In Israel, as elsewhere in the world, rapid technological development, improvement in standards of living and increased population density have brought in their wake pollutant emissions from both stationary and mobile sources. Israel’s specific conditionsconcentration of population and industry in the coastal area, small land area, variety of natural assets, and singular geological, topographical and climatic featuresaggravate the problems of air pollution.
Sources of Air Pollution
The main sources of air pollution are energy production, transportation and industry. Since these are largely concentrated in the coastal plain, the highest levels of pollution have been detected in this area.
Natural conditions for pollution dispersion in the atmosphere of the coastal area are not favorable. One of the most problematic air pollutants in Israel, as confirmed by air quality monitoring carried out since 1970, is sulfur dioxide (SO2). Until recently, relatively high concentrations of SO2, emitted for the most part by power plants and oil refineries, have been recorded in the Ashdod and Haifa Bay areas. Intense industrial activity in Haifa Bay, coupled with difficult atmospheric dispersion conditions caused by the influence of the Mediterranean sea and the complex topography of Mount Carmel, makes this area one of the most problematic in terms of air pollution.
The rapid emergence of industrial plants in the vicinity of urban centers has exacerbated air pollution problems throughout Israel. Pollution sources include cement plants, quarries, chemical and petrochemical plants and several other industries.
Dense vehicular traffic is also a major contributor to air pollution, causing high nitrogen oxides (NOx) concentrations, especially in the heavily populated urban centers of Tel Aviv, Jerusalem and Haifa. The problem is compounded by the operation of diesel-powered buses and trucks. Increased motorization has had a major impact on the deterioration of air quality, especially in the coastal area. The high amount of solar radiation in Israel has led to ever-increasing levels of photochemical air pollution.
Air Pollution Emissions
National estimates of air pollutant emissions play an essential role in air resources management, both nationally and internationally. Consequently, the Ministry of the Environment, in cooperation with the Central Bureau of Statistics, has prepared estimates on the countrywide quantities of air pollutants emitted into the atmosphere as a result of fuel combustion.
Energy production and consumption are major sources of air pollution in Israel. Israel’s energy economy is based on fossil fuels, especially oil and coal. In 1993, over 11.5 million tons of crude oil and 5.8 million tons of coal were imported into Israel.
Coal now supplies over 27% of the total energy requirement of the country
(97% for electricity generation and the rest for industry) and oil about 70%. Attention is currently being focused on the possibility of importing natural gas for electricity production, as a partial substitute for petroleum-based fuels in the future.
In 1993, liquified petroleum gas (LPG), used mainly for cooking and domestic heating, and natural gas for industry supplied some 2% of the total energy requirement. Gasoline, mostly for vehicles, constituted over 13% of the energy requirement; kerosene, supplied as jet fuel, and to a much smaller extent, for domestic space heating and cooking, constituted 6.5% of the total; light distillate fuel oil (equivalent to ASTM fuel oil No. 2), for diesel-powered vehicles, electric gas turbines and domestic and industrial heating was about 10.5% of the total. Heavy oil (equivalent to ASTM fuel oil No. 5 and 6) provided about 38% of Israel’s energy requirement (divided evenly between the electricity production sector and heavy industry).
In order to assess total emissions of combustion-derived pollutants, an emission inventory was prepared. The inventory was calculated using emission factors published by the U.S. Environmental Protection Agency. It is based on the annual consumption of hydrocarbon fuels and on the annual mileage covered by vehicles.
Findings indicate that with the exception of three pollutants sulfur oxides, total particulate matter and leademissions of all pollutants have increased drastically since 1980:
Carbon dioxide (CO2): In 1993, emissions (calculated as carbon) reached 11.4 million tons, an increase of 81% in comparison to 1980 levels.
Carbon monoxide (CO): In 1993, emissions reached 647 thousand tons, 128% more than the quantity emitted in 1980. The rise in carbon monoxide emissions is attributed to the dramatic increase in vehicle use.
Sulfur oxides (SOx): In 1993, emissions reached 273 thousand tons- -down from 308 thousand tons in 1980. The 11.4% decrease is due to the partial shift in electricity generation from high sulfur residual oil to low-sulfur coal in the early 1980s, and from the reduction in the average sulfur content of heavy residual oil from 3.5% to 2.5% in 1993. A further reduction to 2% was recently instituted.
Nitrogen oxides (NOx): Emissions have increased yearly and reached 190 thousand tons in 1993 as opposed to 79 thousand tons in 1980. This increase (141%) is attributed to the rising consumption of gasoline and diesel; the rise was partially offset by the decreased use of heavy residual oil and the switch to coal.
Hydrocarbons (HC): Emissions reached 82 thousand tons in 1993, as opposed to 34 thousand tons in 1980an increase of 141%.
Suspended particulate matter (SPM): In 1993, emissions stood at 26 thousand tons, just below the 1980 average (27 thousand tons). SPM emissions have slightly decreased (3.7%), since increased diesel fuel consumption by buses and trucks was offset by decreased consumption of heavy residual oil and the installation of high- efficiency electrostatic precipitators in Israel’s coal-powered stations.
Lead (Pb): In 1993, emissions reached 350 tons, compared to 432 tons in 1980. The 18.6% decrease is attributed to the reduction in the lead content in gasoline, from 0.42 grams per liter to 0.15 grams per liter.
Without doubt, the major challenge in coming years will be to significantly reduce pollution from vehicular sources. Despite a fourfold increase in the number of motor vehicles over the past two decades, little has been done to reduce emissions, either by legislation or by supervision and inspection.
