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is uniformly courteous and obliging in furnishing whatever data are
available; but, that these data have not a higher standard of reliability
and greater practical value is due, the Committee believes, more to a
lack of recognition of the great service that could and should be per-
formed by the Weather Bureau, than to any reluctance on the part
of those at its head to extend the scope and improve the value of its
work.

In conclusion, the Committee does not hesitate to express the
opinion that the questions involved in an improvement in the char-
acter of service rendered by the Weather Bureau may be discussed
by engineers with the most complete freedom, and suggestions may
be made without the slightest diffidence. Without in any way reflect-
ing on the unquestioned scientific attainments of the officials of the
Bureau, it is safe to say that the engineer who has to deal with the
practical questions of water utilization is better qualified to indicate
the source and character of meteorological data which will have the
greatest real value, than the detached and abstract observer of meteoro-
logical phenomena.

The conclusions arrived at by the Committee are the result of
mature consideration, and are now laid respectfully before the
Association.



discussion: weather bureau service in CALIFORNIA ITl

Disoussioisr



N. C. Grover,* M. Am. See. C. E, (by letter). — The writer is in Mr.
hearty accord with the suggestions made in this report for rendering
the climatological work of the United States Weather Bureau of
greater practical value to the communities and industries of California.
The desirability of collecting systematic records of temperature, pre-
cipitation, accumulation of snow and its equivalent in water, has long
been recognized by Weather Bureau officials, as well as by others who
need records of that character. The difficulty, as the writer understands
it, however, is in devising instruments that will record correctly the
phenomena desired, without daily attention, for it is unusual to be
able to obtain reliable observers at high elevations in the mountains.
Without such resident observers, or instruments that can be relied on
to record the data without attention for several weeks, the cost of col-
lecting the records becomes practically prohibitive. There is no doubt,
however, that the officials of the Weather Bureau will gradually de-
velop methods by which satisfactory records may be collected at high
altitudes.

The following statements (pages 162 and 163) seem to be likely to
be misinterpreted:

"In such regions the gathering of climatic data, as a basis for the
study of stream flow and water supply, should be carried on in moun-
tains within the productive portions of drainage areas.

********

"The practical usefulness of climatic data is in forming a basis for
the forecast of future stream flow variation. It is on the latter in-
formation that the magnitude or practicability of irrigation projects,
hydro-electric power systems, municipal water developments, flood-
protection works, or any other large engineering work, depending on
water supply or stream flow, is based. Such data have also great value
in the design of engineering structures for the control of water, such
as dams, spillways, head-works, bridges, levees, etc."

Though the statements are not definite in this respect, the reader
is left to infer that climatic data collected at properly located moun-
tain stations will yield all the information as to water supply and its
variations needed for the design of the important works mentioned.
The dangers attending the use of estimates of water supply based on
records of precipitation have been forcefully demonstrated by the
many failures of hydraulic works of all classes. Such failures hare
been especially numerous in the irrigated areas of the West, and should
serve as an object lesson not to be forgotten, but, unfortunately, many
engineers appear never to have learned the lesson at all. Therefore,
the inference that might be dravpn from the report is particularly fal-

* Washington, D. C.



Post.



172 DISCUSSION : weather bureau service in CALIFORNIA

Mr. lacious, in view of the reliance that many engineers, both in the East
and the West, continue to place on estimates based on records of pre-
cipitation, even though it has been demonstrated again and again that
such estimates are not only not dependable, but positively misleading.
Mr. William S. Post,* Assoc. M. Am. Soc. C. E. (by letter). — There is
one feature of the Weather Bureau Service which only has to be stated
to be recognized, namely, that this Bureau, as a matter of fact, has a
monopoly of publication. It is, of course, a national organization,
and perhaps cannot recognize local conditions to too great an extent,
but the writer wishes to emphasize publication as an important matter,
in addition to the recommendations of the Committee. There are
numerous rainfall records in California, and presumably in other
States, which are in the hands of private parties and cannot qualify
as official. These records are of the utmost importance because they
frequently go back as far as the early Seventies, and are fast disap-
pearing with the dying out of the original observers. We have obtained
or are maintaining some 60 stations alone in San Diego County which
have no official means of publication. The writer would suggest that
the Weather Bureau consent to publish all records in the State, in a
volume devoted simply to rainfall, to be contributed from all known
sources of information, the responsibility for the record being stated.
In this way an extremely important source of information will be
preserved.

