Moderate resolution imaging spectroradiometer (MODIS) continues to be an important instrument for NASA’s earth observing system. Terra and Aqua MODIS have produced more than 22 and 20 years of global datasets that have significantly helped scientists better understand the Earth’s systems, respectively. The MODIS level-1B (L1B) algorithms use the uncalibrated, geolocated Earth scene observations as input and convert the instrument response into calibrated reflectance and radiance, which are used to generate the downstream science products. The sustained calibration and characterization activities undertaken by the MODIS characterization support team have resulted in several upgrades to the L1B algorithms to maintain accurate calibration in the data products. We present an overview of the L1B algorithm designated as Collection 7. Various algorithm enhancements both in the reflective bands and thermal bands characterization are currently under science testing and evaluation. Once applied in data processing (projected in early 2023), they are expected to manifest in improved science products, both in terms of radiometric accuracy and long-term stability.

中文翻译：

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Terra 和 Aqua MODIS 合集 7 级 1B 算法

中分辨率成像光谱仪（MODIS）仍然是美国宇航局地球观测系统的重要仪器。Terra 和 Aqua MODIS 制作了超过 22 年和 20 年的全球数据集，它们分别显着帮助科学家更好地了解地球系统。MODIS level-1B (L1B) 算法使用未校准的地理定位地球场景观测数据作为输入，并将仪器响应转换为校准后的反射率和辐射率，用于生成下游科学产品。MODIS 表征支持团队进行的持续校准和表征活动导致对 L1B 算法进行了多次升级，以保持数据产品的准确校准。我们概述了指定为 Collection 7 的 L1B 算法。反射带和热带表征的各种算法增强目前正在科学测试和评估中。一旦应用于数据处理（预计于 2023 年初），它们有望在改进的科学产品中体现出来，无论是在辐射精度还是长期稳定性方面。