How not to measure temperature, part 86: when in Rome, don’t do as the Romans do.

This is a preliminary post to a much more detailed one coming from my friend Paolo Mezzasalma. who is doing a tour of Italy’s weather stations.

While there are significant and systemic problems with USHCN stations in the United States, there are also problems with stations worldwide. One of the problems is that a good percentage of GHCN stations are at airports. For example, Paolo sent along a photo of  the weather station  at the Ciampino Airport in Rome, Italy. It piqued my interest for obvious reasons.

rome_italy_airport_weather_station

The arrows point to three different weather stations. two are Stevenson screens, the third is an automated “ASOS” like weather station presumably used for aviation weather. Note the proximity to the parked jets and tarmac.

Paolo writes:

“You see two Stevenson screens: the official one to the East and an automatic Data Collection Platform to the West, which was added recently.”

But that’s not all, this weather station site has other heat islands nearby, like a nice semi truck parking lot. That’s always good for a warm boost.

Click for larger image

Rome airport weather stations looking north - Click for larger image

In fact this weather station is caught between two modes of transportation. Trucking and aviation. I wonder which affects it more? I wonder if the jet parking area and the trucking staging area were always there?

Note also the red/white striped light pole missing in the older photo at top, but present in the annotated photo. You can view that photo interactively here. The jet on the right is also missing. The differences in photos underscores the fact that airports are hardly static places, and expansions, improvements, and construction is the modus operandi at most airports today.

Here’s the view looking south.

rome_italy_airport_weather_station_large2

Here is the interactive view

I wonder how the jet blast affects the high temperature recorded at the airport weather station on certain days when they take it out for a spin? I wonder how much the tarmac adds, or the trucking parking lot adds? Or is it all swamped by Rome’s UHI?

UPDATE: for those that might question whether jet exhaust could reach the weather stations, this instructional video from United Airlines done at the San Francisco airport in 1993 might be helpful in visualizing the problem. (h/t to “Just want truth”)

The TV show Mythbusters also recently did a similar demonstration.

So what are we really measuring at those weather stations at Rome’s airport?

The ENVIBASE project reports:

In the [Rome] urban area, five meteorological stations continuously collect climatic data, such as temperature, relative humidity, wind velocity and orientation, rainfall intensity, atmospheric pressure, etc., and organised them in a database form.

Such stations are:

* Urbe Airport;
* Ciampino Airport;
* Rome-Eur (operating for the last three years);
* Collegio Romano (located in the historic centre of Rome and collecting data since 1782);
* Monte Mario (for a limited period of forty years).

So what we have at Rome’s Ciampino airport is in fact a climate station. I’ll have more on this and other weather stations in Italy soon.

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59 Responses to How not to measure temperature, part 86: when in Rome, don’t do as the Romans do.

  1. Billy Ruff'n says:

    “What are we really measuring in Rome?”

    Exhaust gas temperature of a jet engine is, say, 600C….distance to the MMTS (in the photo) is ~ 150 m directly in line with the engine exhaust…

    It’s anyone’s guess as to what we’re measuring in Rome, but it’s not a natural ambient air temperature.

  2. savethesharks says:

    Pictures do not lie. Nothing like photographic evidence of weather stations adjacent to heat islands. Well done.

  3. John F. Hultquist says:

    It is good to document all these things but they are no longer surprising. It is reasonable for airports to have the data on temperature and winds close to runways. Even so, one might think the weather stations would not be located directly behind revving jets. Only the pilots and flight control folks should make any use of these local numbers. When this information is scooped up to support the global warming issue fraud begins.

    Thanks to Paolo.

  4. D. King says:

    What a great post for Simon’s blog.

  5. Keith Minto says:

    Exhaust blasts would produce momentary peaks of climatically unrealistic temperatures which may or may be recorded. If recorded,the readout would be very interesting.
    If the prevailing winds were from the truck car park, then that would produce a more constant ‘heat island’ effect that would effect( with a slight time lag due to thermal gathering) daytime temperatures.
    Comparisons to nearby sites would be useful.

