Enhanced runoff over the Three-River Source Region in China after 2000: Distinct response to recent global warming

This is the authors' abstract. We don't add key points for this paper.

The runoff over the Three-River Source Region exhibits decreasing and increasing trends during 1980–1999 (P1) and 2000–2019 (P2), respectively, showing a distinct response to global warming after 2000. Based on station and atmospheric reanalysis data, we explore the dominant mode of runoff and investigate the distinct response to global warming via moisture budget analysis and linear trends. Results show the increased runoff during P2 is mainly contributed by the enhanced rainfall in June–September. One source of increased rainfall is closely related to the enhanced upstream westerly moisture transportation, driven by a reversal of the thermal gradient over the Tibetan Plateau featuring a warm-north/cold-south regime in P1 and warm-south/cold-north pattern in P2. Another source is the enhanced southwesterly moisture supply due to Indian Ocean warming. The increased runoff is significant over the Yellow River source, showing a benefit of water resource due to the significant warming in the Indian Ocean after 2000.