PHYSICAL OOEANOGBAPHY OF THE GULF OF MAINE 669 



Amount by which the air was warmer than surface water, April 6 to 20, 1920 



General locality 



Off Boston Harbor 



Off Gloucester 



Off Cape Ann _.. 



Off Ipswich Bay _.. 



Oil Isles of Shoals 



PlattsBani 



Near Cape Elizabeth 



Off Seguin Island 



Off Penobscot Bay 



Near Mount Desert Rock 



Near Mount Desert Island 



Northeast part of basin — 



Do 



Off Yarmouth, Nova Scotia 



German Bank 



Off Seal Island, Nova Scotia 



North Channel 



Browns Bank 



Eastern Channel 



East edge of Georges Bank 



Southeast slope of Georges Bank 

 East part of Georges Bank 



Do- 



Southeast part of basin 



Center of basin _— 



Near Cashes Ledge 



Basin off Cape Ann 



Off Cape Cod 



Do 



Cape Cod Bay. 



Mouth of Massachusetts Bay 



Station 



20089 

 20090 

 20091 

 20092 

 20093 

 20094 

 20096 

 20096 

 20097 

 20098 

 20099 

 20100 

 20101 

 20102 

 20103 

 20104 

 20105 

 20106 

 20107 

 20108 

 20109 

 20110 

 20111 

 20112 

 20113 

 20114 

 20115 

 20116 

 20117 

 20118 

 20119 



Date 



Apr. 6 

 Apr. 9 

 ...do.... 



...do. 



...do.... 

 Apr. 10 

 ...do .... 

 ...do .... 



...do 



Apr. 11 

 Apr. 12 

 ...do.... 

 ...do.... 

 Apr. 13 

 Apr. 15 

 ...do .... 

 ...do.... 

 Apr. 16 

 ...do.... 

 ...do.... 



...do . 



...do.-.. 

 Apr. 17 

 ...do.... 

 ...do.... 

 ..-do.... 

 Apr. 18 

 ...do-... 

 ..-do.... 

 Apr. 20 

 ...do.... 



Time 



3 p. m 



10.15 a. m. 

 1.60 p.m.. 



5 p. m 



10.30 p. m. 



3 a. m 



8 a. m 



12.20 p. m. 



11 p. m 



4p.m 



1 p. m 



4.30 p. m. . 

 9.30 p. m.. 

 2.15 a. m. . 



1 p. m 



6p. m 



9.15 p.m.. 

 12.20 a. m. 

 4.35 a. m. . 

 8.50 a. m. . 



5 p. m 



8.30 p. m.. 

 1.15 a. m. , 

 5.35 a. m. . 



1 p. m 



8p. m 



3.40 p. m.. 

 9.55 a. m. . 



1 p. m 



10.50 a. m. 

 8.20 p. m.. 



Amount 



by which 



air was 



warmer 



than 



water, 



°C. 



6.6 

 1.0 

 6.7 

 2.6 



.8 

 1.1 

 1.9 

 9.4 

 1.0 

 3.6 

 6.3 

 3.9 

 3.5 

 3.9 

 6.7 

 4.7 

 4.1 

 3.6 

 5.5 

 6.4 

 5.8 

 6.1 

 3.6 



.7 

 3.8 

 3.3 

 2.0 

 3.0 

 4.6 

 8.3 

 6.9 



The air averaged about 5° warmer than the water in Massachusetts Bay, along 

 Cape Cod, and out across Georges Bank to the continental edge by May 16 to 17, 

 1920 (run from station 20123 to station 20129), with the difference greatest (10°) 

 in Massachusetts Bay from 10 a. m. to 1 p. m., least (1.4°) at 9 p. m., but increas- 

 ing again to 4° to 5.5° over Georges Bank during the daylight hours of the next day. 



In any partially inclosed body of water, such as the Gulf of Maine, where the 

 wind may blow either out from the land over the water or in from the open sea, the 

 relation of water to air temperature depends largely on the strength and direction 

 of the wind at any particular moment. For instance, the Halcyon recorded an air 

 temperature of 23.3° C. and surface reading of 14.44° while fishing on Platts Bank 

 on July 27, 1924, at 5 a. m. in a fiat calm; but shortly afterward a breeze coming in 

 from the south— from the open sea — lowered the temperature of the air to 15.6°, with 

 no change in the water. On the whole, however, the difference between air and water 

 during the part of the year when the air is the warmer certainly rules greatest by 

 day, when the sun's heat pours down, and least by night. For instance, the air was 

 3° to 4° warmer than the water from 7 a. m. to 5 p. m. on the run out to the basin 

 off Cape Ann on July 15 to 16, 1912, and only about 1.5° to 2° warmer than the 

 water from 9 p. m. to 1 a. m. 

 37755—27 11 



