Introduction
This is a description of an experimental alternative web interface for the Sentinel national bushfire monitoring system. It uses a subset of the features of the production system and a simplified interface designed for mobile devices, such as smartphones, PDAs and ultra-mobile PCs. Do not use this interface for real fire tracking, use the production version of the Sentinel system from DIGO, CSIRO Land and Water and Geoscience Australia.
About SENTINEL
Geoscience Australia obtains infrared data from NASA Earth Observation Satellites. High temperature "hot spots" are identified and mapped. The maps are available via the web to firefighters and the general public.
The Sentinel Bushfire Monitoring (aka Sentinel Hotspots) System is an internet-based mapping tool designed to provide timely spatial information to emergency service managers across Australia. The mapping system allows users to identify fire locations with a potential risk to communities and property. It can be accessed using a standard web browser. ...
Following the severe bush fires that swept though New South Wales and the Australian Capital Territory in the summer of 2001-02, the Defence Imagery and Geospatial Organisation (DIGO) identified a pressing need to implement a system to detect and monitor bush fires. The collaborative effort between DIGO, CSIRO Land and Water and Geoscience Australia resulted in a system that helps to protect Australian communities during bushfires. ...
From What is Sentinel Hotspots?, DIGO, CSIRO, Australia, 2006
The initial version of system was made available in 2003. Shortly after its release bush-fires in Canberra showed the usefulness, but also limitations of the system. A new version of the software provided a choice of a dial-up version for low speed connections or full service broadband version. However, the service was still not suitable for use by handheld devices with small screens and slow links.
Alternative SENTINEL Interface
Support for the web mapping services WFS and WMS in the new version of Sentinel offered a way to provide alternative interfaces to the system. WMS was used to ceate a demonstration low bandwidth/small screen interface for handheld devices.
Web Map Service (WMS) is a standard interface to provide a map in response to parameters sent in a URL. This URL is sent to the Sentinel system, which creates a map from the database and sends it back to the web browser as a PNG image.
Web Feature Service (WFS) provides a web services interface to get the geographic data in XML format. This can be sued by a more sophisticated application to process the fire locations. The WFS and WMS Capabilities Files provide a list of features available via the interface in the form of an XML file. An example of the use of WFS it might be to request a list of fires in a particular area and sound an alarm if one is detected. But only WMS is used for this demonstration to display a simple map.
The demonstration provides an XHTML web based interface for a subset of Sentinel features. Unlike the production Sentinel interface, the demonstration uses server side PHP to create a simple web form. The user can select the map size by chaning fileds on the form to suit their device. The default is QVGA size, suitable for a handheld device. By default only the fire locations and a simple line drawing map is shown, to reduce the size of the image file. Satellite imagery can be requested, but increases the size of the file and therefore the amount of bandwidth needed on the communcations link.
