With appearance of new low-cost sensor technologies, monitoring air pollution is in the hands of everyone. Novel sensor technologies open the opportunity to monitor air quality at spatial resolutions not possible to reach with traditional monitoring systems. Low-cost sensors are small, portable and easy to use. Citizens can now contribute to monitor the environment. The CITI-SENSE COT contains a number of elements that together provides the foundations of a complete Citizens' Observatory.
These elements will be presented here from a user perspective, with an emphasis on the elements that have been realised for the nine city locations in the CITI-SENSE project. This includes support for collection of data and observations through sensors, mobile apps and surveys and also elements for analysis and visualisation of observations through widgets and web portals.
In the CITI-SENSE project the focus is on Air Quality with the following elements: Sensors – a set of sensor platforms has been developed for both static and mobile air quality sensors, including monitoring of CO/CO2, NO, SO, PM, Radon, Temperature, Humidity etc. They are providing their observations into a common data server. Mobile Apps – a set of mobile apps has been developed to support user perceptions and user answers to surveys and questionnaires, with a focus on air quality questions. A tool for the creation of Surveys and Questionnaires is being used for the creation of both web-based and smartphone based surveys. Reusable Widgets have been developed to visualise the collected observations in different ways, typically based on time-based and location-based queries. A Web Portal is being provided including references for individual web portals for each of the nine city locations. Methods includes guidelines for how to use sensors, mobile apps and portals in order to support citizens involvement and empowerment in environmental monitoring of air quality.
The CITI-SENSE COT contains a number of elements that together provides the foundations of a complete Citizens' Observatory. These elements will here be presented from a developer perspective, with an emphasis on the technical elements and frameworks that can be reused for the creation of new Citizens' Observatories.
The elements provided through the developer's perspective of the CITI-SENSE COT include Guidelines for how to set up and test sensors packages and sensor platforms, open source software for the creation of mobile apps possibly with attached mobile sensors, software for the creation of surveys/questionnaires and a data model and data storage service for the storage of sensor and human observations. The Architecture follows a scalable architecture with an option for multiple front end sensor systems as well as multiple mobile apps for data. A generic framework for multiplatform mobile observation apps is provided. The CITI-SENSE Data Model version 2.2 is implemented in a WFS server, and supports the storage of air quality observations as well as questionnaires. The Big Data aspects of sensor data streaming and handling of velocity of sensor data is handled by an option of delegating the first storage step to sensor platform dedicated storage services, with a subsequent storage into the common WFS server supporting the CITI-SENSE Data Model. This server supports access to the data through multiple representation formats such as XML, CSV and JSON. In addition there is an experimental export to linked data through a SPARQL end-point. Reusable Widgets has been developed to visualise the collected observations in different ways, typically based on time-based and location-based queries and these can be used both through development in smartphone apps as well as in portal development.