Physical and chemical profile data collected from CTD in the R/V Knorr cruise KN200-2 during March 2011 in the North Atlantic Ocean (NODC Accession 0100287)

The dataset consists of 100 CTD casts in the region north of Flemish Cap. Some casts cover the full water column, while others only cover the upper 1000 db. The CTD casts were obtained with a SeaBird SBE911+ system, measuring temperature (2 sensors), conductivity (2 sensors), pressure, beam transmission, oxygen (plumbed in series with the primary T/C sensor pair), chlorophyll fluorescence, and turbidity. All sensors were sampled at 24 Hz. The data were processed using the SeaBird data processing software suite, SBEDataProcessing-Win32. A low pass filter, with time constant of 0.15 s, was applied to the pressure record. To account for the transit time between the temperature and conductivity sensors, the conductivity measurements were aligned with the temperature measurements using empirically determined time delays. The primary conductivity was delayed by 0.011 s relative to pressure (this is in addition to the advance of 0.073 s which is performed by the SeaBird deckbox during data acquisition, thus resulting in a net advance of 0.062 s). The secondary conductivity was advanced by 0.050 s. The oxygen voltage was advanced by 4 s relative to pressure. A correction for conductivity cell thermal mass effects was applied to both conductivity channels using the parameters recommended by SeaBird (alpha=0.03, 1/beta=7.0). The temperatures, conductivities, and oxygen voltage were then median filtered using a 7-scan window. A loop edit step was then applied, whereby portions of the cast in which the pressure was not changing sufficiently fast (0.2 dbar/s) were removed. This was followed by computation of salinity, potential temperature, potential density, sound velocity, geopotential anomaly, and oxygen concentration. Finally, the data from the downcast were averaged into 1 dbar bins. Further details of the CTD data processing can be found in the header portion of the individual cast files. The final data files contain raw sensor values (1 dbar bin averages) plus a number of derived variables (e.g. potential temperature, salinity, sigma-theta, oxygen). A full list of the output variables is contained in the header portion of the cast files. The casts were visually examined to determine the quality of the data from the 2 separate sensor suites (primary and secondary). A header line was placed in each file indicating the preferred sensor pair (PRIMARY or SECONDARY) if one was bad or whether both were of equal quality (BOTH GOOD).本数据集包含弗拉芒海台以北海域的100组温盐深剖面测量（CTD，Conductivity-Temperature-Depth）站位数据。部分站位覆盖完整水柱，其余站位仅覆盖上层1000分巴水深范围。本次数据采用SeaBird SBE911+系统采集，该系统可测量温度（2个传感器）、电导率（2个传感器）、压力、光束透过率、氧浓度（与主温盐传感器对串联安装）、叶绿素荧光及浊度。所有传感器的采样率均为24赫兹。 数据处理采用SeaBird数据处理软件套件SBEDataProcessing-Win32完成。首先对压力记录施加时间常数为0.15秒的低通滤波。为校正温度与电导率传感器间的传输时延，采用经验确定的时间延迟将电导率测量数据与温度测量数据对齐：主电导率传感器相对压力传感器延迟0.011秒（该校正叠加于SeaBird甲板箱在数据采集阶段执行的0.073秒超前校正，最终净超前量为0.062秒）；副电导率传感器超前0.050秒。 氧传感器电压信号相对压力传感器超前4秒。采用SeaBird推荐的参数（alpha=0.03，1/beta=7.0）对两个电导率通道的电导池热质量效应进行校正。 随后采用7扫描窗口对温度、电导率及氧电压信号进行中值滤波，继而执行剖面编辑步骤，剔除压力变化速率不足0.2分巴/秒的剖面区段。之后计算盐度、位温、位密度、声速、位势异常及氧浓度。最终将下行剖面的数据按1分巴间隔进行平均。更多CTD数据处理细节可参见各剖面文件的头部信息。 最终数据文件包含原始传感器值（1分巴间隔平均结果）及多种衍生变量（如位温、盐度、sigma-theta、氧浓度），输出变量的完整列表可参见剖面文件的头部信息。研究人员对所有剖面进行目视检查，以评估两套独立传感器组件（主、副传感器组）的数据质量。每个文件的头部均添加一行标注，说明优先选用的传感器对（主传感器对或副传感器对，若其中一组存在缺陷），或两组质量均合格（BOTH GOOD）。