Westerly induced precipitation increase drives near-surface ground ice gain on the Tibetan Plateau despite warming
- Yi Zhao
- Dongfeng Li
- Jan Nitzbon
- Zhuotong Nan
- Yuqi Song
- Xie Hu
- Youhua Ran
- Shang Tian
- Rui Deng
- Yingzhong Luo
- Yiyi Li
2026-07-23
Near-surface ground ice loss is a key sign of permafrost degradation under global warming, dictating ground destabilization and carbon feedback. However, recent field evidence suggests that ground ice may locally accumulate, while the driving mechanisms remain unclear. Leveraging borehole ground ice observations, a physics-based permafrost model, and satellite-based ground deformation data, we identify an anomalous ice increase at the active layer bottom despite climate warming across the interior Tibetan Plateau, occupying 35% of plateau’s permafrost area. Strengthened westerlies have enhanced precipitation, supplying additional soil moisture that refreezes at the active layer bottom and drives this unexpected ice gain. Freeze-thaw process associated with the accumulated ice amplifies ground deformation, destabilizing permafrost landscapes and threatening socioeconomic activities. This anomalous ice gain in permafrost regions, together with the Karakoram anomalous glacier mass increase, represents a divergent cryospheric ice gain against global ice loss under climate warming, highlighting that rapid precipitation increase may locally outweigh temperature in driving cryosphere evolution on the Tibetan Plateau.