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HONG KONG ANNUAL REPORT
to its meteorological duties, the Observatory operates a seismological station and a time service.
There was a slight decrease in the number of weather reports received from ships during the year; but the resump- tion of weather broadcasts from China partly compensated for this deficiency, and forecasting standards were main- tained.
The Royal Observatory's most important function is to give warning of storms. Whenever a tropical depression, storm or typhoon moves into the China Sea, 6-hourly and often 3-hourly statements of position, intensity and direc- tion of movement of the centre are issued. Frequent reliable ship reports and storm reconnaissances by aircraft help to locate storms accurately. When the Colony itself is threat- ened, the local storm warning system is brought into use, and warnings are widely distributed by means of visual signals, telephone, radio and Rediffusion. The local storm warning signal code was revised early in 1956 and a new strong monsoon signal defined.
Although typhoons caused considerable damage in the Philippines and on the coast of China during the year, Hong Kong was not seriously affected. The No. 1 advisory signal was hoisted five times when storms within four hundred miles constituted a possible threat to the Colony. The No. 3 signal followed on four of these occasions and was displayed for a total period of 114 hours, but gusts did not exceed 45 knots.
In the nine months following the introduction of the new signal code on 1st April, the strong monsoon signal was displayed during 370 hours.
METEOROLOGICAL RESEARCH
An experiment was commenced early in the year to deter- mine whether afforestation would affect the run off of surface. water in Tai Po Kau Forestry Reserve by increasing con-