Thursday, August 2, 2018

Fairbanks Experiment Farm: 107 Years

UAF published an interesting little article the other day about the long and valuable record of weather observations from the university's Experiment Farm:

https://news.uaf.edu/alaskas-longest-running-weather-station-to-be-honored/

In honor of the wonderful history of climate data from this site, here's a quick look at summer temperatures since 1911.  A few of the years are missing rather a lot of data (up to a month's worth in the 3-month period), but I've included those years in the chart anyway.


Just like at many other long-term climate observing sites, there's a more pronounced long-term warming trend in daily low temperatures than in daily high temperatures, and in fact there's essentially no trend in the high temperatures.

One feature of the chart that stands out is the rash of very high temperatures in 1915-1919, including 95°F in June 1915 and 99°F in July 1919.  Of course the June 1915 heat wave was the one that produced 100°F at Fort Yukon, and the Fairbanks observer recorded a daily minimum temperature of 76°F in the same event.

If this 76°F low temperature were believable, it would almost certainly be an all-time state record for highest daily minimum, and at first glance it might seem plausible because of the magnitude of the heat wave and the date on the calendar: June 26, a suitable date for very high overnight temperatures.  Unfortunately, however, the report appears to be incorrect, because marble-sized hail and 0.18" of rain were observed on the same day, and these surely would have brought the temperature to well below 76°F.  The relevant portion of the June COOP form is copied below.

As an aside, Rick Thoman has previously shown that the 99°F in 1919 is also wrong; the all-time heat record for Fairbanks stands at 96°F, observed in 1969.



9 comments:

  1. Interesting stuff. Concerning the 76F low in 1915, do you know the time of day the observations were taken?

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  2. 6pm local time, according to the form.

    https://www.ncdc.noaa.gov/IPS/coop/coop.html

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    1. Just trying all angles to see if a low of 76 could be possible... The previous night might have been very warm (low of 76) due to the general heat and reported NE wind providing some downslope. The thunderstorm might have just happened...too close to the 6 pm ob time to cool it off below 76 by 6 pm. 20 degrees of cooling is a lot even with a thunderstorm.

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    2. An overnight low of 76F is within the realm of possibility: Fairbanks has had several other events with overnight temps staying in the 70s. However, a low of 76F with hail and 0.18" of rain seems beyond the bounds of plausibility to me, so I would require extraordinary supporting evidence. Given even the lack of at obs temps on the form, that would have to come from elsewhere.

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  3. That farm is quite an enterprise. I've watched it grow since 1967 and today it's populated with Reindeer plus both feed and experiment crops. The Georgeson Botanical Garden nearby is a delight to visit and the music events are a treat.

    "Moving on steady" describes their efforts and contribution to Alaska's climate, animal, and agricultural studies.

    Gary

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  4. One interesting factoid: the first inspection of the Ag Farm station that survives is from 1917, and it says that observations began in the summer of 1905. This can't be correct as stated, since the Ag Farm was not established until after May 1906. However, the July 1911 form is complete from start to finish and has no indication of being the start of the obs program. I've checked the National Archives, which does have quite a few pre-1920 cooperative observation forms for Alaska (including the previously "lost" Fairbanks forms for August 1909 and July 1914). There's no sign in what's online of any Ag Farm climate observations prior to July 1911, but it is quite possible that in somewhere there is old paper records waiting to be rediscovered.

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    1. Thanks Rick, indeed that's quite interesting. NCEI provides coop forms under "University Exp Stn" back to 1904, and all of the forms back to October 1904 had "University" written on them but then crossed out at some point. Do we know anything about where these observations were taken? It sounds like you think they are not from the Ag Farm.

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    2. Prior to July 1911 the coop observations were "downtown"; the observers were people associated with the Episcopal Church. Rev. Hudson Stuck signed the very first form in September 1904.

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