Giardino C, Pepe M, Brivio P A, Ghezzi P, Zilioli E
National Research Council-Remote Sensing Department, Milan, Italy.
Sci Total Environ. 2001 Mar 14;268(1-3):19-29. doi: 10.1016/s0048-9697(00)00692-6.
Some bio-physical parameters, such as chlorophyll a concentration, Secchi disk depth and water surface temperature were mapped in the sub-alpine Lake Iseo (Italy) using Landsat Thematic Mapper (TM) data acquired on the 7 March 1997. In order to adequately investigate the water-leaving radiance, TM data were atmospherically corrected using a partially image-based method, and the atmospheric transmittance was measured in synchrony with the satellite passage. An empirical approach of relating atmospherically corrected TM spectral reflectance values to in situ measurements, collected during the satellite data acquisition, was used. The models developed were used to map the chlorophyll concentration and Secchi disk depth throughout the lake. Both models gave high determination coefficients (R2 = 0.99 for chlorophyll and R2 = 0.85 for the Secchi disk) and the spatial distribution of chlorophyll concentration and Secchi disk depth was mapped with contour intervals of 1 mg/m3 and 1 m, respectively. A scene-independent procedure was used to derive the surface temperature of the lake from the TM data with a root mean square error of 0.3 degrees C.
利用1997年3月7日获取的陆地卫星专题制图仪（TM）数据，绘制了意大利亚高山伊塞奥湖的一些生物物理参数，如叶绿素a浓度、塞氏盘深度和水面温度。为了充分研究离水辐射率，使用基于部分图像的方法对TM数据进行了大气校正，并与卫星过境同步测量了大气透过率。采用了一种将大气校正后的TM光谱反射率值与卫星数据采集期间收集的现场测量值相关联的经验方法。所建立的模型用于绘制整个湖泊的叶绿素浓度和塞氏盘深度图。两个模型都给出了较高的决定系数（叶绿素的R2 = 0.99，塞氏盘的R2 = 0.85），叶绿素浓度和塞氏盘深度的空间分布分别以1 mg/m3和1 m的等高距绘制。采用一种与场景无关的程序从TM数据中导出湖泊表面温度，均方根误差为0.3摄氏度。
