GISS & METAR – dial "M" for missing minus signs: it's worse than we thought

Here’s a story about how one missing letter, an M, can wreck a whole month’s worth of climate data. It is one of the longest posts ever made on WUWT, I spent almost my entire Saturday on it. I think it might also be one of the most important because it demonstrates a serious weakness in surface data reporting.

In my last post, we talked about the  a curious temperature anomaly that Jean S. found in the March GISS data and posted at Climate Audit:

http://climateaudit.files.wordpress.com/2010/04/ghcn_giss_hr2sst_250km_anom03_2010_2010_1971_2000.gif?w=520&h=307

The anomaly over Finland has an interesting signature to it, and the correction that GISS posted on their website confirms something I’ve been looking at for a few months.

The data shown between 4/13 and 4/15 were based on data downloaded on 4/12 and included some station reports from Finland in which the minus sign may have been dropped.

With some work I started back in late December and through January, and with GISS putting stamp of approval on “missing minus signs” I can now demonstrate that missing minus signs aren’t just an odd event, they happen with regularity, and the effect is quite pronounced when it does happen. This goes to the very heart of data gathering integrity and is rooted in simple human error. The fault lies not with GISS (though now they need a new quality control feature) but mostly with NOAA/NCDC who manages the GHCN and who also needs better quality control. The error originates at the airport, likely with a guy sitting in the control tower. Readers who are pilots will understand this when they see what I’m talking about.

I’ve seen this error happen all over the world. Please read on and be patient, there is a lot of minutiae that must be discussed to properly frame the issue. I have to start at the very bottom of the climate data food-chain and work upwards.

First, a discussion about the root of error and the differences between the surface and satellite dataset. I should mention that in the satellite image from NASA’s Earth Observations (NEO), we don’t see the same error as we see in the GISTEMP map above.

NASA NEO March 1-31 2010 day satellite measured temp anomaly – click for larger image

Why? Better sensors, maybe, but mostly it has to do with a different data gathering methodology. In the surface data sets, including land and ocean data, most every datapoint is touched by a human hand, even airport data that gets done by automated airport sensors sometimes gets transcribed manually (often in third world and technologically stunted countries). In the surface data, thousands of sensors are spread across the globe, many different designs, many different exposures, many different people with different standards of measurement and reporting. The precision, accuracy, and calibration of the vast surface network varies, especially when we have broad mix of instrumentation types.For example in the US Historical Climatological Network the equipment varies significantly.

In satellite data, the data is measured at a single point with one sensor type, the Microwave Sounder Unit on the satellite, calibrated to a precision source on-board. On-board redundant precision platinum resistance thermometers (PRTs) carried on the satellite radiometers. The PRT’s are individually calibrated in a laboratory before being installed in the instruments. The satellite data is automatically measured and  transmitted. In contrast to the surface temperature record, no human hands touch the data gathering or data reporting process. Satellite data generation is far more homogeneous than the mish-mash of surface data.

I think it would be safe to say that the chances of human error in raw surface data are at least an order of magnitude greater (if not several) than error in raw satellite data. Post measurement processing is another issue, but for the purposes of this essay, I’m focusing only on raw data gathering and transmittal.

As mentioned in the recently updated compendium of issues with the surface temperature data by Joe D’Aleo and myself, there has been a move in the Global Historical Climatological Network (GHCN) to rely more and more on airports for climate data. This, in my opinion, is a huge mistake because in addition to those issues

E.M. Smith aka “Chiefio” reports that in GISS (which uses GHCN) worldwide, there has been a wholesale migration towards airport weather data as a climatic data source.  In an email sent to me on Jan 20, 2010 he says that

Look at:

http://chiefio.wordpress.com/2009/08/26/agw-gistemp-measure-jet-age-airport-growth/

which as a fairly good descriptions of the problems in the data, we have a global report for GHCN as of that August data.  There is more deail in the link, but I think you care about “now”:

Percentage of sites that are AIRPORTS NOW, by decade of record

Year   S.P   S.C   S.T   S.W   EQ.   N.W   N.T   N.C   N.P  Total

1909   0.0  42.0  15.1  28.2  29.2  36.7  22.8  33.3  44.4  25.4

1919   0.0  36.4  12.8  23.5  25.1  37.7  20.9  35.0  39.8  24.1

1929   0.0  37.0  11.9  27.4  27.7  32.7  20.4  35.9  56.4  24.1

1939   0.0  43.9  17.6  32.0  33.8  29.1  20.2  36.2  51.0  25.1

1949   0.0  32.3  24.4  37.6  44.4  31.8  23.3  39.3  60.9  29.1

1959   0.0  24.0  35.0  50.0  59.4  39.4  30.9  41.0  62.9  37.3

1969   0.0  18.1  39.3  53.2  63.2  40.2  31.4  41.1  61.5  39.0

1979   0.0  17.9  39.1  52.0  64.2  40.7  28.8  41.1  62.3  37.7

1989   0.0  20.7  41.5  52.5  67.8  41.9  29.1  40.8  64.9  37.7

1999   0.0  21.0  53.5  57.4  68.0  53.0  32.6  49.0  59.0  41.6

2009   0.0  17.9  74.0  64.7  66.5  51.5  30.2  45.4  57.3  41.0
This is by major climate latitude band, the total is 41% for the globe (and rising daily 😉
Also in:

I do break outs by continent and by some countries.  For the USA, I further do a specific with / without USHCN (the older version, not the USHCN.v2 put in 15Nov09) and findFor COUNTRY CODE: 425

But it masks the rather astounding effect of deletions in GHCN without the USHCN set added in:
LATpct: 2006  3.7 18.3 29.5 33.2 14.4  0.0  0.4  0.3  0.1  0.1 100.0

AIRpct:       1.3  4.0  6.3  6.7  3.2  0.0  0.4  0.3  0.1  0.1 22.4

LATpct: 2007  8.2 17.2 28.4 26.9 11.2  0.0  3.7  3.0  0.7  0.7 100.0

AIRpct:       8.2 15.7 27.6 23.1  9.0  0.0  3.7  3.0  0.7  0.7 91.8

LATpct: 2008  8.8 16.9 28.7 26.5 11.0  0.0  3.7  2.9  0.7  0.7 100.0

AIRpct:       8.8 15.4 27.9 22.8  8.8  0.0  3.7  2.9  0.7  0.7 91.9

LATpct: 2009  8.1 17.8 28.1 26.7 11.1  0.0  3.7  3.0  0.7  0.7 100.0

AIRpct:       8.1 16.3 27.4 23.0  8.9  0.0  3.7  3.0  0.7  0.7 91.9

DLaPct: 2009  4.3 18.4 29.5 32.5 13.6  0.0  0.7  0.9  0.2  0.1 100.0

DArPct:       2.1  5.7  8.8  8.9  3.7  0.0  0.6  0.8  0.2  0.1 30.7

That in the YEAR 2009 the USA has almost 92% airports in GHCN.

