- 1Indian Institute of Technology BHU (Varanasi, India), Indian Institute of Technology BHU (Varanasi, India), CIVIL ENGINEERING, India (abhimanyuverma.rs.civ23@itbhu.ac.in)
- 2Indian Institute of Technology BHU (Varanasi, India), Indian Institute of Technology BHU (Varanasi, India), CIVIL ENGINEERING, India(kkp.civ@itbhu.ac.in)
- 3Indian Institute of Technology BHU (Varanasi, India), Indian Institute of Technology BHU (Varanasi, India), CIVIL ENGINEERING, India(skumar.civ@itbhu.ac.in)
Abstract
Understanding the spatio-temporal evolution of compound hydro-climatic extremes is critical for assessing climate-related risks in monsoon-dominated river basins. This study examines long-term changes in rainfall and temperature extremes across the Damodar River Basin, India, using station-based extreme climate indices derived from daily observations. Fifteen meteorological stations representing diverse physiographic and climatic conditions within the basin were analyzed to capture spatial variability and temporal evolution of hydro-climatic extremes.
A comprehensive suite of rainfall-based indices (CDD, CWD, PRCPTOT, R10mm, R20mm, R95p, R99p, RX1day, RX5day, and SDII) and temperature-based indices (TNn, TNx, TXn, TXx, and DTR) was employed to characterize changes in the frequency, intensity, and persistence of extreme events. Monotonic trends in individual indices were assessed using the non-parametric Mann–Kendall test, while Sen’s slope estimator was applied to quantify the magnitude of change. Statistical significance was evaluated at the 95% confidence level, ensuring robustness against non-normality, outliers, and data heterogeneity commonly associated with hydro-climatic time series.
To investigate compound behavior, rainfall and temperature extremes were jointly interpreted within the framework of hot–wet, hot–dry, and wet–cold event combinations. Station-wise comparisons of trend direction and magnitude were used to identify spatial patterns and emerging hotspots of compound hydro-climatic extremes across the basin. The results reveal pronounced upstream–downstream contrasts and substantial regional heterogeneity in the evolution of compound extremes, reflecting the combined influence of monsoon dynamics, topographic variability, and local climatic conditions.
The proposed framework offers a systematic and data-efficient approach for analyzing the spatio-temporal evolution of compound hydro-climatic extremes using observed climate indices. The findings provide valuable insights for basin-scale climate risk assessment and support informed decision-making related to water resources management, infrastructure resilience, and disaster risk reduction in monsoon-affected river basins.
Keywords
Compound hydro-climatic extremes; Extreme climate indices; Trend analysis; Spatio-temporal variability; Damodar River Basin.
How to cite: Verma, A., Pandey, K. K., and Kumar, S.: Spatio-Temporal Evolution of Compound Hydro-Climatic Extremes in a Monsoon-Dominated River Basin in India, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-16376, https://doi.org/10.5194/egusphere-egu26-16376, 2026.
