For millennia, fire has been used in Southeast Asia as a tool in farming and land clearing. By the 20th century, population growth, migration, and economic development had resulted in rampant conversion of native forests and peatlands for agricultural purposes. Biodiversity-and carbon-rich pristine forest and peat swamp ecosystems were cleared, drained and burned, and replaced by agroindustrial systems. Periodic occurrences of the El Niño-Southern Oscillation weather pattern produced severe droughts in Southeast Asia, during which traditional land use fires often burned out of control. While these challenges are present across the region, Indonesia-by no small margin-has seen the worst.