The forecast in Israel: the rain will decrease and fall in a concentrated, heavy downpour that may cause floods

This is what Prof. Colin Price predicts, at a conference on global warming that will be held tomorrow in Tel Aviv. More in the forecast: snow in Jerusalem will be a rare event, the summer will be hotter with more heat waves

The expected global warming in the coming decades will bring about a change in the distribution of rain. In small Israel, this means: fewer rainy days per year, a decrease in the amount of rain every winter - and an increase in the number of extreme weather events such as severe heat waves in the summer.

It is already clear that the year 2006 will be no less hot, perhaps even hotter, than its predecessor (2005), which was crowned as "the hottest year the world has known in the 150 years of regular measurement of temperatures", and the last decade has been crowned as the hottest the world has known in the last thousand years.

This is evident from studies that have been done and are being done, among others at Tel Aviv University, and some of the findings will be reported by Prof. Colin Price, from the Department of Geophysics and Planetary Sciences in the Faculty of Exact Sciences, in his lecture at the scientific conference, under the title "Earth warming - is our future in danger?".
 The conference is organized by the Porter School of Environmental Studies at Tel Aviv University and the Association of Friends of the University. The winner of the Nobel Prize in Chemistry, Prof. Paul Krutzen from the Max Planck Institute in Germany, will be the main guest alongside renowned scientists and researchers from Israel and the world who will participate in the conference.
 The discussions will be held on Thursday, December 14, in the Britannia Building on the Tel Aviv University campus, in Ramat Aviv.
Prof. Yehuda Benyaho, head of the School of Environmental Studies, points out the place of the School of Environmental Studies, since its establishment in 2000, as the first and only academic center for multidisciplinary research and teaching on environmental issues in Israel. "Prof. Crutzen's visit as part of the conference will greatly contribute to strengthening and the central academic status of the school," added Prof. Benyahu.

Prof. Price's reference to the problem of rain sounds particularly topical in these days of "summer in the middle of winter" and the cessation of rains in Israel. "If we compare the predicted global warming to the human body temperature, the following picture will be obtained: when a person is healthy, his average temperature is 36.6-37 degrees. When his temperature rises by only one degree - he is said to be sick. When it rises two degrees - sometimes you end up in a hospital."

"The average temperature of the Earth is 15 degrees - after taking into account the heat measurements at the cold poles and the hottest areas, near the equator. In the last 100 years, researchers have noticed an increase of one degree in the average temperature of the world. The forecast speaks of another rise of one more degree, within the next 50 years - perhaps even a greater rise. An extreme forecast predicts even a warming of another 5 degrees, in the next 100 years, and not 2 degrees. This means: the earth will be completely different in the future than it is today. His condition is getting worse and worse."

According to Prof. Price, statistical models, computer simulations and studies that analyzed the data - all of which have one degree or another of uncertainty - present scenarios according to which as a result of the warming of the earth there will be a dramatic rise in the level of the seas and oceans, due to the melting of the glaciers and there will be many changes in weather events . All of these will have a direct and indirect ecological effect - on the flora and fauna, on human life.

"The change in the distribution of rainfall is perhaps the 'biggest blow' - also for us. Fewer rainy days means a decrease in the multi-year average amount. However, the rains will fall mainly in concentrated, 'heavy showers', which will cause floods, inundations and other damages - as part of the increase in extreme weather events. We have seen these phenomena in recent years in Italy, Spain and Greece, and they are on their way to us as well. The entire Mediterranean region, according to the various models, is already showing a growing tendency towards further drying. It will become more arid. Therefore, our summer will be hotter, there will be more heavy heat waves. If in Jerusalem, in the 50s, the temperature soared to a record of 35 degrees, for one day only, once every few years - today such a temperature is measured in Jerusalem several times every summer. Sometimes the temperature is also higher. The frequency of heat waves increases and increases. The Israeli winter may be warmer than before. There may be unusual, isolated and surprising events - about which they say 'the weather has gone crazy' - from drizzle to very light localized rain, not in quantity, only in the early morning hours - even in the middle of summer."

