Hawaiian Rainfall

By A. J. Henry

(To be published in the Monthly Weather Review).

At the conclusion of this paper, Dr. I. M. Cline requested, and was granted, 5 minutes in which to present some charts showing the distribution of precipitation in tropical cyclones.

Distribution of Rainfall in Tropical Cyclones
By I. M. Cline

(Abstract to be published later in the BULLETIN).

The hourly rainfall in all parts of several tropical cyclones entering the Gulf Coast has been charted. It was found in the case of moving cyclones that the heaviest rain occurs in the right hand front quadrant about 80 miles from the center. There is little precipitation after the center passes, and there is little also on the left hand side of the cyclone's path. In stationary cyclones the precipitation is essentially uniform in all parts.—W. R. G.

Discussion-Dr. C. F. BROOKS remarked that one on September 30, 1924, showed greatest precipitation in its western half, i. e., on the left hand side of the path. (This, however, was not a typical tropical cyclone, since it was comparatively weak when it entered the Florida Peninsula, but developed considerably in intensity as it progressed up the coast.-W. R. G.)

Tornadoes of the United States, 1916-1923
By H. C. Hunter

(To be published in the Monthly Weather Review).

The discussion following this paper largely centered on the great difficulty of determining whether a severe storm is a tornado or merely a straight blow. It is frequently not at all easy to establish with certainty the existence of a whirl.

PROF. E. G. LINSLEY stated that many tornadoes occur in central California, although Mr. Hunter's statistics do not show any. He (Mr. Linsley) suggested also that loss of life is not a proper basis for determining the intensity of tornadoes, since the latter often occur in sparsely settled districts.

In a subsequent communication, Dr. B. M. Varney states that what Prof. Linsley has called tornadoes, might more safely be described as violent dust whirls-never, except in perhaps one instance at Sacramento, destructive to buildings.

The Vocabulary of Weather and Climate

By Charles Fitzhugh Talman

One of the illustrations of the vast size and varied character of the meteorological vocabulary is found in the names of individual storms. The late Clement L. Wragge, when director of the Central Weather Bureau, at Brisbane, named every storm that appeared on the Australasian weather map. At least one of the names is likely to survive. Wragge used to pay off personal grudges by naming the most unpleasant weather disturbances after his personal enemies, and when he labeled a

particularly vicious storm "Conroy," by way of registering his hostility toward a prominent Australian politician, the episode attracted attention far beyond the limits of Australia. We may assume that "Conroy" will go down in history, along with Franklin's Storm, the Big Wind in Ireland, the "Royal Charter" Storm, Saxby's Gale, etc.

A meteorological phenomenon that science now almost completely ignores is ignis fatuus, or will-o'-the-wisp. Meteorologists will probably be astonished to learn that upwards of fifty names have been applied to this almost forgotten meteor in the English language, including the dialects. St. Elmo's fire is another phenomenon rejoicing in a variety of names. The rainbow has borne many names in many countries.

Dialectal and colloquial weather terms are continually finding their way into the formal literature of meteorology, and terms originated by meteorologists often become popularized—sometimes with results that breed confusion. "Cyclone" was coined for scientific use. The public has adopted it with an altered meaning, but modern meteorological usage diverges just as widely from the original definition. Meteorologists take the public to task for calling tornadoes cyclones, but the word "tornado” appears to be quite as serious a misnomer, as now generally used among scientific men.

An English meteorological dictionary, in order to realize the full measure of practical utility, should take account of all kinds of terms relating to weather and climate, and all the uses of such terms, that have been current among English-speaking people. Words that are erroneous in form and even those that serve no purpose but to enshrine erroneous ideas deserve to be included in the pages of such a work. Th word "sastrugus," though it is a perfectly indefensible singular of the Germanized Russian plural term "sastrugi" (widely used in the literature of polar exploration), having now made its appearance several times in print, cannot be ignored by the special lexicographer.

