bluuebunny/crossref_metadata_2025 huggingface dataset:
Pressure and Temperature Variations over the Centers of Typical Migratory Anticyclones
Authors: Wasko Peter E.
Published: August 2018

From twenty years of January and February North American trajectories of migratory anticyclones four typical groups were found. Examples of these types were studied with respect to the temporal variations of the pressure and temperature at standard levels in a vertical column of the atmosphere over the centers of the migratory anticyclones. Certain characteristic features of these variations are summarized.
The Annual Course of Zonal Wind Speed at 700 Mb
Authors: Winston Jay S.
Published: August 2018

The annual course of zonal wind speed at 700 mb for latitudes 20° to 90 °N is portrayed in three ways—from monthly normal data, from monthly mean data averaged over a recent seven year period, and from 5-day mean data averaged over the same seven years. In a broad sense these representations have much in common, but the 5-day data reveal certain well-marked shorter period variations in the westerlies which appear to be related to singularities of the general circulation.
The Carbon Film Electric Hygrometer Element
Authors: Smith Walter J. , Hoeflich Nancy J.
Published: August 2018

A new type of electric hygrometer, the “carbon film element” is described. Its response to humidity changes is by electronic rather than electrolytic conduction. Main features of the new element are: high sensitivity to moisture changes, rapid response, absence of polarization effect, and a calibration independent of temperature between 0° and 40° C. Components of the carbon film, performance data, and manufacturing techniques are described.
Tentative Normal Diurnal Height-Change Charts of the 500-Millibar Surface Over the United States
Authors: Teweles Sidney
Published: August 2018

Charts are presented showing the smoothed mean monthly diurnal height change of the 500-mb surface during 1949–51 at U. S. Weather Bureau radiosonde stations. There are brief discussions of the influence of errors in temperature measurement on the 500-mb diurnal height change and of the relation between diurnal changes in surface pressure and 500-mb height.
Atmospheric Oscillations and Related Synoptic Patterns *
Authors: Donn William , Rommer Richard , Press Frank , Ewing Maurice
Published: August 2018

Records from sensitive microbarovariographs installed at Palisades, N. Y., Columbia University in New York City, U. S. Merchant Marine Academy, Kings Point, L. I. have been studied in connection with synoptic and local weather data. A number of interesting pressure events have been noted in connection with the passage of certain synoptic situations, These include pressure pump lines, squall lines, cold fronts and thunderstorms. Low level turbulence or convection associated with certain air masses at certain times is well-recorded by short-period pressure variations. Conclusions regarding the origin of squall lines are drawn from the empirical evidence given.
On the Transport of Atomic Debris in the Atmosphere
Authors: List R. J.
Published: August 2018

Collections of radioactive debris were made daily at 120 Weather Bureau stations throughout the United States during the atomic test series in Nevada in the Spring of 1952. The measuring techniques employed and the meteorological factors involved in the transport and deposition of debris are discussed. Several examples of the relation of computed meteorological trajectories to actual observations of debris are given.
A Proposal for a Revitalized Agricultural Meteorological Service *
Authors: Beall James M.
Published: August 2018

Agricultural Meteorology in the U. S. Weather Bureau from 1940 to date is discussed. Technical requirements for a well-rounded agricultural program in the Bureau are developed. This program envisions service on state level through cooperation with local Extension Service personnel, research and observations in collaboration with Experiment Stations and expanded forecast program with thrice weekly issuance of five-day forecasts, agro-climatic research using the facilities of the National Weather Records Center, development of instruments for measuring agro-meteorological parameters and the evaluation of effectiveness of weather control measures.
Non-frontal Crachin and the Cool Season Clouds of the China Seas
Authors: Ramage C. S.
Published: August 2018

The crachin of the coastal regions of south China and northern Indochina develops during the cool season whenever relatively moist air is cooled sufficiently by contact with the cold coastal waters to lower its condensation level below the level of turbulent mixing. Inter-mensal and diurnal variation of crachin are discussed as well as its coincidence with low-level winds veering with height. Forecasting procedures are listed. Over the China Seas beyond the crachin zone, convective cloud predominates, but as sea-air temperature differences steadily decrease through the latter part of the cool season, cloud amounts also diminish.
Time Constants of Radiosonde Thermistors
Authors: Sion Elio
Published: August 2018

Measurements of thermal time constants of radiosonde thermistors were made. Details of the experimental technique are presented whereby time constants were determined at various air speeds up to 2700 ft/min. Results are presented graphically to show the effect of time constant versus air speed with pressure and the corresponding average ambient temperature as encountered in the “average” atmosphere as parameters.
A Storm Analysis of the Tillamook Burn Cloud-Seeding Operation
Authors: Woodbridge David D.
Published: August 2018

A method of evaluating cloud-seeding operations is available in Oregon by the use of previously typed storm conditions. If cloud-seeding is effective in general, it must show similar departures under normal storm conditions. Thus previously typed storms are compared with similar storm types that passed through the Tillamook Burn area during the seeding operation of the summer of 1951.
Precipitation Echoes and Clouds
Authors: Ligda Myron G. H.
Published: August 2018

