442 Eighth Annual Report of the 



The Highlands or Plateaus of New York. 



The rate at which the average aniiiual temperature decreases 

 with altitude is usually given as 1 degree to 300 feet of elevation, 

 the rate being somewhat below this value in winter and above it 

 in summer. The rule is subject to considerable local variation, 

 however, and it was deemed best to make an approximate deter- 

 minaitiom foir this Stafte. Owing to the variety of local influences 

 which had also to be considered it was found necessary to make 

 a trial of various factors of reduction and draw iso'therms repre- 

 senting the results, accepting those which rediuced the effects of 

 altitude to a minimum. The rates of decrease in this case are 

 0.3 degrees per hundred feet of elevation for the winter and 0.4 

 per hundred feet for the summer, agreeing well with the usual 

 values. For the mountains of Northern New York however, a 

 factor much smaller than 0.3 decrees appears to hold for the 

 ^\^inter months; ibut the latter was adhered to throughout in 

 constructing the sea-level isotherms of plates 1 and 2. 



The highland districts of Central New York are substantially 

 alike in their temperature conditions, as these are shown by obser- 

 vation and also by the character and seasonal development of 

 vegetation, and hence only a general account of their cliimate is re- 

 quired. The Adirondack Plateau has some distinctive features 

 needing a separate statement. 



In computing the temperature normals of the eastern and west- 

 era plateaus, it was found that closer comparisons could be made 

 between Cooperstown (chosen as the standard of reference) and 

 nearly all other stations of the plateaus, than between the latter 

 and low level stations of the coast and lake regions. In fact^, the 

 thirty-eight year normal of Oooperstown may, without much error^ 

 be tiaken to represent tli(> temperaturi' of the plateaus at the alti- 

 tude of 1,000 to l,.WOi fec^ throughout the central portion of the 

 State. The western plateau shows, in winter, a slight excess of 

 temperature (about one degree) over that of the ea;stern region, 

 which may be attributed in part to the influence of the Great 

 Lakes, and in part to the gradual manner in which t.lie surface 