  6. John F. Hultquist says:

    Is it too soon to go off topic?
    Has anyone tried to assess the impact of the Mt. Redoubt eruption?
    There is a nice image from two days ago (3/26) — a brown ash cloud extending over the Cook Inlet. Either or both of the two volcanoes might yet explode so maybe the question is premature. Still, this is a nice image.
    http://www.avo.alaska.edu/image.php?id=17249

  7. Keith Minto says:

    I had more ‘Romeing’ success using Google maps.

    There is only one runway and the MMTS site, to be fair, is near the aircraft parking area and the aircraft were probably towed there.

    I could not discern a prevailing wind from the description given in the ENVIBASE site, perhaps wind direction is random and seasonal.

  8. J Campbell says:

    As mentioned by JFH airport weather is for aviation use. The key temperature data is that a few feet above the runway usually black tar. The temperature is used for every takeoff to determine both flight speeds and engine performance/setting. A few degrees can be the difference between a drama or disaster in the case of something like an engine failure.

    Wrong data (presumably data entry) is a leading suspect for EK407 at YMML last week where there was a tailstrike, tracks on the grass and the localiser antenna was cut off 50cm (20″) above the brick localiser building.

  9. Leon Brozyna says:

    So we’ve already seen the abysmal state of the USHCN. It appears this pattern may be repeated in other countries as well. Not only are so many stations located in urban areas where the UHI bias has an impact, but they’ve also got siting issues. Now all we need do is find out how much of the past century or so of warming is real and how much is due to UHI & poor siting.

  10. Mike Lorrey says:

    But Hansen and Mann are absitively, posolutely sure they are already accounting for heat islands…. and see nothing wrong with smearing anybody who thinks otherwise.

  11. deadwood says:

    John F. Hultquist (20:52:28) :

    The AVO also has some great video footage of lahars racing down the flank glaciers at Redoubt.

    Link: ftp://ftpext.usgs.gov/pub/wr/ak/anchorage/Parker/

  12. Neil Crafter says:

    While this off the immediate topic, I just wanted to mention a brief experience I had of UHI just a few days ago. I was working in Horsham, a medium sized country town in rural Victoria, Australia. It has a population of approximately 15,000. I had to drive back to Adelaide after a few days there, and left at 5.15am and the temperature on my car’s thermometer was 10 degC. As I drove out of Horsham into the surrounding rural areas the temperature steadily dropped, eventually settling on 6C. As I came up to the next small town Nhill it rose again back to 10C and then dropped again to 6C as I passed into the rural areas and rose again to 10C as I drove through Kaniva. Both Nhill and Kaniva are small towns of only 2000 and 1000 people respectively. This experience showed to me that UHI is real and significant – of the order of 4C – and appears applicable in even quite small towns of 1000 people. I suspect the difference in temperature from town to rural is more at certain times of the day, but nonetheless is significant. This sort of difference seems of a similar order of magnitude to Anthony’s transect across Reno that he did a while back.

  13. Tim L says:

    This all is just a little scary…. because.
    Neil Crafter (22:06:51)

    If this is true, then we have COOLED this 4C in all the UHI places, and
    even the sat. temps will be higher as well.
    why be afraid? that is a big difference, crops are in trouble and soforth
    seeds need to be planted in just two weeks, ground is still frozen and
    covered with a new snow fall.
    CO2 where are you?

  14. D. King says:

    Airports are normally oriented to the prevailing winds.
    If this is the case here, the concrete pad would act as
    a heat capacitor. This could be verified by comparing
    the data from this site, to other local, more rural sites.
    The temperature data from this station should drop
    more slowly than others at night.

  15. Tim L says:

    Sun can we please have a little speck? please?

  16. Philip_B says:

    At least they don’t irrigate the grass under the weather station, unlike Australia, where most climate reference sites are also at airports but on patches of nice green grass.

    Or at least they were until recently, when the AGW hysteria made irrigated grass unfashionable. Shutting off the irrigation produced a fall in Australian averaged (measured) temperatures (from the airports).

    And the government has resorted to not updating their temperature graphs to cover up the embarassment of falling temperatures.

    http://www.climatechange.gov.au/impacts/trends/temperature.html

    Note the page from the Department of Climate Change is dated 2009, but stops its temperature trend data in 2005.