The size, shape and character of radar echoes caused by precipitation as viewed on PPI scopes are related to the clouds in which the precipitation develops. Photographs of PPI scopes showing precipitation echoes of various types are shown together with areal photographs of the clouds in the immediate vicinity of the precipitation. Such a presentation is an aid in the interpretation of radar precipitation echoes.
Clear-Air Turbulence Near the Jet-Stream Maxima *
Authors: Clem Leroy H.
Published: August 2018

The development of turbo-jet aircraft has made high-level clear air turbulence a major problem for aviation interests. This paper emphasizes the association of the majority of this turbulence with the pronounced vertical wind shear in and near the maximum wind speed centers that move along the jet stream.

A physical model is proposed as a possible explanation of clear air turbulence, the associated cirrus bands and wind streaks in the jet maxima. This model is supported by an analogy drawn with similar low-level phenomena studied by Woodcock and others. The model can explain distribution of these features in the horizontal by means of helical vortices which are dependent upon proper vertical wind shear and stability conditions. The observed multiple layers in the vertical are also explained by this model.

It is believed that the reason why most of the clear-air turbulence is found near the jet-stream maxima is simply because the necessary shear and stability conditions associated with this turbulence are most frequently fulfilled in that region.
Reconnaissance of the “Complete Hurricane” *
Authors: Sherman Leon , LaSeur Noel E.
Published: August 2018

There are various reasons, both practical and theoretical, which make desirable the location of the hyperbolic point as well as the “eye” of a hurricane. The practical difficulty in the location of the hyperbolic point which stems from its generally being in an extensive area of very light winds is easily overcome by the use of smoke bombs. Several flights made during August and September of 1954 demonstrate this.
A Case Study of the Jet Stream
Authors: Dickson Robert R.
Published: August 2018

Data, acquired by specially instrumented aircraft, are presented for two levels through a northwesterly jet stream. Wind shear on the cyclonic side of this jet stream is roughly twice that on the anticyclonic side. Stronger areas of clear air turbulence appear closely related to strong vertical wind shear. An area of uniform absolute vorticity exists for about 160 nautical miles north of the jet stream. Measured microvariations of the temperature along a pressure surface—up to 3.1 C° in 8.5 nautical miles—give indirect evidence of jet stream “fingers” of high velocity.
A Test of the Application of Vorticity Charts
Authors: Sanders Frederick , Kessler Edwin
Published: August 2018

A brief description is given of the preparation of charts depicting vorticity and space-mean flow patterns, in a manner similar to that proposed by Fjørtoft (1952). A comparison of the velocity of pronounced vorticity centers and the velocity of the wind over the centers indicated by the space-mean flow pattern is made from a series of daily charts for the autumn and early winter of 1953. It is found that the directions of motion of the centers and of the winds do not differ by more than ten degrees in slightly more than half the cases. A correlation coefficient of +0.69 is found between the speed of the centers and the speed of the winds. Use of the space-mean wind as a method of forecasting the displacement of the vorticity centers appears to be superior to the use of extrapolation. Application of the Rossby wave formula to all ridges and troughs in the space-mean flow patterns yields forecasts of the displacement of these features which are slightly better than extrapolation forecasts.
Estimating the Probability of a Future Event from Dichotomously Classified Predictors
Authors: Lund Iver A.
Published: August 2018

The familiar multiple-regression equations are adapted to the problem of determining the probability of a future event from dichotomously classified predictors. The probability of an event can be computed rapidly by this method and can be used as a first approximation of what the subsequent weather will be. An example is included to illustrate how the method is used and to show a comparison between the computed probability values and the observed values.
On the Efficiency of the Aitken Nuclei Counter
Authors: Ohta S.
Published: August 2018

Recently, a paper (2) has been published on the effect of time lapse between the processes of sampling and expansion in the Aitken counter. The conclusion was that a rapid decay of nuclei occurs in the counter. The cause of this decay was attributed to the gravitational effect upon the nuclei in the counter. Another effect, however, a diffusion of nuclei, was noticed by the present writer, and by this effect the decay of small nuclei was well explained.
Further Studies of Hurricane Structure by Aircraft Reconnaissance *
Authors: Simpson R. H. , Starrett L. G.
Published: August 2018

Research data and photographs obtained by aircraft reconnaissance in 1954 have clarified certain details of hurricane structure pertaining to the eye, the spiral rainbands, and circulation patterns.

A mound of stratocumulus clouds frequently present in the eye seems to be associated with the storm's circulation center. This “hub-cloud” in the presence of certain temperature distributions points to a level of non-divergence, usually below about 8000 feet, MSL.

Analyses of the rainband micro-structure reveal a tendency for a pressure minimum immediately adjacent to and on the high pressure side of the spiral bands. An explanation of this effect is proposed and the role it may play in the formation of parasite circulations or false eyes is suggested.

