Ubiquitous monitoring of human sunlight exposure in cities

Despite recent advances in mobile wearable sensing, there isn't a cheap, non-intrusive, and accurate way of knowing how much sunlight we are exposed to. This research article introduces a novel approach that leverages on smart phone user's data and utilises a state of the art 3D Solar Radiation Model known as the (SORAM) to calculate how much sunlight a person is exposed to in urban environments. The SORAM algorithm is used to calculate both the direct and the diffused sunlight exposure based on the person location, the local weather, sun location, atmospheric effects (including pollution), and shadow from buildings. We achieve this, through the use of a specially designed smartphone application that only gathers the user location and time data. This information is then sent remotely to a server that securely and privately processes the data. The server amalgamates multiple data streams together to calculate the sunlight exposure and sends the information back to the user, visualized as a set of useful time series and daily averaged results. This will ultimately allow the user to be more informed about sunlight exposure and compare it with daily recommended levels to encourage positive lifestyle behaviour change.