Instructions to the Marine Meteorological Observers of the U. S. Weather Bureau, 6th edition

Abstract

The ocean meteorological program of the Weather Bureau has two separate and distinct parts. First, there is the daily service by radio. Owing to the need for brevity, the radio reports contain a limited amount of essential information. The daily weather reports from ships and islands reveal the conditions over the ocean; when assembled on a map, including continental reports, they give a picture of weather conditions existing momentarily over a large region. A collection of observations is immediately returned to the mariner by radio broadcast so that he may draw his own weather map on shipboard. By this process, the weather at the earth's surface is mapped and much can be inferred as to conditions above the surface. Formation and movement of storms are revealed: advices and warnings of storms and forecasts of wind and weather are included in the broadcasts for the benefit of the mariner. For this first part of the Weather Bureau's program, observations are secured by radio from certain areas of the Pacific and Atlantic (including the Gulf of Mexico and the Carribean Sea). This service is of great value to agriculture and commerce as well as navigation; the daily weather forecasts for land areas depend to a considerable extent upon the ocean weather observations. To a very large degree ships' weather reports form the basis of warnings of the destructive storms that sometimes move from the ocean into coastal areas. As the second part of the program. the Weather Bureau uses more complete reports, forwarded by mail at the end of the voyage, in order that the weather of the oceans may he studied in greater detail. Results of these studies are the wind roses and weather data in other forms, as they appear on the pilot charts, also weather summaries for all parts of the oceans published for the information of the navigator. The life histories of important storms at sea are determined and recorded from ships' weather observations. Information regarding weather conditions at sea is furnished for use in admiralty cases. Observations are used in connection with land data for the construction of weather maps of world areas. Since the oceans influence the weather of the continents, the study of ocean temperatures is one of the important lines of work of the Bureau.