Evening star., 1936-01-16

The seasonal temperatures over much
of the great Midwest farming section
are profoundly affected by barometric
pressures three and six months previous,
thousands Of miles away.
The weight of the atmosphere on thei
Arctic and Antarctic Circles during the
Spring, for example, apparently has
good deal to do with the temperature OF
Kansas City tie next Fall.
So notable is the relationship that it
now is possible to predict with a high
degree of probability whether season
will be warmer or cooler than normal
and with somewhat less probability how
great will be the departure in either
direction. There still is big chance
for error, but a prediction based on the
formulae worked out by T. A. Blair and
A. G. Tophil, United States Weather
Bureau forecasters at Lincoln, Nebr, is
a great deal better than guess. Hitherto
such a prediction could have been very
little better, Weather Bureau experts
claim.
The work of the two meteorologists Is
an extension of the titanic statistical job
carried out at the Weather Bureau here
by c. w. A. workers under the direction
of R. H. Weightman. In this work,
which still is far from complete, single
correlations were worked out between
temperatures of places in the United
States and pressures all over the world
at Sc stations altc gether. Some remark
able RELATIONSHIP were revealed, al
though none of the correlations was
high enough to be used in actual FORE
casting.
Blair and Tophil extended the work
by making double correlations, much
more involved procedure. They have
obtained, however, some much higher
correlations.
They worked out their relationships
for an area comprising a large part Of
the grain belt. 1t includes most of the
DakotaS, Minnesota, Iowa, Kansas, Ne
braska and Missouri. Here are the re-
suits:
There is a correlation of 76 between
the Autumn Temperatures of this region
and the barometric pressureS the pre-
vious Spring at Nome, Alaska, and the
South Orkney Islands, a tiny British
possession south of Cape Horn and al
most on the Antarctic Circle. Between
the temperature and the barometric
pressure at Nome there is positive cor
relation of 43 With the barometric
pressures over the South Orkneys the
correlation is ST. When the two are
combined the much higher figure is
obtained, although, curiously enough,
there was practically no relationship at
all between the Arctic and Antarctic
preSSures.
Records are available for % years. For
more than 80 per cent of this period the
pressures and the temperatures "agree in
sign" That is, when the preSsureS indi-
Gated an Autumn colder or warmer than
normal, this was the actual result. The
diSagreements came when the forecasts
were barely on one side or the other Of
the normal line. In every case where an
average departure from normal Of more
than one degree Fahrenheit in the tenn
peratures was forecast from the pressures
there was complete agreement in sign"
There is a correlation of "a between
the Winter temperatures of this area and
the pressures the preceding Autumn at
Dutch Harbor, Alaska, and the preceding
Summer at Honolulu. Departures are OF
the same sign SIS per cent of the time.
When a departure of as much as one or
more degrees from normal was indicated
the forecasts were correct rs per cent
Of the time. The calculated temperature