Optical Spectral Reflectance Data from Chilean Coastal waters 2020

This is a collection of raw spectral downwelling and upwelling spectral measurements made in Chilean coastal waters in Regions X to XII between March and September 2020. The data may be used to calculate surface spectral reflectance leaving the water at the measured locations. \nThe data was collected as part of supporting research into the impacts of algal blooms on the Chilean aquaculture industry and their detection via satellite remote sensing. The data will be used to investigate local algorithms for retrieved satellite estimates of blooms and other bio-optical parameters in the water column.\nLineage: The dataset represents spectral measurements of downwelling and upwelling light (320-950 nm) as part of measurements to spatially characterize the bio-optical conditions spatially in Chilean Coastal waters Regions X to XII. The data were obtained as part of four (4) bio-optical campaigns undertaken with the support of the Fisheries Development Institute (IFOP, Chile). Data were collected from the different regions at the following approximate periods and number of stations: \n•\tLos Lagos - March-2020 (9 stations) \n•\tAysén - April 2020 (14 stations)\n•\tAysén – May 2020 (18 stations)\n•\tMagallanes – September 2020 (4 stations)\n\nRadiometric measurements were made at each station using a suite of RAMSES spectroradiometers, deployed as follows: (Photo 1): \n•\tRadiance under water (Lu): the RAMSES-ARC-VIS-Ti Radiance sensor (S/N: 8656) \n•\tIrradiance under water (Ed): a RAMSES-ACC-VIS-Ti Irradiance sensor (S/N: 8654) \n•\tSurface irradiance (Sky): a RAMSES-ACC-VIS-Ti Irradiance sensor (S/N: 8655) \n\nDeployment and data collection follows the standards for such measurements provided in Fargion et al. (2000). The two underwater spectroradiometers were deployed in a sampling cage for deployment into the water column (Photo 2, Photo 3). The Sky sensor was attached to a mast on the sampling vessel. Further details on the instrumentation itself can be found at: https://www.trios.de/en/ramses.html. \nThe data consist of the raw, repeated sets of spectral data obtained at each station from which spectral reflectance can be derived. The data are available as comma separated files (.csv) organised for each region and separate Ramses sensor. Supplementary data contained includes the latitude and longitude coordinates of each measurement station. \n\nThis data is designed to complement an accompanying dataset (Clementson et al. 2020; available at https://doi.org/10.25919/qbbv-v359) consisting of pigment concentration and composition, particulate and dissolved absorption coefficients and total suspended matter concentration, representing the results of analyses of water samples taken at the same time that the optical measurements have been made. The data from Los Lagos (Region X) is further complemented by two campaigns carried out by CSIRO, as part of the Integrated Aquaculture Management System (SIMA Austral) project, in October of 2017 (SIMA 2017) and March-April 2018 (SIMA 2018). \nReference:\nFargion, G.S., 2000. Ocean optics protocols for satellite ocean color sensor validation, revision 2 (Vol. 209966). National Aeronautics and Space Administration, Goddard Space Flight Center. (https://ntrs.nasa.gov/citations/20000097063). \n

本数据集收录了2020年3月至9月间，在智利沿海水域X至XII区域采集的原始下行光谱与上行光谱辐射测量数据。该数据可用于计算实测站位处水体出射的表面光谱反射率。

本数据作为辅助研究的一部分采集，旨在探究藻华对智利水产养殖业的影响，以及通过卫星遥感技术检测藻华的方法。后续将用于研发适配本地场景的算法，以通过卫星反演估算水体中的藻华及其他生物光学参数。

数据集溯源：本数据集涵盖波长范围320~950 nm的下行与上行光光谱测量数据，用于空间表征智利X至XII沿海水域的生物光学特征。数据由智利渔业发展研究所（IFOP, Chile）支持开展的4次生物光学科考项目采集。各区域的野外作业按以下大致时段与站位数量完成：
• 洛斯拉格斯（Los Lagos，X区）——2020年3月，共9个站位
• 艾森（Aysén）——2020年4月，共14个站位
• 艾森——2020年5月，共18个站位
• 麦哲伦（Magallanes）——2020年9月，共4个站位

每个站位均采用一套RAMSES系列光谱辐射计开展辐射测量，部署方式如下（照片1）：
• 水下辐射亮度（Lu）：采用RAMSES-ARC-VIS-Ti型辐射亮度传感器（序列号：8656）
• 水下辐照度（Ed）：采用RAMSES-ACC-VIS-Ti型辐照度传感器（序列号：8654）
• 海面辐照度（天空光）：采用RAMSES-ACC-VIS-Ti型辐照度传感器（序列号：8655）

本次测量的部署与数据采集流程遵循Fargion等（2000）提出的相关测量标准。两台水下光谱辐射计安装于采样笼中，可下放至水体柱层中（照片2、照片3）。天空光传感器固定于采样船的桅杆上。仪器本身的更多细节可参见：https://www.trios.de/en/ramses.html。

本数据集包含各站位采集的原始重复光谱数据，可据此推导光谱反射率。数据以逗号分隔值（.csv）文件形式存储，按区域与RAMSES传感器类型分别归档。附带的补充数据包含每个测量站位的经纬度坐标。

本数据集旨在配套另一项同期数据集（Clementson等，2020；获取地址：https://doi.org/10.25919/qbbv-v359），该配套数据集包含色素浓度与组成、颗粒与溶解性吸收系数，以及总悬浮颗粒物浓度，对应同期采集的水样分析结果。其中洛斯拉格斯（X区）的数据还补充了澳大利亚联邦科学与工业研究组织（CSIRO）在2017年10月（SIMA 2017）与2018年3-4月（SIMA 2018）开展的两次科考数据，该工作隶属于综合水产养殖管理系统（SIMA Austral）项目。

参考文献：
Fargion, G.S., 2000. 卫星海洋色传感器验证用海洋光学规程（修订版2）（第209966号）. 美国国家航空航天局戈达德航天中心. (https://ntrs.nasa.gov/citations/20000097063).