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discussion: weather bureau service in CALIFORNIA 179

The establishment of additional Weather Bureau Stations in the Mr.
higher altitudes, as recommended by the authors, would also be of ' ® ^'
much use in predicting floods. The importance of the temperature of
the air, particularly in the mountains, is almost equal to that of the
precipitation. During the maximum discharge of the larger rivers,
all but a negligible proportion of the water comes from the higher
altitudes, the proportion probably being not unlike that of the annual
run-off. Very few of the Weather Bureau Stations are high enough
to indicate the conditions which give high rates of run-off. The for-
tunate fact that the Southern Pacific crosses the mountains at com-
paratively high altitudes, and is giving constant and valuable support
to the Weather Bureau, is of great assistance. The effect of high
temperatures in producing high rates of run-off has not received from
engineers the study which it deserves, and to this can be largely
attributed some of the apparently erratic results of the very wet
January of 1916. During the heavy storms of that month the river
at no time reached a dangerous stage, probably because the temperature
in the mountains was so low that the precipitation piled up in tempo-
rary storage as snow. The highest stage of the river reached thus far
in 1916, accompanied by a prolonged, heavy run-off (although at no
time dangerous), occurred in response to comparatively light precipi-
tation, accompanied by unusually warm weather during the first half
of February.

Colusa Basin comprises the northeast corner of the flood basin
of the Sacramento River. Back of the Reclamation Districts, which
include more than 120 000 acres, there is a water-shed of about 1 600
sq. miles. About 950 sq. miles of this are occupied by comparatively
level valleys and plains, and the remainder, producing most of the
run-off, is composed of the bare foot-hills of the Coast Range rising
to elevations of from 1 500 to 2 000 ft. The flood-control works now
under construction are designed primarily to handle the run-off from
these hills at a maximum rate of perhaps 25 000 sec-ft. There are
only four (all co-operative) stations in this drainage area, all of which
are below 200 ft. elevation. Rainfall records at these stations do not
necessarily give an index of the run-off. The first fiood of 1916, from
January 3d to 8th, aggregating about 110 000 acre-ft., was accompanied
by an unusually violent storm, averaging in the valley nearly 4 in.
of precipitation in less than 24 hours. This indicated satisfactorily
the crest of this flood 4 or 5 days in advance. The next and larger
flood occurred between January 24th and 2Sth, and was not accom-
panied by any unusual precipitation of record at the stations in the
water-shed mentioned previously. Had the stations been at the eleva-
tions at which the precipitation occurred, which caused this flood, they
would probably have indicated its size and time of occurrence. This
is inferred from the fact that this storm is shown clearly by the



180 DISCUSSION : weather BUEEAU service in CALIFORNIA
Mr. rainfall records at Kennett, which although 120 miles farther north,

Tibbetts . . . .

-■ and on quite a different water-shed, is at an elevation of 730 ft. The
wi'iter concludes that the vertical distribution of rainfall stations is
far more important, from the standpoint of flood control, than their
geographical location.

The work of the Weather Bureau in collecting and making public
with amazing promptness the actual conditions all along the river,
is of the greatest value. By 9 a. m. it is possible to ascertain, by tele-
phoning to the Weather Bureau, the precipitation at each station
for the preceding 24 hours, the stage of the river at 7 o'clock that
morning, and its rise or fall within the last 24 hours. The mail
service is so prompt that these records are usually received through
the mail on the day that they are issued. The writer has only
one suggestion here, and that is that more frequent observations
during critical periods, or, better still, the use of automatic instruments
giving a continuous record of the river stage, would be of the utmost
interest and value. For example, at Red Bluff, at the head of the
Sacramento Valley, the river sometimes rises or falls 15 ft. or more
in 24 hours. The variation is almost as great at Colusa, near the
head of the heavy flood-control works. The highest gauge at Colusa
is ordinarily within from 1 to 3 ft. of that at Red Bluff, and from
18 to 36 hours later. Daily readings at Red Bluff may miss the crest
of the flood by a number of feet, and render it that much more diffi-
cult to predict accurately the stage of water which will be reached
on the levees from Stony Creek to the Feather River.

