The climate of Saudi Arabia varies from one province to another. The Kingdom lies in the tropics, and the nationwide average temperature is 18°C (64°F). Local average vary considerably from 24°C (75°F) in the Western Province, rising as we descend towards the southwest until it reaches 28°C (82°F) in Jeddah and 30°C (86°F) in Jizan. In the northwest, the average temperature is 22°C in Tabouk and 28°C in Madinah, which is 850 meters above the sea level. In the Asir region in the southwest, the average temperature is only 19°C because of the high altitude. The central province, which is surrounded by desert, has an average of 25°C for Riyadh, 21°C in Hai'l and 23°C in Qaseem. In Dhaharan, the eastern Province, the temperature is an average of 26°C. Apart from topographical factors, Saudi Arabia's climate is also affected by tropical winds which cause monsoons the west and southwest. These occur during the summer months. In the south, tropical continental winds blow particularly in winter often accompanied by sandstorms.
Saudi Arabia is one of the driest countries in the world, with rainfall averaging less than 5 inches per year. Marked seasons, in the European or American sense, do not exist. The climate is principally determined by the southerly shift in wind patterns during the winter months which brings rain and cool weather. Other factors such as latitude, proximity to the sea and altitude, also affect the climate. In the Empty Quarter, the great southeastern sand desert, ten years may pass with no rain. The Asir Highlands in the south receive rainfall due to the monsoon that may exceed 255mm (10 inches) per year. Jeddah, on the shores of the Red Sea, has a hot and humid climate year-round. Taif, on the other hand, and Abha, enjoy much more temperate weather.
Summer is hot with temperatures in some areas reaching 49°C (120°F). Winter is cooler with an average temperature of 23°C (74°F) in Jeddah and 14°C (58°F) in Riyadh. Winter temperatures drop below freezing in the central and northern parts of the country and snow and ice sometimes occur in the higher elevations in the south-west. In areas where there is little ground cover, a northwesterly wind blows for most of the summer months and may, especially in the eastern part of the country, whip up violent sandstorms. Between October and May is generally pleasant with cool nights and sunny days. Night temperatures in the coastal areas may dip into the 40s (Fahrenheit). From April to November, on the other hand, temperatures are considerably higher and life without air-conditioning would be very unpleasant indeed.
Before the discovery of oil, the economy was dependent upon the pilgrimage to Makkah and Medina and on the export of dates (pictured). Saudi Arabia is still one of the world's leading producers of dates but today the economy is dominated by oil. Petroleum revenues have been used to create an infrastructure, which will in time transform Saudi Arabia into a diversified industrial state. The Government, through the public sector, plays a major role in the Kingdom's industrial activity but, in recent years, the private sector has, with the Government's encouragement under the Kingdom's system of free enterprise, become increasingly involved in and responsible for industrial development and diversification.
Following the peak years of oil revenues in 1980/81 - 1982/83 (1400/01 - 1402/03 AH), it became necessary to undertake a very considerable downward adjustment to the government's level of expenditure. At the same time, the economy as a whole had to come to terms with more modest circumstances. The most remarkable feature of this process is the relative ease with which both the government and the private sector came to terms with the new circumstances. This is not to say that the process has not been difficult, demanding, even painful. But it is true that a decline in revenues which could have destabilized other economies has been taken as an opportunity to consolidate past achievements and to engender a more commercially realistic and efficient approach to all types of venture.
Oil and petroleum products account for more than 90% of the country's income. At Jubail on the Arabian Gulf and Yanbu on the Red Sea, major new industrial centres have been built. The power to run them is derived from natural gas from the oil fields. In addition to oil and petroleum products, the country produces iron and steel, processed foodstuffs, cement and electrical equipment. Domestic water requirements are met by desalination plants. Though natural water is in short supply, the government has funded agricultural development in order to reduce dependence upon imported foods and raise the standard of living in rural areas. There is also an expanding fishing industry.
The unit of currency is the Saudi Riyal (SR) which is divided into 100 halalahs. Notes are issued in denominations of 1, 5, 10, 50, 100 and 500 riyals. There are also one riyal coins. The riyal is quoted in US dollars but is based on Special Drawing Rights (SDR). As the SDR/Dollar rate varies, so the official Riyal/Dollar rate is revalued at intervals to keep within a narrow band of $1=SR3.75. There is no restriction on converting the riyal or transferring money outside the country. Most foreign currencies can be converted against the Saudi riyal. Commercial banks exist throughout the country and in addition, money-changers deal in foreign currencies and often offer banking transactions.