]

Steven Kopits says July 1, 2012 at 5:48 am
When Drudge has six stories on storms and record heat, I would expect to see similar coverage on WUWT. If it’s offset by record cold, that’s also news. The issue here is not ideology or cause, but simple newsworthiness.

What?

Mike Bromley the Kurd racing around Europe

Robbie says:
July 1, 2012 at 5:07 am
“In 70 years from now the increase may be 4-6° to 2012. Surely resulting in more violent thunderstorms. Are you then going to show us pictures about the situation in 2082 comparing it with 2012 too and blame it on the newly invented term ‘enhanced urban heat island effect’ (EUHI)?”

I think you left out the /sarc.
Or at least it SOUNDS like you did. In 70 years from now, a lot of things ‘may’ happen. You might even be clarvoyant by then. But I don’t think so. UHI wins, no matter how many sarcastic prefixes you add to the original abbreviation.

What the AGW faithful do not understand is that setting record temps is an accounting issue, and nothing to do with the temperature getting hotter. Even assuming the 140 year record history, that is no were near enough time to fill in all possible slots of temps. On the first day that temperature records are started, every day is a record breaking day, then as the years pass, those number of record breaking days drops off in a decay curve. Thus if you look at the number of record breaking days and count them for each year, you will find the bulk of them are in the beginning of the 1900’s. And it would take more than 3000 years to finally get to the point of no more record breaking days. For example, if the possible range of temps on July 1 at any given location is between 20 and 40C, and we measure in 1/10’s of a degree, then that is 200 possible slots. Times 365 days and the number of possible record breaking days to fill in is enormous, thousands of years to fill them all in, without an increasing temperature.

Keith Pearson, formerly bikermailman, Anonymous no longer says:
July 1, 2012 at 4:11 am
Also remember that historically, that area was a tidal swamp. Most of which has been filled in, creating more land use changes.

They didn’t fill it in enough — the place still attracts the bottom feeders…

Steve in SC

Back in the 80s or early 90s, don’t remember exactly which year, it was over 100 deg F in Columbia, SC for 26 straight days. We are talking 70% + RH so it was indeed miserable.

timetochooseagain

An important point to keep in mind: monthly averaged data generally undergoes the “adjustment” process that allegedly removes urban effects etc. (probably not all that effective, really) but daily data don’t receive this treatment. So looking at record braking dailies will inevitably mislead you, especially because of urbanization.

Arfur Bryant

[Jim R says:
July 1, 2012 at 5:19 am]
[“Would the RAF, The Navy, The British Army, British Airways and many others use it’s service if it was such a bunch of crap?”]
Jim, there is a world of difference between the ‘weather’ forecasting talents of the hundreds of (generally) good forecasters who work for the Met Office around the UK issuing forecasts on a daily basis to the services you quoted, and the complete buffoons who try to issue ‘climate scare’ predictions based on complex computer models fed rubbish data by people who have a vested interest in continuing a totally unjustified belief that a minor trace gas can cause a significant change in the Earth’s climate!
I have been listening to the genuine forecasters for over thirty years. Some are good and some are not so good. It would not be a lie to say that the “RAF, [Royal] Navy and British Army” etc take note of the forecasts but do not assume they are 100% correct. Many years ago (80s?), there was an excellent cartoon by ‘Tugg’ (bless him) – a brilliant cartoonist who specialised in Royal Navy Flight Safety cartoons – who portrayed a Squadron briefing room on board a ship where the Met Officer was giving a met briefing dressed in shorts, sunglasses and a Hawaiian shirt and, unseen behind him, the Commander Air was walking into the room covered in snow with a scowl on his face! It appears that Tugg was more than a little prescient about the state of ‘climate forecasting’ in the Met Office! 🙂
I am pretty sure that many, if not most, meteorologists working for the Met Office cringe with embarrassment when they read the climate predictions issued in their name…

Assuming there is no foul play with the data coming from Virginia, (????- Mann???)
looking carefully at all the data from the weather station at Reagan airport, I note it follows closely those of NY Kennedy airport.
For the results of New York, see
http://www.letterdash.com/henryp/global-cooling-is-here
Note that there is a sharp warming trend evident there over the past 12 years.
I should hasten to tell you that this warming is local and probably only applies to some parts of the west coast of the USA and Norway. Global cooling is still happening and it is still very real.
It seems to me that due to the fall in global temperatures, parts of the world are just getting some benefit of more clouds and more condensing water vapor, trapping some heat. Perhaps some more warmer on-shore wind may also be caused by the colder sun. There could be other factors causing some local warming due to a cooling earth.
However, these countries must not think they are safe from the cold that is coming.
Average temps. in Washington DC Reagan airport have actually started falling slightly since 2005 (looking only at all the data for the period 2005-2011, compared to the average for the same period 2005-2011).
Earth’s energy store is still very big, but eventually we are going to play catch up with falling maximum temperatures.

Average temps. in Washington DC Reagan airport have actually started falling slightly since 2005 (looking only at all the data for the period 2005-2011, compared to the average for the same period 2005-2011).
Sorry, that should read:
Average temps. in Washington DC Reagan airport have actually started falling slightly since 2005 (looking only at all the data for the period 2006-2011, compared to the average for the same period 2006-2011).

@ Jimbo
Thanks Adrian Kerton. Now that June is over WUWT might want to re-visit the Met Office original forecast. This is one for the weather not climate fail files.
Stay tuned, Jimbo. The Met usually take a week to get their numbers together. I’ll be knocking up a post then.

If the EPA can lower the temperature of the globe then cooling down an airport shouldn’t be a problem. EPA documentation accompanying proposed greenhouse gas emission regulations states that it’s regulations will reduce the average global temperature by ’0.006 to 0.0015C by 2100.’ The mathematical precison of the government science authoritarians of global warming is astounding! We should insist on this kind of precision in economics–e.g., dead and dying Old Europe will go bellyup in 104 days, 4 hours, 23 minutes and 7 seconds.

Dave Worley

“Sal Minella says:
July 1, 2012 at 6:19 am
Let’s see.. If we have 200 years of acccurate temps for DC and the earth is 4,500,000,000 years old then, with .000004 % of the temperature data in hand and the rest unknown, we can use the term hottest ever, how?”
Even if you only take the 6000 years during which civilization has flourished, you get a very insignificant 3.3%.