Temperature (and humidity) measurement: Difference between revisions

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=How Cumulus software handles Temperature and Humidity=
Cumulus expects all stations to report a minimum number of parameters including outside temperature and relative humidity. Some weather station types also report wind chill, dew-point temperature, and other derivatives related to temperature and/or relative humidity. Cumulus is able to calculate wind chill, dew-point, and other derivatives (and if any of these are available from your station, you can choose whether to use the value from station or the value Cumulus calculates).
The type of weather station used determines which parameters are reported by that station and which need to be calculated by Cumulus. If Cumulus 1 is using temperature in a calculation of parameters like dew-point or apparent temperature, then for most stations it will apply any calibration settings to the temperature read from the station before using it in that calculation. Similarly if humidity is read from the station, the calibrated value is used in subsequent calculations. See the support forum for further information e.g. for Instromet stations, Cumulus 1 calculates the relative humidity from the reported wet bulb, and dry bulb, temperatures, the uncalibrated values of temperature and (calculated) humidity are then used to calculate dew-point.
 
If Cumulus (1 or MX) is using "outside temperature" in a calculation of parameters like dew-point, or apparent temperature, then for most stations it will apply any calibration settings to the temperature read from the station before using it in that calculation. In Cumulus 1, uncalibrated temperature values are used from Instromet, see support forum for more details.
 
The type of weather station used determines which parameters are reported by that station and which need to be calculated by Cumulus. If Cumulus 1 is using temperature in a calculation of parameters like dew-point or apparent temperature, then for most stations it will apply any calibration settings to the temperature read from the station before using it in that calculation. Similarly if humidity is read from the station, the calibrated value is used in subsequent calculations. See the support forum for further information e.g. '''for Instromet stations''', Cumulus 1 ''calculates the relative humidity from the reported wet bulb, and dry bulb'', temperatures, the uncalibrated values of temperature and (calculated) humidity are then used to calculate dew-point.
 
== Logged values ==
At the logging interval you set, Cumulus logs outdoor temperature, dew-point, and relative humidity; plus a whole host of values derived from them (and from wind speed), in [[Standard_log_files]], with separate files for each month.
 
Optionally, measurements from extra sensors can be logged in [[Extra_Sensor_Files| extra monthly files]]. For Oregon Scientific stations, temperature readings from one extra sensor can optionally replace the main sensor for "outdoor temperature", see [[Webtags#Web_tags_mentioning_.28outside.29_temperature|here]]for details.
 
Optionally, but only in Cumulus 1, indoor measurements can be logged in [[speciallog.txt|a special ongoing log]].
 
From release 3.12.0, MX maintains a [[Cumulusmx.db|database table]] that can hold temperatures at one (assuming MX has been left running) minute intervals for the last 7 days.
 
==Cumulus Calculated Parameters==
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Note this means that Cumulus 1 and MX log files have a continuity break in dew point values when you migrate from one flavour to another.
 
 
 
[[Humidex]] and [[Wind chill]] and [[Heat index]] and [[#My heat index/humidex/wind chill is the same as my temperature]]
 
[[Apparent temperature]]
 
It uses a formula from the Australian BOM - http://www.bom.gov.au/info/thermal_stress/#atapproximation
 
Look up [[Humidex]], [[Wind chill]], [[Heat index]], [[Apparent temperature]], [[Feels Like|Feels Like temperature]], [[Heat/cold degree days and Chill hours]], [[Average temperature]],
Note that the version used is the one that doesn't take into account solar radiation.
[[Extra_Sensor_Files|Extra temperatures]] for details about the various derivatives.
 
[[Heat/cold degree days and Chill hours]]
 
[[Average temperature]]
 
[[Extra_Sensor_Files|Extra temperatures]]
 
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[[Category:Terminology]]
History:
<br>
* Created: [[User:Sfws|Sfws]] 00:34, 29 November 2012 (UTC) for legacy Cumulus
* Amended: [[User:Sfws|Sfws]] ([[User talk:Sfws|talk]]) 19:49, 31 July 2021 (UTC) to also cover MX as at 3.12.0
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