Solution: Thick cloud above a peak - NYT Crossword

Last seen in the Times puzzle in 1981, VOLCANIC ASH is an interesting phenomenon — minerals churned out of the Earth’s crust that can enrich soil so intensively that people will risk living near a volcano for harvests. Notice that INDONESIA is “living” fairly close to the base of this clue! When Krakatau, the enormous Indonesian volcano, erupted in 1883, the noise created was heard everywhere in the world, and the ash plume rose 50 miles into the atmosphere, darkening a vast area for days and lowering the temperature of the planet for five years.