The Impact of Climate Change on Groundwater Level decline: A Fractional Variable-Order Model

Groundwater is a critical component of the Earth's freshwater resources, constituting approximately 30% of the world's freshwater supply. It is stored in aquifers and is indispensable for a variety of human purposes, such as agriculture, potable water supplies, and industrial operations. Groundwater declination has profound implications, including water scarcity, land subsidence, deteriorating water quality, and the disruption of ecosystems dependent on stable water tables. This paper proposes a nonlinear fractional variable-order model of groundwater declination in the sense of Liouville-Caputo(LC), Caputo-Fabrizio(CF) and Atangana –Baleanu (AB) fractional derivatives. The existence and uniqueness of fractional solutions has been established and numerical simulations have been carried out to illustrate the impact of pollution, deforestation, frequent pumping of water and evaporation on the groundwater level.