Recent Submissions

  • Manual of Marine Meteorological Observations, Tenth edition.

    U.S. Weather Bureau (Government Printing OfficeWashington, DC, 1959)
    The Conference of Brussels, called in 1853, was the first International Maritime Conference ever held. It sponsored the idea that governments should foster systematic weather observations on ships, and should prepare and publish charts of the prevailing winds, ocean currents, average sea and air temperatures, and tracks of dangerous storms based on the additional data. With the introduction of radio and fast ships, weather information became of vital importance to safe and efficient ship operation. Many countries began regularly scheduled weather forecasts to ships in nearby waters. Today, weather forecasts as well as charts are prepared from data collected through ship observations. Forecasts of weather and sea conditions arc prepared for ship operation, air-sea rescue missions, over-water air travel, military operations, etc. The need for accurate data is apparent, since the forecast cannot be any better than the basic observation. Organization of the Manual.-- This manual has been designed to serve primarily as a guide in the taking of weather observations at sea. It will be helpful in using the manual to keep in mind that the material in it has been organized to accord with the order of the various elements of the observation as they are entered in the basic Weather Bureau Form 615-5, "Ship's Weather Observations." Each major element of the observation is completely covered in a separate chapter. The first portion of each chapter is presented from the point of view of observing and evaluating the element without reference to its ultimate use; and the second portion, from the point of view of making a permanent record of it and preparing it for dissemination (coding).
  • Manual of Marine Meteorological Observations, Ninth edition, Change No. 1

    U.S. Weather Bureau (Government Printing OfficeWashington, DC, 1955)
    Change #1 to Circular M consists of the attached page changes; i.e., pages v-vi, 3-6, 27-30, 39-40, 47-54, 67-68 and 71-86. These changes are effective January 1, 1955, as indicated at the top o'£ each page in which changes were made. As a. further aid in identification, an asterisk has been placed in the left margin at the beginning of sections, paragraphs, lines, tables, etc., in which changes were made. In summary, the changes pertain to the fallowing: 1. Use of the symbol "X" in coding, wherever a. slant ( /) was used in the past. 2. Changes in Code Table 6, Symbol ww - Present Weather (mostly of a clarifying nature) 3. Changes in the definitions of code figures 0, 1 and 2 of Code Table 7, Symbol W - Past Weather. 4. Changes in the meaning of code figures in Code Table 15, Symbol a. - Barometer change characteristic in the last 3 hours. 5. Change in the meaning of Symbol Nh - See Par . 8320 and Code Table 3. 6. Change in the meaning of Symbol h - See Par . 8330 and Code Table 10. 7. Minor changes in the description of cloud categories for coding purposes and format changes in Code Tables 9, ll and 12, Symbols CL, CM and CH. 8. Minor changes in Ice Group Code Tables 20, 21 and 22 pertaining to Symbols K, Di and r. It is suggested that this page be initialed by the person inserting the attached pages and filed with the manual as a record that the change has been received and incorporated in the manual.
  • Manual of Marine Meteorological Observations, Ninth edition

    U.S. Weather Bureau (Government Printing OfficeWashington, DC, 1954)
    The Conference of Brussels, called in 1853, was the first International Maritime Conference ever held. It sponsored the idea that governments should foster systematic weather observations on ships, and should prepare and publish charts of the prevailing winds, ocean currents, average sea and air temperatures, and tracks of dangerous storms based on the additional data. With the introduction of radio and fast ships, weather information became of vital importance to safe and efficient ship operation. Many countries began regularly scheduled weather forecasts to ships in nearby waters. Today, weather forecasts as well as charts are prepared from data collected through ship observations. Forecasts of weather and sea conditions arc prepared for ship operation, air-sea rescue missions, over-water air travel, military operations, etc. The need for accurate data is apparent, since the forecast cannot be any better than the basic observation. . Organization of the Manual.--:This manual has been designed to serve primarily as a guide m the taking of weather observations at sea. It will be helpful in using the manual to keep in mind that the material in it has been organized to accord with the order of the various elements of the observation as they are entered in the basic Weather Bureau Form 1210F, "Log of Ship's Weather Observations." Each major element of the observation is completely covered in a separate chapter. The first portion of each chapter is presented from the point of view of observing and evaluating the clement without reference to its ultimate use; and the second portion, from the point of view of making a permanent record of it and preparing it for dissemination (coding). A complete index and a table of contents have been included. They should be consulted whenever there is any doubt about the location of instructions in the manual.
  • Manual of Marine Meteorological Observations, Eighth edition.

