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Entered as second-class matter March 1, 1920, at the Post Office at Easton, Pennsylvania, under the Act of August 24, 1912.

BULLETIN

OF THE

AMERICAN METEOROLOGICAL SOCIETY

Published Monthly by the American Meteorological Society
Publication office: 207 Church Street, Easton, Pa.

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The annual meeting of the Society will be held at 10 A.M., December 29, 1920, at the University of Chicago. The room will probably be one in Rosenwald Hall.

Election of Officers and Councilors.-The ballot inserted in the middle of this BULLETIN contains the names of the present officers (the ticket presented by the Council) and councilors, and the names of such other fellows who have received 20 or more nominations for any office. Instructions as to the mailing of the ballots are printed on the ballots themselves. They will be counted, along with the ballots cast in person, at the annual meeting.

Amendment to Constitution.-A proposed amendment to the Constitution is also printed on the ballots. It involves election procedure, and is intended to clarify certain difficult cases which may arise.

The Adoption of a Seal.—A seal designed by Lieut. C. N. Keyser, based somewhat on the designs of various seal designs submitted and on discussion with the other members of the Seal Committee, has been approved by the Seal Committee and is now submitted to the Society for adoption or rejection.

Policies of the Society and New Activities to be Undertaken.-The question, What shall we do about long-range forecasting investigations? is discussed by the Committee on Business Meteorology (on page 122-124). The question of, How are we to increase the amount of meteorological instruction in the United States to meet the present and coming demands for meteorologists? will be brought up by the Committee on Meteorological Instruction. A question of coördinate importance will also be raised: How can the Society best support the activities of the Weather Bureau? (see pages 128-134). These and other phases of the widening field of the Society's endeavors will also come up for discussion in the reports of the various committees.

PRELIMINARY PROGRAM OE THE CHICAGO MEETING.

Headquarters of the Society.-Congress Hotel, Michigan Boulevard and Congress Street (rates: one in room, without bath, $3-5, with bath, $4-9; two in room with bath, $7 and up). Those who have not yet made their reservations should do so immediately.

Place of Meeting.-University of Chicago, probably in Rosenwald Hall-consult final program of the American Association for the Advancement of Science, to be had at local Association headquarters.

TUESDAY, DECEMBER 28.

9.30 to 10.00 A.M.-Meeting of Council.

10.00 A.M. to 12.00 P.M.—Opening session for presentation of papers.

2.00 to 5.00 P.M.-Presentation of papers, especially those devoted to forecasting weather.

WEDNESDAY, DECMBER 29.

9.30 to 10.00 A.M.-Meeting of Council.

10.00 A.M. Annual meeting.

2.00 P.M.-Presidential address.

3.00 to 5.00 P.M.-Symposium on Physiological aspects of weather and climate.

THURSDAY, DECEMBER 30.

9.30 to 10.00 A.M.-Meeting of Council.

10.00 A.M. to 12.30 P.M.-Presentation of papers, possibly in joint meeting with the Association of American Geographers.

A more detailed program will be published in the December BULLETIN and the final program in the announcements of the A. A. A. S.

BUSINESS METEOROLOGY.

A. W. DOUGLAS, Chairman.

WHAT CAN BE DONE ABOUT LONG-RANGE FORECASTING? Business men have much to do with the future. They order their stocks of goods in accordance with the sales they expect to make, sometimes months hence. The manufacturer goes still farther ahead and tries to anticipate what quantities the merchants and retailers will call for. Thus, any forecasts that can be made of the factors likely to affect sales and orders become the basis for the manufacturers' and retailers' orders. In many lines of goods the general character of the weather has a definite and direct influence on sales, in others the effect is present but indirect; therefore, any predictions of the general character of the weather months in advance are of decided value to the business man. Without predictions the weather factor becomes guess-work.

Mr. Robert E. Horton, in a letter to the President and Secretary of the Society, proposing that a committee of the Society work on this subject, says:

"Such a committee, acting through the Society, could try out some things which official organizations probably would not care to undertake. I do not see why it should result in any discredit to the Society, or to the Weather Bureau, and it might be of great benefit to the public at large, as well as to the science of meteorology, if interest in advanced forecasting could be strongly stimulated to the extent that among other things commercial organizations would be willing to wager-for it would virtually amount to that-small sums of money on attempts to get results.

