Ocean-Coast-Continent Interaction and Rain Echoes Observed by Radar

Given the geographical characteristics of Bordeaux, the coastal radar installed in this region offers an opportunity to put in evidence the ocean-coast-continent interaction and the observation of the rain fields at the landsea transition. To this effect, the study site was divided into three windows of 60x180 km delimiting the ocean west of the radar and the continent to the east. A Comparative analysis of daily surfaces of rain echoes for the three study areas showed that during a very dry period the rainfall over the sea is reduced of half compared to those of the coast. On the other hand, the surfaces of rain echoes are evolving in the same way for all three areas and are more important over coast and continent that over sea, the difference is 23%. Almost the same difference was found for the rainfall rate recorded during the summer (June-September), the observation period the most favorable for our study. This difference was also verified using the model defined in recommendation ITU-R P.837-3 to calculate the rain intensity exceeded for p% for the average year and for a given location.