Diurnal: Difference between revisions

From Glossary of Meteorology
imported>Rbrandt
Line 10: Line 10:
<div class="definition"><div class="short_definition">As typically defined in meteorology: Daily, especially pertaining to actions that are completed within 24 h and that recur every 24 h; thus, most reference is made to diurnal cycles, variations, ranges, maxima, etc.</div><br/>
<div class="definition"><div class="short_definition">As typically defined in meteorology: Daily, especially pertaining to actions that are completed within 24 h and that recur every 24 h; thus, most reference is made to diurnal cycles, variations, ranges, maxima, etc.</div><br/>


<div class="paragraph">The diurnal variability of nearly all of the meteorological elements is one of the most striking and consistent features of the study of weather. The diurnal variations or range of important elements at Earth's surface can be summarized as follows: 1) [[temperature]] maximum occurs after local noon and minimum near [[sunrise]]; 2) [[relative humidity]] and [[fog]] are the reverse of [[temperature]]; 3) [[wind]] generally increases and [[veering|veers]] by day and decreases and [[backing|backs]] by night (''see'' [[heliotropic wind]], [[land breeze|land]] and [[sea breeze]], [[mountain wind|mountain]] and [[valley wind]]); 4) [[cloudiness]] and [[precipitation]] over a land surface increase by day and decrease at night; over [[water]] the reverse is true, but to a lesser extent; 5) [[evaporation]] is markedly greater by day; 6) [[condensation]] is much greater at night; 7) [[atmospheric pressure|atmospheric  pressure]] varies diurnally or semidiurnally according to the effects of [[atmospheric tides]].</div><br/> </div>
<div class="paragraph">The diurnal variability of nearly all of the meteorological elements is one of the most striking and consistent features of the study of weather. The diurnal variations or diurnal range of important elements at Earth's surface can be summarized as follows: 1) [[temperature]] maximum occurs after local noon and minimum near [[sunrise]]; 2) [[relative humidity]] and [[fog]] are the reverse of [[temperature]]; 3) [[wind]] generally increases and [[veering|veers]] by day and decreases and [[backing|backs]] by night (''see'' [[heliotropic wind]], [[land breeze|land]] and [[sea breeze]], [[mountain wind|mountain]] and [[valley wind]]); 4) [[cloudiness]] and [[precipitation]] over a land surface increase by day and decrease at night; over [[water]] the reverse is true, but to a lesser extent; 5) [[evaporation]] is markedly greater by day; 6) [[condensation]] is much greater at night; 7) [[atmospheric pressure|atmospheric  pressure]] varies diurnally or semidiurnally according to the effects of [[atmospheric tides]].</div><br/> </div>


<p>''Term updated 29 May 2020.''</p>
<p>''Term updated 19 January 2021.''</p>


{{TermIndex}}
{{TermIndex}}

Revision as of 08:28, 19 January 2021



diurnal

As typically defined in meteorology: Daily, especially pertaining to actions that are completed within 24 h and that recur every 24 h; thus, most reference is made to diurnal cycles, variations, ranges, maxima, etc.

The diurnal variability of nearly all of the meteorological elements is one of the most striking and consistent features of the study of weather. The diurnal variations or diurnal range of important elements at Earth's surface can be summarized as follows: 1) temperature maximum occurs after local noon and minimum near sunrise; 2) relative humidity and fog are the reverse of temperature; 3) wind generally increases and veers by day and decreases and backs by night (see heliotropic wind, land and sea breeze, mountain and valley wind); 4) cloudiness and precipitation over a land surface increase by day and decrease at night; over water the reverse is true, but to a lesser extent; 5) evaporation is markedly greater by day; 6) condensation is much greater at night; 7) atmospheric pressure varies diurnally or semidiurnally according to the effects of atmospheric tides.

Term updated 19 January 2021.


Copyright 2024 American Meteorological Society (AMS). For permission to reuse any portion of this work, please contact permissions@ametsoc.org. Any use of material in this work that is determined to be “fair use” under Section 107 of the U.S. Copyright Act (17 U.S. Code § 107) or that satisfies the conditions specified in Section 108 of the U.S.Copyright Act (17 USC § 108) does not require AMS’s permission. Republication, systematic reproduction, posting in electronic form, such as on a website or in a searchable database, or other uses of this material, except as exempted by the above statement, require written permission or a license from AMS. Additional details are provided in the AMS Copyright Policy statement.