GEOGRAPHY AND CLIMATE
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restrictions on its use during dry seasons for some part of every year between 1934 and 1964. However, no such restrictions were necessary during 1965. A programme of reservoir construction has raised storage capacity to 15,858 million gallons and on 1st March 1965, Hong Kong began receiving water from the East River under a new agreement with China. Under this agreement, the Colony will receive 15,000 million gallons annually.
Hong Kong lies in the frost-free double cropping rice zone of East Asia. Market garden cropping, including the cultivation of cut-flowers for the urban and suburban markets, is becoming increasingly important. Vegetables are grown throughout the year, but most particularly during the cooler months which form the main vegetable season. During the last 10 years there has been a significant change in farming. The area of land under two-crop rice has decreased by about 60 per cent while intensive market gardening has increased approximately 34 times. The upland areas, which are predominantly grass covered and in several places severely eroded, tend to have highly leached acid soils. Land utilization of these areas is principally through afforestation, vigorously pursued since 1945.
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CLIMATE
Although Hong Kong lies within the tropics it enjoys a variety of weather from season to season unusual for tropical countries. The winter monsoon blows from the north or north-east and normally begins during September. It prevails from October until mid-March, but can persist until May. Early winter is the most pleasant time of the year when the weather is generally dry and sunny with temperatures about 21°C to 24°C. After the New Year there is often more cloud and although rainfall remains slight it is often fairly persistent. Coastal fog and drizzle occur from time to time in early spring-during breaks in the monsoon-when warm south-easterly winds may temporarily displace the cool north- easterlies.
The summer monsoon blows from the south or south-west and although it can occur from mid-April until September, it is not as persistent as the north-east monsoon of winter. Summer is the rainy season and is almost continuously hot and humid. The annual rainfall measured at the Royal Observatory has varied between