Large‐amplitude pressure oscillations in the western Mediterranean

Pressure oscillations with unusually large amplitude of some 3 mb and periods of about 50 min have been registered in the Balearic Islands (western Mediterranean sea) during summer 1989. These large pressure oscillations are maintained over several hours and have been recorded on several occasions. The synoptic pattern and vertical structure of the atmosphere simultaneous with these oscillations is described. The large amplitude waves described here do not appear to be directly related to convective activity. Some of the characteristics of these waves are described, however, their source mechanism remains unclear.