Although the research didn’t point to less rain as a result of climate change, scientific models estimate that the Eastern Mediterranean will see a 25 to 35 percent decrease in rainfall later this centurySend in e-mailSend in e-mail

Winter in Jerusalem
Winter in Jerusalem Credit: Emil Salman

Zafrir Rinat Feb. 13, 2021

Average yearly precipitation in Israel has remained almost static over the past decades, a survey of rainfall in the country over the last 90 years shows. However, the report, issued Thursday by the Israel Meteorological Service, points to several changes that have been taking place over the past decades, influenced by the global climate crisis.

At the end of the last rainy season (winter 2019-2020), researchers Noam Halfon and Yizhak Yosef calculated the average yearly precipitation for the past 30 years and then compared their findings with two earlier time periods and with the 90-year average. They concluded that there was no significant change in rainfall – only a 10-millimeter rise over the past three decades.

Dr. Baruch Ziv of Tel Aviv’s Open University, who last month presented the results of a similar survey he conducted for the Science Ministry for the years 1975-2017, found a 0.01 percent rise in precipitation over that time period, a statistically meaningless finding. “We didn’t see a trend of dehydration, which surprised us,” he said.

However, his research team identified a decrease in the number of rainy days per year, coupled with stronger rainfall. It also found that the rainy season has become shorter. In Israel’s center and north, the rainy season has shrunk to about three months, from December to February.

The Meteorological Service survey reached a similar conclusion, with a 10 percent decrease in the number of rainy days a year over the past three decades.

Even though for now the research doesn’t point to less rain as a result of climate change, scientific models estimate that by the middle or the end of the century, the Eastern Mediterranean will see a 25 to 35 percent decrease in precipitation. Extreme weather, like long drought or intense rains, are also expected.

Ziv mentioned that the Mediterranean Sea’s temperature has been rising relatively quickly, at 0.4 degrees Celsius (.72 degrees Fahrenheit) a decade. One of the results of this process is increased evaporation, which in turn leads to more intense rain clouds.

https://www.haaretz.com/israel-news/.premium-israel-has-fewer-rainy-days-a-year-but-it-s-not-getting-drier-for-now-1.9536612