Climate change is leading to conditions that can destabilise high-mountain rock and ice, strengthening prospects for disasters such as this week’s Himalayan flood along the border between Nepal and China’s Tibet that killed 165, scientists say.

At least 800 foreigners are among the nearly 1,500 missing, authorities said on Thursday, a day after a massive wall of mud and rock collapsed into a Himalayan river, sending catastrophic floods through towns and valleys.

“Climate change is generating conditions that can destabilise high-mountain rock and ice," said Simon Cox, chief scientist at the Mountains to Sea programme at Earth Sciences New Zealand.

That in turn makes collapses and cascading hazards of the kind seen this week more frequent, he added.

While the exact cause of Wednesday’s disaster is still being analysed, scientists say it probably began with a massive ice-rock avalanche on the northern slo...