218 MONTHLY WEATHER REVIEW MAY, 1935
(1) The larger part of the Sierra Nevada, escluding tlie foothills, appears to have an average seasonal variability -
of over 30-per cent. (2) West of this lies a long belt which includes most of the foothills and a conside&lde strip along the eastern side of tlie Iiiterior Valley, where a variability under 30
per cent is characteristic. This belt seems to be con- tinued in ti fan-shaped area northward and northeastward into the semiarid region of northern California.
(3) West of No. 3 variabilities increase, so that a
large part of the eastern Interior Valle and all of its
Coast Range country north of San Francigco Bay, show variabilities well over 30 per cent. Between region 3 and the coast one may distinguish two fairly definite regions, as follows:
(4) In the northern ‘Coast Ranges, in an area which includes perha s the western third of them, variabilities
There is also an apparently well-marked increase in variability from about 20 per cent in the northern part of the area to about 30 per cent around San Francisco Bay. Tracing the figures still southeastward within the Coast Ranges, one finds them rising irr over 40 per cent in the ranges north of ionterey Bay, decreasing to somewhat under 40 in the region east of the Bay, then rising to over 40 in t,he southern Coast Ranges. (5) The southern Coast Ran es average distinctly
it increasing southeastward and eastward into the high values of the southeastern desert.
(6) The southeastern desert is characterized by an extraordinary range of variabilities, indudin the unac-
Lake an the maximuni value at Ba dad. e desert is, in the matter of average seasonal variabilities, clearly to be
western part, together with a consiclerab T e portion of the
are considerab P y lower than they are east of this region.
z’larly to
higher in variability than the nort B ern, the magnitude of
countabl small variability at, Lone Pine nor 8 of Owens
a B (7) Southern California west of
distinguished from the forbiddin country at its back. I B variabilities largely stand mi d way between those of the desert rainfall and those of the fairly dependable rainfall in central and northern California. An exception to this condition is seen in the country north and east of San Diego, where the variabilities appear to be of the same order as those in central and northern California.
CONCLUSION
The foregoing iiiaterial would seem to sugest that tlie most ini ortant subjech for future studies of this
1. With the frequency polygons here resented as a
(a) the relation of the most frequent seasonal totals of rainfall to the “normal” or arithmetical average amount; (b ) the probabilities of occurrence of the most frequent amount; !c) the probabilities of occurrence of the
“ normal ” aiiiount ; (d) the most robable seasonal aniounts above and below the “normay.” 3. The duration of periods (one or more seasons) of rainfall above and below the normal. 3. The averages of seasonal rainfall during periods of escess and deficiency. The basis for such studies as those outlined above is constantly growing better. At this time (end of the 1924-25 rainfall season) five seasons in addition to those used in this paper have increased the value of the record. Many stations former1 in the “short-period” up now have moved into the “%ng- eriod” grou and ave data
importance is the increase in the number of stations having a t least 10 seasons of record. These should, by filling many a ga in the re‘seau of stations, greatly aid in any future wort on the problem.
type on Cali F ornin rainfall should be:
point of departure, the determining of the P acts regarding
for 25 seasons or more. #hat is per 1 aps of greater
NOTES, ABSTRACTS, AND REVIEWS
INTERNATIONAL COMMISSION FOR THE INVESTI- GATION OF THE UPPER AIR
[Reprinted from Nature, no. 2898, May 16, 1925, pp. 781-7621
A meeting of tlie International Coniniission for the Investigation of the Upper Air was held in London on April 17-23.
