Nepal's flood warning gap: What remote sensing can fix and what it cannot

A rock and ice collapse above Langtang Lirung triggered a flash flood on August 26 that has killed more than 1,400 people in Nepal, left over 6,000 missing, and caused an estimated $2.6 billion in damage, figures still under revision as search operations continue. The debris travelled down the valley at approximately 190 kilometers per hour, and Nepal's existing warning system, satellite coverage, and international support each had a specific limitation that morning, detailed below. Prime Minister Balendra Shah is scheduled to address the UN General Assembly on September 24.

ON THE MORNING OF AUGUST 26