In reference to this matter, the writer, alone and single-handed,
some two years ago, attempted to convince the head of the Weather
Bureau that the form of publication, in so far as it gives long lists of
"normals", is a needless incumbrance of the present reports. To state
it differently, what is required is not the mathematical interpretation
of differential variations, etc., but a plain tabulation of the observed
data. The first result of this, to the great relief of some engineers,
would be a publication, 8^ by 11 in., which is a standard filing size,
and the increase of the size of the type from a microscopic nonpareil to
a good book type. It may be possible to convince a physical scientist
that these normals have some significance, but most hydraulic engineers
will agree that they are an unmitigated nuisance in the present pub-
lications.

The writer has suggested to one of the members of the Committee
that, in case it is not possible to co-operate fully with the Weather
Bureau in this matter of publication, the Society itself or the Local
Association make permanent the present committee and undertake the
publication of the meteorology of California, combining as contribu-
tors all those who can furnish any data.

* Sau Diego, Cal.



discussion: WEATHEE bureau service in CALIFORNIA 173

In hydraulic calculations, certain stations have become in the nature Mr.
of base stations, and are very valuable for the purpose of restoring
broken records or years of no record in the same region. For this
reason it is a real loss to have a long-term station discontinued, merely,
as it vpould seem, because the voluntary observer has moved and the
Weather Bureau official has neither the money for traveling expenses
to inspect and secure another observer, nor funds to hire a paid
observer. The writer has recently expressed his regret at the discon-
tinuance of the splendid record at Fort Wingate, in Arizona, to the
extremely intelligent and competent Director of the Weather Bureau
at Santa Fe, N. Mex., and was told that his hands were absolutely tied
in the matter, that he could only secure a voluntary observer through
correspondence, and had attempted to do so. That is a case where,
because of the lack of an efficient field inspector, who could discover
observers, a record which dates back to 1867 has been broken for about
3 years. Numerous other instances could be brought up.

The suggestion is also made that the Weather Bureau take up the
study of local drainage areas for a few years, in order to determine
the local shapes of the isohyetose lines once and for all in that area,
and thereafter proceed with only one base station in that drainage
area. The writer has succeeded in drawing such curves on certain
drainage areas in Southern California by the establishment of some
fifty rain gauges. In some cases there are voluntary observers and
in others $1.00 per month is paid. About 15 gauges are examined
by one hydrographer, who is also a good rider and can crank a machine.
From a comparison of these curves, now that they have been established,
it is obvious that a very considerable reduction in these stations
can be made.

Charles T. Leeds,* M. Am. Soc. C. E. (by letter). — The genesis of Mr.
this paper was an address before the Southern California Association
of Members, on April 8th, 1914, by Dr. Ford A. Carpenter, Local Fore-
caster of the U. S. Weather Bureau, which paper has since been pub-
lished by the Weather Bureau under the title of "Flood Studies at
Los Angeles". The discussion of this paper at that meeting developed
the fact that the Weather Bureau, due to lack of funds and observers,
is unable to establish as many co-operative stations as it would
like to do. Dr. Carpenter stated that, if instruments could be fur-
nished from other sources, he felt sure the Chief of the Weather Bureau
and the Section Director at San Francisco would be glad, through
the co-operation of the Forest Service, to assist in making the observa-
tions. He also stated that as soon as these extensions were author-
ized he would be glad to instruct the observers and collate all data.