At the meeting of the commission in Bergen in July,
1921, the commission adopted the view that the inter- national publication of the results of the investigatioii of the up er air ought to be resumed, and that an inter-
contributions from the different States, so that the re aration and com ilation of the results should not
which undertook the work. Unfortunately, it did not prove practicable, in the stringent economic times which followed the meeting of 1921, to obtain the funds which were necessary to carry out the reconiniendations of the meeting at Bergen. In consequence of this, Prof. V. Bjerknes, who had been president of the coni- mission, resigned his position, as he could not spare the time from his purely scientific work to carry out unaided the large amount of work involved in the preparation and ublication of the international upper air results. Sir iapier Shaw, then president of the International Meteorological Committee, took over the presidency of
the commission at the request of the members.
national % ureau should be established and supported by
in p P uture be done a t t R e sole cost of tlie national service
Various methods for securing the object of an inter- national publication of upper air results hare been con- sidered or tried experimentally since t$at time. No satisfactory solution of the question has been achieved. A short meeting of t.he commission was held after the international conference at Utrecht in 1923 at which tlie results of tlie inquiries were briefly surveyed, and a
preliminary discussion took place on the most appro- priate form for an international publication. In 1921, at the meeting of the Int.ernat,ional Union for Geodesy and Geophysics at Madrid, the union voted the sum of 5001. toward the expenses of ublication
van &erdingen, the director of the Meteorolo ical Institut,e of Holland, promised si contribution of a Q out 1001. for the same purpose. The meeting of the conimission in London was con- cerned riniarily with the consideration of the form which t e spscinien ublication should take. Repre- sentatives from the fol owing countries attended : France;‘ Captain Wehrl6: Germany, Professor Hergesell; Great Bntain, Sir Napier Shaw. Sir Gilbert Walker, Capt. C. J. P. Cave, Lieut. Col. E. Gold, Mr. L. H. G. Dines, Mr. L. F. Richardson; Holland, Professor van Ever- dingen, Professor van Bemmelen; Italy, Lieut. Col. Matteuazi, Professor Gamba; Norway, Doctor Hessel- berg; Russia, Doctor Molclianoff; Spain, Colonel Mese- guer. The meetings of the conimission were divided
of a s ecimen volunie of upper air data, an R Professor
P R
M ~Y , 1925 MONTHLY WEATHER REVIEW 219
into business meetings and scientific meetings, on the ground that a right solution of the questions which the commission had to consider could only be achieved by a correct appreciation of the scientific principles in- volved. There were four business meetings and three scientific meetings. At the h t meeting of the commission on Friday, April 17, the president read a letter from Mr. la Cow,
director of the Danish Meteorological Service, giving the commission the welcome news that four wireless stations would be in o eration in Greenland during the coming summer, at lngmagsalik. Julianehaab, God- thaab, and Godhavn; and that all four stations would be equipped with instruments for observations of pilot balloons. The work of the four stations as regards investigation of upper wind would be coordinated by wireless with the view of obtaining simultaneous ascents to reat heights from all stat-ions at the same t.ime. fn a communication from M. FontsBrB, Barcelona, an account was given of some observations on oscillations of short period, indicated by the well known oscillations of the motion of pilot balloons, as seen in a pilot balloon theodolite. These oscillations appear to have a period of about three seconds, and do not appear to be due to natural oscillations of the balloon. The c.onimission decided to recommend that a similar investigation should be undertaken in other places, and that the influence of the size and form of the balloon on the character of the oscillations should be explored and that a comparison of the oscillations observed in balloons with those observed in the tension of kite wires should also be made. After some discussion of the use that should be made of the funds laced at the disposal of the president, the
publication of a specimen volume of upper air results for
1923 and 1924, and that in the specimen volume the ob- servations ob tained from ballon.-sonde and similar records from the places selected for international investi ation,
tails, and that the tables should be supplemented by graphical representation on “ tephigrams.’ This is the name given to the representation of the results of the ballon-sonde ascents, by plotting corresponding values of tern erature t , and entro y 4, which is pro ortional to
representation, w ich was invented by the president and explained by him at the scientific meeting, is peculiarly appropriate for resenting the results of ten1 wature
immediately the relation of the temperature gradient observed in the ascent to the adiabatic gradient for dr air and the adiabatic gradient for saturated air. I% shows the energy which would be required to raise air vertically in the atmosphere under the conditions of the ascent, or alternatively, the energ that would be set
the conditions of the ascent. It also has the great advan- tage of presenting these results in a diagram of very mod- erate dimensions, even when observations at heights of 50,000 feet or more are included. Considerable discussion took place on a proposal sent by Doctor Marvin for concentrating all the international ballon-sonde ascenta in any one ear into a single month.