So clearly, airports make up a significant portion of the climate data.

On the issues of airports as climate station, obvious issues with siting, UHI, failing ASOS instrumentation, and conflicting missions (aviation safety -vs-climate) aside, I’m going to focus on one other thing unique to airports: METAR

What is METAR you ask? Well in my opinion, a government invented mess.

When I was a private pilot (which I had to give up due to worsening hearing loss – tower controllers talk like auctioneers on the radio and one day I got the active runway backwards and found myself head-on to traffic. I decided then I was a danger to myself and others.) I learned to read SA reports from airports all over the country. SA reports were manually coded teletype reports sent hourly worldwide so that pilots could know what the weather was in airport destinations. They were also used by the NWS to plot synoptic weather maps. Some readers may remember Alden Weatherfax maps hung up at FAA Flight service stations which were filled with hundreds of plotted airport station SA (surface aviation) reports.

The SA reports were easy to visually decode right off the teletype printout:

From page 115 of the book "Weather" By Paul E. Lehr, R. Will Burnett, Herbert S. Zim, Harry McNaught - click for source image

Note that in the example above, temperature and dewpoint are clearly delineated by slashes. Also, when a minus temperature occurs, such as -10 degrees Fahrenheit, it was reported as “-10”. Hang on to that, it is important.

The SA method originated with airmen and teletype machines in the 1920’s and lasted well into the 1990’s. But like anything these days, government stepped in and decided it could do it better. You can thank the United Nations, the French, and the World Meteorological Organization (WMO) for this one. SA reports were replaced by METAR in 1996.

From Wikipedia’s section on METAR

METAR reports typically come from airports or permanent weather observation stations. Reports are typically generated once an hour; if conditions change significantly, however, they can be updated in special reports called SPECIs. Some reports are encoded by automated airport weather stations located at airports, military bases, and other sites. Some locations still use augmented observations, which are recorded by digital sensors, encoded via software, and then reviewed by certified weather observers or forecasters prior to being transmitted. Observations may also be taken by trained observers or forecasters who manually observe and encode their observations prior to transmission.

History

The METAR format was introduced 1 January 1968 internationally and has been modified a number of times since. North American countries continued to use a Surface Aviation Observation (SAO) for current weather conditions until 1 June 1996, when this report was replaced with an approved variant of the METAR agreed upon in a 1989 Geneva agreement. The World Meteorological Organization‘s (WMO) publication No. 782 “Aerodrome Reports and Forecasts” contains the base METAR code as adopted by the WMO member countries.[1]

Naming

The name METAR is commonly believed to have its origins in the French phrase message d’observation météorologique pour l’aviation régulière (“Aviation routine weather observation message” or “report”) and would therefore be a contraction of MÉTéorologique Aviation Régulière. The United States Federal Aviation Administration (FAA) lays down the definition in its publication the Aeronautical Information Manual as aviation routine weather report[2] while the international authority for the code form, the WMO, holds the definition to be aerodrome routine meteorological report. The National Oceanic and Atmospheric Administration (part of the United States Department of Commerce) and the United Kingdom‘s Met Office both employ the definition used by the FAA. METAR is also known as Meteorological Terminal Aviation Routine Weather Report or Meteorological Aviation Report.

I’ve always thought METAR coding was a step backwards, for reasons I’ll discuss shortly.

But first, quick! Spot the temperature and dewpoint in this METAR report:

The following is an example METAR from Burgas Airport in Burgas, Bulgaria, and was taken on 4 February 2005 at 16:00 Coordinated Universal Time (UTC).

METAR LBBG 041600Z 12003MPS 310V290 1400 R04/P1500N R22/P1500U +SN BKN022 OVC050 M04/M07 Q1020 NOSIG 9949//91=

Could you read this and know what the weather is in Burgas? I can, only becuase I’ve looked at hundreds the past few months, but I still have to pick through the report to find it. The reason is that METAR is a variable field reporting format. Data isn’t always in the same position.

In the report above. The temperature and dewpoint is: M04/M07

M04/M07 indicates the temperature is −4 °C (25 °F) and the dewpoint is −7 °C (19 °F). An M in front of the number indicates that the temperature/dew point is below zero (0) Celsius.

Notice also that the entire METAR report is visually more complex. This is fine if you are having computers code it, but many METAR reports are still hand coded by technicians at airports, and thus begins the introduction of human error into the climate data process. Complexity is not a good thing when manual labor is involved as it increases the likelihood of error.

Here is where METAR coding departs from normal numeric convention. SA reports did not have this problem.

In the METAR report above, instead of using the normal way we treat and write negative numbers, some policy wonk decided that we’ll use the letter “M” to report a negative number. Only a bureaucrat could think like this.

So instead of a below zero Centigrade temperature and dewpoint looking like this:

-04/-07

in the “new and improved” METAR coding, it looks like this:

M04/M07

OK not a problem you say? Well I beg to differ, because it forces technicians who manually code METAR reports for transmission to do something they would not do anywhere else, and that’s write down an “M” instead of a minus sign. Using an M is totally counter-intuitive and against basic math training, and increases the likelihood of error.

It gets worse. Let’s say the technician makes a boo-boo and puts a minus sign instead of an “M” in front of the numbers for temperature/dewpoint. You’d think this would be alright, and the system would correctly interpret it, right?

Let’s put the METAR report from Burgas Airport into an online METAR decoder.

http://www.wx-now.com/Weather/MetarDecode.aspx

Here’s the report with the easy to make mistake, using minus sign instead of M for the temperature.

METAR LBBG 041600Z 12003MPS 310V290 1400 R04/P1500N R22/P1500U +SN BKN022 OVC050 -04/M07 Q1020 NOSIG 9949//91=

The output from the online METAR decoder reads:

Hey look at that, the temperature is 39°F (3.8°C). Minus signs are discarded from METAR decoding. Note that decoded METAR temperature also comes out the same if the “M” is missing in front of the 04/-07 or 04/M07

If it had been decoded correctly we would have gotten:

(-4) degrees Celsius = 24.8 degrees Fahrenheit

A whole 14.2 degrees F difference!

Reference for METAR decoding:

http://www.met.tamu.edu/class/METAR/quick-metar.html

Also note that METAR data has no year stamp component to the data, so the METAR decoder has no way of knowing this was a report from 2005, not 2010. Since each METAR report is essentially disposable within 24 hours, this presents no problem for pilots, they don’t care. But if you are tracking climate over years using METAR data, not having a year time stamp increases the likelihood of error.

