Sydney, New South WalesIn the wake of the enormous fires that have razed huge swathes of drought-stricken Australia, scientists fear that when rains eventually fall, they will wash charred debris into rivers, dams, and the ocean, killing wildlife and even tainting the drinking supplies of major cities, such as Sydney.

For many weeks, ash, soot, and blackened gum tree leaves have collected along the shorelines of Sydney’s beaches, clogging the waves and lapping in the tide. Originating in fires blazing in forested areas to the west, the debris has been carried on the breeze along with the pungent bushfire smoke that blanketed Australia’s largest city for much of December.

But what has carried on the wind is just a taste of the huge quantities