Nepal, Aug. 6 -- The monsoon is back, bringing another series of disasters. According to the Department of Roads, five major highways are completely blocked across Nepal this week, with dozens of other road sections partially disrupted. The BP Highway connecting Kavrepalanchok and Sindhuli, a critical chokepoint linking eastern Nepal to the capital, is barely passable. Farmers in the Terai are anxious as the rain arrives late, leaving the soil harder for the next yield. One thing that remains common across these disasters is that there is no track record of data.

A few weeks ago, I was standing on the flooded bank of the Nakhu Khola in South Lalitpur with climate scientists from across the Hindu Kush Himalaya, including glaciologists, hy...