Also the temperature error itself in this case has no bearing on a pilot’s decision to takeoff or land. Unless they are worried about density altitude on hot humid days, the temperature is a throwaway datum. They are mostly concerned about winds, sky conditions, and barometer (altimeter setting). In fact cool/cold days are far better for aviators; see AOPA’s Why Airplanes Like Cool Days Better.

My point here is this:

If a pilot or tower controller sees an erroneous METAR report like this:

METAR LBBG 041600Z 12003MPS 310V290 1400 R04/P1500N R22/P1500U +SN BKN022 OVC050 -04/M07 Q1020 NOSIG 9949//91=

Or this:

METAR LBBG 041600Z 12003MPS 310V290 1400 R04/P1500N R22/P1500U +SN BKN022 OVC050 04/M07 Q1020 NOSIG 9949//91=

Pilots/controllers/dispatchers aren’t likely to care, since current temperature and dewpoint are not important to them at these cooler temperatures. They also aren’t likely to call up the tower and holler at the technician to say “Hey, the temperature is wrong!”. Further, since the METAR report may be reissued sometime within the hour if somebody DOES spot the error, problem solved.

Point is that updates/corrections to METAR data may not be logged for climate purposes, since they are likely to be seen as duplicate reports because of the hourly timestamp.

So, in the case of M’s and minus signs, the propensity exists for erroneous METAR reports to not get corrected and to stay logged in the system, eventually finding their way into the climate database if that airport happens to be part of GISS, CRU, or GHCN datasets.

Maddeningly, even when egregious errors in aviation weather data are pointed out and even acknowledged by the reporting agency,  NOAA keep them in the climate record as was demonstrated last year in Honolulu, HI International Airport when a string of new high temperature records were set by a faulty ASOS reporting station. NOAA declined to fix the issue in the records:

NOAA: FUBAR high temp/climate records from faulty sensor to remain in place at Honolulu

The key sentence from that story from KITV-TV:

The National Weather Service said that is not significant enough to throw out the data and recent records.

Hmmm, look at another nearby station and compare the differences. You be the judge.

Does NOAA consider this a climate reporting station? Yes according to NCDC MMS database, it is part of the “A” network, designated for climate:

Clearly, NOAA simply doesn’t seem to care that erroneous records finds their way into the climatic database.

OK back to the METAR issue.

The problem with METAR reporting errors is worldwide. I’ve found many examples easily in my spare time. Let’s take for example, a station in Mirnvy, Russia. It is in Siberia at 62.5° N 113.9° E and has an airport, is part of GHCN, and reports in METAR format.

Weather Underground logs and plots METAR reports worldwide, and these METAR reports are from their database on November 11th, 2009.

It shows a clear error in the 12:30PM (330Z) and 1 PM (400Z) METAR report for that day:

http://www.wunderground.com/history/airport/UERR/2009/11/1/DailyHistory.html?req_city=NA&req_state=NA&req_statename=NA

UERR 010330Z    22005G08MPS 9999 -SN 21/M23 Q1026 NOSIG RMK QFE738 24450245

UERR 010400Z    22005G08MPS 9999 -SN SCT100 OVC200 20/M22 Q1025 NOSIG RMK QFE737 24450245

UERR 010430Z    21005G08MPS 4000 -SN SCT100 OVC200 M20/M22 Q1024 NOSIG RMK QFE737 24450245

UERR 010430Z    21005G08MPS 4000 -SN SCT100 OVC200 M20/M22 Q1024 NOSIG RMK QFE737 24450245

UERR 010500Z    21005G08MPS 4000 -SN SCT100 OVC200 20/M22 Q1023 NOSIG RMK QFE736 24450245

Note the missing ” M” on the 12:30PM (330Z) and 1 PM (400Z). It happens again at 2PM (500Z). Of course it isn’t very noticeable looking at the METAR reports, but like the GISS plot of Finland, stands out like a sore thumb when plotted visually thanks to Weather Underground:

Mirnvy, Russia

The effect of the missing “M” is plotted above, which coincidentally looks like an “M”.

Put those METAR reports in this online METAR decoder: http://www.wx-now.com/Weather/MetarDecode.aspx and you get 70F for 12:30PM and 68F for 1PM

What do you think 70 degree F spike this will do to monthly averaged climate data in a place where the temperature stays mostly below freezing the entire month?

http://www.wunderground.com/history/airport/UERR/2009/11/1/MonthlyHistory.html?MR=1

Does NOAA log METAR data from Mirnvy Russia (ICAO code UERR)?

Yes, they do. Plus many other METAR reporting stations discussed here.

Does NCDC classify it as a climate station?

Yep, it is part of the “A” network. Which means it either directly reports climate data and/or is used to adjust data at other stations, such as GHCN stations.

List of GHCN stations:

http://www1.ncdc.noaa.gov/pub/data/ghcn/daily/ghcnd-stations.txt

It is not however, part of GHCN. But there are plenty stations that have this error that are part of GHCN. Yakutsk, Russia, also in Siberia is part of GHCN and has a METAR reporting error. Here’s an example what one off-coded hourly reading will do to the climate database.

The city of Yakutsk, one of the coldest cities on earth, reported a high of 79˚F on November 14th with a low of -23˚F.

Weather Underground seems to have done some quality control to the METAR reports, but the erroneous high temp remains in the daily  and monthly report:

http://www.wunderground.com/history/station/24959/2009/11/14/DailyHistory.html

http://www.wunderground.com/history/station/24959/2009/11/14/MonthlyHistory.html

A month later, it happened again reporting a high of 93˚F on December 14th with a low of -34˚F

And the erroneous 93F high temp remains in both the daily and monthly reports, but has been removed from the METAR report, so I can’t show you the missing “M” I observed back in January. I wish I had made a page screen cap.

http://www.wunderground.com/history/station/24959/2009/12/14/DailyHistory.html

http://www.wunderground.com/history/station/24959/2009/12/14/MonthlyHistory.html

When the temperature data was calculated with that error then, this was found:

The average for the day,  30˚F, was some 67˚F above normal, pushing the anomaly for the month of December from 3.6˚F above normal to 5.9˚F above normal… quite a shift!

More examples:

Here’s an example of a properly coded METAR report from Nizhnevartovsk, Russia,  for December 11, 2009, but the data is wrong. I’m thinking it was supposed to be M30 but came out M13. The dewpoint value M16 is also erroneous.