The writer's conclusions with regard to the work of the Weather
Bureau, as it affects flood control and drainage, are:

Two observation stations in the ocean would be of more value, in
predicting several days in advance the occurrence of heavy storms,
than all the present stations in California combined. Regular infor-
mation from vessels in the ocean might be of much assistance.

A more uniform vertical distribution of the Weather Bureau
Stations, particularly in the higher altitudes, is desirable.

More importance and more study should be given by engineers
to the effect of temperature in the mountains on the maximum rate
of run-off.

The Weather Bureau has developed amazing efficiency and prompt-
ness in the collection and publication of river bulletins, and its local
officials are uniformly courteous and desirous of making their work
of the utmost usefulness, but the prediction of continued storms, and
prolonged high-water stages, for a sufficient length of time to be of
much use in flood-control work is physically impossible under present
conditions on the Pacific Coast. The timely warnings issued, however,
have been of inestimable value in saving life and property.



DISCUSSION : WEATHER BUREAU SERVICE IN CALIFORNIA 181

J. B. LiPPiNCOTT,* M. Am. Soc. C. E. (by letter). — The writer Mr.



wishes to express his appreciation of this paper concerning the work
of the U. S. Weather Bureau in California. This subject is of such
interest to the hydraulic engineers of the West that this Committee
(consisting of Mr. Binckley and Mr. Lee), representing the Southern
California Association of Members of the American Society of Civil
Engineers, was appointed for the purpose of reviewing this work. The
report of the Committee was presented at a regular meeting of the
Association, an evening was given to its discussion, a resolution of
commendation was passed, and its publication by the Society was
requested.

The work of the Weather Bureau and its predecessor, the United
States Signal Service, in arid America has been of great value to
engineers engaged in the study of the water problems of the West.
The writer is especially indebted to the Service for much useful infor-
mation. It is relatively an easy matter to maintain rain gauges, and
an exceedingly difficult one to maintain stream gauging stations
throughout a term of years. For this reason the engineers have had
to rely largely on records of the Weather Bureau and Signal Service
as a basis of their study of the available water supply for irrigation
and water power.

There is a constant tendency for the older bureaus of the Federal
Government to maintain themselves in the City of Washington without
adequate field inspection, particularly of the far western country. It
is not efficient, and in fact usually is very unintelligent for one to
endeavor to direct, year after year, from a desk in the Capital, field
operations on the far side of a continent. This lack of proper execu-
tive has not alone characterized the Weather Bureau for a number
of years past, but many other departments of the Government. This
habit was broken away from vigorously first by the Geological Survey,
and then by the Forest Service and the Reclamation Service.

The Engineering Profession should use its influence in obtaining,
if possible by co-operation vnth the Weather Bureau, an expansion
and improvement of its work along lines that will be of greater value
to this Profession.

In California there are two great hydrographic features: First, the
Pacific Ocean with 850 miles of coast line lying to the west, from which
all moisture is derived; and, second, the great Sierra Nevadas and
Coast Ranges of mountains that are the condensers which collect the
vapor from the clouds and put it into the streams. The rainfall in
the valleys of California is small, ranging from 5 to 10 in. in the Great
Central Valley, and from 10 to 15 in. along the coastal plains of
Southern California. The desert rainfall to the east of the Sierra is

* Los Angeles, Cal.



Lippincott.



182 DISCUSSION : WEATHEK bureau service in CALIFORNIA

Mr. less than 5 in. annually. The precipitation on the mountain crests
uipinco . ^^ enormously greater, the increase in depth of annual rainfall being
at the rate of approximately 0.6 in. for each 100 ft. rise in elevation
on the western slopes of the ranges up to some unknown limit for
from 6 000 to 8 000 ft. The water, both for the irrigation supply
and the development of power, comes from these high mountains, yet
in California there are eleven regularly established Weather Bureau
stations, all in the valleys and none in the higher mountains, the
one possible exception being on Mt. Tamalpais, which is a branch of
the San Francisco office on a foot-hill near that city.