Messrs. Binckley and Lee, therefore, were appointed as a Com-
* Los Angeles, Cal.



174 DISCUSSION : AVEATHER bureau service IN" CALIFORNIA
Ml-, mittee, with the original purpose of investigating the possibility of



Leeds.



obtaining the necessary rain gauges and of recommending advisable
locations therefor. J. B. Lippincott, M. Am. Soc. C. E., then President
of the Association, later instructed this Committee to broaden the
scope of the report, as has been done.

The authors deserve commendation for the constructive recommen-
dations which they have made. The Weather Bureau has been of great
service in years past, and is now still further extending its usefulness.
It is hoped that what criticisms have been made in the paper will
be taken as meant only in a spirit of helpfulness.

Many who have not been in the Government service fail to appre-
ciate the limitations imposed by legislative restrictions and lack of
appropriations. These limitations should be borne in mind when con-
sidering such matters. It is hoped that public opinion may be so
awakened as to lead Congress to remove these restrictions and provide
adequate funds to permit the Weather Bureau to render to the country
the greater service which it should be enabled to perform.

The authors have done well to state in their opening paragraph
their purpose "to outline a plan for strengthening and extending the
mountain climatological work of the United States Weather Bureau
in California, so as to meet more widely and fully the needs of the
industries and communities of the State relative to water supply".
The paper deals only with this phase of the work of the U. S. Weather
Bureau. It may lead to a better understanding of the whole matter
to trace briefly here the development of the Weather Bureau, and state
the duties now assigned to that Bureau by law.

The service now performed by the Weather Bureau was originally
organized and carried on by the Signal Corps of the U. S. Army, and
included only meteorological observations at military stations for the
prediction of storms. To this was added in 1870 the duty of render-
ing reports relative to the stage of water in rivers. This service was
primarily for the benefit of navigation on the ocean and the Great
Lakes, and later included the interior districts and the great rivers.
By Act of Congress, on October 1st, 1890, these duties were turned
over to the present U. S. Weather Bureau of the Department of Agri-
culture. The duties then assigned to it were as follows :

"Forecasting the weather; the issue of storm warnings; the dis-
play of weather and flood signals for the benefit of agriculture, com-
merce and navigation; the gauging and reporting of rivers; the main-
tenance and operation of sea coast telegraph lines and the collection
and transmission of marine intelligence for the benefit of commerce
and navigation; the reporting of temperature and rainfall conditions
for the cotton interests ; the display of frost, cold wave and other
signals; the distribution of meteorological information in the interest



discussion: weather bureau service in CALIFOEISriA 175

of agriculture and commerce ; the taking of such meteorological Mr.
observations as may be necessary to establish and record the climatic Leeds,
conditions of the United States or are essential for the proper execu-
tion of the foregoing duties."

It is regrettable that no mention is made by the authors of the
storm warnings, sent out by the Weather Bureau, resulting in the pre-
vention of untold disaster and loss of life. Nor is there any mention
of the excellent system of frost prediction, such as has been developed
in Southern California. Evaporation studies are urged (and v?isely),
but the implication is that none has been made. The authors have
apparently overlooked the evaporation studies made by the Weather
Bureau at Lake Tahoe and the Salton Sea. No mention is made of
the careful and scientific studies, by the Aerial Research Department,
of the upper air currents, made not long ago at Avalon, Cal.

The authors seem also to have overlooked the fact that the typical
action of a storm center on this continent is to enter from the North
Pacific, moving thence south-eastward and then north-eastward across
the continent, and passing out into the Atlantic Ocean from New
England or the St. Lawrence Basin. The most severe storms, how-
ever, enter through Southern California and proceed eastward and
north-eastward across the continent. For the prediction of storms in
the central and eastern part of the United States, therefore, it is
essential that evidence of an atmospheric change or disturbance should
be gathered as early in its course as practicable, and its direction and
rate of progress must be carefully traced from place to place. Lt
is doubtless to facilitate this purpose that so many regular stations
are scattered along the coast. It must also be borne in mind that
the regular weather bureau station, being a central distributing station
for climatic information, must be situated so as to facilitate this col-
lection and distribiTtion of data. This of necessity requires that the
regular stations shall be in centers of population.