Nizhnevartovsk, Russia Dec 7, 2009

METAR USNN 111230Z 00000MPS P6000 SCT026 OVC066 M27/M29 Q1014 NOSIG RMK QFE755 SC062

METAR USNN 111300Z 12005G08MPS P6000 SCT066 OVC200 M13/M16 Q1035 NOSIG RMK QFE772 SC063

METAR USNN 111330Z 12005G08MPS P6000 SCT066 OVC200 M13/M16 Q1035 NOSIG RMK QFE772 SC063

METAR USNN 111400Z 00000MPS P6000 SCT020 OVC066 M28/M29 Q1014 NOSIG RMK QFE755 SC065

And it was not a one time occurrence, happening again on Dec 25th as shown in the Monthly graph:

Nizhnevartovsk, Russia, December 2009

http://www.wunderground.com/history/airport/USNN/2009/12/25/MonthlyHistory.html

The daily graph and METAR reports, notice it happened about the same time (1300Z) and in the same way (M27 then M13) , perhaps pointing to the same technician on duty making the same habitual mistake again. Maybe too much Vodka having to work the Xmas night shift?

Nizhnevartovsk, Russia Dec 25, 2009

METAR USNN 251230Z 11006MPS 2200 -SN SCT014 OVC066 M27/M30 Q1015 NOSIG RMK QFE757 SC055

METAR USNN 251300Z 35002MPS 6000 -SN SCT015 OVC066 M13/M15 Q1010 NOSIG RMK QFE752 SC03

METAR USNN 251330Z 12006MPS 4100 -SN SCT015 OVC066 M27/M29 Q1014 NOSIG RMK QFE756 SC055

http://www.wunderground.com/history/airport/USNN/2009/12/25/DailyHistory.html

It did not appear initially to be in the GHCN list or on the GISS list, but I’ve found that some of the names on Weather Underground are different from the place names in the GHCN and GISS lists. It turns out that if you search in Weather Underground for the station ALEKSANDROVSKOE it will point you to use the data from Nizhnevartovsk. ALEKSANDROVSKOE is a GHCN/GISS station.

I found other instance of METAR errors for that station, this one was quite pronounced on Jan 16th, 2009, lasting for 7 hours before it was corrected.

Nizhnevartovsk, Russia Jan 16, 2009

Here’s the METAR reports

METAR USNN 151800Z 23002MPS P6000 BKN066 OVC200 M22/M24 Q1009 NOSIG RMK QFE751 SC038

METAR USNN 151830Z 23002MPS 2900 -SHSN SCT020CB OVC066 22/M23 Q1009 NOSIG RMK QFE751 SC038

METAR USNN 151900Z 23002MPS 2100 -SHSN SCT019CB OVC066 21/M23 Q1009 NOSIG RMK QFE751 SC038

METAR USNN 152000Z 24001MPS 5000 -SHSN SCT022CB OVC066 21/M22 Q1009 NOSIG RMK QFE751 SC038

METAR USNN 152030Z 24002MPS 4300 -SHSN SCT020CB OVC066 21/M22 Q1009 NOSIG RMK QFE751 SC038

METAR USNN 152100Z 24002MPS 6000 -SHSN SCT018CB OVC066 20/M22 Q1009 NOSIG RMK QFE751 SC038

METAR USNN 152130Z 25002MPS P6000 SCT020CB OVC066 20/M22 Q1009 NOSIG RMK QFE751 SC038

METAR USNN 152200Z 28002MPS P6000 SCT022CB OVC066 20/M22 Q1009 NOSIG RMK QFE752 SC038

METAR USNN 152300Z 27003MPS P6000 -SHSN SCT016CB OVC066 M19/M21 Q1010 NOSIG RMK QFE752 SC038

http://www.wunderground.com/history/airport/USNN/2009/1/16/DailyHistory.html

The monthly report shows the event:

Nizhnevartovsk, Russia, January 2009

http://www.wunderground.com/history/airport/USNN/2009/1/16/MonthlyHistory.html

It happened twice on Feb 2nd, 2007, and with a space added between the M and 09 on the 0300Z report, it is a clear case of human error:

METAR USNN 020100Z 11010G15MPS 0500 R03/1200 +SN +BLSN VV002 M09/M11 Q1003 TEMPO 0400 +SN +BLSN VV002 RMK QFE748 QWW060 MOD ICE MOD TURB S

METAR USNN 020200Z 12009G14MPS 0500 R03/1200 +SN +BLSN VV002 M09/M10 Q1001 TEMPO 0400 +SN +BLSN VV002 RMK QFE747 QWW060 MOD ICE MOD TURB S

METAR USNN 020300Z 11008G13MPS 1100 R03/1200 SN +BLSN BKN004 OVC066 M 09/M10 Q1000 NOSIG RMK QFE745 QRD120 MOD ICE MOD TURB SC045

...

METAR USNN 021200Z 18009MPS P6000 -SHSN DRSN SCT017CB OVC066 M07/M09 Q0989 TEMPO 2000 SHSN RMK QFE736 MOD ICE MOD TURB SC042

METAR USNN 021300Z 16009MPS P6000 DRSN SCT016CB OVC066 08/M11 Q0989 NOSIG RMK QFE736 MOD ICE MOD TURB SC042

METAR USNN 021400Z 16008MPS P6000 DRSN SCT016CB OVC066 M08/M11 Q0989 NOSIG RMK QFE736 MOD ICE MOD TURB SC042

http://www.wunderground.com/history/airport/USNN/2007/2/2/DailyHistory.html

The monthly data shows the double peak:

http://www.wunderground.com/history/airport/USNN/2007/2/2/MonthlyHistory.html

I’m sure many more can be found, I invite readers to have a look for themselves by looking for such events at Weather Underground

It is not just Russia that has METAR reporting errors

Lest you think this a fault of Russia exclusively, it also happens in other northern hemisphere Arctic site and also in Antarctica.

Svalbard, Oct 2, 2008

METAR ENSB 020550Z 13012KT 6000 -SN FEW010 SCT015 BKN030 M04/M06 Q1013 TEMPO 4000 SN BKN012

METAR ENSB 020650Z 14013KT 9000 -SN FEW010 SCT018 BKN040 03/M06 Q1013 TEMPO 4000 SN BKN012

METAR ENSB 020750Z 15011KT 9999 -SN FEW015 SCT025 BKN040 M03/M07 Q1013 TEMPO 4000 SN BKN012

http://www.wunderground.com/history/airport/ENSB/2008/10/2/DailyHistory.html

Eureka, Northwest Territory, Canada March 3 2007

It hit 109.4 F (43C) there on March 3rd 2007 according to this METAR report. Eureka is the northernmost GHCN station remaining for Canada. It’s temperature gets interpolated into adjacent grid cells.

