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The analysis of the Fainfall data (1961-1999 of Faisalabad revealed decreasing trend upto 1970, whereas increasing trend was aftenkards. The ciontrituticn to this in tend( ney 1970 was mainly matte by summer rainfall.
INTRODUCTION
T1i 6ource of all fred-i. water on the earth is precipitation in the form of sncw, lu frost and rli w. Variations of precipitation in time and space are u-; e yin to these livirg in areas- were precipitatio-n is fairly evenly dis-tuilnited tiiroupliglut the 1,%.ar aril does not vary greatly from place to place. How ev(r, this vilriability of precipitation from the coastal area to tho interior, tma frt.im winter to L,,,unitner i ubviout fact which to a large extent deternii-n( One 1.11.4.1 social activities.. kVhile portions of a precipitation record may suggest an increasing or ilecr(aning trcr.d, there is usually a tendency to return to the mean: abnormally \vet tu.(1. to be balanced h3r. dry periods. The regularity of thet;e fluctuations bas been repeatedly investigated,. More than 100 apparent cycles, ranving it per ua frvm 1 to 744 years have been reported by Shaw (1942). However, -with the exception of dil rnal. and seasonal variations, no persistent cvel; Hi' any appr( .ciable magnitude have been conclusively demonstrated
(LantIslwrg, 1945). Lc rainfall data analysed. by Dyer (1077) to trace the periodicitie;...i. that if the regional to series were smoothed out and it was Eist4nlit.ki Chat the past vat terns in these series continued. to repeat themsplves, subit.ctivt. forcea,sts for the genural behaviour of rainfall could be made.
MATERIAI,S ANT) MF,ITHODS -the data used in the present study have been recorded at the Meteorolo-gical pry Faisalabad.
*1)epartmeut of Physics and Meteorology, University of Agriculture. Faisalabad;
M. A Salimi , N. A. Parwaz. (1984) Rainfall trends and cyclic variations at Faisalabad, Pakistan Journal of Agricultural Sciences, Volume 21, Issue 1,2.
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