The writer, as a hydraulic engineer, realizes fully the need of
the information desired, and is thoroughly in sympathy with all
extensions suggested. He is unable, however, to agree with the fol-
lowing statement on page 168 :

'Tf lack of funds prohibits the establishment of new stations, there
is no reason why most of the existing stations could not be moved.
Such action would be rather hard on certain of the Weather Bureau
men, but would be of great benefit to the people of the State as a
whole, and tend to distribute the benefits of the service more equitably."

On the contrary, it is believed that this would benefit the hydraulic
engineer and his clients of California at the expense of citizens of
other classes, and even at the expense of hydraulic engineers in
other parts of the country. What, for instance, would become of our
navigation interests, if all regular stations were moved into the moun-



176 discussion: weathek bureau service in California

Mr. tains ? What would become of the weather predictions, now made days
■'^^^ ahead as a result of the early observations at regular coast stations?
The Weather Bureau was created to serve the whole of the United
States, and all branches of its work must be developed co-ordinately.
The work of one station or locality cannot be developed with reference
to the needs of that locality alone. Each section should be given
the best service possible, consistent with equally good service to all
other sections.

If, on page 170, line 9, there were inserted the words "by Congress
and the general public", we would have a clearer statement of the
truth, as the writer sees it, and it is not improbable that this was
the thought in the minds of the authors.
The statement would then read as follows :

"The staff of the Weather Bureau is uniformly courteous and
obliging in furnishing whatever data are available; but that these
data have not a higher standard of reliability and greater practical
value is due, the Committee believes, more to a lack of recognition,
by Congress and the general public, of the great service that could
and should be performed by the Weather Bureau, than to any reluc-
tance on the part of those at its head to extend the scope and improve
the value of its work."

As stated previously, the duties assigned by Congress to the
Weather Bureau may be briefly summarized as making climatic obser-
vations and forecasting weather (particularly storms) for the benefit
of agriculture, commerce, and navigation. This, broadly interpreted,
would include all extensions recommended by the authors; but irriga-
tion and hydro-electric development have proceeded so rapidly during
recent years that the Weather Bureau has been unable, with the
facilities provided by Congress, to keep pace with the requirements
of the hydraulic engineer. Some extensions have been made, as
already noted, but the attention of Congress should be directed to
the need of facilities for still greater work. The Engineering Profession
is probably in a better position to bring this to the attention of
Congress than any other body of men. It is hoped that the present
discussion will help to attain that end.

If the Weather Bureau has not sufficient funds to fulfill the duties
assigned to it (as it is believed it has not), and if there are other
allied duties which the Bureau should be directed and empowered to
perform (as it is believed there are), then Congress should pass the
necessary legislation to accomplish these ends.

The writer has had occasion, in connection with his work as a
member of the Board of Engineers for Flood Control of Los Angeles
County, to take up, with the present Chief of the U. S. Weather Bureau,
the question of establishing additional co-operative stations in the
different water-sheds in Los Angeles County. The Chief as well as



DISCUSSION : AVEATHEE BUREAU SERVICE IN CALIFORNIA 177

the local official and the Section Director of the Weather Bureau Mr.
have expressed their willingness to co-operate to the extent of their
ability.

Another needed extension of the service of the Weather Bureau
which has come to the notice of the writer is the lack of wind observa-
tions along the coast. This lack of information was brought home to
him when he attempted to make a study of erosion along the
California coast in recent years and the various factors affecting it,
such as winds, tides, ocean currents, etc. So far as the writer knows,
the only sea coast stations south of San Francisco for the observation
of wind velocities and directions are at San Diego and San Pedro.
The latter has been established only a short time, but will be of great
service. The one at San Diego, being sheltered by Point Loma, is
inadequate for showing wind velocities along the coast.

