176 



THE CLIMATE OF CALVERT COUNTY 



in the report on the Climate and Weather of Baltimore and Vicinity.^ 

 The monthly average temperature of the water in the harbor, and of the 

 air above it, is reproduced here in Table II, and for comparison the mean 

 temperature of the waters of the north Atlantic about Lat. 35° N., and 

 Long. 0° to 50° W. 



TABLE IL 



Tempeeatdee of the Wateu in Baltimore Haeboe, of the Aie, and of the Sueface 



OF THE Atlantic, Lat. 35 N. 



The temperature of the water in Baltimore harbor is lower than tlie 

 temperature of the overlying air excejDt in late autumn, when the tem- 

 perature of the land is falling more rapidly than the temperature of the 

 water, while in the ocean eastward in the same latitude the water is 

 always warmer than the air. The greatest difference is found during 

 spring and early summer; during April, May, and June, the water is 

 nearly 6° colder than the air, and it is least in winter when the dif- 

 ference nearly vanishes. The effect of the water in lessening extremes 

 of temperature near the coast in summer is much diminished in conse- 

 quence of the fact that Avarm ^^eriods are usually associated with a stag- 

 nant atmosphere (very light winds) due to the encroachment of the per- 

 manent high pressure area about Lat. 30° on the southeast coast of the 

 United States; so it is found that even in Calvert County high summer 

 temperatures sometimes exceeding 100° are recorded. 



^Report on The Climate and Weather of Baltimore and Vicinity; by Dr. 

 Oliver L. Fassig, vol. ii, part la, page 146. The temperature of the water 

 was taken at 2 p. m. when it is normally a little cooler than the air (see 

 Table I) but the departures in this case are so great as to substantiate the 

 •conclusion in the text that the harbor waters are abnormally cold. No 

 doubt the mean temperature of the water from tridaily observations would 

 prove to be higher than the temperature of the air during October, November. 

 December, and January. 



