ON THE SEASONAL VARIATIONS OF TEMPERATURE. 



469 



from the North Sea prevents sun-heat from raising the surface tempera- 

 ture more than 0°1 C. in the warm months, and allows no rise of tem- 

 perature at all in the cold months. It is probable that the effect is pro- 

 duced by the warming power of the ebb-water at 'J a.m. making up for 

 loss by radiation at night, and this would completely account for the 

 range being greater at the bottom than on the sui'face, as the surface is 

 naturally more affected by the fresher ebb-water. 



North Garr Light-vessel. Mean Tidal Effect on Temperature. 



December 



January 



February 



March . 



April . 



May . 



June . 



July 



August 



September 



October 



November 



December 



January 



February 



March . 



Year High 

 Water 

 I A.M. 



1 S, 



18S9 

 1890 



10-6 

 U-7 

 11-7 

 l.S-U 

 11-3 



Low 



Water o o 

 3 p.m. ^--^° 

 S3 



°C. 

 7-0 

 6-2 

 6-4 

 5-7 

 6-8 

 9-9 

 10-5 

 12-4 

 12-8 

 13-3 

 11-5 

 9-3 

 7-3 



Low 



Water 



A.M. 



High 



Water „ „ 

 3 r.M. °»"*= 

 S3 



10-6 

 11-5 

 12-0 



12-e 

 11-1 



8-9 



10-0 

 12-1 

 12-3 

 12-9 

 11-1 

 8-7 



-0-6 

 0-6 

 0-3 

 0-3 

 0-0 

 -0-2 

 -0-6 

 0-1 

 0-1 

 0-1 



High I Low ] 1 Low 



Water'Wateri -r, p Water 

 9 a.m. l3r.M. i^^~^-',aA.M 

 B., B3 I i B, 



61 



7-4 

 9-0 

 10-7 

 11-8 

 12-4 

 11-4 

 8-7 



11-7 

 12-6 

 11-G 



High 



Water 



3 P.M. 



B 



U-1 

 11-9 

 13-0 

 11-3 

 9-0 

 7-3 

 5-6 



