Changing Geo-Hydrological Regime Over the Changing Climate: Global North to Global South, A Case Study: Nelson River Delta, Canada, and Ganges Delta, India.

Deltas are globally considered as one of the most vital socio-ecological systems, however their geo-hydrological regimes are gradually destabilized by change in climatic patterns. Based on this scenario, the research delves into a comparative study of two contrasting deltas comprising of Nelson River Delta in Canada situated in Global North and the Ganga-Brahmaputra Delta spatially occupying India and Bangladesh situated in Global South. Both deltas are significant ecological systems; The Nelson delta is characterized by boreal-subarctic wetland ecosystems, fisheries and traditional livelihood, on the other hand, the Ganges Delta marks a region of high population density characterized by complex interplay of natural and anthropogenic activities, fisheries, intensive agriculture and mangrove ecosystems. Impact of climatic shifts are evident in both deltas. In the Nelson River basin, altered snowmelt regimes and river discharge, accelerated thawing of permafrost coupled with flow regulation are leading to alteration in sediment delivery, coastal stability and ice breaking processes. While, Ganga delta is subjected to intense monsoon variability, frequent cyclones, sea level rise are augmenting issues like salinity intrusion, sediment redistribution and subsidence. These fluctuations have reconfigured geo-hydrological hazards by escalating the frequency and magnitude of bank erosion, floods, wetland degradation and coastal retreat. The consequences extend surpassing the physical processes to extensive changes in life and livelihoods of the residents evident from shifts in fish productivity, agriculture, food security and infrastructure vulnerability. Ecosystem services comprising of storm protection, carbon storage, biodiversity support and freshwater provision are either being modified or lost in both the regions. The research emphasizes the requirement for climate-responsive, place-based planning that constitutes sediment management, nature-based solutions, hydrological restoration and community-centered governance. Establishing resilience in both Global North and South need inclusive, adaptive and ecosystem-oriented strategies that would address accelerating hydrological and climatic uncertainties.