Every new idea brings a host of new words into the language, which have an amazing way of multiplying among themselves by means of combinations and derivatives. "Hygrothermometer" looked innocent enough when somebody first applied it to a composite instrument for measuring humidity and temperature. But somebody else called it a "thermohygrometer," and soon each of these terms began to form derivatives. At the same time corresponding "-scopes” and “-graphs” made their appearance and these also bred derivatives. Terrifying possibilities are suggested by the existence of such a word as "barothermohygroanemometer."

Cloud nomenclature has been prolific in new terms; mostly superfluous, though some cloud-masses have not attained the recognition they deserve.

One of the formal tasks of meteorological lexicography is to record the great number of specific definitions that have been prescribed or proposed, from time to time, for such terms as "drought," "thunderstorm," “calm,” “gale,” etc.—(Author's Abstract.)

Discussion-DR. DINSMORE ALTER, while recognizing the need for an exhaustive glossary, 15,000 words or more, for meteorologists, wished to stress the even greater, immediate need for an elementary glossary, say, 1000 words, for those who are not meteorologists, but whose work requires a limited knowledge of the subject.

Teaching Climate by Lantern Slides
By R. DeC. Ward

Professor Ward gave those present a very pleasant trip across the southern part of the country from Florida westward and back through the center. En route he indicated the effects of the weather and climate that could readily be discerned from a car window. His climatic train that left at 1.19 P. M. came in as scheduled on the dot at 1.39 P. M. Mr. Brooks and Mr. Tarr complimented the speaker on his interesting climatic profile of a new sort. Mr. Tarr asked for a trip around the world.

The Climate of Trinidad

By P. E. James

(To be published with the discussion in the Monthly Weather Review).

Climate and Weather Influence on the Fruit Industry of the

United States

By J. B. Kincer

In all agricultural and horticultural operations there are two basic meteorological influences which have an important bearing on production. The first of these is climate and the second weather. Where topography and soil are favorable, climate represented by average weather condition determines the areas of potential production, while the current weather operates to influence yields from year to year.

There are certain characteristic warm-climate fruits, including the citrus, olive, date, and fig, while some others, such as the apple, cherry, currant, gooseberry, and cranberry thrive best in comparatively cool regions. By reason of these rather divergent climatic requirements for different varieties of fruit, some are grown principally in the Southern States, while others are the dominating varieties farther north. There is, however, a rather definite poleward limitation on growth, the northern limit for the hardier varieties corresponding roughly to a mean winter temperature of 20°.

Citrus fruits are of tropical origin and, consequently, culture of these in Temperate Zones has very definite climatic limitations. The bulk of citrus in this country is now produced in California, and the lateness in blooming there renders them comparatively free from frost danger until the fruit has practically reached maturity. This makes the susceptibility to harm somewhat different from that in the case of deciduous fruit, as a relatively large bulk, instead of a bud or a bloom, is involved. Occacionally many millions of dollars' worth of oranges and lemons are lost by freezing, and orchard heating is practiced on a large scale.

The weather risk in fruit growing in the United States is relatively much greater than for most other crops, principally because of low winter temperatures damaging twigs or buds, or spring frosts killing advanced buds or blooms. The type of winter injury in the North is rather different from that in the South. In the normally colder climates, damage is more frequently associated with a lack of proper maturity of twigs or buds in fall, while in the South there is more danger of premature swelling of buds by reason of a short period of unseasonably warm winter weather, which renders them more susceptible to succeeding cold.

While winter injury is important in deciduous fruit, the greatest harm usually occurs in the early stages of growth, to the blossoms or young fruit just set. An injurious frost or freeze will cause much greater permanent damage after the fruit has set than during the bud or blossoming stage, because the critical temperature for the very young fruit is somewhat higher, and also by reason of the fact that there is a range of several degrees between the temperature at which all the buds or blossoms on a tree will be killed and that at which a goodly number will escape by reason of more favorable location or different stages of development of individuals. There are often four or five times as many blossoms on fruit trees as are required to set a full crop, and a frost that leaves a fair percentage unharmed may be actually helpful by thinning the blooms. Because of this, orchardists often at first over

estimate the amount of damage after a spring frost at blooming time.