    REPLY: Sounds like a job for WUWT. – Anthony

  17. Just Want Truth... says:

    Not possible for heat coming out of the back of jet engines–they don’t produce any heat or nothing. Let’s close up shop and go home. ;)

    YouTube video of thrust from the back of a jet engine and the distance that thrust reaches :

    http://video.google.com/videoplay?docid=-2620422658308473679&ei=OB3PSdvFDIWgqQPA8eTDAQ&q=jet+engine&hl=en&client=firefox-a

  18. Mike McMillan says:

    Never been there, but the parking stands are taxi-in capable (and on concrete). It wouldn’t take more than idle thrust to make the corners, so the temp that far from the aircraft would be maybe 20 C above ambient directly in the exhaust, and probably stay that way long enough to mark a high on a Stevenson thermometer.

    J Campbell (21:20:48) :
    . . . A few degrees can be the difference between a drama or disaster in the case of something like an engine failure.
    Wrong data (presumably data entry) is a leading suspect for EK407 at YMML last week where there was a tailstrike, tracks on the grass and the localizer antenna was cut off 50cm (20″) above the brick localizer building.

    Improper loading is a more likely culprit at YMML. Loaded nose-heavy, when the pilot pulls back on the yoke for a normal rotation, the nose stays on the ground. A couple seconds to recognize the problem and the end of the runway is getting close, so all the way back gets you off the ground, but guarantees a tail strike, and a ton of paperwork.

    Takeoff data at commercial airports is canned for each runway, and the pilots have their own air temp gauges, so there are crosschecks. Lots of leeway built into the system for safety, and you’re pretty far into the no-go area of any takeoff data table before you’re truly unsafe.

    I’d look for an anemometer and temp sensor out by the runway instead of these ones they use for the climate network. Be interesting to see the GHCN highs and lows for Ciampino.

  19. Barry Foster says:

    OT. The Catlin team switched their lights off last night. Hmm, I wonder if that made them more dim?

  20. Hans says:

    Here is the trend up to 2009, it is probably not right because it rises at the end!

    http://www.bom.gov.au/tmp/cc/tmax.aus.0112.18614.png

  21. Just Want Truth... says:

    “Or is it all swamped by Rome’s UHI?”

    Naaah, UHI doesn’t exist. It’s all co2. We have dead polar bears.

  22. JonT says:

    I keep wondering when we see all of these possible heat sources close to weather stations, why doesn’t someone put up a reference station a few hundred yards further from a heat source than an official station. Then it would be a very simple matter to compare the two sets of data and know for sure how much of an effect the heat source was having.

    Of course the effect would not be the same for all heat sources but it might give us an idea of how strong the effect could be.

  23. Ron de Haan says:

    A typical case of Jet Propelled Global Warming.
    Thanks for a job well done.

  24. So where can we find the temp. data recorded at the Ciampino Airport site?

  25. J Campbell says:

    “IImproper loading is a more likely culprit at YMML is a more likely culprit at YMML”

    Usual suspects for takeoff problems are:

    1. Improper loading – Total not CG position
    2.Density altitude with temp being important 5C has given me a tight feeling in the rear
    3. Donk problems

    The rest CG, brakes ice etc are not so common

  26. dearieme says:

    Just to alert you, AW, to a rather snotty allusion to this fine site in a letter to the Telegraph. Scroll down to “Arctic ice thinning”.
    http://www.telegraph.co.uk/comment/letters/5062807/Better-inspections-could-help-to-heal-our-hospitals.html

  27. Dan says:

    The AGW crowd always claims that their measurements and models “allow” for urban heat island effects. Any idea how they actually do that?

  28. fred says:

    Fairly large disturbed area coming into view on Sol at a little past 10:00. Not a spot, it is a light area, maybe some sort of precursor.

  29. pyromancer76 says:

    Is there a global conspiracy to prove abnormally high temperatures for political purposes? Or is pure incompetence at work? Or is there a more innocent reason: most people and institutions did not take temperature seriously enough in the past to be rigorous about gathering data? Perhaps today “conspiracy” is using “innocence” and the “bare beginnings” of the science of temperature data recording and gathering. Looking forward to more posts like this Anthony, and your paper that will help to set the record straight — of course, with the cooperation of real scientists around the world.

