Wave Climate Variability along the Coastlines of Senegal over the Last Four Decades ADES
Variabilité du climat de vague le long des côtes sénégalaises au cours de 4 dernières décennies
Résumé
Knowledge of wave climate is essential for efficient management of the world's coastal areas. Senegal is a relevant case given its high coastal vulnerability to energetic wave conditions. This study investigates wave climates along the coastal zone of Senegal based on a new high-resolution hindcast covering the period 1980-2021. This study evaluates the average, seasonal and extreme values for the wave significant heights (Hs), periods (Tm02/Tp) and mean directions (DIR). In boreal Winter, the wave climate is dominated by swells coming from the North-Atlantic lows, while in boreal Summer, the Southern Coast (from Dakar to Casamance) is exposed to swells generated in the South-Atlantic Ocean. Throughout their refraction around Dakar Peninsula, NW swells rotate by ~100° from NW to SW, while their Hs is roughly halved when reaching the Southern Coast of Senegal. Over the studied period, trends in Hs are weak (~0.6 cm.decade -1 ) on the Northern Coast, double on the Southern coast (~1.2 cm.decade -1 ), mostly due to an increase during boreal Summer (2 cm.decade -1 ). The wave periods show weak trends (~0.05 s.decade -1 ) and DIRs show weak counterclockwise rotation (-1°.decade -1 ). These trends are explained by the main climate modes of the Atlantic Ocean (NAO/EA during Winter, SAM during Summer) and are important for future research and long-term monitoring of the Senegalese Coast
Domaines
Sciences de l'environnementOrigine | Fichiers éditeurs autorisés sur une archive ouverte |
---|