"It appears from some letters received that practical business men do not expect as much from advanced forecasts as from immediate forecasts that forecasts of this kind, if scientifically made, which are verified in only about 60 per cent. of the cases would be of decided value-those verified in 70 per cent. of the cases of great value-and if verification of forecasts a week or two ahead, even for some one factor, could be made which should be verified in 75 or 80 per cent. of the cases, the result would be of enormous commercial value. Of course forecasting is out of my line, and I am simply writing this as an intermediary between some of the correspondents in relation to corporation memberships and the officers of the Society, but I believe, however, that in almost any problem valuable side-lights may sometimes be obtained by general discussion between persons who know as little about the subject as most engineers, like myself, know about forecasting, and with that idea in mind, I am led t suggest that it might be advisable either at the next or at a special meeting of the Met'l. Society to make advanced commercial weather forecasting the subject for the meeting, advertising it so as to get the presence of men most interested and the views of as large a number of men as possible."

This proposal of Mr. Horton's has been favorably received by all who have given it consideration. The following comments were submitted by Charles F. Brooks:

"There is undoubtedly something to learn about monthly or seasonal weather sequences, e. g., the probabilities of months of various characters to be expected after months or seasons of particular kinds can be computed even if we do not know why weather sequences do not follow chance. We have the data, and it is merely a statistical proposition to find what we want. Mr. A. W. Douglas's forecasts for the hardware business and Dr. P. H. Dudley's winter character forecasts for the New York Central Lines (see BULLETIN, p. 67-68) are generally successful because they are based on the fact that in a general way previous sequences are likely to come again. These forecasts, however, even though based on a statistical foundation are not accompanied by statements of their mathematical probability of verification. The sooner we can state accurately the value of long-range forecasts as based on probabilities, the better it will be. Loose, enthusiastic talk based on scattered discoveries gives the subject a strong appeal, which may easily lead people far beyond the point justified by the actual possibilities of the purely statistical method.

"Another line of investigation, which holds forth great possibilities for forecasts of the seasonal character of the weather is that of the distribution and movements of ocean surface temperatures and the effects, in succession, on the temperature of the air over the oceans, the pressure distribution, and the winds not only over the oceans but also over the borders of the neighboring continents. In fact the pressure distribution in the Pacific is now recognized as a good indicator of the weather in the United States a week or more in advance, for the pressure systems that evolve (?) over the Pacific drift across the United States in their normal eastward course. Even the Atlantic pressure systems exert considerable influence on the weather of the eastern United States. (See Mo. Weather Rev., Nov. 1918, vol. 46, pp. 510–512)."

Professor R. DeC. Ward expressed his interest and wanted to be sure that if such activities were undertaken attempts would be made to make it clear that the Society was only investigating long-range forecasting and not actually making such forecasts.

Professor Charles F. Marvin's comments are as follows:

I think this discussion by Brooks and Ward regarding Mr. Horton's suggestion of a committee on long range weather forecasting is important, and the subject matter is one I have recently considered very seriously, with the result that an announcement will shortly be made of the extension of our forecast studies to include particularly the question of the cycles and the nature of the sequence of solar and terrestrial phenomena, with the view to extending the period of weather forecasts.

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I am a little doubtful that we are in a position to appoint a committee to concern itself with this problem at the present time, but I would like instead to suggest that the Council would welcome discussions of this question for publication in the BULLETIN, with the view to establishing a real scientific foundation for work of this character.

My idea is that comments or papers in the BULLETIN outlining what constitutes periodicities, cycles, systematic recurrences, etc., and how the laws of sequence if there be such may be stated in mathematical or definite form with known probable error, would be productive of worth while results.

It is my feeling that the conviction on the part of some students that certain cycles or periods exist is based on a study which has no other foundation than simply the law of chance. Perhaps it is difficult to make clear the exact idea, but I feel that the matter might be illuminated by a series of articles in the BULLETIN. This same fact prompted me to submit the note which has already been published in one of the early numbers, concerning temperature periodicities brought out by the studies of Brunt. This is a subject of deep interest but I think that the leaders in it should be particularly careful not to deceive themselves first and others afterward.

