Editing Tide (section)

=== Reference levels ===
{{see also|Chart datum#Definitions}}
[[File:Tide terms.png|thumb|upright=3.65|center|Illustration by the course of half a month]]

The following reference tide levels can be defined, from the highest level to the lowest:
* ''[[Highest astronomical tide]]'' (HAT) – The highest tide which can be predicted to occur. Note that meteorological conditions may add extra height to the HAT.
* ''[[Mean high water springs]]'' (MHWS) – The average of the two high tides on the days of spring tides.
* ''Mean high water neaps'' (MHWN) – The average of the two high tides on the days of neap tides.
* ''[[Mean sea level]]'' (MSL) – This is the average sea level. The MSL is constant for any location over a long period.
* ''Mean low water neaps'' (MLWN) – The average of the two low tides on the days of neap tides.
* ''[[Mean low water springs]]'' (MLWS) – The average of the two low tides on the days of spring tides.
* ''[[Lowest astronomical tide]]'' (LAT) – The lowest tide which can be predicted to occur.<ref>{{cite web |title=Definitions of tidal terms |url=http://www.linz.govt.nz/hydro/tidal-info/tidal-intro/definitions |website=Land Information New Zealand |access-date=20 February 2017 |archive-date=30 August 2014 |archive-url=https://web.archive.org/web/20140830114240/http://www.linz.govt.nz/hydro/tidal-info/tidal-intro/definitions |url-status=live }}</ref>