THE RAINFALL OF GUERNSEY FOR THE 

 YEAR 1909. 



BY MR. A. COLLENETTE, F.C.S. 



The year 1908, as will be remembered, was the driest 

 year since 1870. Last year I prepared a table (IX. Trans. 

 for 1908) showing that the rainfall had reached a low figure in 

 the years 1858 and 1870 and that the two years, 1859 

 and 1871, following the driest years, were considerably 

 wetter ; in fact that they closed the dry period, or series 

 of dry years to which they belonged. This year, 1909, 

 has proved to be 7'78 inches wetter than last year and I 

 have reproduced the table (VII.), giving the fall in its place. 

 It will be seen that the rale applying to the last two very 

 dry periods applies also to the one we are passing through. 

 It will be noted that two very wet years, 1860 and 1872, 

 were immediately followed by wetter years, and therefore, 

 if there is a common cause for the dry periods, and if they 

 belong to any kind of cycle, 1910 should be a very wet year. 



1909 has given the same rainfall as 1907 and has been a 

 dry year for it closed with a deficit, as compared with the 

 67 years' average of 2*29 in. Last year's (1908) driest 

 month was June with a total of 0*62 in. This year (1909) 

 the driest month was May with 0.75 in. In 1908 two months 

 only, March and September, were over their averages. This 

 year (1909) there were three months with plus quantities, 

 these were March and October, and in a lesser degree June. 

 The month of June has the distinction of having given 

 the wettest week of the year, 3*31 in. having fallen between 

 the 1st and 7 th and inasmuch as the remainder of the month 

 yielded half an inch only it will he seen that June plus 

 quantity depended on the fill of that week. A reference 

 to Table V. will show that 2*53 in. fell on two days. If 

 we except that one week it will be seen that practically the 

 months April to September, inclusive were dry. January and 

 February were also dry — and in a lesser degree November 

 and December were also. 

 [1909.] 



