[RegCNET] tmax and tmin

[Wm. J. Gutowski]

Dear Bi:
	Maximum wind gust every 3 hours might be useful, but let's 
see if others endorse it.

Bill

At 9:47 AM +0100 05.11.16, BI XUNQIANG wrote:
>Dear Bill, Lara, and Gao:
>
>In the next public released RegCM3 version, we will add Tmax, Tmin
>and vertital velocity (for pressure level) as the standard output.
>
>We will calculated Tmax and Tmin as the way Bill suggested (for
>every land surface step, and reset at 00 UTC).
>
>Any other fields are also necessary to be included ?
>
>Thanks and best regards,
>
>On Tue, 15 Nov 2005, Wm. J. Gutowski wrote:
>
>>Dear Lara:
>>	I am not the expert on this, but I am pretty sure that 
>>observed Tmin and Tmax are obtained primarily from min/max 
>>thermometers, which record the highest and lowest temperature 
>>attained since the last time they were reset. They are almost 
>>always reset every 24 hours, though they don't all get reset at the 
>>same time.  That is, different stations, even in the same country 
>>(or in the US, the same state) may reset their thermometers at 
>>different times of the day.  This can induce a small bias in one 
>>station's climatological averages compared to what it would get if 
>>it reset at another time.  This is documented in the literature 
>>somewhere, though I don't have the reference myself.
>>	Using the 3-hourly output will tend to reduce the diurnal 
>>temperature range you get because that is probably not sampling the 
>>extremes of the day, though I have not seen this reduction 
>>tabulated by anyone, and it probably depends on location and 
>>season.  Including a computation of the true daily min/max 
>>temperature would be just a few lines of code, and some of us 
>>RegCNETers have undoubtedly done it for their version of the code - 
>>we really should have it as part of the standard model, I think. 
>>There would still be the question of what time of day to "reset the 
>>thermometer", but in model intercomparisons I've been part of, we 
>>typically agree to go from 00 UTC - 00 UTC.
>>
>>Bill
>>
>>At 11:32 AM -0800 05.11.14, Lara Kueppers wrote:
>>>Hi-
>>>Awhile back I asked how Tmin and Tmax in the SRF output file were 
>>>calculated. Here is Nellie's recent reply, in case anyone else is 
>>>interested.:
>>>
>>>"Hi Lara,
>>>
>>>I just verified this with Bi...Tmin and Tmax are calculated from 
>>>the BATS output, so if you have the model output to the SRF file 
>>>every 3 hours, then that is what the min and max are calculated 
>>>from.  Bi thinks this is a better way to do it since min and max 
>>>temp observations are generally taken from 3 or 6 hourly obs.  You 
>>>can increase the frequency of the srf output variables (in the 
>>>regcm.in file) to see how much of difference it would make in the 
>>>diurnal temp range. "
>>>
>>>--
>>>~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*
>>>Lara M. Kueppers, PhD
>>>Postgraduate Researcher
>>>Department of Earth Sciences
>>>University of California, Santa Cruz
>>>1156 High Street
>>>Santa Cruz, CA  95064
>>>USA
>>>
>>>831.459.3504 ph
>>>831.459.3074 fax
>>>kueppers at pmc.ucsc.edu
>>>
>>>_______________________________________________
>>>RegCNET mailing list
>>>RegCNET at lists.ictp.it
>>>https://lists.ictp.it/mailman/listinfo/regcnet
>>
>>
>>--
>>~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>William J. Gutowski, Jr.
>>3021 Agronomy Hall
>>Dept. of Geological and
>>     Atmospheric Sciences
>>Iowa State University
>>Dept. of Agronomy
>>Ames, Iowa  50011-1010
>>
>>gutowski at iastate.edu
>>Tel:1-515-294-5632
>>Fax:1-515-294-2619
>>http://www.ge-at.iastate.edu/
>>http://rcmlab.agron.iastate.edu/
>>~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>
>>_______________________________________________
>>RegCNET mailing list
>>RegCNET at lists.ictp.it
>>https://lists.ictp.it/mailman/listinfo/regcnet
>>
>
>~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>~  Dr. Xunqiang Bi         email:bixq at ictp.it  ~ ~  Physics of 
>Weather and Climate Group        ~
>~  The Abdus Salam ICTP                        ~
>~  Strada Costiera, 11                         ~
>~  P.O. BOX 586, 34100 Trieste, ITALY          ~
>~  Tel: +39-040-2240302  Fax: +39-040-2240449  ~
>~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
William J. Gutowski, Jr.
3021 Agronomy Hall
Dept. of Geological and
      Atmospheric Sciences
Iowa State University
Dept. of Agronomy
Ames, Iowa  50011-1010

gutowski at iastate.edu
Tel:1-515-294-5632
Fax:1-515-294-2619
http://www.ge-at.iastate.edu/
http://rcmlab.agron.iastate.edu/
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~