To indicate the present state of long-range weather forecasts made for business purposes, here is a statement just received from a large manufacturing and distributing concern:

WEATHER AND CROP FORECASTING IN MISSOURI, KANSAS, OKLAHOMA AND NEBRASKA. 1921.

With reference to long-range weather forecasting we have undertaken experiments covering various states in the corn and wheat belt. The nature of these experiments will be described here, particularly in connection with an area comprising portions of Kansas and Oklahoma.

It has been our purpose, as laymen rather than specially trained experts in the science of weather, to endeavor to find new ways of using available meteorological data, particularly rainfall, for practical business purposes-to interpret the facts as we have them, in terms of the possibilities for selling merchandise. Over a year ago we charted, month by month, the precipitation records of some 15 Weather Bureau stations and after careful study of the characteristics of each curve, made predictions as to their probable future courses. In other words, our forecasts dealt with the question whether a given month would have more rain or less rain next year than it did this year. In some cases, where extremes had occurred during the month, such forecasts could be made with success almost a certainty, and in numerous instances the advance information, general as it was, proved exceedingly useful.

Verification of over 150 predictions made in the manner described above shows that between 75 and 80 per cent. were correct, and over 90 per cent. correct enough for practical purposes. Less than 10 per cent. were in glaring contrast to what actually took place.

To apply this idea to a considerable area of country it is necessary to use records for a number of weather stations. Obviously it would be foolish to endeavor to predict for a whole state by using the data from only one point. Nor does the state average tell the whole story, as in many cases there are great local differences.

As an experiment we have taken a territory including most of southern Kansas and Central and Western Oklahoma, together with part of the Texas Panhandle, and forecast rainfall for the first eight months of 1921. We are beginning with

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six stations-Iola, Wichita and Dodge City, Kansas; Oklahoma City and Altus, Oklahoma; and Amarillo, Texas. Precipitation records have been charted for each, and monthly forecasts made, in the way already referred to.

of this appears below, just as it was sent out to those interested:

1921
January.

The summary

More precipitation at Wichita, Iola and Dodge City; less at Amarillo, Altus and Oklahoma City. A mixed forecast, according to which we should look for relatively more rain or snow in Kansas than in Oklahoma.

February.

At all six stations the probability is for more precipitation than in 1920.
According to the above, the mid-winter season-
—January and February-should
have more precipitation than last year.

March.

Wetter except at Wichita, Iola and Oklahoma City. In other words, relatively more rain or snow in the western than in the eastern part of the territory.

April.

All six stations indicate more rain in 1921 than in 1920.

May.

A mixed forecast-wetter at Wichita, Dodge City and Amarillo, drier elsewhere but nothing to indicate abnormally light rainfall.

June.

Another mixed forecast, but probably more rain everywhere except at Wichita and Amarillo.

July.

Drier everywhere except at Amarillo.

August.

Drier everywhere except at Dodge City.

The spring-March, April and May-should be if anything wetter than last year, chiefly because we can expect more rain in April, March and May perhaps will average an even break with 1920.

The summer-June, July and August-should be drier one than in 1920; while June should be wetter in most sections, both July and August ought to have less rain than in the present year.

With reference to crops, this means that we may expect a fairly good snow covering for winter wheat; more favorable moisture conditions in the early Spring than last season; more rain for winter wheat, but less rain for corn; possibly less propitious conditions for wheat harvest than in 1920.

With reference to business, in addition to the influence exerted by crop yield we may expect improved sales of such goods as snow shovels, sleds, and possibly skates and ice creepers-speaking from the standpoint of the distributer of general merchandise. An earlier Spring (that is, so far as earlier planting of crops contributes to the general attitude of the public) should mean a better and earlier movement of summer goods. A drier July and August should increase sales of such goods as garden hose, sprinklers and other dry weather goods. To supplement this forecast, as far as the outlook for crops is concerned. we made a study of the corn yield in Kansas and Oklahoma for a number of years. The Weather Bureau has demonstrated the exceedingly close relationship between the yield of corn and the amount of rainfall during parts of July and August. We have made charts showing yield per acre for the two states referred to, and examination shows that if the 1921 record is as high as that for 1920 it will be something most unusual. In other words, the charted "story" indicates that while the 1921 yield may be good it would be foolish to count on it. This is in line with what the rainfall charts show: together these two separate lines of investigation point to a reduced corn yield per acre next season.

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