    U.S. Weather Bureau (Government Printing OfficeWashington, DC, 1950)
    The Conference of Brussels, called in 1853, was the first International Maritime Conference ever held. It sponsored the idea that Governments should foster systematic weather observations on ships, and should prepare and publish charts of the prevailing winds, ocean currents, average sea and air temperatures, and tracks of dangerous storms based on the additional data. With the introduction of radio and fast ships, weather information became of vital importance to safe and efficient ship operation. Many countries began regularly scheduled weather forecasts to ships in nearby waters. Today, weather forecasts as well as charts arc prepared from data collected through ship observations. Forecasts of weather and sea conditions arc prepared for ship operation, air-sea rescue missions, over-water air travel, military operations, etc. The need for accurate data is apparent, since the forecast cannot be any better than the basic observation. Organization of the Manual. - This manual has been designed to serve primarily as a guide in the taking of weather observations at sea. It will be helpful in using the manual to keep in mind that the material in it has been organized to accord with the order of the various elements of the observation as they arc entered in the basic Weather Bureau Form 1210F "Log of Ship's Weather Observations." Each major element of the observation is completely covered in a separate chapter. The first portion of each chapter is presented from the point of view of observing and evaluating the element without reference to its ultimate use; and the second portion from the point of view of making a permanent record of it and preparing it for dissemination (coding). A complete index and a table of contents have been included. They should be consulted whenever there is any doubt about the location of instructions in the manual.
  • Instructions to the Marine Meteorological Observers, 7th Edition.

    U.S. Weather Bureau (Government Printing OfficeWashington, DC, 1941)
    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 Caribbean 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 be 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. For these purposes the detailed entries of the mail report are of great value. It is a world-wide problem, hence mail reports are desired from every part of the oceans. While radio reports of the weather are required twice or even four times daily, the observations that are sent only by mail are required once each day at Greenwich mean noon, with appropriate notes in the Daily Journal as to conditions between observations.
  • Instructions to the Marine Meteorological Observers of the U. S. Weather Bureau, 6th edition

    U.S. Weather Bureau (Government Printing OfficeWashington, DC, 1938)
    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.
  • Instructions to the Marine Meteorological Observers of the U. S. Weather Bureau, 5th edition.

    U.S. Weather Bureau (Government Printing OfficeWashington, DC, 1929)
    The ocean meteorological program of the Weather Bureau calls in general for the making of but one regular observation a day, this, as well known, being made at noon· Greenwich mean time, (civil). However, in certain designated areas from which observations are transmitted by radiotelegraphy an additional regular observation is provided for at Greenwich midnight. Supplementing these regular observations are extra ones made under conditions of threatening or severe weather, gale and storm reports, and descriptive notes of weather experienced between observations, the lastnamed taking the form of a Daily Journal. The total requirements are such, however, as to make the smallest possible demands on observers consistent with the needs of the bureau in meeting its responsibilities for the ·issuance of forecasts and warnings, the procuring of data for publication on charts, and otherwise effectively carrying out its marine meteorological program. The provision that observations over the entire ocean should be made at the same moment of time is to make possible the construction of synoptic weather maps of large areas. While this object has been attained in part, nevertheless, owing to the varying observational requirements of different countries, the hope of a world synoptic weather map has never been completely realized. Generally speaking, in the Western Hemisphere where land observations are customarily made at 12 and 13 hours, Greenwich mean time, land and sea observations are in close agreement as to time; whereas in the Eastern Hemisphere agreement is at the present time almost wholly lacking. The value of simultaneous observations has received fresh recognition with the development of radio communication. The exchange of weather advices at sea and the growing practice among ships officers of constructing weather maps has had the effect of renewing interest in the entire subject. Concerted international action is now being taken to effectively organize the making of reports from ships at sea by radio to designated coastal centers of collection. It will be seen that by the daily receipt of ships' reports by radio an opportunity is afforded for the great national meteorological services to broadcast important advices to ships concerning daily weather conditions in their vicinity and along their course. There thus arises a reciprocal opportunity, as well as obligation, for ships to cooperate in this scheme of making observations of ocean conditions and reporting them by radio. Such cooperation will be coupled with the broadcasting and disseminating of useful advices and information by the national forecasters, made possible by observations from a large number of ships. Instructions for the transmission of observations by radio are contained in a separate publication, Radio Weather Code for Vessel Weather Observers. The material contained in these instructions has been restricted for the most part to information considered essential or helpful in observational work. For information on the general subject of meteorology observers are referred to the publications named in the bibliography on pages 63 to 66.
  • Instructions to the Marine Meteorological Observers of the U. S. Weather Bureau, 4th edition.