    OT, except for the issues of temperature and AGW. Are the ocean experts on WUWT going to post on a Mar. 19 Nature paper by Pollard and DeConto re modeled West Antarctic ice sheets’ coming and going around 1.07 million years ago due to “warm currents and Milankovitch cycles”. According to psyorg.com they use ANDRILL ice core data and, most importantly, the nearest grid point with which to check data. Comments included info that the scientists do not believe that AGW is proven; the abstract was written by a proponent but the research and paper are well done; the CO2 reference is only tagged on at the end so as not to upset the grant givers [and also the editors of Nature]. The CO2 point seems to be that whenever CO2 reached ~400 the ice sheets on the west began(?) melting.

  30. evanmjones says:

    This could be verified by comparing the data from this site, to other local, more rural sites.

    That’s only a start. The rural sites are likely as bad as the US rural sites. Thus, while there may be a difference, there would be less difference measured than the actual difference.

    Same deal when driving. Yes, the temperatures drop as you leave town — but those lower temps are still being measured while passing over a concrete heat sink.

    I suspect the difference in temperature from town to rural is more at certain times of the day, but nonetheless is significant.

    Yes, esp. as Tmax and Tmin are the measuring points. Nothing else “counts”. And that’s when the differences really show.

  31. Ray says:

    UNRELATED:

    Antony, could you put up a quick survey to ask people tow questions;
    1. Did you shut all your lights during Earth Hour?
    2. Did people in your neighbourhood shut their lights of during Earth Hour?

  32. Just Want Truth... says:

    “Dan (04:46:20) :

    The AGW crowd always claims that their measurements and models “allow” for urban heat island effects. Any idea how they actually do that?”

    Well, you see, they say this because they claim they know everything : they know what climate will be 50 to 100 years from now, they say they know manmade co2 is bringing disasters to the earth, they say if we don’t do something now there’s no hope, they say what what they know is beyond debate and anyone who says it isn’t is a denier who is like the people who think the earth is flat, etc, etc.

    Right after they get done saying they know everything they say they need to do more study, because they don’t know everything, so they need more funding.

    So…. does that answer your question? ;)

  33. Just Want Truth... says:

    pyromancer76 (07:14:39) :

    The reasons why this station was placed there is not necessarily the point, although it could be. What is the point is that there are many stations like it, contaminated by heat sources, and they have altered the temperature data.

    Take them out and there is less warming in the data.

  34. ralph ellis says:

    As a commercial pilot, perhaps I could add something. The heat behind a taxiing A320 or 737 is easily detectable at the distances involved. When an aircraft taxis into a stand opposite ours (a similar distance) you can feel the heat, which would equate (I suppose) to 50 – 60 oc. Damp surfaces dry out for a considerable distance behind the aircraft. An aircraft can often sit for 10 mins with the engines running, waiting for ATC clearance.

  35. Just Want Truth... says:

    pyromancer76 (07:14:39) :

    Did you know about this station in Arizona?

    http://wanews.org/news/UHI_files/tucson_from_above.jpg

    I’m still looking for the full story on this one.

  36. ralph ellis says:

    .
    >>The key temperature data is that a few feet above the runway
    >>usually black tar.

    I have often wondered this myself. The data we get is from a cool grassy site, and then we take off on a steaming black tarmac strip that is xx oc warmer.

    Yes, there is a lot of fat in the calculation, but a lot of aircraft are more knackered than the data assumes, and we don’t get an engine failure every day. Now I am not saying that Western aircraft are as knackered as this ‘Vodka Burner’, but some get close. Imagine this dramatic take off with an added engine-failure to boot….

    I have asked for data on the comparison, but the aviation industry does not like aircraft having to shed another 10 passengers. It generally works on the tombstone technology principle.

  37. John Edmondson says:

    Not on this point, but today’s Sunday Telegraph has an article by Christopher Booker about the Work of Dr Mörner
    http://www.telegraph.co.uk/comment/columnists/christopherbooker/5067351/Rise-of-sea-levels-is-the-greatest-lie-ever-told.html

  38. Robert Coté says:

    The warmist crowd has always claimed global warming was man-made. Here’s proof positive.

  39. pyromancer76 says:

    OT about the oceans. I hope people will read a post by Procrustes, “Obama, the South China Sea, and LOST” on the therealbarackobama.wordpress.com.