Apparently, the original purpose of the Weather Bureau was to
be of primary aid to shipping, which is of first importance. Seven
of the eleven official weather stations in California are on the sea coast,
and the others are in low valleys. In California there is great variation
in the rainfall within short distances. For instance, at Fresno, in
the San Joaquin Valley, the yearly rainfall is about 7 in., and 30 or
40 miles away the precipitation on the Sierra Nevadas is from 50
to 60 in., yet there are three official stations in the Central Yalley
and none on this main range. In a horticultural State which relies
largely on irrigation for its success, and is greatly interested in flood
problems and inland waterways, this would appear to be a condition
to correct. The same argument applies in Southern California. If
it is impossible to discontinue any one of the seven coast stations, it
is essential that additional regular stations be established in the high
mountain drainage basins. Apparently, the cost of maintaining one
of the city offices would be enough to support two in a forest reserve
where a cabin could be built and the records kept in an open field.

There are some voluntary observers in these mountain regions, but
they are rarely at the higher elevations, or at points where maximum
precipitation occurs. These voluntary observations are usually frag-
mentary, and are not an adequate substitute for a regular station.

Both off the west coast of Europe and the west coast of America
the warm currents or streams of the ocean have a profound effect on
the climatic conditions of the regions on which they impinge. It is
quite possible that there is some variation or swing in these ocean
streams from year to year. Navigators talk of open and closed winters
off the coast of Northern Alaska, and there have been remarkable
groups of wet and dry years in California. Storms originate on and
travel easterly from the Pacific Ocean across the continent. So far
as the writer knows, nothing has been done, in a broad and systematic
way, to study the fluctuation in temperatures of the ocean water off
the Pacific Coast. There are light-houses at short intervals from
San Diego to Seattle, and others farther north. It would be a simple
matter, not accompanied by serious expense, for the Weather Bureau
to arrange with the Light-house Service for the taking of daily tern-



DISCUSSIOX : WEATHEK BUREAU SERVICE I>f CALIFORNIA 183

peratures of the water of the ocean, with a view of determining the Mr.
possible relations between changes of water temperatures and cycles ^''pp'°^°"-
of wet and dry years. There may be no such relation, but it is a
physical condition that might be studied to great advantage. The
fishing industry of the Pacific Coast is growing to prime importance,
and some believe that the schools of fish in their migrations are
influenced by the ocean temperatures and that the season's catch is
thus governed.

It is respectfully submitted that the work of the Weather Bureau
could be substantially improved, also, at the localities where regular
stations are now established. It is recognized by engineers, and also
by the old Signal Service, that precipitation records should be taken
on the level places rather than on pinnacles or near obstructions. The
U. S. Weather Bureau has published a record of the rainfall in San
Francisco extending back to 1849. This is a composite of observations
made successively at six diiferent stations. In 1892 the station was
moved to the roof of the Mills Building. There is available a rainfall
record, made by Mr. John Pettee, extending back to 1865-66. Although
it is said that the gauge observed by Mr. Pettee was moved to different
parts of the city several times, it is believed that it was always estab-
lished near the ground, as distinctive from the roof of a building.
For the 27 years prior to 1892 the Pettee record shows a reasonably
close relation to that of the Weather Bureau, being an average of
97.2% of it. Subsequent to this date (when the Weather Bureau
station was moved to the roof of the eleven-story Mills Building) there
was a decided difference in the ratio of the two records. For the
period, 1892-93 to 1900-01, the Pettee* record was 134.4% of the
Weather Bureau record. This may not be taken as conclusive of the
ratio of records maintained on the roofs of high office buildings and
those observed near the ground, but it certainly indicates a wide differ-
ence in the results. Other examples could be referred to.f

Again, in such a country as California, where a change of a few
degrees in temperature in the spring or winter is apt to mean the loss
of the fruit crop by freezing, it is not satisfactory to have temperature
taken on the roofs of high buildings. Occasionally, we are confronted
with reports of frozen fruit, and see some ice in the streets, but we
are assured by the official records of the Weather Bureau, taken at
its regular station, that the minimum temperatures have been well
above freezing. The reverse conditions exist in midsummer. When
attention is called to this we are told to apply some factor in correction,
but few persons outside the Service know what these factors are.
In the writer's opinion, these observations should be taken on the
surface of the ground, as it is not satisfactory to say that corrections

* Transactions, Am. Soc. 0. E., Vol. LXI, p. 561.
t Fanning's "Hydraulics", p. 64.



