Tides Flashcards
New moon to 1st quarter
waxing crescent
springs occur how many days after a full and new moon?
2 days
full moon to last quarter
waning gibbous
If we can see the moon and stars, is it likely to be high or low pressure?
high pressure
what symbol is used in the almanac for a new moon?
black filled circle under the date and day of week
last quarter to new moon
waning cresent
What is the tide called when you are going from a high to low tide?
ebb tide
What are Spring tides?
The highest high tides and lowest low tides.
Occurs twice in the orbits of the moon and earth when the moon is between the earth and the sun (new moon) and when the earth is between the moon and sun (full moon).
On average, how many minutes later do tides get each day?
50 min
Tidal Diamond table on chart
HW -6 thru HW +6
Set in degrees true
Spring tide
Neap tide
If we have low pressure on the south coast of England, what kind of wind is likely and which direction will it come from?
Southwesterly wind
What are Neap tides?
Lowest high tide and highest low tide.
Occur twice when the moon is at a right angle to the earth and sun. These are the lowest tides.
If it’s overcast or raining, is it likely to be high or low pressure?
low pressure
A waning moon has what shape?
Letter ‘C’
What do you call a place that has two high tides during a 24 hour period?
Semi-diurnal
How do you find the range of the tide?
Subtract the low tide from the high tide
A waxing moon has what shape?
Letter ‘D’
How to know which tidal curve to use
Determine range
HW - LW
Compare this to the Mean HW Springs and Neaps on the tidal curve to determine which you are closest to.
Full moon to new moon
waning (reducing)
What do you do if the tidal range is significantly larger or smaller than Springs/Neaps Mean?
Range calculated by you / MHWS or MHWN
and then multiply this by the tide you calculated using the tidal curve.
Tidal Stream Atlas
Tidal set is indicated by arrows. You can use your chart plotter to figure out the degrees. Align plotter with the arrow closest to where you want.
1st two numbers are for Neaps
2nd 2 numbers are Spring rate
what symbol is used in the almanac for a full moon?
unfilled circle under the date and day of week
1st quarter to full moon
waxing gibbous
What do you call a place that has only one high tide during a 24 hour period?
Diurnal
How long is a lunar month?
29.5 days
New moon to full moon
Waxing (growing)
For Dayskipper exam, which tides will you have to calculate?
Springs, Neaps, or Midway between
What is the tide called when you are going from a low to high tide?
flood tide
If we have high pressure on the south coast of England, what kind of wind is likely and which direction will it come from?
Light northerly winds
