1914-15.] Meteorological See-Saw over Antarctic Seas. 
203 
XX.— On a See-Saw of Barometric Pressure, Temperature, and 
Wind Velocity between the Weddell Sea and the Ross Sea. 
By R, 0. Mossman. 
(MS. received May 28, 1915. Read June 28, 1915.) 
In the course of a large inquiry on the inter-relations between the meteoro- 
logical conditions in Antarctica and the Southern Ocean, on the one hand, 
and those prevailing in the southern continents, more especially South 
America, on the other, there has come to light an interesting see-saw between 
the barometric pressure, air temperature, and wind velocity in the Weddell 
and the Ross Seas. The above inquiry, which I hope to lay before this 
Society shortly, refers to the eight-year period 1902-09 ; and since 
the present paper deals with the years 1902, 1903, 1911, and 1912, 
I have thought it better to make it the subject of a separate communica- 
tion. The positions of these stations and others where observations have 
been made are shown on the accompanying map, for which I am indebted 
to Dr H. R. Mill. The figures within the rings give the number of years 
covered by the records at the various places. 
The data for the Ross Sea are derived from Scott’s two expeditions * 
which wintered in M‘Murdo Sound, and those for the Weddell Sea are 
based on the observations initiated by the Scottish National Antarctic 
Expedition at Laurie Island, South Orkneys, and carried on since February 
1904 under the direction of the Argentine Meteorological Office. As the 
observations at the South Orkneys did not begin tiil March 1903, the data 
available from the neighbouring station occupied by the Nordenskjold 
Expedition at Snow Hill, Graham’s Land, have been laid under contribution. 
Fortunately the two series overlap during eight months, and it has thus 
been possible to interpolate values by differential methods, and fill in the 
deficiencies that exist for the period March 1902 to March 1903 covered 
by the M‘Murdo Sound observations. 
This applies to temperature and wind data, the mean monthly pressures 
during the above period having been measured off* the monthly isobaric 
charts given in the Meteorologischer Atlas, Deutsche Sildpolar Exioedition, 
1901-03, by Drs Meinardus and Mecking.]- The following are the posi- 
* The data derived from Shackleton’s Expedition of 1908-09 are not yet available, 
except provisional temperature means, 
t Berlin, 1911. 
