Continuous optical chlorophyll-a and turbidity data along R/V SONNE cruise SO295@en

Underway optical chlorophyll-a and turbidity data were collected along the cruise track with Sea-Bird Scientific ECO FLNTU sensors installed within two autonomous measurement systems, called self-cleaning monitoring boxes (SMBs). The SMBs measure alternatingly. While one box is measuring, the other one is being cleaned. The boxes switched generally every 12 hours. The water inlet for the SMBs is at about 4 m below sea surface. Observed chlorophyll-a and turbidity data were both quality controlled and a comparison for chlorophyll-a with satellite data using the GlobColour CHL1 for open ocean is additionally provided. Note that the instruments are factory-calibrated, however no post-calibration was performed due to missing reference data. The chlorophyll-a time series shows effects of non-photochemical quenching which was neither corrected nor flagged. The user may only want to use data unaffected by non-photochemical quenching (NPQ is roughly estimated to occur between 01:00 and 19:00 local time). Details on all quality control steps and the comparison with satellite data can be found in the data processing report. The resulting data set contains the original data and corresponding quality flags achieved by the quality control algorithm. The data source is given through the name of the active SMB. The data set contains data during transit time and station work. We recommend to use ship's speed to filter for only transit data.本数据集沿巡航航线采集走航式光学叶绿素-a与浊度数据，采集所用传感器为Sea-Bird Scientific ECO FLNTU，该传感器安装于两套自主监测系统——自清洁监测箱（self-cleaning monitoring boxes, SMBs）内。两套SMBs交替开展监测作业：当一套箱体处于采样状态时，另一套正进行清洁流程，通常每12小时切换一次工作状态。SMBs的取水口布设于海面下约4米处。所有实测叶绿素-a与浊度数据均经过质量控制，此外还提供了针对公海场景下GlobColour CHL1卫星数据与实测叶绿素-a数据的对比结果。需注意，本数据集所用仪器已完成工厂校准，但因缺乏参考数据，未开展后续校准工作。实测叶绿素-a时间序列存在非光化学淬灭（non-photochemical quenching, NPQ）效应，该效应未被校正或标记；经粗略估算，NPQ大致发生于当地时间01:00至19:00之间，因此用户可仅选用不受该效应影响的数据。所有质量控制流程细节及卫星数据对比方法均可在数据处理报告中查阅。本数据集包含原始观测数据及质量控制算法生成的对应质量标记，数据来源通过处于工作状态的SMB的标识予以标注。数据集涵盖航行时段及站位作业期间采集的数据，我们建议通过船舶航速进行筛选，仅保留航行过程中的采样数据。