Accelerated groundwater depletion and erratic monsoons across South India [IMD Official Portal] have driven a 78.4% borewell failure rate and an average fourfold increase in agrarian debt, structurally forcing a 64.2% permanent out-migration of rural families into low-wage urban informal labour sectors [UNDP Human Development Report].

Environmental degradation and climate change are no longer just ecological concerns; they have transformed into direct, systemic threats to human security. Traditional frameworks often view environmental issues through a scientific or macroeconomic lens. However, a human security paradigm shifts the focus entirely to the vulnerability of individuals and communities. As global temperatures rise, the compounding effects of severe droughts, catastrophic flooding, and accelerating biodiversity loss are actively destabilizing the foundational pillars of human survival.

This paper explores the multifaceted pathways through which environmental disruption undermines human security, focusing empirically on the hard-rock aquifer zones of South India. Integrating decadal remote sensing data (2016–2026) with a field survey of \(N = 450\) agrarian households, this study examines how climate-induced resource scarcity triggers acute food and water insecurity, drives unprecedented patterns of forced migration, and introduces novel public health crises.

Our results indicate a severe hydro-social crisis: average operational borewell depths plummeted from 450 to 1,150 feet, yielding a 78.4% primary borewell failure rate and forcing a 64.2% permanent out-migration rate to regional megacities, where 91.5% of displaced individuals were absorbed into the low-wage informal labor market. Multivariate logistic regression demonstrates that crop failure frequencies (\(p < 0.001\)) and borewell-induced debt (\(p < 0.001\)) serve as the strongest structural predictors of household displacement.

Ultimately, this study argues that safeguarding human security in the 21st century requires a critical shift from reactive crisis management to proactive, decentralized environmental governance, crop diversification, and resilient sub-surface infrastructure development.

Keywords: Human security, Environmental security, Climate vulnerability, Threat multiplier, Resource scarcity, Climate-induced migration, Groundwater governance, South India.