Can precipitation over Israel be predicted from Eastern Mediterranean heat content?

摘要

Israel's location in a semi-arid region along the eastern coast of the Mediterranean Sea makes the prediction of winter precipitation socially and environmentally important. In 1982, Tzvetkov and Assaf proposed a connection between heat content (HC) in the Eastern Mediterranean (EM) in fall and precipitation over Israel in the following winter. We revisit their hypothesis using 21 years of remotely sensed sea surface temperature and sea surface height. The HC of the EM's upper layer is derived from these remotely sensed measurements under a reduced gravity approximation. Our results show a correlation of R = 0.6 between HC in the fall off the coastline of Lebanon and precipitation in Haifa, Tel-Aviv and Jerusalem. The depletion of HC during winter correlates moderately (R = 0.4) with precipitation in the three cities. Thus, according to our analysis, the upper layer HC in the EM in fall significantly impacts winter precipitation over Israel. Still, from a separate analysis, the atmospheric short-term condition seems to be important as well.