| 17 Feb 2026
A Systemic Shift towards Hydroclimatic Whiplash in India: Event-Based Evidence of Escalating Dry-Wet Transitions since 1951
Abstract. This study presents a comprehensive assessment of the evolution of hydroclimatic extremes, dry spells (DS), wet spells (WS), and their rapid transitions (whiplash) across India from 1951 till 2019. A marked reorganization of extremes emerged around the 1980s regime shift, characterized by widespread intensification of WS and a 40 % rise in DS-affected grids experiencing fewer but longer events. Using Event Coincidence Analysis, trigger relationships between extreme DS and WS are quantified, revealing that trigger coincidence rates exceeded 0.8 after the mid-1980s and increased spatially by nearly 49 % over the west coast, Central India, and the Northeast. Disaggregating transitions demonstrated an emerging dominance of dry-to-wet (DTW) behavior, with an increase of ~14 %, reflecting reorganized monsoon feedbacks. Quantification of whiplash severity revealed a 13 % and 8.7 % rise in extreme and severe whiplash frequencies and a 26.6 % increase in grids exhibiting simultaneous high frequency, duration, and intensity. Spatially, the southwest coast and northern India exhibit ‘persistently high’ risk with no recovery since 1951, while the east coast and central India show ‘emerging’ volatility. Crucially, this intensification translates into a quantifiable ‘climate penalty’ on agriculture: post-2000 wheat yields show persistent negative anomalies with an increase in exposure to extreme whiplash risk, which in turn demands an immediate pivot in adaptation and resource planning.
I have read the manuscript and appreciate the authors' excellent work. I found the work technically sound with a few moderate comments, which the authors may think of addressing:
1. What is the role of intraseasonal oscillations and their changes on the conclusions derived by the authors? Are there changes on the 10-20 day and 30-60 day scales that are responsible for the authors' findings?
2. I would love to see authors' comments on the spatial structures of the patterns, for what are the scales of the changes, over small regions, or large regions or both? What about the spatial coherence? Maybe some discussion would be useful.
3. Impacts on agriculture are good extension, but how are the authors making sure that other policy and socio-economic factors are also being considered in their analysis? If not considered, a line specifying this as a limitation would be good.