File:Flooding on the MacIntrye River, Australia (MODIS 2021-12-13).jpg

English: An unusually wet spring has filled the rivers of New South Wales and southern Queensland to overflowing, causing serious damage to property and the loss of at least one life. According to the Canberra Times, on November 23, 2021, the State Emergency Services responded to 118 calls for help due to flooding, fallen trees, and leaking roofs with more rain on the way. Australia’s ABC News reported on December 1 that two cars were swept off a road as major flooding continued to inundate homes and spark evacuations in southern Queensland, leading to the rescue of one driver and the death of the other.

Although the flooding started in November, it has continued into mid-December. On December 13, the Bureau of Meteorology (BOM) published a Flood Warning for the Border Rivers (the rivers that flow near the border of Queensland and New South Wales). They advise a Major Flood Warning for the Weir River and Moderate Flood Warning for the Macintyre River continued, although the waters were beginning to ease.

On December 10, the Moderate Resolution Imaging Spectroradiometer (MODIS) on board NASA’s Aqua satellite acquired a false-color image centered on flooding of the Macintyre River. This type of false-color image (bands 7,2,1) uses a combination of visible and infrared light to better distinguish between water and land. Water varies in color from electric blue to navy. Vegetation is bright green and bare ground is earth-toned. Clouds are pale blue-green. A black line, representing the border between Queensland (north) and New South Wales (south) has been overlain on the image. At ordinary levels, the Macintyre River forms the boundary between those two Australian states, but the flooding has expanded the river well north and south of the normal course.

While this single image shows significant flooding, it’s informative to compare two different MODIS images of the same area to appreciate the change over time. The NASA Worldview App allows such a comparison with a single click. To view the region on May 13, 2021, and compare with this image acquired on December 10, click here. On May 13, the Macintyre was barely discernable. By December 10, the river had broken its banks and spread onto the surrounding flood plains, as had nearby rivers in New South Wales.