ARCTIC METEOROLOGY* 
By HERBERT G. DORSEY, Jr. 
Arctic Weather Central, Air Weather Service 
ARCTIC ATMOSPHERIC CIRCULATION STUDIES 
About a century ago theoretical considerations of the 
probable pressure distribution over the Arctic led to 
the postulation of a zonal system of westerly winds 
converging toward a center of low pressure at the North 
Pole. Shortly afterward an increasing amount of ex- 
pedition data revealed a trend toward higher pressures 
and relatively frequent easterlies north of the great 
oceanic storm belts. These new data enabled Teisserenc 
de Bort to identify the large-scale features of the 
pressure distribution as early as 1881. Concurrent 
studies of the probable radiative cooling over the ice- 
covered polar basin were summarized by Helmholtz in 
1888 in his first paper on atmospheric motion, in which 
he indicated that the relatively high pressure at sea 
level should be replaced by a low-pressure system aloft. 
During this period the role of polar air in the origin of 
storms was being investigated. A successful culmination 
to many important contributions was achieved in 1922 
by J. Bjerknes and H. Solberg with their paper, ‘The 
Life Cycle of Cyclones and the Polar Front Theory 
of Atmospheric Circulation.” 
Perhaps worthy of brief comment at this point is the 
thought that possibly Bjerknes and Solberg’s funda- 
mental statement of modern meteorological principles 
in that paper was assumed by some glaciologists to be an 
attack on the ‘Glacial Anticyclones” of Professor 
Wilham H. Hobbs. His theories, giving Greenland’s 
“Glacial Anticyclones” a dominant role in the general 
circulation, were first published in 1910 [8] and have 
been rigidly reiterated up to now [10] despite a steady 
increase in adverse meteorological evidence! IS, ili, 
Following the discussions appearing in Problems of 
Polar Research, compiled and published by the Ameri- 
can Geographical Society in 1928, one of the earliest 
and most detailed studies to appear on weather condi- 
tions in the Arctic was that by Baur [1], presenting 
results in the form of monthly average charts for 
various elements, including temperature, cloudiness, 
and pressure. Baur showed in 1929 that the polar 
maximum of pressure was closely related to minimum 
temperature regions, and traced its movement from 
eastern Siberia in winter to a position north of the 
Arctic Archipelago in spring when the subarctic con- 
tinental regions became relatively warm, with a con- 
tinued eastward movement toward northeast Greenland 
and Spitsbergen in early summer. The decreasing cen- 
tral pressure was down to about 1014 mb at the summer 
minimum. In early autumn the Canadian Arctic Archi- 
* Submitted with the permission of the Air Weather Service. 
Conclusions and opinions are those of the author. 
1. For an appraisal of the controversy over this point see 
“Some Climatological Problems of the Arctic and Sub-Arctic”’ 
by F. K. Hare, pp. 952-964 in this Compendium. 
pelago and the adjoining polar pack ice cool rapidly 
to attain a secondary maximum in the annual pressure 
trend, but this is soon exceeded by the Siberian anti- 
cyclone and its weaker counterpart over the Yukon 
Territory. Baur’s charts, obtained from station pressures 
and corrected for large-scale anomalies presumably pres- 
ent in some of the shorter records, lose little in com- 
parison with the indications of modern data. 
The theoretical basis for much subsequent research 
on the heat balance of the earth and the general circula- 
tion of its atmosphere was published by V. Bjerknes 
in 1933 [2]. In the same year, Shaw [18] included in his 
comprehensive Manual of Meteorology charts of sea- 
level normal pressure and upper-air normal pressure 
charts (partially from earlier work of Teisserence de 
Bort) for heights up to 8 km. However, Shaw’s charts 
were not intended to be relied upon over the north polar 
region. The next sea-level pressure charts to be prepared 
for the Arctic were those resulting from the joint studies 
of Sverdrup, Petersen, and Loewe, published in the 
K6ppen-Geiger Handbuch der Klimatologie in 1935 [19]. 
Their pressure patterns were quite similar to those of 
Baur. 
Upper-air research conducted by the U. S. Weather 
Bureau was temporarily concentrated on a revision 
of Shaw’s 2- and 4-km charts, after Wexler [23] m- 
vestigated the formation of polar anticyclones. Many 
new data were available, and the final charts by Byers 
and Starr for January [4] gave the first definite indica- 
tion that the elongated cireumpolar vortex had separate 
closed centers, one over northeastern Siberia and the 
other over northern Hudson Bay. Subsequently, Namias 
and Smith [13] prepared monthly normal charts for the 
10,000-ft level, then converted these to 700-mb con- 
tours. Revisions are made by Namias whenever new 
data suggest possible improvements in the work of the 
Extended Forecast Section, U.S. Weather Bureau. 
In the great amount of theoretical research on the 
general circulation drawn upon by Rossby to obtam 
his schematic model of 1941 [15], and in later work, 
the north polar region has not been neglected. The 
principal results contributing to arctic meteorology are 
those pertaining to displacements of the principal cen- 
ters of action. Appropriate reference will be made to 
some extended-range forecasting principles derived by 
Willett [24] which have significant value for arctic 
operational planning purposes. A recent contribution 
by Rossby [16] discusses the release of potential energy 
involved in the southward displacement of anticyclonic 
cold domes from high latitudes. 
A 1946 publication of the U. 8. Weather Bureau [20] 
contains monthly normal sea-level pressure maps for 
the Northern Hemisphere. These normals, computed 
from the noteworthy 40-yr series of daily synoptic 
charts, are no better over the polar basin than are the 
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