Finally, pictures taken from the airplane flying in the eye of the hurricane show cirrus clouds whose forms clearly establish the existence of a cyclonic indraft at very high levels over the eye.
A Note on the Effect of Aircraft Exhaust on Airport Visibility
Authors: Appleman H.
Published: August 2018

On several occasions reports have been received by Headquarters Air Weather Service of deteriorating weather conditions at an air base apparently caused by the landing of a number of jet aircraft. Such an occasion occurred at Goose Bay, Laborador in December, 1954. A detailed analysis has been made of this case and the probable cause of the phenomenon given.
Detection of Developing Tornadic Activity *
Authors: Dickson Edwin B.
Published: August 2018

Identification of developing severe weather activity as tornadic in nature may be possible, in many cases, by detection of rapidly recurrent sferics directional pips which occur as “long bursts.” Correlation of sferics storm locations from which these bursts were received with the subsequent development of tornadoes and funnel clouds is made.
A Weather Information Telemeter System
Authors: Myers R. F.
Published: August 2018

The design of a 90 channel data system which prints the digital values of temperature, precipitation, wind direction, wind velocity, dewpoint, and vertical temperature gradient directly on a teletype is described. Scheduled sequence, manual selection of individual stations or elements or continuous printing of a selected element from a selected station has been incorporated in the design.
Frequency Distributions of Predominant Tropopause Heights along 80 °W in Summer
Authors: Havens James M. , Baum Werner A.
Published: August 2018

Sample frequency distributions of height of the predominant tropopause in summer, at various latitudes along 80°W, as interpolated from analyzed tropopause-contour charts, are studied. At most locations the frequency distributions are such as to be statistically acceptable as being samples drawn from relatively simple theoretical parent distributions. It is therefore possible to compute theoretical frequencies of predominant-tropopause height for individual class intervals of height at these locations.
Luminous Reflectance (Visual Albedo) of Natural Objects
Authors: Penndorf Rudolf
Published: August 2018

The spectral reflectance of natural objects is taken from Krinov's measurements. Based on these data, the luminous reflectance (visual albedo) is computed for natural objects. The results obtained are compared with other published data. The wealth of data can now be grouped into four classes and twenty-four main types. The luminous reflectance of most natural objects (except snow and a few rock formations) remains below 15 percent.
Temperature Inversion as a Factor in Formation of Tornadoes
Authors: Ward Neil B.
Published: August 2018

Experimental results are shown which indicate that one of the factors which differentiates between ordinary thunderstorm convectivity and tornado activity may be the formation or intensification of a restricting layer such as a temperature inversion. Evidence is presented to show that such a layer, penetrated by a convective column, can bring about horizontal convergence beneath the layer into an area sufficiently small that, if some rotary motion is present, a funnel is produced. Indications are that the diameter of the opening through which the converging air exhausts has an important effect on the formation, type and intensity of the funnel. Further, it is shown that the formation or intensification of a temperature inversion may restrict the diameter of an existing convective column in a manner similar to the experimental device.
Multiple Correlations of Particulate Air Pollution with Weather Factors at Detroit and Windsor *
Authors: Baynton H. W.
Published: August 2018

For a six week period in 1952, a network of twenty high volume air samplers was used to measure the concentration of particulate pollution in Detroit and Windsor. Using a graphical multiple regression technique, regression curves are obtained which relate particulate pollution directly with temperature anomaly, and 24 hour temperature change, and inversely with wind speed, and duration of precipitation.

The relationships were modified for application to independent data covering each of the four seasons. The results appeared useful, although rigorous claims about significance cannot be made where graphical methods are employed.
Wind Aid From Wind Roses
Authors: Crutcher Harold Lee
Published: August 2018

Wind distributions are investigated with a view toward designing some easily applied methods to provide reliable estimates of wind aid or equivalent winds for airborne craft. The Contingency and the Standard Vector Deviation Wind Roses are used.

Wind data at Nashville, Tennessee, at the 300 millibar pressure level and during the winter season are utilized to demonstrate the use of graphical methods. The Wind Aid values obtained graphically from the Nashville data are found to be acceptable as estimates of the computed values. In addition, data at other points are tested. The results corroborate the Nashville study.

Graphical procedures which employ the Contingency or the Standard Vector Deviation Wind Roses, therefore, do provide easily applied methods for providing reliable estimates of wind aid for aircraft.
An Approximate Relation between the Variability of Wind and the Variability of Pressure or Height in the Atmosphere
Authors: Buell C. E.
Published: August 2018

The square of the standard deviation of the height (p = constant) or of the pressure (h = constant) and the square of the (vector) standard deviation of the wind are found to be approximately linearly related over large areas and through a deep layer extending well into the lower stratosphere. As a result, some statistical characteristics of the large scale motions of the atmosphere depart markedly from those expected on the basis of turbulence theory. An explanation of the empirical relation between the (vector) standard deviation of the wind and the density of the air is offered.
Weather and the Production of Burley Tobacco
Authors: Beall James M.
Published: August 2018