184 discussion: weather bureau service in California
Mr. may be applied to adjust this great mass of observed data to normal

Lippincott. j-,-

conditions.

There are a number of voluntary meteorological observers, mostly
in the valleys of California, who, year after year, send in records of
rainfall and temperature, whose stations are not inspected, and who
are not given personal instructions and encouragement as to the
method of their work. Although some of the rain gauges are in good
locations, others are not, and may be misleading. A distinction should
be made in the records. The writer knew of two old gentlemen who
kept a rainfall record for 20 years, from 1882 to 1902, at a place known
as Second Gerrote, at an elevation of 2 714 ft. Their gauge consisted
of three tin cans wired together and set out in the open lot to catch
the rainfall. The depth of rain was read in each can with an ordinary
foot-rule at the end of each storm, and the three observations were
averaged and carefully recorded in a notebook. Such interest in a
scientific subject should be encouraged by a visit and personal com-
mendation, and the furnishing of adequate instruments for observation
and instruction. The writer has never known of an extended field
inspection trip being made by any officer of the Weather Bureau to
these voluntary meteorological stations in California, the records from
many of which have been continually published for years. It is
probably not the lack of interest on the part of the local observers,
but rather because of the "system" that is passed down from
Washington.

A great deal of the work done by the men of the Weather Bureau
is highly valuable and greatly appreciated. Their prediction of frosts
is of greatest importance to the fruit growers of California; their
prediction of storms is essential to the mariner. These gentlemen
deserve full credit for the thoroughness of their organization, which
is believed to be the most extensive meteorological department in the
world, yet it is suggested that this service, good as it is, could be sub-
stantially improved, from the standix)int of the engineer, without the
necessity of large additional outlays.

Messrs. George S. Binckley,* M. Am. See. C. E., and Charles H. Lee,*

^'and''^ Assoc. M. Am. Soc. C. E. (by letter).— The Committee is gratified

^^^' to find that the discussion of the paper has been constructive, and has

covered all sides of the subject. The Committee has been actuated by

a sincere desire to get at the truth and to be of constructive service.

The discussions are indicative of similar motives.

Although none of the Weather Bureau officials has contributed
formally to the discussion of the paper, which is a matter of regret,
yet the members of the Committee have had informal personal discus-
sions relative thereto with the present Chief of the Weather Bureau,

* Los Angeles, CaL



DISCUSSION : WEATHER BUREAU SERVICE IN CALIFORNIA 185

Professor C. F. Marvin, and the official in charge at Los Angeles, Messrs.
Dr. Ford A. Carpenter. These gentlemen, though not always in 'and^^
accord with the conclusions reached, assisted in many ways in amplify- ^^^•
ing the Committee's information. The members of the Committee
desire to express their appreciation of the helpful suggestions and
the co-operative attitude of these gentlemen toward the work.

The Committee understands that, at the request of the Cleveland
Association of Members, the Local Forecaster, Mr. William H. Alex-
ander, of Cleveland, Ohio, addressed that organization on the subject
of its paper. The Committee has not been furnished with a copy of
this address, but was kindly loaned one by Dr. Ford A. Carpenter,
from his office files.

Before proceeding further, the Committee wishes to make clear
three points in which the paper may have misled those who read it.

