444 Eighth Annual Eeport of the 



is lost at night by the flow of cold air down the slopes. Thus the 

 mean temperatures of Binghamton, Waverly, Elmira and Addison, 

 in the main branches of the Susquehanna valley, are but little 

 over a degree lower than those of the Central Lake region, although 

 the difference is greater in the spring and fall, owing to the retard- 

 ing influences of the lakes. 



No statement can be made here as to the climate of the Catskill 

 mountain region, owing to the lack of any adequate data. 



The Adirondack Plateau is subject mainly to the same influences 

 which determine the climate of the St. Lawrence valley, excei>ting 

 that the central and eaisitem portions of the highlands are not 

 reached by the lake winds. A very broken and heavily timbered 

 surface offers great obstmctions to the circulation of air currents, 

 and hence the summer temperature, although the lowest in the 

 State, is (siomewhat higher than would otherwise be, due to the 

 elevation of the region. 



The normals given in the general table can not be considered 

 to be fully established^ depending as they do upon a few brief 

 series of observatioms. If even approximately correct^ however, 

 they represent a true anomaly of temperature during the winter, 

 Eiince the average values at some of the mountain stations are 

 then higher than those recorded at stations of the Sit. Lawrence 

 Valley, more fthan a thousiand feet below. In order to investi- 

 gate more fully the existence of such a condition, several date^ 

 were selected when the region was subject to anticyclonic areas 

 and their accompanying cold waves. An inversion of tempera- 

 ture was found to exist in a considerable number of cases, but 

 most decidedly on December 8, 1800. The isotherms of the ac- 

 companjing chart represent the average temperatures for that 

 day in northern New York, as reduced to sea level by applying 

 the factor 0.3 degrees for each 100 feet of elevation of the 

 various statioais, the accompanying figures showing the actual 

 (unreduced) temperature at each station. Keene Valley, whose 

 temperature ( — 6.5 degrees) was the lowest of the series, is 

 located at the bottom of a dfeep mountain valley or goi'ge in a 

 position to receive the downfall of oold surface air from a large 



