Just as the British obsess about the weather, Israelis avidly monitor the level of the Sea of Galilee each winter — particularly after a string of consecutive drought years, broken only by last winter’s downpours, reduced the water mark to what was described as dangerously low.
Last year, the country rejoiced at reports that the lake was fuller than it had been since July 2004.
But that joy looks set to be short-lived, with meteorological forecasting a drier winter between now and the end of February that is more in line with the global warming and drying trends of recent years.
According to Prof. Yoav Yair, dean of the School of Sustainability at the Interdisciplinary Center, a Herzliya-based college, models produced by the Israel Meteorological Service and others suggest that the south of the country will be relatively hot and dry with the center and north enjoying average rainfall, at best. “In all likelihood it will not be as rainy as last year,” he said.
“The IMS checks the models in early November and then refers to the forecasts of the European Center for Medium Range Weather Forecasts,” he explained. “Then it makes predictions about December, January and February — the heart of the winter, which is usually the rainiest.”
He went on, “It’s quite clear that the south of the country will see dry weather, bordering on drought (defined as 80 percent of average rainfall), although the latter is too early to call. We’ll know that in January.
“As regards the center and north, the picture isn’t yet clear, with a higher probability of an average or a dry year, and a lower one of a rainy year.”
November’s weather has so far been average for the month, but October was the fourth hottest worldwide since measurements began, and the year 2020 is on track to be the second hottest globally, and the year with the most hurricanes, according to NASA and the National Oceanic and Atmospheric Administration.
The hottest year worldwide, 2016, was an El Nino year, during which the surface of the east-central equatorial Pacific Ocean warms. This causes relatively rainy years, although Israel saw its driest year in 90 years. “There isn’t one single, causal effect,” Yair said.
The current year, he continued, is an El Nina year, during which surface waters in that area of the Pacific Ocean cool. This usually kicks off a chain of events that brings drought to Israel.
“The trend is that the whole region is warming and drying,” Yair said. “We see it from Spain to Iraq – it’s all becoming drier and hotter and has been for 20 years. Last year was something of an anomaly, with the Sea of Galilee rising. It was out of the ordinary.”
In eastern Israel, daytime temperatures were the hottest ever, with other areas registering the second or third hottest temperatures since records began. Jerusalem saw its hottest October in 80 years.
October was also very dry, similar to just three previous Octobers since Israel’s establishment in 1948.
Indeed, the only rainfall occurred when a single cloud passed below the radar of the weather forecasters and over Jerusalem on October 20, causing a spectacular storm.
The only other Octobers that were as dry as this year’s occurred in 1948, 1964 and 1992.
Asked why several recent Israeli weather forecasts have missed the mark, Yair explained that IMS models were based on ten-kilometer (6.2-mile) grids. “A mistake of 10 kilometers can make the difference between sun and rain, wherever you live.”