Monthly sea level peak for November 2021

The lunar month’s highest tide occurred on 7th November for Waitemata harbour. Due to instrument issues, Great Barrier Island has had to be estimated for November using Waitemata harbour's measurements.


The Waitemata harbour tidal gauge measured a mean level of 1.67 metres between 9:45am and 10:00am on 7th November which is 3cmm below the Novemberr average (2015-2020). The barometric air pressure at the time of the reading was 1016.3 hPa, so when using the inverted barometric adjustment calculation method of 1cm for every 1 hPa, the projected height would have been 1.64 metres at the mean sea level pressure of 1013 hPa. More on meteorological effects on tides can be found here.


The ongoing trend between 2014 to 2021 for the Waitemata harbour sea level peak is downward. The tidal gauge data used for this analysis can be found here.


The Great Barrier Island tidal gauge was estimated due to instrument issues. The estimate based on Waitemata Harbour on 7th November is 1.17 metres between 9:00am and 9:15am on 7th November which is 1cm below the November average (2015-2020). The air pressure at the time of the reading was 1016.3 hPa, so when using the inverted barometric adjustment calculation method of 1cm for every 1 hPa, the projected height would have been 1.14 metres at the mean sea level pressure of 1013 hPa. More on meteorological effects on tides can be found here.


The ongoing trend between 2014 to 2021 for Great Barrier Island sea level peak is upward. The tidal gauge data used for this analysis can be found here.



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