CWEU 031600Z 14004KT 15SM FEW065 BKN120 M43/M45 A2999 RMK ST1AS2 VIA YQD SLP150

CWEU 031700Z 15005KT 10SM FEW065 BKN012 43/46 A3000 RMK SF1AS1 VIA YQD SLP163

Decoded: 11:00 AM 109.4 °F 114.8 °F 100% 30.01 in 10.0 miles SSE 5.8 mph - Mostly Cloudy

CWEU 031800Z 11003KT 15SM FEW050 FEW065 OVC130 M43/M46 A3001 RMK SF2SC1AS1 VIA YQD SLP164

http://www.wunderground.com/history/airport/CWEU/2007/3/3/DailyHistory.html

In these cases below for Antarctic stations Dome C and Nico, the METAR reports seem to have all sorts of format issues and I’m not even sure how where the error occurs, except that Weather Underground reports a spike just like we see in Russia.

Dome C station Dec 9, 2009

AAXX 0900/ 89828 46/// ///// 11255 36514 4//// 5//// 90010

AAXX 0901/ 89828 46/// ///// 10091 36514 4//// 5////

AAXX 09014 89828 46/// /1604 11225 36480 4//// 5//// 9014

http://www.wunderground.com/history/station/89828/2009/12/9/DailyHistory.html

Nico Station,  University of Wisconsin Dec 9, 2009

AAXX 0920/ 89799 46/// ///// 11261 4//// 5//// 92030

AAXX 0920/ 89799 46/// ///// 11103 4//// 5//// 92040

AAXX 0921/ 89799 46/// ///// 11270 4//// 5////

http://www.wunderground.com/history/station/89799/2009/12/9/DailyHistory.html

Admusen Scott Station Jan 14th, 2003

Here’s generally properly formatted METAR data, but note where the technician coded the extra space, oops!

NZSP 131350Z GRID36007KT 9999 IC SCT020 BKN060 M31/ A2918 RMK SDG/HDG

NZSP 131450Z GRID36007KT 9999 IC FEW010 FEW020 SCT035 SCT050 M3 1/ A2918 RM K SDG/HDG

NZSP 131550Z GRID10008KT 9999 IC BCFG FEW010 SCT020 BKN050 M31/ A2919 RMK VIS E 2400 BCFG E SDG/HDG

http://www.wunderground.com/history/station/89009/2003/1/14/DailyHistory.html

And I’m sure there are many more METAR coding errors yet to be discovered. What you see above is just a sampling of a few likely candidates I looked at over a couple of hours.

Missing M’s – Instant Polar Amplification?

It has been said that the global warming signature will show up at the poles first. Polar Amplification is defined as:

“Polar amplification (greater temperature increases in the Arctic compared to the earth as a whole) is a result of the collective effect of these feedbacks and other processes.It does not apply to the Antarctic, because the Southern Ocean acts as a heat sink. It is common to see it stated that “Climate models generally predict amplified warming in polar regions”, e.g. Doran et al. However, climate models predict amplified warming for the Arctic but only modest warming for Antarctica.

Interestingly, the METAR coding error has its greatest magnitude at the poles, becuase the differences in the missing minus sign become larger as the temperature grows colder. Eureka, NWT is a great example, going from -43°C to +43°C (-45.4°F to 109.4°F) with one missing “M”.

You wouldn’t notice METAR coding errors at the equator, because the temperature never gets below 0°C. Nobody would have to code it. In middle latitudes, you might see it happen, but it is much more seasonal and the difference is not that great.

For example:

M05/M08  to 05/M08 brings the temp from -5°C to +5°C, but in a place like Boston, Chicago, Denver, etc a plus 5C temperature could easily happen in any winter month a -5C temperature occurred. So the error slips into the noise of “weather”, likely never to be noticed. But it does bump up the temperature average a little bit for the month if uncorrected.

But in the Arctic and Antarctic, a missing M on a M20/M25 METAR report makes a 40°C difference when it becomes +20°C. And it doesn’t seem likely that we’d see a winter month in Siberia or Antarctica that would normally hit 20°C, so it does not get lost in the “weather” noise, but becomes a strong signal if uncorrected.

Confirmation bias, expecting to see polar amplification may be one reason why until now, nobody seems to have pointed it out. Plus, the organizations that present surface derived climate data, GISS, CRU, only seem to deal in monthly and yearly averages. Daily or hourly data is not presented that I am aware of, and so if errors occur at those time scales, they would not be noticed. Obviously GISS didn’t notice the recent Finland error, even though it was glaringly obvious once plotted.

With NASA GISS admitting that missing minus signs contributed to the hot anomaly over Finland in March, and with the many METAR coding error events I’ve demonstrated on opposite sides of the globe, it seems reasonable to conclude that our METAR data from cold places might very well be systemically corrupted with instances of coding errors.

The data shown between 4/13 and 4/15 were based on data downloaded on 4/12 and included some station reports from Finland in which the minus sign may have been dropped.

4/15/10 http://data.giss.nasa.gov/gistemp/

That darned missing M, or an extra space, or even writing “-” when you mean “M” (which is counterintuituve to basic math) all seem to have a factor in the human error contributing to data errors in our global surface temperature database. To determine just how much of a problem this is, a comprehensive bottom up review of all the data, from source to product is needed. This needs to start with NOAA/NCDC as they are ultimately responsible for data quality control.

It has been said that “humans cause global warming”. I think a more accurate statement would be “human error causes global warming”.

Note: In this post I’ve demonstrated the errors. In a later post, I hope to do some data analysis with the numbers provided to see how much effect these errors actually have. Of course anyone who wants to do this is welcome to leave links to graphics and tables. -Anthony

See these weather underground sites:
Yakutsk (Jakutsk)
and this one, is particularly interesting, because it shows a clear error in the 12:30PM and 1 PM METAR report for that day
12:00 PM -5.8 °F -9.4 °F 84% 30.33 in – SW 11.2 mph 17.9 mph N/A   Clear
UERR 010300Z 22005G08MPS CAVOK M21/M23 Q1027 NOSIG RMK QFE738 24450245
12:30 PM 69.8 °F -9.4 °F 4% 30.30 in 6.2 miles SW 11.2 mph 17.9 mph N/A   Unknown

UERR 010330Z 22005G08MPS 9999 -SN 21/M23 Q1026 NOSIG RMK QFE738 24450245

1:00 PM 68.0 °F -7.6 °F 5% 30.27 in 6.2 miles SW 11.2 mph 17.9 mph N/A   Unknown

UERR 010400Z 22005G08MPS 9999 -SN SCT100 OVC200 20/M22 Q1025 NOSIG RMK QFE737 24450245

1:30 PM -4.0 °F -7.6 °F 85% 30.24 in 2.5 miles SSW 11.2 mph 17.9 mph N/A Snow Light Snow

