Geography – Global water resources | e-Consult

Natural processes are fundamental to the replenishment and maintenance of freshwater resources. The water cycle, driven by solar energy, is the primary mechanism for moving water between the atmosphere, land, and oceans. Precipitation (rain, snow, sleet, hail) is the most direct source of freshwater replenishment, directly feeding rivers, lakes, and groundwater aquifers. Groundwater recharge occurs when precipitation infiltrates the ground and replenishes aquifers. Evaporation from oceans, lakes, and soil contributes to atmospheric moisture and rainfall.

Human activities can significantly disrupt these natural processes. Deforestation reduces evapotranspiration, leading to decreased rainfall and increased surface runoff. Urbanization increases impermeable surfaces, reducing groundwater recharge and increasing flood risk. Agricultural practices, such as excessive irrigation, can deplete groundwater aquifers and alter local water cycles. Pollution from industrial and agricultural sources can contaminate water sources, reducing their availability for human use and impacting ecosystem health. Climate change, driven by human emissions of greenhouse gases, is altering precipitation patterns, leading to more extreme events like droughts and floods, and impacting the stability of water resources. These disruptions highlight the need for sustainable water management practices that minimize human impact on natural water cycles.