The change in the amount and distribution of rainfall in Israel may have a negative impact on the water reservoirs, the Sea of ​​Galilee and the aquifers (groundwater reservoirs). Prof. Price: "If the rains are stronger and fall in a shorter period of time - the reservoirs will not withstand the load and most of the water will be washed into the sea and lost. The state of our water system is deteriorating. Extreme events of very heavy rain pose a danger to property and human life. We saw this in April this year during the rain event in Wadi Ara."

And Prof. Price says: "If the winter is warmer, less snow will fall in Hermon - not to mention that in the distant future, it is possible that snow in Jerusalem may be very rare. Already today, we see a retreat in the snow, as a result of the rise in temperatures, in the various European countries."

The increased heat waves expected in the country, Prof. Price points out, will lead to an increase in the level and concentration of ozone in the air - a situation that is harmful to the health of children and adults. Another danger arising from the various models: the rise in sea level. Compared to the situation 100 years ago, an increase of about 20 cm - or 2 cm per decade - is already visible in the level. The forecast for the next hundred years speaks of an increase of up to 1 meter. We do not know today how much this will affect the coasts of Israel. The assumption: the increase will only be 20-30 cm in the coming decades, due to global warming, which will erode our coastline, will affect the ecology, possibly the water quality (the issue is now being investigated by Prof. Pinchas Alpert and Prof. Price of the Tel Aviv University and their colleagues in Germany) - but will not cause major flooding of the Israeli coastal cities. There will be places where special dams will have to be built to protect sensitive facilities.
The extremism in the weather - the clear manifestation of global warming - will cause an increase in the number of the most powerful hurricanes - very strong and destructive winds - compared to the 70s. This is the result of the increased evaporation of the ocean water and its warming - the energy that "fuels" the storms. "Fortunately, this problem will not concern us, but only on a global level."

Prof. Price will further emphasize in his lecture that the various computer models clearly show additional changes taking place in the last five years - compared to what happened 50 years ago: "Different regions on the globe, which used to be much colder and snowier - are now noticeably warming. Therefore, glaciers in Greenland and Siberia melted. In the Mediterranean region, between 2001 and 2005 there was an increase of half a degree in the average annual temperature, compared to the 80s. In Europe the situation is worse. If you compare these data to what was the case a thousand years ago, you can clearly see how much the industrialization that began in the world about 200 years ago - has brought about many impactful changes: since then the emission of greenhouse gases into the atmosphere - and their capture - due to the burning of fuels and the increased use of oil and coal - for engines. In the last 200 years, the amount of carbon dioxide in the atmosphere has increased by 30 percent, the amount of methane gas by 133 percent (due to agricultural use) and the amount of nitrogen dioxide by 19 percent (due to the use of fertilizers). Greenhouse gases cause global warming. Satellites have recently shown images of the dimensions of the melting glaciers. In the last five years there has been a decrease of 70 meters (!) in the thickness of the ice in Greenland. This has a significant effect on the climate changes that the world is going through now."

Prof. Price also points out that until the year 1800, the population of the earth was no more than 1 billion people. But within just 200 years, it has doubled itself more than 6 times, and within the next 50 years, according to UN forecasts, there will be over 11 billion people living in the world. Not only will they have a problem with food sources and water supply - they will also produce more gas emissions into the atmosphere (more cars, more air conditioners and other engines). The greatest rate of population increase is expected in Central Africa and India, not in Western countries, not even in China."

To summarize: "If the most moderate forecasts", Prof. Price emphasizes, "talk about an average increase of 2 degrees in the earth's temperature - their most serious meaning lies in the unexpected surprises that such a situation will cause. We are always worried about surprises - especially those that we don't know how close they are. If, for example, there is a large and sudden breaking of continental glaciers and their migration to the sea - a tremendous tsunami will break out and spread all over the world. There will be a sudden, sharp and rapid rise in the level of the seas and oceans, there will be floods and giant floods. Populated areas - will be abandoned. No one is able today to estimate what the dimensions of this great, destructive and deadly natural disaster will be.

"In huge areas, in the northern latitudes, in Russia and Canada, there is permafrost (permafrost) soil and under it huge reserves of frozen coal. If the temperature there rises above the threshold of 0 degrees - huge amounts of methane gas will be emitted into the atmosphere. In other words: the levels of greenhouse gases will rise even more - and with it will come another threatening warming of the earth."