Last year, record-breaking fires in Brazil's Amazon rainforest sparked international outrage. But the fallout from this year's fire season, which lasts until October, could be even worse. This time around, the Pantanal region, in the west of the country, is being engulfed by flames – the majority of them caused by humans. The vast region is rapidly turning into a desert of dust and smoke, with its rich biodiversity more threatened than ever before. Our correspondents report.