Evening star., 1939-06-06
Of Stors, Men
And Atoms
Notebook Of Science Progress
In Field, Laboratory
And Study
By Thomas r. Henry.

By Thomas r. Henry.
The pattern of a major drought,
comparable to those Of the summers of
1894 and 1896, now may be developing
over large areas of the United States
Following winter of exceptionally
heavy rainfall, the three months of
spring have piled up rainfall deficiency,
especially in much of the region be-
tween the Mississippi and the Rockies,
according to reports to DR.. ]. B. Kincer,
climatologist of the United States
Weather Bureau.
A week ago the trend to increasing
dryness was broken by heavy rains in
Iowa, Minnesota and the Dakotas, which
to some extent have relieved the fears
OF farmers and have made it possible for
seeds to sprout. But for March, April
and May the rain records have ranged
from half to two-thirds of normal over
much of the region.
1t is altogether too early to venture
even tentative predictions for the sum-
mer, DR.. Kincer says. Meteorologists are
worried, however, by the persistent ten
dency of weather to continue a pattern
which has once been set up.
Since the last great drought three
years ago great deal has been learned
about the fundamental factors at work
1t is now question of the relative posi-
tions of titanic masses of polar and
tropical air over the Plains States. But
these masses themselves tend to fall into
patterns remaining relatively fixed for
weeks at time, due to causes as yet
not understood.
The recent rains, Mr.. Kincer said, may
mean that break has occurred in this
pattern, or they may constitute only
temporary divergence. All things con-
sidered, the meteorologists are by no
means happy over the picture.
There are, however, encouraging fea-
lures, Mr.. Kincer pointed out Generous
winter rains-February was one of the
rainiest months in years for much of the
country-brought the farming areas into
the spring with fair supply of ground
water. The spring deficiency has no
where been quite SO severe as in the two
last drought years. The general pattern
does not seem to be so inflexible The
Western States are entering the period
of their normally greatest rainfall
June and July. There is no notable lack
Of moisture in the air, if conditions were
only right for squeezing it out in the
form of rain. The major trouble is that
the great air masses seem to be Stagnant
In order to have rain over the Great
Plains area. it is explained by Govern
ment meteorologists, the first require
| ment is that moistureladen air must be
! lifted to height where it can no longer
hold its water vapor. Generally such
| moist air comes northward from the
| Gulf of Mexico. When it reaches the
| Northwest it bumps into masses of cold
air from the Arctic over which it must
climb, if it has enough energy left after
| its long northward passage. The general
| pattern this spring, however, has been
| one of cold, dry air sinking rather than
warm, moist air rising. While such a
| condition continues there can be no
| heavy rains.
| Drought spots are developing in other
| parts of the country-notably the Vir-
! ginia Maryland area The dry weather
| has not continued long enough to do
very serious damage. A similar pattern
seems to be forming over the upper Ohio
Valley which hitherto has had bounti-
full supply of moisture.
| The agricultural prospects still are
highly problematical. Winter wheat has
! received a considerable setback in parts
of the Southwest, with the harvest close
at hand. The outlook for spring wheat
has been improved by the recent showers
at least, temporarily, Mr.. Kincer says
The Iowa corn crop is beginning to
show the effects of drought. In Iowa,
the observers report, stands are poor
and uneven, due in part to loss of the
seed to rodents.
Pastures and meadows need rain from
the Ohio Valley eastward, in Illinois, in
much of the northern and southern
Great Plains, in the Southwest and in
Oregon and Idaho. In some of these
districts deterioration has been con-
siderable.
Most of the cotton belt has had plen-
tiful rain and the crop seems to be in
an especially flourishing condition.