    U.S. Weather Bureau (Government Printing OfficeWashington, DC, 1925)
    The ocean meteorological program of the Weather Bureau calls in general for the making of but one regular observation a day, this, as well known, being made at noon G.M.T. (civil). However, in certain designated areas from which observations are transmitted by radiotelegraphy an additional regular observation is provided for at Greenwich midnight. Supplementing these regular observations are extra ones made under conditions of threatening or severe weather, gale and storm reports, and descriptive notes of weather experienced between observations, the last- named taking the form of a Daily Journal. The total requirements are such, however, as to make the smallest possible demands on observers consistent with the needs of the Bureau in me ting its responsibilities for the issuance of forecasts and warnings, the procuring of data for publication on charts, and otherwise effectively carrying out its marine meteorological program.
  • Instructions to the Marine Meteorological Observers of the U. S. Weather Bureau, 3rd edition.

    Heiskell, Henry L. (Government Printing OfficeWashington, DC, 1910)
    Introduction.- The Meteorological Report at present issued to vessels by the U. S. Weather Bureau, for forwarding observations , is a slight modification of that devised by the U. S. Signal Service for the purpose of its series of International Simultaneous Meteorological Observations, covering the period 1878-1887, which form in its turn superseded the once well-known Meteorological Journal. The last-mentioned form of record, which went into effect in 1876, and wh ch was in many respects identical with that recommended by the Maritime Conference held at Brussels in 1853, contemplated that the various meteorological observations should be entered at the end of every two hours throughout the twenty-f our, or a total of twelve sets of observations a day. The new form demanded, in place of this series, a single daily observation -this, however, to be taken over the entire se a at the same instant of time, viz, mean noon on the meridian of Greenwich, the object of the change being the utilization of a principal whose value, already recognized ashore, had meanwhile been shown to be equally applicable to meteorological observations at sea.
  • Instructions to the Marine Meteorological Observers of the U. S. Weather Bureau, 2nd edition.

    Heiskell, Henry L. (Government Printing OfficeWashington, DC, 1908)
    The form of Weather Report at present issued to vessels by the U. S. Weather Bureau is a slight modification of that devised by the U. S. Signal Service for the purpose of its series of International Simultaneous Meteorological Observations, covering the period 1878-1887, which form in its turn superseded the once well-known Meteorological Journal. The last-mentioned form of record, which went into effect in 1876, and which was in many respects identical with that recommended by the Maritime Conference held at Brussels in 1853, contemplated that the various meteorological observations should be entered at the end of every two hours throughout the twenty-four, or a total of twelve sets of observations a day. The new form demanded, in place of this series, a single daily observation- this, however, to be taken over the entire sea at the same instant of time, viz, mean noon on. the meridian of Greenwich, the object of the change being the utilization of a principle whose value, already recognized ashore, had meanwhile been shown to be equally applicable to meteorological observations at sea.
  • Instructions to the Marine Meteorological Observers of the U. S. Weather Bureau, 1st edition.