First, the title and presentation of data might indicate that the
Committee's findings and suggestions applied particularly, or even
solely, to the State of California. This was far from the Committee's
intention, however, as it is recognized that California enjoys its share
— and a very full share — of the effort and funds at the disposal of the
Weather Bureau, and that the local Weather Bureau officials are
doing all in their power to obtain and distribute the information
desired by the engineers of the State. The conditions set forth in
the paper were regarded as typical of all the Western States, and also
the Central, Eastern, and Southern States. California was chosen
for detailed investigation because of the greater degree of first-hand
knowledge thereof possessed by the Committee. That there is equal
need for greater study of rainfall in the region east of the Rocky
Mountains is indicated by the strong editorial which recently appeared
in one of the leading engineering journals.*

Second, the Committee does not wish its advocacy of improvement
in the mountain climatological work of the Weather Bureau to be
interpreted as supporting the idea that precipitation data collected at
properly located mountain stations will yield all the information as to
water supply and its variations needed for the design of hydraulic
structures and projects. On the contrary, the Committee is in full
accord with Mr. N. C. Grover's statement, that stream-flow records
furnish the most reliable data for this purpose. It is unfortunately
the case, however, that the establishment of stream-gauging stations
must be limited to one or two points on the larger streams, on account
of the first cost and the upkeep. There are many projects, however,
both public and private, which depend on the supply from the tribu-
taries of large streams, or from small streams. There are also many
short stream-gauging records which do not extend over years of
deficient precipitation, and, without proper corrections, are likely to be

* Engineering News, August 17th, 1916, p. 321.



186 discussion: weather bureau service in California

Messrs. as misleading as precipitation records unsupported by stream-flow
'and^^ data. To fill these deficiencies, precipitation records judiciously used
^^^- in conjunction with the available stream-flow records are of great
value, and afford the only adequate information, obtainable at reason-
able cost, with which to supplement insufficient stream-flow records.
It is toward the filling of this gap, which every hydraulic engineer in
the West at least recognizes as a serious one, that the Committee's
efforts are directed.

Third, the Committee's primary idea, in formulating its sugges-
tions for improvement of the Weather Bureau Service, was not an
increase in the volume of data collected, although that might be an
incidental result, but an improvement in quality, to be obtained by a
more studied choice of locations at which data are observed, and
more intensive study and interpretation of the data thus obtained.
For instance, in the matter of precipitation data, the hydraulic engi-
neer wants to know : First, the average annual areal precipitation for
all portions of a given drainage area, and the annual variations there-
from; and second, the monthly, daily, and hourly precipitation at one
or more points in the area, depending on its size. As Mr. W. S. Post
well suggests, this information can be obtained for Pacific Coast
mountain drainage areas by determining the shape of the isohyetose
lines from a few years records at a number of well-selected stations,
after which one or two base stations would provide all the information
needed. (This, of course, would not be sufficient for regions where
a large proportion of the annual rainfall occurs in detached local
storms covering limited areas.) By working out a progressive pro-
gramme for a State along these lines, the total number of stations
reporting at any one time could be kept constant, although the
geographical location of stations would vary. As contrasted with
such a programme, there is the present more or less haphazard distri-
bution of rainfall stations, without regard to the ultimate usefulness
of the record. The Committee recognizes the fact that to plan and
execute such a programme would require much intelligent study and
supervision by a practical and technically trained field man. The
Committee wishes to emphasize again, however, that its efforts are
actuated by a desire to see generally inaugurated a progressive, prac-
tical, co-operative, and broad handling of meteorological problems, to
the end that these problems may be solved. Mechanically observing
data for the sole purpose of tabulation and accumulation in the
archives does not solve these problems, no matter how many stations
are reporting.

The Committee wishes to correct an error which was inadvertently
made in the paper. The number of co-operative stations in California
reporting precipitation in 1913, as shown by the Annual Summary, is
practically 300, instead of 192. Of these stations 8% are within



discussion: weather bureau service in CALIFORNIA 187

25 miles of the coast, 43% are in interior valleys and foot-hills, 7% Messrs.
are in the Great Basin and Desert, and 42% (instead of 29%) are in ^'and''^
regions of broken topography where elevations exceed 2 000 ft. Of ^'^^•
these, approximately 30 (instead of 21 as stated), were above 4 000 ft.
Hence, out of the total, 10% can be considered as mountain stations.
It should also be stated that subsequent to 1913 there have been pub-
lished reports of snowfall data at from 40 to 50 stations in the Sierra
Nevada Mountains. These data have been expressed in snow depths,



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