It is hoped that the Chief of the U. S. Weather Bureau will par-
ticipate in the discussion of this paper and will describe fully the
present work of the Bureau, its aims, its limitations, and how the
Engineering Profession and the general public can assist the Bureau
in making extensions of its present great service.

Fred. H. Tibbetts,* Assoc. M. Am. Soc. C. E. (by letter). — The Mr.
writer is particularly pleased with the constructive criticism contained
in this report, and in the subsequent discussions. There is a strong
and rapidly growing sentiment favoring the participation by organized
engineers in the discussion of public problems. Engineers are the
chief users of the data gathered by the Weather Bureau, and hence
should be particularly qualified to support it and to urge the extension
by Congress of its exceedingly useful work.

Among the many important matters listed by the authors as per-
taining to the Weather Bureau, the writer wishes to discuss the
relation of the work of that Bureau to flood control and drainage
problems, particularly in the Central Valley of California.

In the Sacramento Valley many important cities and towns, includ-
ing the State Capital, as well as large areas of rich farming land,
lie below the flood-pl&in of the river, and are partly protected by
incomplete flood-control and drainage works. The accurate prediction
of floods is a matter of the greatest importance. Every general flood
has been attended by losses running from small amounts up to sums
exceeding $5 000 000. The Weather Bureau deserves the greatest credit
for predicting all the important floods, and for the prompt collection
of the data issued in the daily river bulletins during the flood season,
as well as for the uniform courtesy and devotion of its staff. Under the
present organization, and with the limited funds available, however,

* San Francisco, Cal.



178 discussion: weather bureau service in California

Mr. it is impossible to predict gauge heights with any great degree of
"' accuracy, or more than 1 or 2 days in advance.

The typical winter storms of California are areas of low pressure
which become detached from the much larger area which remains more
or less permanently in the vicinity of the Aleutian Islands. These
detached areas are swept eastward over the North Pacific Ocean, by
the prevailing eastward drift of the atmosphere, until they impinge
on the western shore of the continent. Their progress eastward is
then determined by the direction from which they have advanced, and
largely by local conditions. The storms are frequently broken up,
or the direction of their movement is changed, by the high mountain
ranges. The location of high-pressure areas at the time the storms
strike the Coast is also important. A high-pressure area over Western
Canada tends to deflect a storm southward; such an area over Central
or Southern California tends to hold it to the north, and make it
move parallel to the Canadian boundary. In general, these storms
cannot be predicted on the Pacific Coast until they have actually
arrived, and as they move ordinarily at a rate of from 10 to 15 miles
per hour, storm warnings are too late to be of much value. Disastrous
floods in a big river system such as the Sacramento occur only as the
accumulative result of a number of such storms occurring in such
quick succession that heavy precipitation continues for a number of
days or weeks. If, when a heavy rainfall is occurring in the Sacra-
mento Valley, it was possible to know that there was or was not,
one, two, or more other storms a day or two off the coast, it would
then be possible to predict with much greater accuracy, and for a
much longer period in advance, the heavy and continued precipita-
tion which causes high and prolonged flood stages in the river. For
such work, two or three, or even one, station in the ocean from 500
to 1 000 miles off the western coast, would seem to the writer to be
of as much value as all the other stations in California taken together.
Such stations, if established in the ocean, would be not unlike some
of the lightships off the coast. Only a limited outlay, and a limited
number of observers would be necessary. The stations, of course,
should be equipped with wireless, so that storms moving over the ocean
could be reported immediately as to intensity, direction, and rate
of movement. It is probable that, if regular reports were received
from all ships equipped with wireless moving in the North Pacific,
many of the severe storms could be accurately foretold a number of
days before they arrived. One of the authors has suggested to the
writer the occasional special use of naval vessels. The lines of ocean
travel from Puget Sound to the Orient appear to go far enough north
to make such observations of value.



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