ABSTRACT Observations by satellite sensors provide data on inland water systems at spatial and temporal coverage superior to current monitoring programmes. We derived an empirical relationship for Secchi depth using in situ data from eight lakes and data from the Landsat 5 Thematic Mapper, Landsat 7 Enhanced Thematic Mapper Plus and Landsat 8 Operational Land Imager between 1999 and 2018 in the Rotorua Lakes Region in New Zealand. This relationship was then applied to all Landsat data of 23 lakes in that region. A trend analysis on annual and summertime averages of Secchi depth revealed several statistically significant and positive trends, indicating improving water clarity. Our trends were in agreement with those based on in situ observations illustrating the opportunities of remote sensing time series data for lake monitoring and management.

中文翻译：

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新西兰罗托鲁瓦湖区 18 年来遥感水清澈度的区域趋势

摘要 卫星传感器的观测提供了优于当前监测计划的空间和时间覆盖范围内的内陆水系统数据。我们使用 1999 年至 2018 年新西兰罗托鲁瓦湖区的八个湖泊的原位数据和来自 Landsat 5 专题地图绘制器、Landsat 7 增强型专题地图绘制器和 Landsat 8 操作陆地成像仪的数据推导出了 Secchi 深度的经验关系。然后将该关系应用于该地区 23 个湖泊的所有 Landsat 数据。对 Secchi 深度的年度和夏季平均值的趋势分析揭示了几个具有统计意义的积极趋势，表明水的透明度有所提高。我们的趋势与基于原位观测的趋势一致，说明遥感时间序列数据用于湖泊监测和管理的机会。