mcrossley wrote: ↑Sun 08 Mar 2020 8:56 pm
Many were OK, with no change, some it made 0.1 difference to some figures. So like I said, the error on a full year was small.
Yes, it is during the year that the (small) difference is noted, especially in Spring in a non leap year, but of course some might say our climate is so wild that seasonal patterns are gone for ever?
alexlc13 wrote: ↑Sun 08 Mar 2020 9:41 pm
There has been much discussion as to whether to average months or days to get annual temperature averages. The NWS and NCEI (National Centers for Environmental Information) calculate annual temperature averages by averaging the months. It is agreed that averaging days is more accurate, but because averaging months is what has always been done historically, then that's how the calculations will continue to be made.
Thank you for that, I deduce Steve Loft knew that and therefore deliberately made his NOAA style reports work like that, as I know he was trying to imitate the USA report contact (hence the naming as "NOAA" style).
I still believe that Mark is right having swapped to the more accurate calculation for the future, it is more consistent with how other parts of Cumulus work. It is also likely to match what happens in most countries outside USA.
HansR wrote: ↑Sun 08 Mar 2020 6:05 pm
I don't really get the paragraph alternatives, but that's probably because I don't have C1. And further in that paragraph: I think the median is not very often used in meteorology and the average if the min/max temperature I think, is at best a first order estimate of the true average and nothing more.
Good to hear your opinions, as they match mine.
The page history tells me I added that paragraph on 30 May 2013, my memory is not good enough to recall the exact rationale, but I believe there was a lengthy discussion comparing two means in one of the sub-forums prior to this, with some expressing preference for one, and some for the other. I presume somebody raised the question about median, I know some users of Cumulus show median and standard deviation either in a table or on a graph on their websites. I am guessing I tried to record the balance of the views, as I said I added a lot to Wiki attempting to summarise forum discusions as back then lots of people were searching the Wiki for help (Steve at that time had a notice on forum - Please read this first - the gist of which was that people before asking for help on forum see if your question is answered on the wiki, most simple questions being in FAQ section of wiki).
a) For each day, adding maximum and minimum that day, then dividing that sum by twice times the number of days. I have seen this quoted in weather station reports, especially in the observer manual reading days, not so much with automated stations.
b) What I called then the integrated mean, applying it in the mathematical sense of combining (summing) all available values, this is what this thread has been about. In terms of Cumulus processing it is the one represented by the sum and count parameters in today.ini
In searching the forum, I found viewtopic.php?f=4&t=11905&p=95228 dating from 2014 (i.e. after that paragraph went into Wiki), that has some relevance, although its focus is on monthly not annual figures. Unfortunately, the forum won't let me see anything pre 20 May 2013, so I imagine that lengthly conversation I mentioned is lost. It is around the time that Steve Loft switched the forum onto a new platform and he observed that some content was lost.