TATOPANI, Nepal - Legendary Sherpa mountaineer Apa is warning that more flooding tragedies like the one that wiped out his potato farm 26 years ago may be coming as Himalayan glaciers melt.

He is on a 120-day trek across Nepal to tell villagers about the danger of more devastating flash floods as climate change melts glaciers and fills high-altitude lakes to the bursting point.

Apa lost his possessions in the 1985 flood that killed five of his neighbours, but he restarted his life as a trekking guide. He has since scaled Everest a record 21 times.

He now sees the trekking industry as the region's best hope, as trails must be built for growing numbers of tourists and for scientists to reach glaciers and assess flood threats.