Tidal Regime

Question 1

What is the spring tide regime for Southampton?

Answer 1

5 metre tidal range

Floods for 2 hours
Young flood stand for 2 hour
Floods for 3 hours - 1st HW
Ebb/slack for 1.5 hours
Slack for 1.5 hours - 2nd HW
Ebb for 3 hours - LW

Question 2

What is the neap tidal regime at Southampton?

Answer 2

1.5m tidal range

3 hour flood
2 hour slack
4 hour ebb
3 hour slack/slight flood

Question 3

What is the young flood stand?

Answer 3

2 hours after LW the flood slackens off considerably for 2 hours before an accelerated flood tide

Question 4

What causes the short ebb tide?

Answer 4

The double high water coupled with the young flood stand result in a long flood period leaving only 3-4 hours for the ebb. This results in a faster velocity ebb current.

Question 5

What causes the double high water?

Answer 5

The friction, irregular depths and width restriction of the English Channel prevent the water flowing freely and cause additional HW/LW oscillations producing the double high water experienced at Southampton.

Question 6

What causes the early Westward turn of the tide in the Solent?

Answer 6

The tidal range East of IOW is double that of the Western IOW. When the Eastern end tide becomes higher than the Western end, a westerly tidal current develops 2 hours before the actual HW.

Question 7

What is the Southampton tidal regime at Dockhead?

Answer 7

Mean HW spring 4.5m
Mean HW Neap 3.7m
Mean LW Spring 0.5m
Mean HW Neap 1.8m

Question 8

Where are the tide gauges?

Answer 8

37 Berth
Calshot
Marchwood Pile
Ocean Dock