Friday, 8 March 2013

Fieldwork without clear overwash evidences

On January 19th, there was a red alert for waves on the Portuguese coast. In the Algarve, Hs reached 4.5 m with maximum wave height exceeding 8 m. We went to Albufeira groin to undertake a fieldwork campaign within another national project (SPACE). An electromagnetic current meter and 5 pressure transducers were deployed, and cool videos were recorded during the overtopping of the coastal structure.
On January 21st, we made a post-storm survey on Barreta Island, expecting serious overwash all over the island.

Top of the barrier, looking westwards.

 However, we found almost no evidences of overwash. What we did find was significant aeolian rework of the barrier surface.
Aeolian ripples on the bare sand surface.
Now the questions are: Did overwash occur? Did sand transport by wind cover overwash evidences afterwards? We think it is difficult to assume that this area was not overwashed under such energetic waves, but we have no way to prove it. The lesson is to try our best to do fieldwork within the next 24 hours after overwash is supposed to occur.

Meanwhile there was a fishing contest in Barreta Island.

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