    Like the — probably global — problem of getting accurate temperature data for actual scientific study, real scientific access to the oceans could be in doubt if the UN becomes the governing body over all the oceans and seas.

  40. Ian M says:

    Two comments.

    I went to the Australian government Department of Climate Change website and found the graphs that go only to 2005. I sent a politely-worded note asking when the graphs will be updated in view of the fact that we are near the end of the third month of 2009.

    And regarding the letter regarding ice thickness, I noted that the writer is at London School of Economics. I have noted that a number of economicsts stick their noses into climate matters, like Lord Stern. Why do they think that they know much about climate? I believe that most or all take IPCC pronouncements as gospel instead of investigating the background for themselves.
    I once sent a polite note regarding climate to an AGW-backing economics prof at our local university and received back a terse message that he did not want to hear from me again. It must be nice to be so sure of oneself!

    Ian

    REPLY: Perhaps you should stop being polite. Greens aren’t known for this, and they seem to get the results the want. – Anthony

  41. John Philip says:

    This is odd, the GCHN and GISS station list has the Ciampino station at co-ordinates 41.78,12.58 [decimal], which is actually on a golf course to the SW of the airport according to Google Earth. But slipups happen, so even assuming the station pictured is the GCHN Ciampino station [No 62316239000] the GHCN only uses data from 1961-1970. GISTEMP shows a negative trend over this short period.

    So it seems the impact of the modern airport development at Ciampino upon the GCHN and GISTEMP networks and hence the estimation of the trend in global mean temp is likely negligible, and in the same context, the photo is of academic interest only.

    REPLY: Certainly that can be one conclusion. But as Steve McIntyre has pointed out, GHCN and GISS seem to have lost track of stations that are still operating today and whose data we can find live posted on the Internet. This may be one of those. I won’t know until I investigate further. That being said, the placement is atrocious, and any researcher using the data from this station would not know of the site problems from the metadata posted on this site unless they did an investigation similar to Paolo’s.

    The problem is that climate researchers generally don’t do this level of investigation, choosing to accept the data on face value. Hansen doesn’t do this, Karl doesn’t do this, and Phil Jones of Hadley is just now coming around to distance himself from the flawed Chinese data, though for the wrong reasons.
    - Anthony

  42. Chris Knight says:

    dearieme (04:23:46) :

    Just to alert you, AW, to a rather snotty allusion to this fine site in a letter to the Telegraph. Scroll down to “Arctic ice thinning”.
    http://www.telegraph.co.uk/comment/letters/5062807/Better-inspections-could-help-to-heal-our-hospitals.html

    Here is the author of said snotty piece:

    Policy and Communications Director
    Bob Ward joined the Grantham Research Institute in November 2008 from Risk Management Solutions, where he was Director of Public Policy. He worked at the Royal Society, the UK national academy of science, for eight years until October 2006, where his responsibilities included leading the media relations team. He has also worked as a freelance science writer and journalist. Bob has a first degree in geology and an unfinished PhD thesis on palaeopiezometry. He is a member of the executive committees of the Association of British Science Writers and the World Conference of Science Journalists 2009, and is a member of the board of the UK’s Science Media Centre.
    Contact details: Room F5.20 New Academic Building
    Tel: 020 7106 1236 Fax: 020 7106 1241

    email: r.e.ward@lse.ac.uk

    Grantham Research Institute of the London School of Economics and Political Science – Chaired by:

    Chair of the Institute
    Professor Lord Nicholas Stern, IG Patel Professor of Economics and Government.
    Professor Stern is the first holder of the IG Patel Chair and also directs the Asia Research Centre and the India Observatory. He was Chief Economist of the World Bank (2000-2003), then Head of the UK Government Economic Service and led a Review of the Economics of Climate Change which was published in October 2006.
    Contact details: email: n.stern@lse.ac.uk (Personal Assistant: k.quirk@lse.ac.uk ). Tel: +44 (0) 20 7955 7871

    Perhaps they would care to receive emails`

    REPLY: Not worth worrying about. – Anthony

  43. Chris Knight says:

    dearieme (04:23:46) :

    Just to alert you, AW, to a rather snotty allusion to this fine site in a letter to the Telegraph. Scroll down to “Arctic ice thinning”.
    http://www.telegraph.co.uk/comment/letters/5062807/Better-inspections-could-help-to-heal-our-hospitals.html

