Whilst within the "Tides" tab, different sites can be selected, by clicking on the name of the site of interest. Depending on the users screen size, these can be found either within "Stations", or they will already be present within the bar across the top of your browser page (this is dependent upon screensize).
This page will display the data recorded by any active tide gauges within the system/cluster.
Structure of the Tides display
At the base of the page, the system overview message is present along with the count down timer, indicating the number of seconds until the window is refreshed. When the counter expires, the Port-Log database will provide the latest set of sensor records to the web display. Depending on the sampling frequency of the sensors, the latest data record may not change with every refresh of the web display.
A time-series graph displaying observed tidal height for a given site along with predictions takes up the majority of this page. The length of the time-series is 18 hours. The plot includes +6 hours of predictions, and <12 hours of recent tidal height values.
Just above the plot, and as can be seen above, a brief overview of the current state of the tide can be found. To the left, an arrow indicates whether the tide is ebbing or flooding, and to the right a real-time value of the surge/cut (in relation to predictions) can be found.
Menu Options
User can move between different sections of the system. Here, "Tides" has been selected.
The latest current observed tidal value plus the trend of the recent observations. An upwards pointing arrow indicates that the tide is 'flooding', whilst a downwards facing arround would indicate that the tide is 'ebbing'.
A snap-shot of the observed tide in relation to the predictions, with the value given being the numerical difference between predictions and observations. The arrow indicates whether the surge value is increasing or decreasing. Red text indicates the a cut in the tide (i.e. lower than predicted)
A site-specific tidal graph. The blue line indicates predictions, whilst the red line indicates the observed tidal height. These graphs display 12 hours of previous observed tidal height (with predictions also), along with 6 hours of tidal predictions. The dots present on each line indicate the tidal turning times. The shaded plot at the base displays the difference between the predictions and observations, therefore indicating whether the tide is in a surge or cut state. Below zero indicates a cut, whilst above zero indicates surge.
Pressing the up and down arrow keys will move the time-series back or forward by 1 day at a time.
Hovering the mouse over the lines will display the actual time and values of the observation or prediction.
A timer indicating the system time (time zone dependent on client specifications), with sunset time given as an indication of remaining light for the day.
A timer to indicate when the browser will refresh (usually every 10 seconds). If there is new data to display, this will replace values already in place upon the web page.
