Tides

lachie-awesome-surfer's picture
lachie-awesome-... started the topic in Tuesday, 13 Apr 2010 at 7:43am

when they say what the tide is i don't get the part where they say what it will be in cm like low tide 12:50 at (73cm)

i don't get what it means.

spongebob's picture
spongebob's picture
spongebob Tuesday, 13 Apr 2010 at 8:48am

It's the height above the lowest tides,but you can still get negitives like say(-10cm).It's called chart datum,the depths on maritime charts are measured from that level.Tide range is measured from that level up.

brendo's picture
brendo's picture
brendo Tuesday, 13 Apr 2010 at 8:52am

it's measured on a scale so you can tell how low the low will be etc. Tide heights change all the time depending on the moon / sun rotational cycle / gravity etc.

thelostclimber's picture
thelostclimber's picture
thelostclimber Tuesday, 13 Apr 2010 at 9:51am

this is a pretty clear explanation

http://en.wikipedia.org/wiki/Chart_datum