Final report of the Weather Bureau - M.I.T. Extended Forecasting Project for the fiscal year July 1, 1946 - July 1, 1947 / prepared by H.C. Willett ; and the staff of the M.I.T.-Weather Bureau Extended Forecasting Project.

Format:

Book

Author/Creator:

Willett, Hurd C. (Hurd Curtis), 1903-1992, author.

Contributor:

Mauchly, John W. (John William), 1907-1980, associated name, annotator, former owner.

Antonelli, Kathleen, associated name, former owner.

Massachusetts Institute of Technology. Department of Meteorology, issuing body.

Weather Bureau--M.I.T. Extended Forecasting Project, issuing body.

United States. Weather Bureau, issuing body.

Language:

English

Subjects (All):

Weather Bureau--M.I.T. Extended Forecasting Project.

Long-range weather forecasting.

Atmospheric circulation.

Physical Description:

[192] pages in various pagings (some unnumbered) : illustrations ; 28 cm

Place of Publication:

[Cambridge, Mass.] : Massachusetts Institute of Technology [Department of Meteorology], [1947]

Summary:

Introduction: This final report summarizes the results of the investigations which have been completed during the current fiscal year, and indicates the present status of the work which still is in progress. All indices and correlations computed during the year are listed, except that those computed during the. first half of the year and listed in the interim report dated February 1, 1947, are not re-listed in this report. Neither the organization, the supervision nor the personnel engaged in this project has changed in any detail from that described in the last interim report. Since the investigations which have been in progress under this project during the past fiscal year have varied greatly in character, it seems highly advisable by way of introduction to this report to indicate briefly how these different investigations are related to the primary objective of the project. The project is concerned primarily with the mechanics of the general circulation of the earth's atmosphere, and the attendant large-scale weather patterns, as a key to the problem of extended weather forecasting. The irregular fluctuations of the general circulation pattern. on whose correct prognosis all weather forecasting depends, may be represented synoptically either by the instantaneous flow pattern, or by the mean flow pattern averaged over a period of time. The instantaneous patterns, the usual weather maps, have been used always to represent the day to day fluctuations of the circulation and weather patterns for the preparation of daily weather forecasts. Mean flow patterns are best used to represent the prevailing state of the general circulation and the prevailing weather pattern over a period of time for the preparation of extended weather forecasts. The use of mean maps and the changes of the mean circulation pattern for extended weather prognosis is a technique that can be applied to time intervals of any desired length from 5 days or a week, through months, seasons, years, decades, centuries or geological epochs. When periods of a month or longer are used, it is advisable to express the circulation and weather patterns in terms of departures from a normal. When the longer term anomalies of the weather and circulation patterns are studied, there are two primary facts of interest to be noted. In the first place, the amplitude of the variations which occur does not decrease with increase of the time interval studied, as it should if our climate consisted of irregular chance fluctuations about a permanent normal. In fact, as far as can be judged from observational records, from historical evidence and from geological evidence, as the time interval is increased beyond a few years (perhaps 5) there is indicated a tendency for the amplitude of the anomaly fluctuations actually to increase. This fact suggests that the factors which control world climate are importantly variable over long periods ...

Notes:

"Prepared in accordance with the memorandum of understanding between The Weather Bureau and the Massachusetts Institute of Technology, dated July 1, 1946."

Local Notes:

Presented to the Penn Libraries by John W. Mauchly and Kay Mauchly in 1981 and 1986. Mauchly's annotations.

OCLC:

221015976