The Cold War Roots of Global Warming - Behind the Curve - page 8

always been simple. “Weather,” says the Oxford English Dictionary, refers to
“the condition of the atmosphere (at a given place and time) with respect
to heat or cold, quantity of sunshine, presence or absence of rain, hail,
snow, thunder, fog, etc., violence or gentleness of the winds.” 27 The char-
acteristic weather conditions of a country or region over time, in turn,
constitute that region's “climate.” 28 As Paul Edwards explains in his history
of computer-based climate modeling, A Vast Machine, however, until the
1950s the prime objectives and most important problems of climatology and
meteorology were very different. Meteorologists have almost always sought
primarily to provide a more accurate and reliable prediction of the weather,
and in the early twentieth century, forecasting involved as much art as it
did science. Weather forecasters— mostly amateurs— typically relied on
local knowledge and local records to help them predict relatively small,
short-term changes in local conditions for practical purposes. Climatolo-
gists, on the other hand, focused predominantly on reconstructing past
climates and on using universal geophysical principles to try to explain
long-term changes in those climates. Climatologists were, by and large,
professional scientists working in university departments of geology or
geography, and their work had few immediate practical applications.
This began to change in the 1950s, and it is helpful to approach the his-
tory of climate modeling with a brief history of meteorology in mind. As
a scientific discipline, meteorology was relatively late to professionalize,
but when this process finally began in the 1930s, the field and its methodol-
ogy changed rapidly. Impetus for expanding American meteorology came
from many quarters, including the American Meteorological Society, the
Weather Bureau, the U.S. Navy, and the nascent American airline indus-
try. The science, however, came primarily from Sweden. In the early twen-
tieth century, a group of scientists studying under Vilhelm Bjerknes and
his son, Jacob, in Bergen, Sweden, began to address weather phenomena
in physical terms. They focused not just on traditional “weather types”
and conditions on the ground but also on the movements of large masses
of air and ocean that drove cyclones, storms, and, ultimately, just about
every weather event under the sun. Their approach came to be known as
dynamic meteorology. 29 In the late 1920s and 1930s, many of these “Bergen
school” scientists began to appear as visiting scholars in the United States,
and their work laid the foundation for the professionalization of American
meteorology.