UERR 010430Z 21005G08MPS 4000 -SN SCT100 OVC200 M20/M22 Q1024 NOSIG RMK QFE737 24450245

Note the missing ” M” on the 1230 and 1PM reports 21/M23
Put that in this online METAR decoder:
and you get 70F for 12:30PM and 68F for 1PM man made global warming thanks to hand coded teletype report.
Pilots will know its wrong and disregard, they mostly worry about baro pressure/altimeter and winds. Temps on the ground are never as extreme as what aircraft experience in the air.
No incentive to correct this…not a big deal to aviation.
Here is what I think is going on:
1) Russian METAR is hand-coded from airports, thus prone to error. put in a minus sign for M or make an M+space+ temp/dp and you get the same thing. example:
UERR 010330Z 22005G08MPS 9999 -SN -21/M23 Q1026 NOSIG RMK QFE738 24450245 gives 70F in the online decoder above, later systems may strip the minus sign as being an invalid character in the report which is why we may not see it…or they just forget to add “M” either way, all we need is one of these per month.
2) or…character formatting western/cyrillic may contribute to missing or badly formatted characters in automated decoding.
Either way, there’s our spurious Russian warming, and why we seem to have a permanent red spot there.
Here’s what one off reading will do. The city of Yakutsk, one of the coldest cities on earth, reported a high of 94˚F on December 14th with a low of -35˚F. The average for the day, 30˚F, was some 67˚F above normal.. pushing the anomaly for the month of December from 3.6˚F above normal to 5.9˚F above normal… quite a shift!
It also happens in Antarctica:
Dome C station
Nico University of Wisconsin
Admusen Scott Station
Here is the list of sites with GHCN WMO numbers per this list:
WMO number    Station Name            Day/Month/Year of error
24266                Verhojansk                   13/11/2009
23955                ALEKSANDROVSKOE  11/12/2009
and also 01/16/2009
and 02/02/2007

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Aargh
April 18, 2010 5:20 pm

This was another top-notch quality presentation, Anthony. I really love it when you’re in top form.
I love facts. I love certainty.
Unfortunately it seems many skeptics has been self defeating by adopting the specific argument ‘no real scientists calls anything a ‘fact’ as truth can never be proven.’
This is doomed to fail. You can’t argue truth if you don’t recognize its existence. Poor Willis.
When skeptics become nihilists, they Kant do just like the university narcissists who rehearsed the same thing but more.
Honest to god, people need to sort out the fundamentals of epistemology before they hit age 5.
There is a type of person who just hates the concept of truth because they can’t tolerate anybody who is certain about anything.
They can’t tell you why this motivates them so powerfully to make missions out of attacking with any available rhetorical tool.
The reason is that reason, itself, is an existential threat to them because it enables their prey to defend against them.
it’s reason, truth and certainty of those things that they hate because they require the benefits of doubt to survive – your doubt- please note well that they are not at all uncertain about the truth of their argument that YOU must not be certain and that YOU can’t know truth – and therefore they shall deliver the gospel as revealed to them…lol
You provide the antidote, Anthony. You and Mr. Macintyre and some others – too few.

Neo
April 18, 2010 5:21 pm

Perhaps we could avoid all this stuff by just using Kevin

Graham Dick
April 18, 2010 5:21 pm

Wren (20:46:49) : “Perhaps the answer to addressing this systematic error is simply to require a sign, plus or minus, in front of each recorded value.”
That’s how it WAS done. AW made that point:- “when a minus temperature occurs, such as -10 degrees Fahrenheit, it was reported as “-10″………In the METAR report above, instead of using the normal way we treat and write negative numbers, some policy wonk decided that we’ll use the letter “M” to report a negative number. Only a bureaucrat could think like this.”

April 18, 2010 5:33 pm

From my repost of this on digg.com
http://digg.com/environment/GISS_dial_M_for_missing_minus_signs
This is quite an interesting article, not just because of its implications on historical temperature records from airports, but because it demonstrates quite nicely how human factors interact with accuracy and how _not_ designing reporting systems to take that into account can result in simple errors have a dramatic impact.
For instance if the processing software had just simply rejected reports using a ‘-‘ instead of a ‘M’ then the error would have been stopped, instead it looks like the ‘-‘ got ignored and the temp got processed as positive – whoever designed that should be given a very direct lesson in what ‘data format validation’ means.
I’ve also been doing some digging of my own around the airport temperature records, and I kept finding the reported winter mean monthly values were always slightly higher then my hourly averaged values across the month. This might explain it as the daily min/max sum to monthly mean gives a false positive value in winter potentially 24 times the weight than just summing to mean all the hourly values taken in a month.. I’ll see if I can recreate this effect..

bubbagyro
April 18, 2010 5:56 pm

Pompous:
As per Jonesy: “Milady doth protest too much, methinks”
Next milestone, for the good professor: “Alas, poor Yonesy, I knew him well, Pompous”

April 18, 2010 5:57 pm

Very good piece, Anthony. Ties together both ends of the process, from data producer through to consumer, explaining the human interpretation/conveyance stage, the changes in required data formats thru to the final data consumer/acchiver, GISS et al.


Rod Smith (09:31:56) :

The former USAF forecast center (AFGWC) ran “validators” which, among other thing compared current observations to recent observations. This (hopefully) caught the notorious problems in Siberian reports in coding very cold temperatures.

I am surprised, with the plethora of PhDs (and no doubt a goodly number of interns hired every summer to work at GISS) that GISS (or some other data aggregator) would not have implemented some means to simply check incoming data samples against previous data samples for the purposes of a rudimentary data consistency checks.
.
.

bubbagyro
April 18, 2010 5:59 pm

Sorry, I meant to address Steven. I owe a Shakespearean reference to Pompous Git.

Neel Rodgers
April 18, 2010 6:08 pm

Bruckner8 (08:00:23) :
Anthony’s entire point is that human error is causing this problem. That said, if I were in charge of the technology where this data is ultimately stored, I’d write a computer program with algorithms for sniffing out the simplest anomalies…the most obvious errors could be reviewed and corrected very quickly.
I say “more computers and less humans, please” realizing that humans create computers and the programs. It all comes down to good science.
Computers are not free of errors either. The computers that are ingesting this information and dissiminating it can be just as prone to error. How software is programmed can sometimes have this effect. I have seen it happen with winds on one of my sensors in the past. A thunderstorm collapsed and gave us 72 knots of wind (based off of a hand-held sensor). The main sensor registered 217 knots. There is a significant difference there but having a person do Quality Assurance could see this error and fix it.
The example given above of consistently hitting M27 and then jumping to M13 could have been one of those software glitches. The example where it is +20C with light snow (the -SN) would also be caught, because you will not have snow at 68F.
If one can forget to put in an “M” for Minus, they can just as easily forget to put the “-” which tells me it isnt a problem with the code so much as human nature.
So how do we fix it? The number crunching software should have a Q/A ability. Compare the observations on each side of the current one to look for significant inconsistencies such as these, and then alert a person to them so they could be adjusted/fixed accordingly. Also set it to be able to recognize variations with spaces in it.
I just think the wrong thing is being villified here. Is it the code, or is it inadequate Q/A?

