Abstract:
This study investigated the multifractal characteristics of fne resolution (0.25o
x0.25°) daily
gridded rainfall felds of India over the period 1901–2013 to examine their spatiotemporal
variability. The scaling characterization using Multifractal Detrended Fluctuation Analysis (MFDFA) detected short-term persistency and strong multifractality in the majority of
rainfall (over 81%) of the grid points. A detailed exploration on the spatial variability of
multifractal properties such as Hurst exponent, spectral width, asymmetry index, Hölder
exponent are also performed for six rainfall homogenous regions and 34 meteorological
subdivisions in India. The results showed that the highest persistence and complexity is
noted in the mountainous terrains of northern and northeastern India. The sub-divisional
scale analysis showed that the variability of persistence and complexity is the highest in
Kerala and lowest at Vidarbha. Further, the evaluation of multifractal properties of rainfall series of pre- and post-1976/77 Pacifc climate shift showed an increase in strength of
multifractality in 62% grids after the shift. Changes in the status of persistence with respect
to 1976/77 is the highest at Uttaranchal subdivision and changes from positive to negative
asymmetry was the highest at northwestern (NW) region. Grid points of Peninsular India
exhibited least reduction in complexity, multifractality and persistence in the post-1977
period when compared to pre-1977 period.
