Oceanbrowser uses three different services to enable end users to select, display and evaluate time series and profiles of data of a certain kind of parameter. Oceanbrowser uses the OGC Web Services WFS and WPS for this purpose. These three services are:
- WFS - Get parameters request
- WFS - Get locations and features
- WPS - Gget time series and plot in graph
OGC web services WFS consists of various requests, for WFS these are:
http://EMODnet02.cineca.it/geoserver/wfs?service=WFS&request=GetCapabilitieshttp://EMODnet02.cineca.it/geoserver/wfs?service=WFS&request=GetCapabilities yields a capabilities document from the web feature service, or in other words all functionality provided by the services.
DescribeFeatureType describes all features described. In this case 2 services are available. The result of http://EMODnet02.cineca.it/geoserver/wfs?service=WFS&request=DescribeFeatureType http://EMODnet02.cineca.it/geoserver/wfs?service=WFS&request=DescribeFeatureType is displayed in the figure below.
This information can be used to get a certain feature via the GetFeature statement. This GetFeature statement can be completed with a query to filter on geometry and all other available entities (columns in a database) of the type names available.
For instance http://EMODnet02.cineca.it/geoserver/EMODnet/ows?service=WFS&version=1.0.0&request=GetFeature&typeName=EMODnet:p35_used&filter=<PropertyIsEqualTo><PropertyName>EMODnet:p35_id</PropertyName><Literal>EPC00005</Literal></PropertyIsEqualTo>http://EMODnet02.cineca.it/geoserver/EMODnet/ows?service=WFS&version=1.0.0&request=GetFeature&typeName=EMODnet:p35_used&filter=<PropertyIsEqualTo><PropertyName>EMODnet:p35_id</PropertyName><Literal>EPC00005</Literal></PropertyIsEqualTo> gives the contents of P35_ID EPC00005
Above is used for the first 2 services used by OceanBrowser
- Getting parameters
The first WFS is a very basic process that returns a table in xml with the list of available parameters. This table is used by OceanBrowser and displayed as follows:
OceanBrowser: distribution density of monitoring stations.
- Get locations
The Add layer button lets Oceanbrowser constructs a GetMap request on WMS layer which returns the data distribution.
Data distribution of phosphate viewed in OceanBrowser
The base URL of the WMS server for the data distribution is
For example a full request would be:
A GetMap request showing the distribution of phosphate within the bounding box10,30,45,70 (East,South,West,North).
The legend for the data distribution is a separate request. The colour represents the number of data points at the corresponding location.
- Plot time series of certain location
This is done by the OGC WPS that Deltares created to be able to extract data directly from the database. WPS stands for Web Processing Service and acts as middle ware between client side software and server side software. In this case, WPS acts between OceanBrowser and a database with all observations. The above described WFS processes are used to extract information end-users are interested in. By selecting a location, data and metadata extracted from the database can be visualised in the form of a graph. WPS also makes use of:
- getCapabilities (what can you do for me, what processes are available)
- DescribeProcess (how does a process work)
- Execute (execute a process)
Gives the list of processes availablehttp://EMODnet02.cineca.it/wps?service=wps&version=1.0.0&request=getCapabilities.
This describes the available processes of the WPS, including the inputs required, their allowable formats, and the outputs that can be produced.
The execute process is built-up on the user choice which can be found on the right hand side of the OceanBrowser portal. OceanBrowser constructs the entire HTML including the ExecuteProcess statement which triggers the WPS.
The ExecuteProcess takes a number of input arguments specified by the user. The request looks like the following:
and it returns the graph and a list of pairs [EDMO code, Local_CDI] and links to the data shopping of the used observation is provided.
Eventually, end-users would like to gain insight in observation distribution for a certain location. OceanBrowser executes the process like the above example and retrieves a timeseries like the above picture.
For the same observation, different flavours can be given (from OceanBrowser). The following is a profile request, triggered from the OceanBrowser:
and it returns a profile as in the image above.
In the example above, the EDMO codes and LOCAL_CDI’s generated and shown in OceanBrowser for the profile above looks like the following: