is an option for functions like AirTemperatureData that determines the units of the result.


UnitSystem
is an option for functions like AirTemperatureData that determines the units of the result.
Details

- The following settings for UnitSystem can be used:
-
"Imperial" return results in imperial units "Metric" return results in metric units - Specific units depend on the function and property used.
- The default setting for UnitSystem is determined by your $GeoLocation and can be reset by adjusting $UnitSystem.
Examples
open all close allBasic Examples (1)
Control whether results are returned in metric or imperial units:
Changing units can also be accomplished with UnitConvert:
Properties & Relations (2)
Quantities returned for station properties can be adjusted with UnitSystem:
The default value is determined by $UnitSystem, which is set by your computer's location:
Possible Issues (2)
WindDirectionData does not return basic results in metric or imperial units:
Improper settings for UnitSystem are ignored:

History
Text
Wolfram Research (2014), UnitSystem, Wolfram Language function, https://reference.wolfram.com/language/ref/UnitSystem.html.
CMS
Wolfram Language. 2014. "UnitSystem." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/UnitSystem.html.
APA
Wolfram Language. (2014). UnitSystem. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/UnitSystem.html
BibTeX
@misc{reference.wolfram_2025_unitsystem, author="Wolfram Research", title="{UnitSystem}", year="2014", howpublished="\url{https://reference.wolfram.com/language/ref/UnitSystem.html}", note=[Accessed: 15-August-2025]}
BibLaTeX
@online{reference.wolfram_2025_unitsystem, organization={Wolfram Research}, title={UnitSystem}, year={2014}, url={https://reference.wolfram.com/language/ref/UnitSystem.html}, note=[Accessed: 15-August-2025]}