In Southeast Asia, thousands of fires were spread across Myanmar and Thailand on March 22, 2004. In this image from the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Aqua satellite, fires have been marked in yellow. The smoke from the fires can be seen clearly against a backdrop of low clouds over the eastern half of the scene. The widespread nature of the fires suggests that they are being set intentionally for agricultural purposes. Though not necessarily immediately hazardous, such large-scale burning can have a strong impact on weather, climate, human health, and natural resources.