The most recent Visible Infrared Imager Radiometer Suite (VIIRS) is not equipped with a spectral band to detect solar-stimulated phytoplankton fluorescence. The lack of such a band may affect the ability of VIIRS to detect and quantify harmful algal blooms (HABs) in coastal waters rich in colored dissolved organic matter (CDOM) because of the overlap of CDOM and chlorophyll absorption within the blue-green spectrum. A recent HAB dominated by the toxin-producing dinoflagellate Karenia brevis in the northeastern Gulf of Mexico, offshore of Florida's Big Bend region, allowed for comparison of the capacities of VIIRS and Moderate Resolution Imaging Spectroradiometer (MODIS) to detect blooms in CDOM-rich waters. Both VIIRS and MODIS showed general consistency in mapping the CDOM-rich dark water, which measured a maximum area of 8900 km2 by mid-July 2014. However, within the dark water, only MODIS allowed detection of bloom patches—as indicated by high normalized fluorescence line height (nFLH). Field surveys between late July and mid-September confirmed Karenia brevis at bloom abundances up to 20 million cells·L−1 within these patches. The bloom patches were well captured by the MODIS nFLH images, but not by the default chlorophyll a concentration (Chla) images from either MODIS or VIIRS. Spectral analysis showed that VIIRS could not discriminate these high-phytoplankton water patches within the dark water due to its lack of fluorescence band. Such a deficiency may be overcome with new algorithms or future satellite missions such as the U.S. NASA's Pre-Aerosol-Clouds-Ecology mission and the European Space Agency's Sentinel-3 mission.
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机译：最新的可见光红外成像辐射计套件（VIIRS）并未配备用于检测太阳刺激的浮游植物荧光的光谱带。由于蓝绿色光谱中CDOM和叶绿素吸收的重叠，缺少这样一个谱带可能会影响VIIRS在有色溶解有机物（CDOM）丰富的沿海水域检测和定量有害藻华（HAB）的能力。最近在墨西哥东北部，佛罗里达大弯曲地区离岸的产毒素的鞭毛小孢子藻（Karenia brevis）占主导地位的HAB，可以比较VIIRS和中等分辨率成像光谱仪（MODIS）检测富含CDOM的水中水华的能力。 。 VIIRS和MODIS都显示了对富含CDOM的暗水进行测绘的总体一致性，该暗水到2014年7月中旬的最大面积为8900 km 2 。但是，在暗水中，只有MODIS允许检测到斑点补丁-如高归一化荧光线高度（nFLH）所示。 7月下旬至9月中旬的田间调查证实，这些斑块内的短花气单胞菌的花开度高达2000万个细胞L -1 。 MODIS nFLH图像很好地捕获了大花斑块，但MODIS或VIIRS的默认叶绿素a浓度（Chla）图像却不能很好地捕获它们。光谱分析表明，由于缺乏荧光带，VIIRS不能区分暗水中的这些高浮游植物水斑。可以通过新算法或未来的卫星任务（例如美国NASA的气溶胶-云-生态学前任务）和欧洲航天局的Sentinel-3任务来克服这种缺陷。
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