April 18, 2010 6:13 pm


aurbo (14:42:51) :
In fact … the machines including the Model-15 and Model-28 page printers

page printers? The surplus Model 28’s we used in the late 70’s all used continuous roll paper … maybe ‘page printer’ refers to 8 1/2″ wide paper versus paper tape …
Model 28 info page:
http://www.baudot.net/teletype/M28.htm#M28-KSR
.
.

baahumbug
April 18, 2010 6:35 pm

Here is a quote from proff Judith Curry in November 2009
” Judith Curry November 25 2009
J. Gavin Schmidt deserves credit for what he is doing. If something is broken, give credit when somebody tries to fix it. Why on earth anyone is hiding their data is beyond me. I find it hard to believe that Phil Jones has anything to hide in this data set. sure a few little glitches may come to light, but if this happens and they get fixed, that would be a good thing. When the auditing was done of the GISS temp data set, a few minor glitches were found and fixed and frankly my confidence in the GISS temp data set went up several notches.”
Hmmmm I wonder how many notches her confidence will slip in view of this excellent analysis?

James S
April 18, 2010 6:54 pm

As an accountant I have always been taught that even minus signs can be missed so to ensure that all negatives are bracketed.
So -20 becomes (20) which becomes hard to read as a positive; even when looking through a long set of numbers.

April 18, 2010 7:16 pm

From the Teletype corporation archives, the CAA (forerunner to FAA) “coded hourly weather reports”; special symbols are noted in the format:
http://www.rtty.com/TTYSTORY/page25.jpg
.
.

April 18, 2010 7:17 pm

If meteorology/climatology were handled by real scientists instead of glorified weather “soothsayers” this problem would not occur because temperatures would be recorded using the Kelvin (absolute temperature) scale rather than the Celsius and Fahrenheit scales with their arbitrary zero points. The only thing you can have less than nothing of is money.
the Kelvin scale is used for scientific calculations in part because of problems with the properties of numbers 1.0 and less.
the use of humans to record numbers introduces a potential error that is greater than 0.25% which is the percentage of temperature change that supposedly occurred during the 20th Century

Legatus
April 18, 2010 7:24 pm

Anthony believes that calling this incorrect temperature measurment fraud is false, I disagree, heres why.
It could be quite true that the people who report this temperature sincerely believe it is the correct temperature, while the temperature may be a total fraud, and that sincerity also fraud. Imagine, if you will, a pre alchoholic. he tells himself “one drink will do me no harm” and he may be right. Later, he tells himself “one more drink will do me no harm”, and as the number of drinks and frequency of drinking increases, he comes up with more and more rationalizations like this (“it’s just social drinking”). Eventually he can be drinking heavily while still being sincere in his belief that he is not an alchoholic.
For the AGW crowd, it is like this, one little rationalization piling on another, but with new twists to furthur cover up from themselves the fraud. One of the strongest is that the little rationalizations that pile up on each other (like rounding all temperatures up, or dropping stations in areas that are colder) are done by many different people, thus the frauds are so spread out and diffuse that you can ignore them if you know where not to look. They can also reinforce their belief in their own correctness by peer pressures of all kinds, after all, all their buddies believe this (meanwhile they conveniently forget that any buddy that does not is blackballed). They can also do the standard propaganda ploy of not necissarily lying, but simply not telling the whole truth, thus they can tell themselves that they are not lying even when what they put out may be a geat big whopper, since they didn’t actually include any deliberate lies. Thus, if they don’t bother to check if the station data they get is correct, they aren’t really lying, just not bothering to find out the truth. They of course will also not check on each others work, after all, that would show a lack of trust in their buddies, possibly reasulting in bad feelings, we wouldn’t want that! It’s all about working together as a team!
Pulling together is the aim of despots and tyrannies. Free men pull in all kinds of directions. paraphrased from Lord Vetinari
They are also told many rationalizations by those who want to use AGW to gain power, and tell others these same ones, like “Choosing message frames for climate change that are consistent with the values of target groups is one important way to make the recommended behaviors or policies easier to accept.” …“Conservation messages, for example, can use an economic frame (This is an excellent way to save money); an energy independence frame (This is a means for our country to free itself from dependence on foreign oil); a legacy frame (This is a way to protect our children’s future); a stewardship frame (This is how I honor my moral obligation to protect the abiding wonders and mystery of life); a religious frame (This is a way to serve God by protecting His creation); or a nationalist frame (Innovative technology will keep our nation’s economy strong). By these repeating these rationalizations to each other and themselves, they can drown out that nagging little voice that tells them that they acyually stand to gain or lose hugely if AGW is true or false. As Thucydides wrote, men will accept without argument conclusions they find agreeable; but will bring all the force of logic and reason against those they do not like.
Plus, admitting that they have been wrong and are now hugely wrong and have been for many years would make them feel like what, and would cause others to think of them how? Global warming has now been so strongly supported for so many years by so many different institutions (like the press) that admitting falsity now would simply be to costly. As Upton Sinclair once said: “It is difficult to get a man to understand something when his job depends on not understanding it.”
And finally, they are supported but that largest of rationalizations, the fact that if AGW is true they become the saviors of the world. Now who wouldn’t want to be known as that? It is, in essence, “the big lie”, and thus more likely to be beieved by many than a small one. “Have you noticed, once you have succeeded in convincing a man of something incredible, he believes it with an enthusiasm that he wouldn’t dream of showing for an obvious, simple fact?” – Sir Harry Flashman. Basically, for its proponents, AGW feels good, so they keep doing it, and non AGW feels very bad, so they do anything to avoid admitting it. They can cover up that basic fact with convoluted rationaizations like “post normal science” and such so that they don’t ever have to admit it to themselves.
In short, they believe it the same way an alchoholic sincerly beleives one more drink will do him no harm.
It is also supported, or at least not opposed, by the majority now who have become so apathetic that they don’t bother to check it out for themselves, after all, you only need fool some of the people some of the time. “The opinion of ten thousand men is of no value if none of them know anything about the subject.” —Marcus Aurelius. And of course, with sheep like that, it’s just too big of a temptation not to lead them about: “The whole aim of practical politics is to keep the populace alarmed (and hence clamorous to be led to safety) by menacing it with an endless series of hobgoblins, all of them imaginary” -H.L. Menchen. In short, the AGW crowd is now acting like the alchoholic, and the populace is now like the co-dependant.
So I believe this recent “warmest on record” month IS a fraud, it’s a very carefully disguised fraud, disguised so well even the ones doing it can tell themselves they are sincere. And the AGW crowd has SO much invested in this that they cannot stop now, I expect the next moves will be to cover themselves by silencing the opposition. Someone is going to wake up in a gutter, and they don’t want it to be themselves.

