Equipment Suppliers

The Sensors used for this weather station have been provided by several suppliers.

Ohmex Limited supplied the Tidalite tide gauge, located at Dock Head, Eastern Docks Southampton.

The Wind speed and direction is measured using a solid state 3 axis anemometer donated by Gill Instruments form their WindMaster range.

The temperature pressure and humidity are measured by means of a Vaisala transmitter.

Data from all the instruments is received at the VTS building by direct serial data links. The logging software is PC based and also provided by Ohmex, to a specification designed by the Hydrographic section of ABP Southampton.

Emworx Limited on Hayling Island, have given advice on system design, built the web site and supplied hosting facilities.

Chimet Support Group is responsible for the design and development of the overall system, its project management, and the development of the software used for data control and presentation.

Sensors and Data Reporting

The web site is updated every minute from the data collection site at Dock Head. Every 5 minutes the sensors data is transferred from the Hydrographer of ABP Southampton to the CSG control computer at the RNLI Station, Hayling Island. The latest sensor data is then processed to create all the reports, graphics and archives. These outputs are then transferred to the website.

The link to tidal predictions (in the Latest Report page) is from the United Kingdom Hydrographic Office.

Position coordinates (latitude and longitude) are referred to WGS84 chart datum.

Tidal heights are reduced to Chart Datum, which is approximately the level of Least Astronomical Tide.

The following table shows briefly how the reported data is derived.

Measurement Sensor Sampling Frequency Averaging Reporting Interval
Wind Speed Solid State Anemometer > Every second 2 minutes Every 5 minutes
Wind Gust Solid State Anemometer > Every second Taking max of 3-second running average Every 5 minutes
Wind Direction Solid State Anemometer > Every second Vector addition over
2 minutes
Every 5 minutes
Air Temperature Thermistor Every second 1 minutes Every 5 minutes
Barometric Pressure
(NB - Reduced to Sea Level)
Barometric Pressure Transducer Every second 1 minutes Every 5 minutes
Tidal Height Pressure Transducer Every 10 seconds 1 minutes Every 5 minutes