Tobacco is an economically important crop in the United States. It is grown under a variety of climatic conditions each imposing its particular microclimatological and micrometeorological effects. The curing of burley tobacco depends particularly on the proper control of relative humidity. A humidity forecasting project started in 1954 in Kentucky by the Weather Bureau with the cooperation of the University of Kentucky has resulted in that some farmers using the service have received up to 7 cents a pound more than parity for their tobacco. Consequently the Weather Bureau has decided that the service is well worth while.
Atmospheric Studies from a Moving Weather Observatory
Authors: Schaefer Vincent J.
Published: August 2018

An exploration of the diurnal variations in the microclimate of a forested mountain in northern Idaho was made during a 36 hour period toward the end of a prolonged period of cloudless weather. Measurements were made from the mobile weather observatory developed jointly by the University of Washington, U. S. Forest Service and the Munitalp Foundation. A 4 meter mast mounted so it rode six feet ahead of the vehicle contained sensing elements at the ½, 2 and 3½ meter positions. Temperature and dew point were recorded on an eight channel recorder which completed its cycle every 32 seconds. Exploratory runs were made during which the observatory stopped at each 500 foot gain in altitude and at several additional stations in between. A study of the data showed, however, that the response time of the aspirated temperature and dew point sensing elements was so rapid that pauses were not necessary if the vehicle moved in the speed range of 6 to 10 mph.

Large differences were noted between day and night and north and south slopes. The so-called “thermal belt” was sharply defined and the drainage winds, stable and unstable air regions and the movement of moisture from the upper slopes into the valleys by drainage winds down the stream valley were nicely indicated by this dynamic study.
Refractive Index Profiles and Associated Synoptic Patterns
Authors: Arvola William A.
Published: August 2018

A study is made of meteorological conditions associated with synoptic patterns passing over the Middle West leading to super-refractive index profiles. The signal strength for a 71.75 mc TV-link in Illinois is related to the refractive index profiles.
Synoptic Models of Thickness and Isotherms
Authors: Kochanski Adam
Published: August 2018

Models of daily thickness patterns were developed for the layers 500–300 mb, 300–200 mb and 200–100 mb. Isotherm models are also given for the 300-, 200-, and 100-mb levels. The models apply to an idealized wave-pattern and show the substantial difference between conditions over contour troughs and those over contour ridges. Tropospheric-type patterns (cold troughs, warm ridges) are predominant in the 500–300-mb layer while stratospheric patterns (warm troughs, cold ridges) prevail in the 200–100-mb layer. The 300–200-mb layer shows a mixed tropospheric and stratospheric type. The presented models are only tentative as limited data were available for their construction. The use of models in analysis and forecasting is discussed.
A Note on the Climatic Variation of Absolute Humidity
Authors: Bean B. R. , Cahoon B. A.
Published: August 2018

Maps of the variation of absolute humidity over the United States are presented for the values exceeded 1, 50 and 99 percent of the time during the months of February and August. Cumulative distributions of absolute humidity are presented for nine climatically diverse locations for the four seasons of the year. In addition, regression equations have been derived to enable one to estimate the values of absolute humidity exceeded 1 and 99 percent of the time at any location for which average values are available.
A Practical Way to Make Air Mass Thunderstorm Forecasting Easier and More Reliable
Authors: Telfer Ray T.
Published: August 2018

This study introduces a plastic device for mechanically progging soundings rapidly. It also shows how this device can be used with the Bailey local thunderstorm forecasting graph to make local thunderstorm forecasting easy and more reliable.
A Study of Mesosystems and Their Radar Echoes 1
Authors: Fujita Tetsuya , Brown Henry A .
Published: August 2018

Five mesosystems, occurring on 4 to 5 June 1953 in an area 500 by 600 mi near Chicago, were analysed with the use of data from regular synoptic stations. Four of the systems were of the well known type having a pressure-surge line, a thunderstorm high, and a wake depression. The fifth system, a trough 500 mi in length, traveled at the rate of 60 kn.

By using radar pictures taken every minute, the movement of echoes was also studied. The echo velocities, which were approximately 20 kn while a pressure-surge line was 100 mi distant, increased up to 40 kn with the approach of the line. The individual echoes in the line moved in an east-northeast direction while the pressure-surge line, oriented southwest to northeast, proceeded towards the south-southeast. The centers of the mesosystems moved in the same direction as the individual echoes in the squall line.

