The "Asian Water Towers" (AWTs), a high-altitude region with a mean elevation exceeding 4,000 meters, serve as the primary freshwater source for nearly 2 billion people. While the Indian summer monsoon is well known for shaping seasonal rainfall patterns that help feed the AWTs, the hydrological rol e of the mid-latitude westerlies—which dominate regional weather patterns for three-quarters of the year—has been unclear. ...read more read less