    Here is the author of said snotty piece:

    Policy and Communications Director
    Bob Ward joined the Grantham Research Institute in November 2008 from Risk Management Solutions, where he was Director of Public Policy. He worked at the Royal Society, the UK national academy of science, for eight years until October 2006, where his responsibilities included leading the media relations team. He has also worked as a freelance science writer and journalist. Bob has a first degree in geology and an unfinished PhD thesis on palaeopiezometry. He is a member of the executive committees of the Association of British Science Writers and the World Conference of Science Journalists 2009, and is a member of the board of the UK’s Science Media Centre.
    Contact details: Room F5.20 New Academic Building
    Tel: 020 7106 1236 Fax: 020 7106 1241

    email: r.e.ward@lse.ac.uk

    Bob Ward’s qualifications have a certain “Peter Sellers’ character” ring of quality about them, don’t you think? I am almost certainly misquoting: ” PhD, University of Bombay, Failed.”

    Grantham Research Institute of the London School of Economics and Political Science – Chaired by:

    Chair of the Institute
    Professor Lord Nicholas Stern, IG Patel Professor of Economics and Government.
    Professor Stern is the first holder of the IG Patel Chair and also directs the Asia Research Centre and the India Observatory. He was Chief Economist of the World Bank (2000-2003), then Head of the UK Government Economic Service and led a Review of the Economics of Climate Change which was published in October 2006.
    Contact details: email: n.stern@lse.ac.uk (Personal Assistant: k.quirk@lse.ac.uk ). Tel: +44 (0) 20 7955 7871

    Perhaps they both would care to receive encouraging emails from those who frequent this site.

  44. Mark says:

    Unbelievable.

    What “intellectual” would put a station right behind parked airplanes?

  45. Paolo M. says:

    Thank you Anthony for posting about Roma/Ciampino and more others later.

    Ciampino is a weather station whose daily data are included in the ECA&D dataset and freely available:
    http://eca.knmi.nl./

    No doubt that the station above is Roma/Ciampino whose WMO codex is 16139.
    The GHCN co-ordinates must be wrong.
    Moreover, ECA&D has daily data till 2005 and I have got data till yesterday.
    You can find real time daily data at the site of the Italian Air Force Met. Service.
    For example, right now, at 20:00 UTC you can read Roma/Ciampino temperature extremes taken yesterday at this link:
    http://www.meteoam.it/modules/tempoInAtto/infoStazione.php?icao=LIRA

    Tmin was 8.4° at 01:50 and Tmax was 18.8° at 14:20.
    These data are published every day at 09:00 UTC.

    That page reports also today’s daytime high (published at 18:00) and nighttime low (at 06:00), that are different with respct to daily extremes.
    Today’s low was 13.4°; the high was 20.0°, thanks to scirocco weather.

    Before taking any climate information out from a weather station, there is no other way (at least a seriuos way) that doing that kind of work that Anthony started for the US.

    Of great importance, of course, it would be also to know the station history.
    Ciampino, for example, had for sure a lot of air traffic increment when was opened to civil air traffic and wide plane parking lot had to have been added.
    Survey like this allows to discriminate bad or dubious stations from better ones.

  46. Paolo M. says:

    I’m quite sure that when the station was put there, it was under WMO requirements.
    Then times go and today you add a truck parking lot, tomorrow a taxiway and the day after a plane parking area and so on.
    When a whole air field is compromised, often also by city espansion, I think nothing remains to do.

  47. James P says:

    It doesn’t affect the main thrust of this article (pun intended) but I note that the truck being blown into the water by jet exhaust appears to lack an engine! Without that modification, it might have stayed on the ground…

  48. Jeff Alberts says:

    2.Density altitude with temp being important 5C has given me a tight feeling in the rear

    I’d be sure to see a doctor about that if I were you.

  49. That is a “Club of Rome” station!!
    “Che bella cosa e na giornatta di sole!”

  50. Keith Minto says:

    If you look at the link provided by Philip_B and at the Colour map of Australia,it seems that any warming trend in South Eastern Australia is either +0.5c or -0.5c over 100years, just where most of Australia’s population lives and where most of the sensors are. The ‘hot-spot’ in the centre may have been picked by one sensor!
    This tiny SE change surely must be within measurement error.