Hourly precipitation amounts accompanying each system were integrated with respect to time and “time integrated” precipitation charts were then constructed.
On the Behavior Patterns of Cyclones and Anticyclones as Related to Zonal Index
Authors: Bradbury Dorothy L.
Published: August 2018

A statistical study of the variations in the frequency patterns of cyclone and anticyclone centers with respect to the zonal index is described. The results indicate significant variations, especially over the oceans, in the ratio of the frequency of cyclone and anticyclone centers during high-index months to the frequency during low-index months.
Observations of Small-Scale Rainfall-Rate Time Variations with Sensitive Rainfall Recording Instruments
Authors: Gerhardt John R.
Published: August 2018

A research program involving the study of the attenuation and backscattering by rain of millimeter wavelength radiation has resulted in the requirement for very accurate measurements of rainfall characteristics along paths ranging from 1000 to 2000 ft. A special continuous-wire raingage has been developed which gives an essentially continuous rainfall response by measuring the water level in a cylindrical gage. An accuracy of 0.001 in of rain is obtainable. The responses from two of these gages are compared with those from a number of modified tipping bucket and other gages for several rains in the Austin area.
Engineering Meteorology: Wind Effects on Motor Vehicle Stability1
Authors: Benner William
Published: August 2018

The primary conditions under which the single meteorological parameter of wind will make its presence known against a motor vehicle are considered. The standard engineering techniques for reducing the undesirable effects on the car are discussed. These factors result in problems of measuring the wind aspects which are involved and pose the difficulty of locating adequate test facilities.
Engineering Meteorology: The Effects of Weather and Climate on Concrete Pavement1
Authors: Brock Fred V.
Published: August 2018

Concrete pavement may be adversely affected by weather and climate through the freezing process either within or under the pavement. The common results of freezing action that are detrimental to the durability and usefulness of the pavement are differential frost heave, loss of subsoil bearing strength, migration of subsoil, loss of strength of the concrete itself, and scaling of the pavement surface. Temperature and moisture are the dominant factors in each of these effects.
A Method for the Construction of Climatological Fallout-dose Patterns
Authors: McCabe Major John T. , Potter Thomas D.
Published: August 2018

A simple method of finding the percentage frequency that areas near a target will be affected by radioactive fallout of a critical dose is presented. The target location, the climatological period, the fission yield, and a critical dose or dose rate must be specified. If the distribution of the actual effective winds is not available, the assumption of a circular normal distribution of the effective wind is made. This distribution can be obtained by C. E. P. Brooks' method or, if the points are numerous as in describing an areal frequency pattern, by a mechanical method described herein.
The Application of High-Speed Computers in Irrigation Research
Authors: Engelbrecht Howard H.
Published: August 2018

An IBM–650 program has been developed for the basic purpose of evaluating and comparing Thornthwaite and Penman potential evapotranspiration values and various methods for soil-moisture accounting. To the extent that the existing potential evapotranspiration formulas and soil-moisture accounting procedures are acceptable, the IBM–650 program supplies basic data for drought probabilities or irrigation-water probability studies.
On a Criterion of Representativeness of Sea-Surface Temperature Data1, 2
Authors: Schell Irving I.
Published: August 2018

Three pairs of historical series of mean monthly sea-surface temperatures in the North Atlantic were analyzed, one pair from the tropical area, 15N to 20N, 60W to 65W, dominated by the North Equatorial Current; the second from the semitropical area, 30N to 35N, 55W to 60W, by the Gulf Stream; and the third pair from the polar area, 45N to 50N, 45W to 50W, off Newfoundland by the Labrador Current.

The results obtained show that, by successively eliminating those values based upon few observations per month, the standard deviation, σ, tends to become relatively constant and may then serve as a criterion of the representativeness of sea surface temperature data.
The Falling Rate Phase of Evaporative Soil-Moisture Loss—A Critical Evaluation
Authors: Lowry William P.
Published: August 2018

This paper presents an abbreviated review of the literature concerning the relationship of evaporative moisture-loss rate to soil-moisture content. Results from a variety of sources appear to fall into four major types of curve expressing this relationship. The author compares these types and concludes that three of them are mutually supporting and represent special cases of the same process. The fourth type is considered contradictory. It is concluded further that the search for a neat, concise, general statement of the relationship under consideration is probably futile.
A Record Rainfall at Okinawa
Authors: Jordan C. L. , Shiroma Michio
Published: August 2018

A maximum rainfall of 38 in. was recorded during an 18-hr period as a typhoon passed over the island of Okinawa in September 1956. The observed weather conditions during the typhoon passage are discussed in relationship to the observed rainfall distribution on the island and some comments are offered on the problems of evaluating the reliability of measurements of very heavy rainfall.
Safety Deflation Device for Large Captive Balloons
Authors: Daniels Glenn E.
Published: August 2018

A mechanism for the automatic deflation of captive balloons in the event of mooring cable breakage has reduced a hazard to air navigation. Devised at the U. S. Army Electronic Proving Ground (USAEPG) at Fort Huachuca, Arizona, this mechanism has also effected savings in recovered balloons and meteorological instruments.
A Brief Survey of the Meteorological Aspects of Atmospheric Pollution
Authors: Cramer H. E.
Published: August 2018

This article is intended to provide a brief survey of current knowledge of the meteorological aspects of air pollution for meteorologists and others who are not specialists in diffusion. Improved understanding of atmospheric dispersal processes has largely occurred in proportion to the amount of satisfactory empirical data available. The most comprehensive observations refer to small-scale processes, but considerable information on large-scale processes has been obtained in studies of radioactive fallout; comparable data for intermediate-scale processes of the type involved in community air pollution appear to be lacking. Although a satisfactory diffusion theory has not yet emerged, the outlook is encouraging.
Engineering Meteorology: The Weathering of Exposed Surfaces by Atmospheric Pollution 1
Authors: Munn R. E.
Published: August 2018

The topic is approached from the viewpoint of community air-pollution programs and control. After a brief discussion of the economic costs of atmospheric pollution in an industrial area, a skeleton outline of the important factors in weathering by pollutants is presented. A few of the factors are considered in detail under the general headings of soiling, erosion, and corrosion.

