PROJECT TITLE :

Irrigation Impacts on Scaling Properties of Soil Moisture and the Calibration of a Multifractal Downscaling Model

ABSTRACT:

Irrigation is an anthropogenic issue which will introduce significant spatial heterogeneity within the distributions of soil moisture $(theta)$ and potentially affect the performance of downscaling models of coarse satellite products. During this paper, we have a tendency to propose a framework to: one) quantitatively analyze and compare the size invariance and multifractal properties of $theta$ within the presence of irrigation; and 2) filter out the effect of irrigated croplands in the applying of a multifractal downscaling algorithm primarily based on the hypothesis of spatial homogeneity. For this aim, we tend to use the $theta$ data sets of the National Airborne Field Experiments 2005 (NAFE05) and 2006 (NAFE06) campaigns in Australia. Results show that irrigation affects the dimensions-invariance properties (tested from 32 to one km) in a very massive high-density agricultural district within the semi-arid NAFE06 web site, though it will not have a significant impact on the sparser agricultural districts of the temperate NAFE05 region. The multifractal downscaling model was calibrated using a strategy that attenuates the impact of irrigation on $theta$ fields, so mimicking natural settings. Performances, tested against aircraft and, for the primary time, ground-based observations, are adequate in most cases. Some deficiencies are found for drier conditions in regions with the next proportion of irrigated fields, suggesting the necessity to more refine the techniques for detecting irrigated croplands. Overall, the findings of this work reveal that the impact of irrigation on the soil moisture statistical variability and downscaling is larger in drier regions or conditions, where irrigation creates a drastic distinction with the surrounding areas.