What to know

• Human-caused global warming thinned glaciers and thawed mountain permafrost, likely helping to destabilize the Himalayan slope that collapsed last month and unleashed catastrophic flooding across Nepal, according to a report released Thursday.S1
• A 7.8 magnitude earthquake that hit the same mountain in 2015 could have played a role by weakening the underlying bedrock as well, but its precise impact is unclear.S2