Significant differences in weathering are found for industrial, rural, marine, and very dry climates. Most community surveys include routine tests of the dirtiness of the air but exclude corrosion tests, although this factor is of great economic importance.

Methods of corrosion testing are considered, and it is concluded that they are not feasible yet for community surveys. Increasing interest in corrosion, however, is undoubtedly leading to a broader understanding of the problem.
Whiteout—A Bibliographical Survey
Authors: Harker George S.
Published: August 2018

The polar phenomenon of whiteout is described through the medium of quotations from persons who have experienced the phenomenon. The meteorological conditions indicated to produce the phenomenon are noted and the mechanism of their operation discussed in terms of research findings available in the literature. Topics considered are: diffuse illumination, meteorological range, and illumination levels. Contributory physiological factors are noted and discussed under the following headings: retinal illumination, empty-field myopia, and entoptic phenomena. The psychological import of whiteout is discussed in relation to perception of the vertical, directional orientation, and distance estimation.
Reservoirs to Match our Climatic Fluctuations 1
Authors: Thomas H. E.
Published: August 2018

Alternating wet and dry periods, each of several years' duration, are suggested by the records of precipitation at several localities in the southwestern United States, and they are indicated also by the records of natural streamflow. In some regions, the precipitation and runoff since 1930 have been at a significantly lesser rate than in the quarter-century prior to 1930, and in most of the Southwest drought has been prevalent since about 1945. A large proportion of the precipitation stations and stream-gaging stations in the Southwest have been established subsequent to 1930, and records from them are likely to be too short to indicate the climatic norm.

Reservoirs, both surface and subsurface, can smooth out the marked daily, seasonal, and annual variations in water supply from precipitation, and can furnish water at rates more nearly in accordance with human needs. Many ground-water reservoirs, and some surface reservoirs, after being well filled during years of abundant precipitation and runoff, have provided an adequate supply of water during several successive years of drought. In the protracted drought periods that have been recorded in the Southwest, however, storage in most reservoirs has been depleted seriously, and the actual yield of some of them has been significantly less than the computed long-term average yield. Maintenance of a relatively constant yield throughout protracted wet and dry periods would require reservoirs having large storage capacity and losing as little water as possible by evaporation or other natural discharge; accurate evaluation of the long-term average inflow is a prerequisite to successful utilization of the reservoirs.
The Infrared Hygrometer as a Potential Meteorological Aid
Authors: Wood Rex C.
Published: August 2018

The infrared absorption-spectra hygrometer possesses inherent advantages which will be of interest to the meteorologist concerned with difficult humidity-measurement problems. Data samples are presented which illustrate typical atmospheric humidity variations as obtained with a relatively uncomplicated experimental instrument featuring a short, 12-in sensing path. Also included is a discussion outlining method advantages in particular areas: micrometeorology, air weather reconnaissance, arctic meteorology, and other research applications.
Radar-Echo Enhancement at Frontal Boundaries by Refractive Index Inhomogeneities
Authors: Schuetz John
Published: August 2018

Observations associated with some unusual radar echo lines are presented. Analysis of raingage and radar data indicates that echo enhancement due to a steep refractive index gradient is occurring. Acceleration of the front may play an important role in forming this echo. Synoptic application of observations of these unusual echo lines is discussed.
Air Masses in Central America
Authors: Portig Wilfried H.
Published: August 2018

The existence and qualities of air masses in Central America are pointed out and explained by the geographic singularities of the North American continent.
The World's Strongest Winds as Revealed by Tateno Relay-Method Soundings
Authors: Arakawa H.
Published: August 2018

Upper winds over Japan during the winter are known to be stronger than at any other place in the world. Here, analysis for the Tateno relay-method soundings over three winters is presented. Frequency of maximum wind speed in 1000-m intervals of height and in 10-m-per-sec intervals of speed and directional distribution of maximum wind speed are given. Strong vertical wind-shear data observed are also studied.
An Instance of Reported Winds of 200 Knots in the Lower Troposphere1
Authors: Jordan C. L.
Published: August 2018

Rawin observations made at Kindley AFB, Bermuda on 28 March 1955 reported unusually strong winds in the lower troposphere at two successive observation times. A maximum reported speed of 222 kn was shown at 9000 ft at the top of a strong frontal inversion. The credibility of these observations is examined along with aspects of the general problem of evaluating cases of extremely strong rawin reports.
The Distribution and Variability of Cold-Front Precipitation1
Authors: Cox Myron K.
Published: August 2018

Radar data are used to investigate wintertime cold-front precipitation patterns in the vicinity of Cambridge, Massachusetts. No significant correlation was found to exist between the extent of precipitation as indicated by radar-scope coverage and selected synoptic parameters—with the exception of the Instability Index which proved to be significant at the 5 per cent level. Further comparison is made between the average precipitation amounts as indicated by the climatological network of rain gauges and the same synoptic parameters. Again, a significant correlation was found to exist only for the Instability Index.
The Tornado in Western Canada 1
Authors: McKay G. A. , Lowe A. B.
Published: August 2018

Little information is available on Canadian tornadoes although from time to time these severe local storms take a serious toll of life and property.

