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| About
the tides what causes them? updated Aug 08
Our shores are submerged most of the time. Safe and wet underwater, amazing plants and animals live out their lives unseen. The non-diver and casual visitor can only have a 'dry' and easy view of this rich intertidal zone when it is exposed during low srping tides. The lower the tide, the larger the expanse of shore that is exposed. The coastal area affected by the tides is called the intertidal zone. Tides in Singapore: Singapore has two low tides and two high tides a day. The height of the tide is not the same every day. High and low tides do not happen at the same time every day, and the highest and lowest tide level change every day. What affects the tides? The timing and height of tides are influenced by the gravitational effects of the moon, and to a lesser degree, that of the sun (because it is much further away). Spring Tides: At some times of the month, the difference between the lowest (and highest) tides is much larger. Such tides are called spring tides. During a full moon or new moon, the moon and sun are lined up. Their combined gravitational effect results in an extra high and extra low tide. This is called a spring tide because the water appears to spring up. In Singapore, these low spring tides usually occur twice a month and usually for only a few hours each time. Since the tides are much lower during spring tides, a much larger expanse of shore is exposed during this time. Neap Tides: At other times of the month, the difference between the highest and lowest tides are not so great. These tides are called neap tides. At a quarter moon or three-quarter moon, the sun's gravity works at right angles to that of the moon. This results in a smaller difference in height between the low and high tide. This is called a neap tide. In Singapore, low spring tides generally occur in the late afternoon to early evening for six months. This switches to early morning for the next half year. |
Changing
views of Chek Jawa
as the tide falls to a low spring tide.
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The
tide height is not the same every day.
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Online tide tables for Singapore
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