Christmas day for 2011 is expected to be a wet, with NEA issuing warnings of localized flash floods with high tides that coincide with rains from North East monsoon.
The rains did not discourage us from camping on Christmas eve. It have been a magical night for us in the past. Once 3 piglets came out from the bush and came near us.
Despite heavy rain forecasts, the rains were however light. We were able to walk to the jetty to see if the anglers were lucky. 2 tourists with luggage were stranded, they arrived late at 10pm and there are no transport to the Ubin only resort 2.5km away. Fortunately we were able make phone contacts which must been a great relief for them.
There was another surprise waiting for us when we headed back to our camp. We found the village square ankle deep in seawater that rose with the tide. This is unexpected as high tide for the night was 3.36m, which is not as high compared the year high of 3.65m on 20 Feb 2011.
Flooding on Christmas eve – Picture by Andy Ho
Tides pushing seawater into Ubin village on 20 Feb 2011
Googling turn out a treasure trove of information. Sea-level at Straits of Johore (between Johore and Singapore) are higher compared to other parts of Singapore due to North-east monsoon winds pushing water and currents into the straits, which is further blocked by Singapore-Johore causeway.
Sea level anomalies higher than 30cm would result in the flooding we observed that night. Checking MPA records for Tanjong Pagar tide station for the same night also confirmed tide anomaly of +0.34m. The reverse of -0.2m would occur during south-west monsoon when the straits become a shelter instead.
We saw earthworms wriggling to higher surface to escape saltwater. The effect can be catastrophic as seawater pushes further inland. Durian trees and other land plants die when their roots are submerged.
Along with global warming and rising sea levels causing frequent floods, monsoon surges is another major factor as our island state struggles to contain and manage.