    Page, James (Government Printing OfficeWashington, DC, 1906)
    The form of weather Report at present issued to vessels by the U. S. weather Bureau is a slight modification of that devised by the U. S. Signal Service for the purpose of its series of International Simultaneous Meteorological Observations, covering the period 1878- 1887, which form in its turn superseded the once well-known Meteorological Journal. The last-mentioned form of record, which went into effect in 1876, and which was in many respects identical with that recommended by the Maritime Conference held at Brussels in 1853, contemplated that the various meteorological observations should be entered at the end of every two hours throughout the twenty-four, or a total of twelve sets of observations per day. The new form demanded, in place of this series, a single daily observation, this, however, to be taken over the entire sea at· the same absolute instant of time, viz, mean noon on the meridian of Greenwich, the object of the change being the utilization of a principle whose value, already recognized ashore, had meanwhile been shown to be equally applicable to meteorological observations at sea. The principle in question was the study of weather changes by means of daily synoptic weather charts, i.e., charts showing the conditions of pressure, temperature, wind, etc., existing at a given instant of time over a wide extent of territory. In the days of Maury, and for some years subsequent to the period of his greatest activity, the common aim of the various institutions engaged in the study of ocean meteorology was to obtain for each unit area of the sea's surface (generally a field bounded by the even 5° parallels and meridians, 5°, 10°, 15°, etc.) a reasonable number of observations of wind, weather, etc., extending over any period of years. The observations were then assembled by months, the average for each month taken, and the result stated as the normal condition for the month, i.e., the condition which the mariner might expect to find most frequently prevailing throughout the given field or square during the given month. Sailing routes were then laid down for the successive months in accordance with these normal conditions, and shipmasters were instructed to adhere to these routes as rigidly as the winds would permit, even when convinced by their own experience of weather changes, as well as by the indications of their meteorological instruments, that better results might be attained by adapting the course of the voyage to the conditions actually encountered. With the advent of weather forecasting as a science, using as a basis the daily synoptic weather charts, a new importance was attached to the sailor's meteorological observations. It was seen that in taking them he was not only adding to the stock of general knowledge of the climatology of the sea, the value of which to him was future and problematical, but also that he was putting himself in possession of certain special knowledge, the value of which might prove absolute and immediate. His last preceding observation revealed a certain existent condition of the meteorological elements, his present observation a more or less different condition. What did the changes which had taken place during the time intervening between the observations foretell? Did the existence of adverse winds in his immediate neighborhood imply better or worse conditions elsewhere 1 If better, would he not in this instance be justified in abandoning the route which had been laid down for him as the best under average circumstances, and seeking that which his present observations led him to believe would prove more favorable. A satisfactory answer to these various questions demands, in addition to a knowledge of the general periodic changes which occur in the several meteorologic elements from season to season, and from month to month, a knowledge of what may be termed the nonperiodic or accidental changes which occur from day to day; of the relation which· exists between the simultaneous changes in the several elements, and of the effect which a decided variation of pressure, temperature, or wind in any one neighborhood has upon the conditions existing in other parts of the ocean. To obtain this latter knowledge it is requisite that we have at hand for the purposes of study a series of charts or pictures, as it were, of the weather covering the entire ocean at a given instant of time, taken at regular intervals so brief that we may be confident that no marked change can occur without appearing, in its different stages, upon several of these pictures in succession. An examination of this series will then serve to reveal what changes have taken place in the interval separating any two of them; to trace the development and progress of any disturbance of the normal conditions that may have arisen; to compare the conditions of wind and weather prevailing simultaneously at points of the sea more or less remote from each other; to determine the constant relation, if any, which exists between these conditions; to make plain the manner in which a vessel, beset by foul winds, might have been navigated with the result that these winds would have been avoided, or even been replaced by fair; and finally, to instruct the navigator as to the conclusions to be drawn from his meteorological observations, in order that this result may be accomplished. It was with a view to combining these two equally essential methods of meteorological' investigation-the old, having for its aim the collection of a large number of observations, independent as to time, to serve as a basis for the study of the climatological changes as they occur from month to month, and the new, having for its aim the collection of a large number of daily simultaneous observations, to serve as a basis for the study of the weather changes as they actually occur from day to day-that the present form of weather report was adopted. It demands but a single observation per day, instead of the twelve demanded by the Meteorological Journal, this large reduction being made in the hope that the number of observers would increase in the same ratio as the services required of them would diminish, a hope which has proved more than justified. This single observation, however, is to be taken each day over the entire globe at the same instant of time, viz, Greenwich mean noon. The local or ship's time of the observation will thus vary with the longitude; on the meridian of Greenwich it will be local or ship's noon; in longitude 60° E. it will be 4 p. m.; in longitude 60° W. it will be 8 a. m.; in 120° E. it will be 8 p. m.; in 120° W. it will be 4 a. m. On the meridian 180° it will be midnight.