Because tides cause currents which the sailor must be aware of and they also change the depth of the water under the boat. Sailors must ensure that they do not ground.
It can be a sign of bad weather
It can be a sign of bad weather
hurricans
hurricans
It can be a sign of bad weather
hurricans
It can be a sign of bad weather
It can be a sign of bad weather
hurricans
hurricans
hurricans
It can be a sign of bad weather