In November 2015, the Doce River basin was struck with Brazil’s worst environmental disaster: the collapse of an iron ore mining waste water dam delivering about 60 Mm³ of contaminated mud that traveled from its headwaters to the Atlantic Ocean. We analyzed the impact of the tailings dam failure on the turbidity of the Doce River plume and coastal waters based on remote sensing methods applied to Landsat and MODIS-Aqua imagery. Turbidity maps were obtained using a semi-analytical algorithm that uses a two band (i.e., red and near infrared) selection scheme to optimize the retrieval for a wide range of turbidity levels. The dam failure occurred in the context of a severe hydrological drought, but despite the abnormally low streamflow the turbidity front of the Doce River plume at the coast peaked to levels above 1000 FNU after the disaster. With subsequent rainfall-runoff events, the deposited mud within the river-estuary system continued to be washed out and cause high turbidity levels with extensive plumes over the coastal zone. The high turbidity (>20 FNU) plume front reached 11 km off the coast towards the southern shelf, the moderate turbidity plume (10–20 FNU) reached 39 km, and the low turbidity plume (<5 FNU) exceeded 75 km. Changes on the dominant wind pattern from NE to S, inverted the river plume direction towards the northern shelf, but the high turbidity plume stayed near the mouth (<5 km). The mud deposited from the disaster in the inner shelf remained a source of fine sediment resuspension for the coastal front turbidity during 2016 and 2017, with the intensification of coastal resuspension processes during the winter season. The combination of higher spatial and temporal resolutions of Landsat and MODIS-Aqua imagery, respectively, with auxiliary in situ stream flow and turbidity measurements allowed disentangling the impacts caused by the tailings dam failure from the natural sources of suspended sediment that influence the variability of coastal water turbidity.

2015年11月，多西河流域遭受了巴西最严重的环境灾难：一座铁矿石开采废水坝的坍塌，输送了约60 Mm ^3的水。从上游源头流向大西洋的污染泥浆。我们基于应用于Landsat和MODIS-Aqua影像的遥感方法，分析了尾矿坝破坏对Doce河羽流和沿海水域浊度的影响。使用半分析算法获得浊度图，该算法使用两个波段（即红色和近红外）选择方案来优化各种浊度水平的检索。大坝的倒塌是在严重的水文干旱的背景下发生的，但是尽管水流异常偏低，但海岸的Doce河羽流的浊度前沿在灾后达到了1000 FNU以上的水平。随后发生降雨径流事件，河口系统内沉积的泥浆继续被冲走，并造成高浊度和沿海地区大量羽状流。高浊度（> 20 FNU）的羽状流向海岸以南到达南海陆架11公里，中浊度（10–20 FNU）的羽状流达到39 km，低浊度（<5 FNU）的羽状流超过75 km。从东北向南的主导风型变化，使河羽向北架子反转，但高浊度羽留在河口（<5 km）附近。随着冬季沿海悬浮过程的加剧，2016年和2017年期间，由于内陆架架灾害而沉积的泥浆仍然是沿海前混浊的细小悬浮沉积物的来源。现场的流量和浊度测量可以将尾矿坝破坏引起的影响与悬浮泥沙的自然来源区分开来，从而影响沿海水浊度的变化。