Wren
April 18, 2010 7:29 pm

Perhaps I am wrong, but I didn’t get the impression plus signs formerly were used in front of the positive numbers.
If missing negative signs(“-” or M) and other errors tend to bias the GISSTEMP global temperature trend upwards, something else must be offsetting the effect, since this trend does not diverge from the RSS and UAH trends. Looking at the three over at woodfortrees, GISSTEMP appears slightly closer to RSS and UAH recently than it was in 1978 when the latter two began.
http://www.woodfortrees.org/plot/hadcrut3vgl/last:360/offset:-0.146/mean:12/plot/uah/last:360/mean:12/plot/rss/last:360/m

Wren
April 18, 2010 7:32 pm

Graham Dick (17:21:43) :
Wren (20:46:49) : “Perhaps the answer to addressing this systematic error is simply to require a sign, plus or minus, in front of each recorded value.”
That’s how it WAS done. AW made that point:- “when a minus temperature occurs, such as -10 degrees Fahrenheit, it was reported as “-10″………In the METAR report above, instead of using the normal way we treat and write negative numbers, some policy wonk decided that we’ll use the letter “M” to report a negative number. Only a bureaucrat could think like this.”
====
I’m sorry Graham Dick. My previous post was a reply to your comments above, but I forgot to address it to you.

Neo
April 18, 2010 7:33 pm

Haven’t we seen this story before …

(CNN) — NASA lost a $125 million Mars orbiter because one engineering team used metric units while another used English units for a key spacecraft operation, according to a review finding released Thursday.

April 18, 2010 7:38 pm

A major problem with using airport reporting stations in snow prone areas is that airports have to clear runways so planes can take off and land without sliding all over the place. Snow covered areas reflect sunlight back into space. Pavement converts sunlight into heat. snow piles on cleared pavement will melt from the heated pavement even when the air temperature is below freezing and the water will remain liquid until the sun sets. Cleared pavement transfers some of its heat to adjacent snow covered areas melting the snow and allowing the ground to heat by absorbing sunlight. You can see this in your yard if you clean the snow off your sidewalk.

Rod Smith
April 18, 2010 7:40 pm

aurbo: Thank you — maybe the old brain is functioning after all. I remember those old low-baud rate days well, and service “A” too. The USAF once tried to hook up to a country in South America during the 60’s, and they wanted to operate at 15 baud!
Thanks again.

April 18, 2010 8:24 pm

Reference the use of a teletype and a SECO box (Sequential Control) for generating weather reports:
http://docs.lib.noaa.gov/rescue/wb_circular_ltrs/Qc875u5u651952.pdf
The following is an excerpt from: Discussion of CAA/Weather font set (Note: A minus sign seems to exist in this character set.)

This typewriter-based, serif, mono-spaced font is similar, but not exactly, to the actual Teletype typeboxes, that where used initially by the Civil Aviation Agency (CAA), subsequently reorganized as the Federal Aviation Administration(FAA), in the various electro-mechanical Teletype (TTY / TWX) machines. These teletypes were used by Air Traffic Controllers at over 360+ Flight Service Stations facilities, the U.S. Weather Bureau/Stations, international weather stations, military and many other facilities throughout the world for communications and weather reporting/transmission purposes.
The main unique differences from the standard teletype is that the CAA/FAA typeboxes included eight (8) wind direction arrows and four (4) cloud cover symbols. In addition, several letters were slightly “bowed” outward at the sides from standard teletype typeface(s). No lower case letters were used; instead the typeboxes were shifted between LTRS (Letters) and FIGS (Figures). The teletype, such as the ASR-28 model used a 5 level Baudot coded paper tape, a nylon-cloth ribbon, ran at a 110 baud rate, or about 60 words per minute and the typeboxes only had 64 characters available (including CR, LR, SP, BEL, NUL, etc.).
Around 1985, due to the computer automation upgrades using the new standard ASCII coding, all weather symbols were removed and replaced with text-based descriptors. In addition, the consolidation of 360+ Flight Service Stations to the new 64 Automated Flight Service Stations (AFSS) in the mid to late 1980’s, made the slow teletype system(s) obsolete and was removed. About 2005, all the FAA Flight Service Station facilities/personnel were sold (?) by the U.S. Government to Lockheed-Martin Corporation and are expected to be further consolidated to less than a handful nationwide.

Interesting account of a weather plotter:
http://forum.keypublishing.com/showpost.php?s=d86e866457d920c9f83cb46ad962017f&p=1469942&postcount=7

Pompous Git
April 18, 2010 8:37 pm

FrankK (12:52:13) :
“I commented earlier about por [sic] old Tasmania just below Australia being a nonsense “hotspot” in the GISS figure. I notice there is no such hotspot but normal temps in the satellite diagram for Tasmania. That makes much more sense.”
Dunno about “poor old Tasmania”. We just had a ripper of a summer after managing to not notice the Global Financial Crisis. Best summer since the sixties for those who remember back that far. If this is Global Warming, bring it on 🙂
And while talking about globes, Tasmanian Tim Bowden relates the following aphorism:
“Tasmania is the testicle of the Nation. It infuses it with vim and vigour. What a pity there aren’t two of them.”

Pompous Git
April 18, 2010 8:50 pm

Neo (17:21:39) :
“Perhaps we could avoid all this stuff by just using Kevin”
Us Australian sceptics avoid all this stuff by perceiving it as just P Wong 😉

April 18, 2010 9:23 pm

This document:
http://docs.lib.noaa.gov/rescue/wb_circular_ltrs/Qc875u5u651954.pdf
pdf page 30 Circular Letter #10-54 describes “Service ‘A’ Transmissions of Aviation Weather Forecasts” re: teletype circuit loading.
Plus signs and Minus signs (as well as a few other special symbols) seem to be in evidence.

RobB
April 18, 2010 9:40 pm

Meticulous work, with disturbing implications.
Especially so given the low number of reporting stations in the Arctic, including northern Canada.
Thanks Anthony,

Pompous Git
April 18, 2010 9:41 pm

Aargh (17:20:20) :
“There is a type of person who just hates the concept of truth because they can’t tolerate anybody who is certain about anything.”
Enlighten me please as to the Nature of this Truth. Is it the Coherence Theory of Truth, the Correspondence Theory of Truth, the Pragmatic Theory of Truth, or one that I’ve not heard of?
Oh, and why would anyone “hate” your theory of truth without knowing which particular theory of truth you espouse?
Just curious…