Trend and Seasonal Analysis of Annual One Day Maximum Rainfall

PA PANDYA; D K DWIVEDI; BIMAL PRACHI; SHIMVAM AHIRWAR; NAITA KUMARI

doi:10.21921/jas.v9i03.11014

PA PANDYA College of Agricultural Engineering and Technology, Junagadh Agricultural University, Junagadh, Gujarat, India
D K DWIVEDI Deptt. of Agricultural Engineering, Faculty of Agriculture, Sri Sri University, Cuttack, Odisha, India
BIMAL PRACHI College of Agricultural Engineering and Technology, Junagadh Agricultural University, Junagadh, Gujarat, India
SHIMVAM AHIRWAR College of Agricultural Engineering and Technology, Junagadh Agricultural University, Junagadh, Gujarat, India
NAITA KUMARI College of Agricultural Engineering and Technology, Junagadh Agricultural University, Junagadh, Gujarat, India

DOI: https://doi.org/10.21921/jas.v9i03.11014

Keywords: Trend analysis, Mann-Kendall's test, Rainfall, Sen's slope, Seasonality , Saurashtra

Abstract

Saurashtra region is characterized by high temporal and spatial rainfall fluctuations. The daily maximum rainfall has a direct impact on the agricultural yield. It is thereby necessary to comprehend the trend changes in the annual daily maximum rainfall (ADMR). The daily rainfall data of 40 years (1981 to 2020), for 11 stations in Saurashtra was utilized for trend analysis of ADMRusing Mann Kendall's method and Sen's slope method. It was revealed from the Mann-Kendall test that significant positive trends were exhibited at Dwarka and Surendranagar. Further, Sen's slope and linear regression indicated that the ADMRat Rajkot and Surendranagar were having highest increasing trend. Trend analysis of ADMRcontribution to annual rainfall showed negative trend indicating better temporal distribution of rainfall. It was also revealed that the extreme events of rainfall usually occurred uniformly on certain days of the year from the results of directional statistics.