Practical Exercises in Elementary Meteorology

The tables which follow are those which are now in use by the United States Weather Bureau. They were first published in the _Instructions for Voluntary Observers_ issued in 189...

=Maximum and minimum thermometers= are usually mounted together on a board, as shown in Fig. 7, the lower one of the two being the maximum, and the upper the minimum. In the vie...

_A._ =Lines of Equal Temperature.=——Temperature is the most important of all the weather elements. It is therefore with a study of the distribution of temperature over the Unite...

The non-instrumental observations, suggested in the preceding chapter, prepare the way for the more exact records of the weather elements which are obtainable only by the use of...

The fact of the prevalence of different kinds of weather over the country at the same time is of great importance. It should be strongly emphasized by the teacher in the course...

In a letter dated at Philadelphia, July 16, 1747, Benjamin Franklin wrote to his friend Jared Eliot as follows: “We have frequently along the North American coast storms from th...

Before beginning observations with the ordinary instruments, accustom yourself to making and recording observations of a general character, such as may be carried out without th...

The chief interest and value of the instrumental work in meteorology are to be found not only in the taking of the daily observations at stated hours, but in the working out of...

The first daily weather maps were issued in connection with the Great Exhibition of 1851 in London. The data were collected by the Electric Telegraph Company and transmitted to...

The work outlined in this chapter is adapted to the lower grades in the grammar school. It is assumed that the pupils have already had some preliminary training in the simplest...

_A._ =Lines of Equal Pressure: Isobars.=——One of the most important weather elements is the _pressure_ of the atmosphere. This has already been briefly discussed in the sections...

The humidity of the air, as determined by the wet and dry-bulb thermometers or the sling psychrometer, and the occurrence or absence of dew or frost, should be studied together....

The determination of the direction of the wind (by means of the wind vane) and of its velocity (by means of the anemometer, or by estimating its strength) at different hours, un...

It is evident, from even the most general observation of the weather elements, that the temperature experienced at any place is very largely dependent upon the direction of the...

map, with the dot at the center of the _low_, and having the paper properly oriented, as already explained. Trace off all the wind arrows around the center of low pressure, maki...

We live in the laboratory of the earth’s atmosphere. The changes from hot to cold, wet to dry, clear to cloudy, or the reverse, profoundly affect us. We make and unmake our dail...

_A._ =The Decrease of Pressure with Height, as between Valley and Hill, or between the Base and Top of a Building.=——Make these observations with the mercurial barometer, if pos...

Select a file of daily weather maps for some month. Commencing with the first map in the set, observe the weather and the direction of the wind at a considerable number of stati...

_A._ =Cyclones.=——It follows from the two preceding exercises that some fairly definite distribution of temperature, depending upon the wind direction, should exist around areas...

So far no definite study has been made of the changes in the positions of cyclones and anticyclones. If these areas of stormy and fair weather always occupied the same geographi...

In this chapter a series of six consecutive weather maps is taken as the basis of the work. The study of the weather elements on such a series of maps gives a far clearer unders...

The study of the series of weather maps in Chapters V-VIII has made it clear that some fairly definite relation exists between the general flow of the winds and the distribution...

_A._ Study the whole series of six maps. Describe the wind conditions on each map by itself, noting carefully any system in the wind circulation that you may discover. Examine t...

Prepare a scale of latitude degrees, as explained in Chapter V. Select some station on the weather map at which there is a wind arrow, and at which you wish to study the relatio...

_A._ =Cyclones.=——Provide yourself with a sheet of tracing paper about half as large as the daily weather map. Draw a straight line across the middle of it; mark a dot at the ce...

temperature gradient. We saw that the direction of this decrease varies in different parts of the map, and that the rate, which depends upon the closeness of the isotherms, also...

Hitherto nothing has been said about the _weather_ itself, as shown on the series of maps we have been studying. By weather, in this connection, we mean the state of the sky, wh...

These observations may usually be profitably undertaken in the later grammar and in the high school years. The instruments described, while all desirable, are by no means all ne...

Attentive observation of clouds will soon lead to a familiarity with their common type forms. A series of cloud views,[7] with accompanying descriptive accounts, will teach the...

This work may usually be begun in the early years of the grammar school course, as soon as the non-instrumental observations have been satisfactorily completed. The scheme of pr...

The observational work already done, whether non-instrumental or instrumental, has shown that there is a close relation between the _direction of the wind_ at any station and th...

The study of atmospheric pressure is not easy, because the pupils cannot perceive the changes in pressure from day to day by their unaided senses. Especially difficult does this...

_A._ =Cyclones.=——Prepare a piece of tracing paper as shown in Fig. 52, making the diameter of the outer circle about 1000 miles[6] and of the inner circle 500 miles. Place this...

The first thing for any teacher to do who intends to establish a course in meteorology is to secure a supply of daily weather maps. Arrangements should be made to have them mail...

The special study of various problems connected with precipitation involves detailed observations of the amount and rate of precipitation of various kinds, measured by the rain...

In the work on the wind charts it is essential to proceed very slowly, in order that the best results may be obtained by the pupils. Some of the aberrant wind courses, which com...

The next, and last, step in our study of the correlation of the various weather elements concerns the sequence of weather changes at a station before, during, and after the pass...

_A._ =Cyclones.=——Something as to the control of pressure over the circulation of the wind has been seen in the preliminary exercises on the daily weather maps. We now proceed t...