The climate of Surtsey

Abstract

The first meteorological measurement in Surtsey were conducted before the eruption ended in 1967 and since 2009 there have been continous automatic measurements on the island. Here we give the first comprehensive analysis of the climate of Surtsey, based on these observations, and compare it to the climate at the two other stations in the Vestmannaeyjar archipelago, Vestmannaeyjabær and Stórhöfði. Surtsey experiences a relatively mild but windy climate, with monthly mean temperature above freezing during all calendar months and wind speed exceeding 20 m/s on average 30 days a year. Precipitation measurements are challenging but show, as expected, the summer months to be the driest and October to be both on average the wettest month but also the most variable month. The measurements show the climate of Surtsey to be similar to the climate of the other two stations in the archipelago with the largest difference in wind speed, where Vestamannaeyjabær is sheltered while at Stórhöfði strong winds are enhanced by the orography.