The low temperature danger point for fruit blossoms, or for fruit just set, ranges in most cases from 27° to 29°, and varies only slightly for different varieties, though in the case of apricots, plums, and prunes it is somewhat higher. Well developed buds will withstand a lower temperature than after they have opened. The physical process which enables them to withstand temperatures considerably below freezing is the sub-cooling of their capillary liquids. This cooling below the freezing point of water, without the actual formation of ice, is due largely to the presence of chemical substances held in solution.

The principal cause of the greater frost risk to fruit than to most other agricultural products is the lack of control of the vegetative epochs in spring. Most other crops are annuals, and planting can be delayed until the frost risk becomes small or even entirely eliminated. In the case of fruit, even in an average year, there is very little margin between the date of the last killing frost in spring and the blooming dates. Records covering a long period of years in Ohio show that the apple blooms there on the average only about five days later than the average date of the last freeze, while in 40 per cent of the years freezing weather occurs after full bloom. In the case of some earlier-blooming fruits, such as the cherry and plum, the margin is in favor of the frost by two or three days on the average. These records show also that, in this locality, there is a very close relation between the temperature during the last ten days of March and the month of April and the time of blooming, the coefficient of correlation between the mean temperature for this period and the date of blooming being +0.88.

Aside from the heavier winter injury in the Central-Northern States than elsewhere, there is no marked variation in frost risk to fruit in different sections of the country. That is to say, the earliness or lateness of blooming in relation to the time of last killing frost in spring is substantially the same in all sections, and this is true with regard to difference in general elevation. The average date of retardation in blooming from South to North is approximately one day for each 15 miles, and the lag of the average date of the last killing frost in spring is substantially the same. Again fruit trees bloom progressively later at an average rate of one day for each 100 feet with increase in elevation, and the average date of last killing frost has a corresponding lag.

The foregoing statements as to elevation refer to general differences in altitude and do not hold in local variations in topography. Great advantages may be had in selecting locations for orchards where the local surface is uneven, especially where alternating slopes and depressions obtain, in which cases the lower ground should be avoided. The importance of this matter has been emphasized by some recent records made by the Weather Bureau in orchard temperature surveys in California For example, among some forty stations operated in a certain district, two were located about one-third mile apart; one at a elevation of 1,975 feet on sloping ground, and the other in an abandoned orchard on lower land of 825 feet elevation. On a cold radiation night in 1924 a minimum temperature of 25.1° was experienced at the lower station, while the lowest reached at the higher point was 48.1°. This explains why the lower orchard had been abandoned as unprofitable. Unfortunately, many orchards in this country have been planted without regard to local topography, and to this may be ascribed, in considerable measure, the heavy frost damage from time to time.

So far, orchard heating by burning a large number of small fires has proved to be the most effective and economical method of protecting from frost. More and more attention is being given to the matter, stimulated by the success of those who are protecting their orchards in this manner. It has been demonstrated that, in general, orchard heating pays, and if it is done in a careful, painstaking manner, with ample equipment, there probably are few orchards where the heaviest frost likely to be experienced can not be successfully fought.-(Author's Abstract.)

Discussion-DR. C. F. BROOKS commented on the high degree of accuracy of the Weather Bureau's fruit-frost forecasts and cited one instance in the Winter of 1923-24 when a forecast of a 25.5° F. minimum temperature, the lowest of the winter, was verified to a tenth of a de

gree.

DR. I. M. CLINE stated that similar service has been rendered for several years at New Orleans in the interest of the sugar cane growers and that a very large saving is effected thereby each year.