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Charts - Misc charts: Difference between revisions
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== Thermal Seasons == | == Thermal Seasons == | ||
[[File:Thermal Seasons.jpg|thumb|right|Thermal Seasons]] | [[File:Thermal Seasons.jpg|thumb|right|Thermal Seasons]] | ||
<small>'''NOTE:''' This chart will only produce when a year starts on the first of january (Northern hemisphere) or first of July (Southern hemisphere) So if you start your station on 22 August 2022, this chart won't show 2022 (i.e. ist is blank) but the first sesasons chart will show on 1 January 2023). You can hide it by setting the relevant parameter to false) | |||
</small> | |||
A variation on the [https://jussilanet.com/chartstermiset.htm Thermal Seasons] chart by [https://cumulus.hosiene.co.uk/memberlist.php?mode=viewprofile&u=16853 @Pes]. This interesting chart, together with the Temperature Sum and the Growing Degree Days it forms the set of Agriculture related charts, displays the proportional contribution of the seasons in the year where the boundaries between the seasons is simply defined by average temperature of the day. | A variation on the [https://jussilanet.com/chartstermiset.htm Thermal Seasons] chart by [https://cumulus.hosiene.co.uk/memberlist.php?mode=viewprofile&u=16853 @Pes]. This interesting chart, together with the Temperature Sum and the Growing Degree Days it forms the set of Agriculture related charts, displays the proportional contribution of the seasons in the year where the boundaries between the seasons is simply defined by average temperature of the day. | ||
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At least two times there was a discussion on the forum about the way the daily average for temperature was or should be calculated (see [https://cumulus.hosiene.co.uk/viewtopic.php?p=138513#p138513 here] and [https://cumulus.hosiene.co.uk/viewtopic.php?p=152909#p152909 here]). CumulusMX uses an ''integration method'' which means it samples the temperature continuously at the sampling frequency and stores the average of those samples at the logging frequency. It creates the sum of the logged entries and at the end of day it divides them by the number of observations giving the arithmetic average of all values logged which acts as an estimator of the physical average. | At least two times there was a discussion on the forum about the way the daily average for temperature was or should be calculated (see [https://cumulus.hosiene.co.uk/viewtopic.php?p=138513#p138513 here] and [https://cumulus.hosiene.co.uk/viewtopic.php?p=152909#p152909 here]). CumulusMX uses an ''integration method'' which means it samples the temperature continuously at the sampling frequency and stores the average of those samples at the logging frequency. It creates the sum of the logged entries and at the end of day it divides them by the number of observations giving the arithmetic average of all values logged which acts as an estimator of the physical average. | ||
<math>(Max+Min)/2</math> is used with the argument | <math>(Max+Min)/2</math> is used with the argument that comparison with observations from before the computer era must be made. Note that the KNMI (the Dutch Meteorological Service) takes hourly measurements so there is no consistency between countries to start with. | ||
As an argument in this discussion this chart was made to make the difference between the institutional method and the Cumulus Integral Method visible. What is shown is the Cumulus Method Daily Average Temperature (one minute sampling): <math>(\sum_{minute=1}^{1440} {(Temp\ measurement)) \div 1440}</math>, the <math>(Max+Min)/2</math> and the difference between the two. It is clear that the first is the more accurate estimator of the two sample estimators (note they both are estimators for the statistic <math>average temperature of the day</math>). | As an argument in this discussion this chart was made to make the difference between the institutional method and the Cumulus Integral Method visible. What is shown is the Cumulus Method Daily Average Temperature (one minute sampling): <math>(\sum_{minute=1}^{1440} {(Temp\ measurement)) \div 1440}</math>, the <math>(Max+Min)/2</math> and the difference between the two. It is clear that the first is the more accurate estimator of the two sample estimators (note they both are estimators for the statistic <math>average temperature of the day</math>). | ||
The difference has a pretty even distributed noise around the zero line so comparison of current ''integral'' with observations from the past (for climatic studies) should be possible with statistical proof and a consolidation of past and current measurements has actually been executed by the KNMI <ref>[https://cdn.knmi.nl/system/data_center_publications/files/000/068/325/original/CNT.pdf?1495621137 The Construction of a Central Netherlands Temperature]</ref>. | The difference has a pretty even distributed noise around the zero line so comparison of current ''integral'' with observations from the past (for climatic studies) should be possible with statistical proof and a consolidation of past and current measurements has actually been executed by the KNMI <ref>[https://cdn.knmi.nl/system/data_center_publications/files/000/068/325/original/CNT.pdf?1495621137 The Construction of a Central Netherlands Temperature]</ref>. | ||
Another interesting article on the subject is below. <ref>[https://rmets.onlinelibrary.wiley.com/doi/full/10.1002/joc.6528 Sampling frequency of climate data for the determination of daily temperature and daily temperature extrema]</ref> | |||
<references/> | <references/> | ||
[[Category:CumulusUtils]] | [[Category:CumulusUtils]] | ||