A climatology of tornadoes on the Canadian prairies is presented. These storms are most frequent in that area near the junction of the Saskatchewan-Manitoba-North Dakota borders. Compared to American tornadoes, they reach a maximum frequency both later in the day and in the season. A higher percentage move from northwest than is observed in the United States.
Estimation of Surface Wind Speeds in Tropical Cyclones
Authors: Jordan C. L. , Fortner Limon E.
Published: August 2018

The surface wind-speed reports in tropical cyclones given by aircraft-reconnaissance observers are based almost exclusively on state-of-sea observations. The reliability of wind estimates prepared in this manner is considered along with some of the practical difficulties involved in making observations from reconnaissance aircraft.
Principal Frontal Zones of the Northern Hemisphere in Winter and Summer 1, 2
Authors: Reed Richard J.
Published: August 2018

Daily synoptic analyses for five winter and summer seasons are used to obtain mean frontal positions for the Northern Hemisphere. These positions are found to differ in several important respects from earlier estimates based on mean-pressure and -temperature charts.

In winter, three axes of high frontal frequency, or principal frontal zones, appear which are termed the Pacific polar front, the Atlantic polar front, and the Eurasian polar front. There is also some evidence of a weak Atlantic arctic front. A fourth belt of high frontal frequency parallels the Rocky Mountains.

In summer, four principal frontal zones are delineated: a Pacific polar front, an Atlantic polar front, an Eurasian polar front, and a Siberian-Canadian arctic front.

The locations and intensities of the oceanic fronts are shown to be closely related to the sea-surface temperature distributions. The formation of a Siberian-Canadian arctic front in summer is attributed to the strong thermal contrast that develops along the borders of the arctic seas. The position of the Eurasian polar front in winter also appears to be affected by the thermal characteristics of the underlying surface, being most distinct where open seas adjoin relatively cold land.
Numerical Weather Prediction in the Soviet Union
Authors: Phillips N. , Blumen W . , Coté O.
Published: August 2018

This article gives a review of the research done in the Soviet Union through 1959 on the theory and practice of numerical weather prediction by hydrodynamical methods. Russian meteorologists have used the same geostrophic forecast system as have other meteorologists and have carried out a number of test forecasts with electronic computers. Comparatively little has been published so far in objective weather-map analysis, general-circulation experiments and the use of non-geostrophic equations.
Field Tests of a Sonic Anemometer-Thermometer1
Authors: John Robert S.
Published: August 2018

A Sonic Anemometer-Thermometer system for use at an operational airfield is described. The system provides data on net large-scale surface air movements (wind) and speed of sound (or virtual air temperature) by means of acoustic signals. The measurements are made directly over an operational runway, thus providing data from the actual area of interest. Field tests have shown that the temperature and winds measured over the runway are consistently different from those measured at the usual instrument-shelter locations. Surface wind shifts may occur at one place as much as half an hour prior to shifts at the other location, with dangerous operational conditions resulting. Wind velocities and temperatures measured over the runway by the sonic anemometer-thermometer are more representative of runway operational conditions than the measurements made by any combination of conventional instruments placed off the runway.
A Fallacy in the Use of Skill Scores
Authors: Appleman Herbert S.
Published: August 2018

Evidence is presented to show that the form of the Heidke skill score commonly used to evaluate forecast procedures is not reliable for the purpose for which it is intended. This is primarily because the standard against which the forecast accuracy is tested is not a true standard, since it is a function of the forecasts issued. Thus, even when applied to the same representative set of data, it is entirely possible for one skilled forecast technique to have a higher skill score but a lower forecast accuracy than a second skilled technique or an unskilled technique. A new skill score is proposed which retains the useful characteristics of the common skill score without its drawbacks. Finally, some brief comments are made regarding the weighting of data in a contingency table to obtain operationally more useful skill scores.
Construction and Calibration Details of the Thermal-Transducer-Type Net Radiometer 1
Authors: Fritschen Leo J.
Published: August 2018

The details of construction and method of calibration of an instrument used to measure net radiation have been described.
A Method for Assessing Hourly Temperature Probabilities from Limited Weather Records
Authors: Lackey Earl E.
Published: August 2018

