Manly Hydraulics Laboratory - Crowdy Head Offshore Wave Data Buoy (WAVECRH)

This is a metadata record for the Crowdy Head offshore wave data buoy (station code WAVECRH) operated by Manly Hydraulics Laboratory (MHL), NSW Office of Environment and Heritage (OEH). The buoy is moored off Crowdy Head at a water depth of approximately 80m.

This metadata record includes a down-loadable .pdf summary document which includes a map with numbered deployment locations and a listing of deployment number, location, water depth and deployment period.

Data from October 1985 to August 2011 was gathered by the Waverider system developed by the Dutch company, Datawell. The Waverider system uses an accelerometer mounted in a loose tethered buoy (0.7 or 0.9m in diameter) to measure the vertical accelerations of the buoy as it moves with the water surface. The accelerations are integrated twice within the buoy and the displacement signal so obtained is then transmitted to a shore station where it is processed to provide wave data statistics.

In August 2011, the station was upgraded with a Datawell Directional Waverider buoy. The Directional Waverider buoy utilises a heave-pitch-roll sensor, two fixed X and Y accelerometers and a three axis fluxgate compass to measure both vertical and horizontal motion. An on-board processor converts the buoy motion to three orthogonal (vertical, north-south, east-west) translation signals that are transmitted to the shore station. The directional spectrum is also routinely transmitted to the receiving station for further processing. This buoy also collects sea surface temperature (SST) data from thermistors that are mounted inside the hull of the buoys, at the base of the buoy about 0.5m below the water surface. The wave and SST data are stored on the receiving station PC before routine transfer to Manly Hydraulics Laboratory via email.

本元数据记录对应由Manly Hydraulics Laboratory（MHL）及新南威尔士州环境与遗产办公室（NSW Office of Environment and Heritage，OEH）运营的Crowdy Head离岸波浪数据浮标（站代码WAVECRH）。该浮标系泊于Crowdy Head近海，水深约80米。

本元数据记录包含一份可下载的PDF摘要文档，其中涵盖带编号部署位置的地图，以及部署编号、位置、水深和部署周期的列表。

1985年10月至2011年8月的数据由荷兰Datawell公司开发的Waverider系统采集。该系统采用安装在松散系泊浮标（直径0.7或0.9米）上的加速度计，测量浮标随水面运动时的垂直加速度。加速度在浮标内部经过两次积分，得到的位移信号随后传输至岸站，经处理后生成波浪数据统计结果。

2011年8月，该站点升级为Datawell Directional Waverider浮标。Directional Waverider浮标采用升沉-俯仰-横滚传感器、两个固定的X和Y轴加速度计以及三轴磁通门罗盘，测量垂直和水平运动。机载处理器将浮标运动转换为三个正交（垂直、南北、东西）平移信号，并传输至岸站。方向谱也会定期传输至接收站以供进一步处理。该浮标还通过安装在浮标船体内部、浮标底部水面下约0.5米处的热敏电阻采集海表温度（SST）数据。波浪和SST数据先存储在接收站的电脑上，再通过电子邮件常规传输至Manly Hydraulics Laboratory。