2 INSTRUCTIONS TO MARINE METEOROLOGICAL OBSERVERS 



alities. Tliese (levelopnients have facilitated the preparation of 

 weather maps on shipboard and have l)een helpful to the mariner in 

 applying a foreknowledge of the weather to the problems of navi- 

 gation. 



It is inevitable that developments of this nature cause some in- 

 crease in the demands upon the mariner for weather observations, 

 both as to quantity and detail. However, it is the aim of the na- 

 tional weather services of the world to keep the mariner's meteoro- 

 logical work at a minimum consistent with the requirements of 

 navigation and general weather service and to return to him, in 

 publications and in weather broadcasts, a service that fully justifies 

 his cooperation. 



The ship's officer who avails himself of the radio weather broad- 

 casts, and constructs and studies weather maps as a regular feature 

 of his work, will find that the science of meteorology is not dull, but 

 on the contrary, full of interest. His meteorological work will cease 

 to be a routine duty ; his own observations will fit into the picture 

 that comes to him on the weather map ; the weather map Avill fit into 

 the momentary picture of the circulation of the earth's atmosphere 

 and its attendant phenomena. 



In order that the marine weather observer may make a beginning 

 in the serious study of meteorology, if indeed he has not already 

 done so, a description of methods of preparing weather maps is in- 

 cluded with these instructions, together with a list of publications 

 that will be helpful in decoding radio weather broadcasts, analyzing 

 the map, drawing inferences as to the weather of the future, and 

 gaining a more thorough knowledge of world meteorology. 



PART II. GENERAL INFORMATION FOR THE MARINE 



OBSERVER 



Arrangements for reporting. — Any master or officer will be wel- 

 comed as a weather reporter. He may write to the Weather Bureau 

 Office at Washington or he may visit, or write to, any of the port 

 offices of the Bureau in the list given on page 4. Forms, charts, 

 envelopes, and other material will be furnished to him. Thereafter, 

 he may secure additional forms, publications, and supplies by writ- 

 ing his request on the reports sent in, or he may call for them in 

 person. On visiting one of the port offices of the Bureau he is in- 

 vited to discuss any features of his meteorological work in which he 

 may need advice or assistance. 



When the shipmaster or one of the officers begins reporting tothe 

 Weather Bureau, immediate action is taken to secure a comparison 

 of the shi})'s barometer, which is used for records of atmospheric 

 pressure. The ]3roeedure necessary to insure accurate barometer 

 readings is described in the section beginning on page 9. 



No charge is made for any of the services rendered by the Bureau 

 to ships' officers in testing meteorological instruments or in supply- 

 ing forms, publications, and supplies. Franked envelopes are pro- 

 vided so that it will not be necessary to pay postage if the reports 

 are mailed in accordance with instructions contained in this manual. 



If the shipmaster wishes to send observations also by radio, he 

 should so state when visiting, or writing to, the Weather Bureau 



