Evening star. [volume] (Washington, D.C.) 1854-1972, 1931-04-04
HOLDS DER|NG SEA
IS CUTTING LIFE OF
WORLD IN HALF
w. D. Lambert of GeodetiC
Survey Makes Statement
in Bulletin.
SAYS EARTH'S ROTATION
UPON AXIS is SLOWER
Water Dragged Down by Moon
Declared in Friction With
River Bottoms.
BY THOMAS R. HENRY.


The life of the world is being cut in
half by Behring'S Sea, between Alaska
and Siberia.
Such is the implication Of calcula-
tons presented by w. D. Lambert Of
the United States Coast and Geodetic
Survey In q bulletin just issued by the
National Research Council.
The rotation of the earth on It's axis
Is slowing down, the report points out.
Approximately 5000, 900 900 years hence
the globe will make a complete revolu-
ton only once a month and the month
itself will be much longer. This con-
dition will be brought about, Lambert
explains, by the accommodating effects of
friction by the tides. Water, dragged
by the pull of the moon, Is in friction
with the sea and river bottoms. A
small part of the tidal energy Is trans
formed into heat by this friction, Just
as is the result when two sticks are
rubbed together.
Planet Tern From SUN.
Now the energy transformed into
heat by this tidal friction, Lambert
says, is part of the rotational energy
of the earth. At least two billion years
sun with enormous force and given
spinning motion upon its axis which 1t
has kept up ever since. 1t Is part of
the energy of that original casting OF
which keeps 1t in rotation, just as the
energy required for q base ball to spin
is contributed to 1t by the muscles of
the pitchers arm.
The rotational energy of the earth Is
calculated at approximately 100 billion
billion billion foot pounds. This
energy Is being turned into heat and
wasted by the tidal friction, it is
estimated, at the rate Of approximately
SO, 900 900 900 900 foot pounds a second.
This is extremely small compared to
the enormous amount of energy rep
resented by the swift rotation Of the
earth, but, given enough time, 1t will
prove fatal. And about two-thirds of
the whole wastage Of energy Is due tc
the peculiar formation and position o.
Behring'S Sea.
Shallow Seas MASTERS Of Energy.
plains, the tidal friction is very small,
due to complicated physical reasons.
1t becomes significant in the large,
shallow seas opening into oceans.
where the great bulk of the tide
originates in the open ocean and drags
along the whole bottom. Bering Sea,
approximately 100000 square miles in
area, approaches nearest the ideal body
of water for this effect. The Yellow
Sea and the English Channel also are
great MASTERS Of energy, but their con-
tributionS are insignificant compared
to that Of the shallow extension Of the
North Pacific, which becomes verit-
able Achilles heel of the world.
The estimates of the energy loss are
very uncertain. Lambert points out, but
accepting them at their face value the
rotation of the earth Is being slowed
down about q second every 100 900 years.
Given time enough and the earth will
always turn the same face toward the
moon and earth and moon together
will continue their annual journey
around the sun like two ends of a
dumb-bell. The earth's day VIII be
month long.
But, Lambert says, for reasons so
complicated that 1t is almost impossible
to picture them in words, this same
tidal friction Is pushing the moon fur
Their away from the earth so that even
tually 1t will be so far away that 1t
will not raise any tides. Slight tides
are now raised by the sun. These will
continue after the moon tides stop and
the effect probably win be to bring the
moon nearer to the earth again until
the two bodies crash But, so far as
being an abode Of life Is concerned,
the earth will have ceased to function
when the regular procession Of day and
night cease.
Friction May Have Been Greater.
In the distant past, Lambert points
out, shallow seas were much more ex-
tensive than at present, and there may
have been considerably more tidal fric-
ton.
las in imagination we 60 further back
into the past" he says, I'VE find the day
and the month getting shorter and the
moon getting nearer to the earth. The
decreasing distance of the moon i'm
plies that tidal friction would tend to be
greater, other things being equal, In the
ing effect varies inversely with the dis
lance The more rapid rotation Of the
earth would diminish the period of tidal
forces. The general effect would be the
results Of tidal friction to develop at q
more rapid rate ! nthe remote past than
now.
IF the moon in the past was much
closer to the earth than now, might it
not at one time have been almost in
contact with 1t, thus arising enormous
tides. If We look still further back,
might not the moon and earth have
formed q single body? A fragment
separated from the parent earth and
formed the moon and tidal friction has
done the rest, frightening the day and
month and making the moon recede
from the earth"
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