The frequency distribution of hourly temperature for any month may be assessed with a considerable degree of confidence by use of a nomograph when only the mean monthly temperature and the corresponding monthly extremes are known. Moreover, the method is readily adaptable to computing-machine tabulation and solution.
Microwave Refractive Index Distributions Associated with the Texas-Gulf Cyclone1
Authors: Jehn K. H.
Published: August 2018

Microwave refractive-index distributions in the lower atmosphere through the various stages of development of the winter Texas-West Gulf of Mexico cyclone are presented by means of “composite” surface and 850-mb analyses, along with vertical atmospheric cross-sections. The resulting patterns constitute a partial and preliminary synoptic climatology of the subject phenomenon.
The Common Ground of Meteorology and Hydrology
Authors: Linsley Ray K.
Published: August 2018

This article is a brief survey of topics of mutual interest in hydrology and meteorology intended primarily for the members of these two professions whose special interests are somewhat removed from the common ground. The last decade has seen substantial progress in our understanding of the water balance and in our ability to put this knowledge to use. A rapidly expanding world population with a correspondingly rapid increase in water requirements for human, industrial, and agricultural uses during the next few decades will require still further efforts to increase our knowledge and develop solutions to new water problems.
Meteorological Rocketsonde Equipment and Techniques
Authors: Keegan Thomas J.
Published: August 2018

In the near future wind and temperature data at heights above 200,000 ft will be made generally available. This paper is designed to acquaint meteorologists with vehicles, sensors and reduction techniques used in collecting these data. The problems involved in establishing a rocketsonde network modeled after the radiosonde network are discussed.
The Divergence Equation as Related to Severe Thunderstorm Forecasting
Authors: House D. C.
Published: August 2018

The divergence form of the equations of motion is developed and the terms of the equation are related to several local thunderstorm forecast parameters. It is found that the divergence equation provides the physical basis for evaluating the validity of several forecast rules under differing synoptic situations. In order that the magnitudes of the several terms can be compared, a numerical solution for a particular severe local thunderstorm producing synoptic situation is shown.
A Preliminary Investigation of Thunderstorm Occurrence in Eastern Virginia
Authors: Cox Myron K.
Published: August 2018

Thunderstorms and associated weather in the region of Eastern Virginia are discussed, and a semi-objective technique is presented for forecasting the phenomena. A new stability value is presented as a convective forecasting facility. The forecast method herein described had an overall verification probability with dependent and independent data of 0.88 and 0.92, respectively.
Microwave Refractive-Index Distributions Associated with the Central United States Cold Outbreak 1
Authors: Jehn K. H.
Published: August 2018

Microwave refractive-index distributions in the lower atmosphere through the various stages of development of the winter cold outbreak in the central United States are presented by means of “composite” surface and 850-mb analyses, along with vertical atmospheric cross-sections. The resulting patterns constitute a partial and preliminary synoptic climatology of the subject phenomenon.
Errors in Wind Measurements Associated with Tower-Mounted Anemometers1
Authors: Moses Harry , Daubek Hugh G.
Published: August 2018

Towers distort the wind flow and thereby may produce errors in wind speed and direction measurements obtained by anemometers mounted on them. To study this effect, a comparison was made of 5000 hourly wind observations obtained from each of two Aerovanes operating simultaneously. One was mounted on a lattice-type tower and the other was mounted on a utility pole free from the tower wind-shadow effect. Both instruments were located at the meteorological field site of the Argonne National Laboratory. The results show that there was a substantial reduction in the wind speed indicated by the tower-mounted anemometer when the wind passed through the tower before being measured. For some wind directions, the tower-mounted anemometer gave speed readings appreciably higher than those of the reference anemometer. Wind-direction measurements were also affected. The data indicate that for precise work the tower wind-shadow effect must be considered.
The Tornado-Research Airplane Project, 1958–1959
Authors: Lee J. T. , David Clarence L.
Published: August 2018

This paper is a description of the Tornado Research Airplane Project during 1958 and 1959. The instrumentation of the aircraft, as well as the organization of the project, is described. A section on instrument calibration and a description of data reduction and processing are included. The results of a radiosonde comparison test made in 1959 are given, and these results are compared with the results of radiosonde comparison tests made during 1958. A sample of the graphical presentation that is available for each of the flights is shown. For the information of anyone interested in these data, a listing of all operational flights for both 1958 and 1959 is given.
Verification of JNWP-Unit Hurricane and Typhoon Forecasts for 19591
Authors: Vanderman Lloyd W.
Published: August 2018

During the 1959 season for tropical storms in the Northern Hemisphere, Joint Numerical Weather Prediction (JNWP) Unit computed operationally one or more forecast tracks for 11 hurricanes and tropical storms and 11 typhoons. The 500-mb barotropic forecast flow with the tropical vortex eliminated from the initial 500-mb analysis was employed as the steering current in obtaining these forecasts. A summary of 1959 forecasts and a table of verification of JNWP hurricane forecasts for the years 1956 through 1959 are presented. The improvement and deterioration in forecasts from one year to the next are discussed in terms of sample size, operational changes, and analysis and forecasting techniques specifically designed for forecasting trajectories of tropical cyclones.