  51. Mike McMillan says:

    J Campbell (04:17:08) :
    Usual suspects for takeoff problems are:
    1. Improper loading – Total not CG position
    2.Density altitude with temp being important 5C has given me a tight feeling in the rear
    3. Donk problems

    Disagreeable me, sorry.

    1. CG (center of gravity) position is definitely a problem. All freight containers are weighed and known, but containers may still be loaded aboard in an incorrect order, and as I said, that makes the aircraft handle in unexpected ways, resulting in over-rotation and tailstrikes. An overweight takeoff will require more rotation, but at a normal rate and that shouldn’t get a tailstrike.

    2. Airlines have temperature/pressure/gross weight takeoff charts computed for every runway they use at an airport; it’s all part of their certification for operations at an airport. Aside from the go/no-go aspect, pilots use the charts for reduced power takeoffs whenever they can, which is easier on the engines. Throttles are set for the highest temperature on a runway chart that allows safe takeoff, which produces more power than you actually need but less power than you actually have available. This leaves a good reserve of power in case of difficulty. The actual density altitude doesn’t enter in for reduced power, and for full power takeoffs, the pilots use their own ambient temperature gauge.

    3. Not a clue what a donk is.
    .

    ralph ellis (07:58:08) :
    The heat behind a taxiing A320 or 737 is easily detectable at the distances involved. When an aircraft taxis into a stand opposite ours (a similar distance) you can feel the heat, which would equate (I suppose) to 50 – 60 oc.

    That would be a bit over my 20 C above ambient estimate, assuming you mean actual temp and not 50 C above ambient. I don’t have my charts handy, but really hot temps as far aft as the Ciampino Stevenson screens are, would take higher power and damaging wind speeds.
    .

    I guess I’ll hit the ‘Submit’ button, then check for typos.

  52. Michael Whelan says:

    Aircraft aside, what is the effect on the weather station of a 30,000 square metre x 4 metre thick slab of concrete on one side and a 50,000 square metre carpark on the other?

  53. John Marshall says:

    Good film clip. Yes it is true as I have seen it happen, with someone driving the vehicle as well. A good reason to use satellites to measure global surface temperatures.

  54. Pamela Gray says:

    My boyfriend was topside on the USS Constellation during Vietnam. A jet took off and blew debri someone had left on the deck into the side of his head, knocked him out, and broke his jaw. No cuts, just a bruise, and he didn’t know his jaw was broken (or his head banged around) till he got back from a night’s leave looking very sick. He ended up in the ship’s infirmary for 90 days. Afterwards he had developed left over traumatic brain injury changes in his thinking and emotional state, eventually leading to his decision to leave the military just short of 6 years. That truck is visible. A small wrench or rock can kill you just as surely. Now you know why swabbing the deck is probably one of the most important jobs on a carrier.

  55. leebert says:

    Oh no! This revelation might cause Italy to form a new government!

  56. Could Paolo have meant WHO ID # 16239, not 16139? I find the former, but not the latter, in the WMO flatfile, NCDC station locate, and ECA&D list.

  57. Mike McMillan says:

    Michael Whelan (23:13:29) :

    The Hugo-winning artist ?

    Aircraft aside, what is the effect on the weather station of a 30,000 square metre x 4 metre thick slab of concrete on one side and a 50,000 square metre carpark on the other?

    Concrete on the ramps and taxiways generally runs 2-3 ft ( <1 meter) thick on a base of crushed rock. I have heard of 4 meter thickness in the touchdown zones of some runways. Gonna be warming, though, holding heat into the night.

  58. Mike M says:

    J Campbell (21:20:48) Not ‘wrong’ temperature data – cold temperature data. In general an incorrect reading saying that it is warmer than it actually is will not cause any problem in aviation excepting perhaps icing or something associated to freezing. Example, if you think its 10 degrees warmer than it really is then your TO distance will be shorter than you thought it would be, your load capacity will be greater, your engine performance better, etc.

  59. Paolo M. says:

    No oil for pacifists:
    sorry, I ment 16239.
    WMO codex for Italy start from 160xx from the far North to 16490 for the southern island of Lampedusa. Sardinia has 165xx.

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