Near-bottom hydrosedimentary data from current profiler moorings, Aulne River estuary, France

timeseries of water level and near-bottom (1.3 m above bottom) velocity from current profilers, and near-bottom salinity and suspended sediment concentration from ysis deployed with the current meters. two deployments in 2013: february and september. two locations in the estuary: site 1 (48° 16.842’ n, 004° 16.009’ w), and site 3 (48° 14.851’ n, 004° 10.140’ w). water level was corrected for variations in atmospheric pressure.moored instruments were deployed for 3 weeks at two locations in the aulne estuary in february and september 2013. each mooring consisted of an acoustic doppler current profiler and a ysi 6290 v2 equipped with turbidity, conductivity, salinity, and pressure sensors. a nortek awac wave and current profiler (frequency 1 mhz) was deployed along with a ysi 6290 v2 at site 1, near the mouth of the aulne. an rd instruments workhorse acoustic doppler current profiler (adcp, 1.2 mhz) was deployed along with a ysi 6290 v2 at site 3. the awac and adcp were programmed to measure a 2-minute burst average at 1hz every 5 minutes for profiles of currents and acoustic backscatter. the internal compasses of the current profilers were calibrated and the pressure sensors for all instruments were reset before each deployment. the turbidity sensors of the ysis were calibrated before deployment with a 3-point calibration using distilled water and hach formazin turbidity standard at 4000 ntu, diluted to 400 and 1000 ntu. the ysi turbidity sensors were calibrated again to ssc with water samples. the ysis were programmed to take 1 measurement every 5 minutes, and were moored approximately 10m away from the current profilers at a height of 1.3 m above bottom. note that all salinity data are expressed according to the practical salinity scale.water level data from the awac and the adcp were corrected for post-deployment changes in barometric pressure using the inverse barometer method, and in the case of the awac, for a systematic pressure offset. the along-channel velocity direction was determined for each current profiler from histograms of near-surface velocity direction. during february the site 1 ysi failed partway through the deployment, so the awac backscatter was converted to ssc to compensate for the lost data. the ssc timeseries from the moored ysi was used to calibrate the awac echo intensity to ssc. the echo intensity output by the awac was converted to relative backscatter intensity with the sonar equation. the backscatter intensity (bi) in the current profiler bin closest to the height of the moored ysi above bottom was regressed against the timeseries of calibrated ssc from the moored ysi. the final form of the regression equation between bi and ssc was: 10log(ssc)=a*bi + b, where a and b are correlation coefficients and ssc is the suspended sediment concentration in mg l-1. two regression equations were used in converting bi to ssc, to improve regression accuracy for bi greater than -45 db. separate calibrations for flood and ebb did not result in an improved regression coefficient. it should be noted that some maximum values during the second spring tide at site 1 in february may have been underestimated. before the ysi failed, the calibrated awac ssc sometimes underpredicted the ysi ssc because of a high amount of scatter in the regression relationship. it is therefore likely that peak ssc values were underestimated during the second spring tide.

该数据集记录了来自流速剖面仪的水位和底部附近（距底部1.3米处）的流速数据，以及与流速仪配合使用的底部附近盐度和悬浮颗粒浓度数据。数据采集于2013年2月和9月进行的两次部署。研究区域位于河口两个地点：站点1（北纬48°16.842'，西经004°16.009'）和站点3（北纬48°14.851'，西经004°10.140'）。水位数据经过大气压力变化校正。在2013年2月和9月，于奥恩河三角洲的两个地点部署了锚定仪器，持续观测3周。每个锚定装置包括一个声学多普勒流速剖面仪和一个配备有浊度、电导率、盐度和压力传感器的YSI 6290 v2。在站点1，奥恩河口附近，还部署了一台Nortek AWAC波浪和流速剖面仪（频率1 MHz），以及一台YSI 6290 v2。在站点3，部署了一台RD仪器Workhorse声学多普勒流速剖面仪（ADCP，频率1.2 MHz）和一台YSI 6290 v2。AWAC和ADCP被编程为每5分钟测量一次，频率为1Hz的2分钟爆发平均电流剖面和声学回波。流速剖面仪的内部罗盘进行了校准，所有仪器的压力传感器在每次部署前都进行了重置。YSI的浊度传感器在部署前使用去离子水和Hach formazin浊度标准（4000 ntu，稀释至400和1000 ntu）进行了三点校准。YSI浊度传感器再次使用水样校准至悬浮颗粒浓度（SSC）。YSI被编程为每5分钟进行一次测量，并锚定在距流速剖面仪大约10米远，底部以上1.3米的高度。需要注意的是，所有盐度数据均按实用盐度尺度表示。AWAC和ADCP的水位数据使用逆气压计法校正了部署后的气压变化，AWAC在压力系统偏差方面也进行了校正。根据近表面流速方向的直方图确定了每个流速剖面仪的沿渠道流速方向。在2月，站点1的YSI在部署中途失效，因此将AWAC回波转换为SSC以补偿丢失的数据。锚定YSI的SSC时间序列用于校准AWAC回波强度至SSC。AWAC输出的回波强度通过声呐方程转换为相对回波强度。在锚定YSI底部以上高度最近的流速剖面仪的回波强度（BI）与锚定YSI校准后的SSC时间序列进行了回归分析。BI和SSC之间的最终回归方程形式为：10log(SSC) = a * BI + b，其中a和b为相关系数，SSC为悬浮颗粒浓度（mg/L）。在将BI转换为SSC时使用了两个回归方程，以改善大于-45 dB的BI的回归精度。对于涨潮和落潮的分别校准并未提高回归系数。需要注意的是，在2月第二个春潮期间，站点1的一些最大值可能被低估。在YSI失效之前，校准后的AWAC SSC有时会低估YSI SSC，因为回归关系中有大量的散射。因此，很可能在第二个春潮期间峰值SSC值被低估。