Urban traffic constitutes an ever-growing menace to air quality in Israel. Vehicle density has risen from 34 cars per thousand in 1954 to over 230 in 1993. The number of cars in 1993 reached 1.37 million. It is estimated that by the year 2000 the number of cars in Israel will exceed 2 million.
Transportation sources are responsible for a lion’s share of the country’s carbon monoxide pollution and for a substantial percentage of the concentrations of lead, hydrocarbons, nitrogen oxides and particulates in the environment. With the exception of lead, the concentrations of all these pollutants have risen dramatically over the past decade.
Vehicle maintenance is checked once a year, during the annual registration test. Vehicular emissions are also tested on the roadside in accordance with standards set in the Abatement of Nuisances Regulations. Authorized examiners of the Ministry of Transport and the Ministry of the Environment, in coordination with the police, are empowered to conduct spot checks of vehicles, but both are short of staff and equipment. Only a very small percentage of vehicles are actually checked.
Several steps have already been instituted to help abate the problem; others are planned. All new cars imported into the country, beginning with 1995 models, must be equipped with catalytic converters; a gradual switch to unleaded gasoline is underway; and the lead content in regular gasoline has been reduced from 0.42 grams per liter in 1987 to 0.15% today (a complete phaseout of leaded gasoline within ten years is anticipated).
The Ministry of the Environment estimates that by the year 2000, some 50% of Israel’s motor vehicles will be equipped with catalytic converters and by 2025, all the vehicles will be so equipped. Since vehicles equipped with catalytic converter emit only a tenth of the pollution discharged from regular vehicles, the increased presence of these cars should bring about a real reduction in vehicular emissions. Furthermore, since such vehicles require lead-free gasoline, the consumption of unleaded gasoline should rise concomitantly. Until recently, only one type of unleaded gasoline was available in Israel95 octane. In order to further increase unleaded gasoline consumption, reduce the price of unleaded gasoline and promote sales, 91 octane gasoline is gradually being converted to unleaded gasoline throughout the country.
Emissions from diesel-powered vehicles (trucks, buses and taxis) are a particularly troublesome form of air pollution in urban areas. Since diesel vehicles emit respirable particulate matter (PM10) at a rate which is 100 times greater than the rate of particulates emitted from gasoline vehicles, the Ministry of the Environment opposes the trend of introducing private diesel cars to Israel. The ministry has called for an adequate and constant supply of lower sulfur diesel fuel (0.3% instead of 0.4%) as a first step while encouraging the Ministries of Energy and Transport to adopt tougher European standards on sulfur content, cetane number, viscosity and density. While the permitted sulfur concentration in diesel fuel for vehicles has been reduced to 0.3% in April 1994, the proposed adoption of the European directive should bring about a further reduction of sulfur to 0.2% and to 0.05% in the future. Efforts are also invested in ensuring that a proper infrastructure of garages exists in Israel to assure a high level of maintenance.
Electric cars could provide one solution for reducing automotive air pollution, especially in urban areas. Therefore, efforts are being invested in the introduction of electric vehicles in Israel. The Israel Electric Corporation, which operates an electric vehicle on an experimental basis, has initiated a study on the economic feasibility of such vehicles. It is estimated that the number of commercial cars and light trucks which can be switched to electric power may reach 5-15% of this vehicle fleet. The potential market for private electricity-powered vehicles is estimated at 15,000 vehicles. One possibility worthy of review is conversion of the urban bus fleet to electricity.
Other steps currently being undertaken or promoted include the promulgation of regulations on the prevention of vehicular emissions (both black smoke and carbon monoxide) which will enable the Ministry of the Environment and the police to better deal with the problem of emissions; increased roadside supervision and enforcement of vehicle emissions standards in accordance with European Union standards; restrictions on the use of private vehicles (particularly restricted entry into city centers); encouragement of public transport; information campaigns to increase public awareness; and promotion of research on the epidemiology of respirable suspended particles produced from diesel vehicles and sulfates.
High concentrations of nitrogen oxides (NOx) and ozone have been linked to respiratory disease, general health deterioration and adverse impact on agriculture and vegetation. In light of significant violations of the NOx standard in the Tel Aviv area, the Ministry of the Environment has placed the issue high on its list of priorities. Requirements for catalytic converters for all new vehicles will help reduce NOx emissions substantially. However, they are not effective against diesel-powered vehicles which are major sources of NOx pollution.
While the problem of NOx is severe on the local level, near roads or in busy urban centers such as Tel Aviv, the resultant problem of smog
(produced by a photochemical reaction of NOx with hydrocarbons and other elements) is more widespread. High concentrations of ozone (indicative of photochemical smog) have been found at distances of up to dozens of kilometers away from the source of emission. In the wake of these findings, a computerized model to project future photochemical air pollution levels was developed based on forecasts on the development of energy and transportation for the years 2000-2010. The results showed that concentrations which are double the standard may be expected by the year 2000.
In order to begin effective prevention, the scope and nature of the ozone problem must first be determined. Relatively few points of sampling for ozone exist, and no analysis of the problem has been conducted in Israel to date. To solve the problem, ozone and NOx-specific monitoring stations will be established, within the framework of the national air monitoring system, and an instrumented airplane will be used to survey ozone in the center of the country during the summer months for a three-year period. Additional activities currently on the drawing board include preparation of a photochemical dispersion model to help cope with smog episodes, ozone forecasting, and development of public awareness.
To slow down the rate of increase of NOx concentrations, several means must be undertaken, including adoption of new technologies for the prevention of NOx emissions, a switch to the use of natural gas, monitoring of all major sources, adoption and enforcement of strict emission standards and reduction of private vehicle use in city centers.