tion to ascents on single days in other months of the year, was advocated by Lieutenant Colonel Gold a t the meeting at Bergen in 1921, but it was rejected b the
upper-air investigation should be devoted to obtaining
commission a ecided that they should be applied to the
should be published in the form of table3 giving B ull de-
the P ogarithm of otentiaftemperature T. $his form of
(and humidity) o g servations in the upper air. P t shows
!l
free in a kilogram of aw rising in t i e atmosphere under
The proposal to obtain ascents B aily for a month in addi-
commission on the ground that the funds availab 9 e for
5 2 0 3 8 -2 5 t 4
results for detailed investigation on the lines adopted by the Norwe ian Geo hysical Institute. After much dis- cussion of !boctor damin’s proposal, it was agreed that countries participating in the international investigation of the upper air should be asked to make, so far as possi- ble, daily ascents distributed throughout a month in each vear, the month to be selecked by the International Com- hission, these ascents to be additional to those indicated in the sc,heme of international days prepared by the com- mission at Bergen for the years up to 1938. The first month selected for this more estcnded investigation is
May, 1926, and the nest month is October, 1927. (It was considered that the time was too short to warrant an “international mont.li” in 1925, but it was agreed that any ausiliary ballon,-sonde results which any country might be able to make, should he made in August.) In the course of discussion of this resolut,ion, Professor Hergee11 emphasized that the international investiga- tion of the upper air has two as ects, the world aspect
over a month woulcfbe appropriate, and from the regional aspect, ascents concentrated into shorter periods of time, and made more fre uently, would lead to better results. Doctor Sinipson, fo ? lowing up this line of thought, made t.he su gwtion that the commission itself should deal only
coniniissions to deal with regional aspects. The com- mission eventual1 decided that the regional aspect could, in the meantime, Be dealt with satisfackorily by the nomi- nation of deputy presidents in the following different regions : Europe, with Russia, Siberia, and North Africa; North America; the East Indies and the Philippines: Australia; South Africa; South America. It was agreed that the six ascents left at the disposal of the president should be concentrated in the international months, and the exact dates in the diflerent regions should be left to the deputy presidents for these regions. Doctor Marvin was designated as dcput president for North America
The question of ado ting an international formula for
Weinberg (Leningrad), led to the appointment of a sub- conimission to consider this and other questions relating to balloons, a.nd to report to the nest meeting of the commission. The members of the subcommission are: Professor Her esell, president, Doctor Hesselbeg, Mr.
Doctor Marvin, and Mr. Fujiwhara. The importance of ai lane observations, and t,he
was emphasized by Captain Wehrl6, and the commission decided to ask for complete articulars of the instru-
niunicated, with the view of their ublicntion in collected
.& regards the future, it wns decided that the question of a regular international publication could only be settled satisfactorily after the specimen volume had been issued and considered. The question of the publication of results after 1924 was, therefore, remitted to the nest meeting of the commission, which it is ant,icipated will be held at Prague in 1927.
* * * The outstanding impression left by the meeting may be illustrated by a remark to mo of one of
the foreign delegates :
What I like about this international work is the way everyh? is ready to help things forward; the only consideration being, the thing good?”
and the regional as ect. From t f e world aspect, ascents
with t K le world aspect and should appoint regional sub-
and Mr. J. H. Field for t K e East Indies.
the rate of ascent of B alloons, put forward by Doc.tor
J. S. Dines, % octor Molchanoff, Colonol Matt,euzzi,
difficulty of securing satis T actory instruments for them,
merit-s and methods used in di 2 erent countries to be coin-
form by the French meteorologica P service.
It is very pleasant. E. GOLD.