302 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 70 



center of action may therefore be expected to have opposite effects 

 on the temperature to the east and west of the center. The tempera- 

 ture curves for Vladivostok (the inverted curve IX, fig. iii) and 

 for Barnaul (curve X) show that this is to a great extent the case. 

 These curves also show some agreement with the barometric curves 

 (I and II) for Batavia and Ponta Delgada, and with the other tem- 

 perature curves. As, however, there are such great changes in the 

 barometric conditions in inner Asia during the year, there being a 

 great minimum in the summer and a great maximum in the winter, 

 we cannot expect this agreement to be very close, and as will be 

 mentioned later, it is not only the changes in the horizontal circula- 

 tion of the atmosphere that are of importance for the thermal 

 fluctuations, especially not in the regions of pressure maxima in 

 higher latitudes. 



In figure 113 are given the temperature curves, smoothed by 

 twelve-month means, for eight stations in different regions of Siberia 

 and eastern Russia (east of the Ural). The values are departures 

 from normals computed for the thirty years 1877-1906. The fluc- 

 tuations demonstrated by the curves show a gradual transition from 

 the one region to the other, until the temperature fluctuations in 

 eastern Siberia, at Vladivostok (curve VIII), and less at Nerchinskii 

 (curve VII), go more or less in the opposite direction to those in 

 western Siberia and eastern Russia, at Barnaul, Ekaterinburg, 

 Nichne Tagilsk, and Bogoslovsk. 



It has, however, to be considered that the changes in temperature 

 at the earth's surface may not depend solely on the horizontal cir- 

 culation of the atmosphere, but also to some extent on its vertical 

 circulation. For instance, by a general increase of the atmospheric 

 circulation, there is a descending movement of the air, with an in- 

 crease of pressure, in the high-pressure regions, and an ascending 

 movement of the air, with a decrease of pressure, in the low-pres- 

 sure regions. According to the actual vertical distribution of tem- 

 perature in the atmosphere, these vertical movements should have 

 a tendency to raise the temperature in the high-pressure regions, 

 and to lower the temperature in the low-pressure regions, if it were 

 not for the effect of the horizontal air movements and also other 

 influences, in some regions, which may go in the opposite direction. 



The increase of pressure with descending air movements, in a 

 high-pressure region will, on the other hand, give relatively calm 

 weather with a clear sky. During the winter in the temperate and 

 cold regions, this will increase the radiation of heat from the earth, 



