Since the monitoring of environmental emissions is mostly in the hands of regulatory authorities, collected data may not be easily observed by the interested public. Centrally stored data may also tempt the authorities or others to manipulate the historical record for political or liability reasons. To enable timely, transparent and integrity-protected collection and presentation of emission data, we propose and implement Tremble, an emission monitoring system based on blockchain and IoT sensors. Tremble employs a hybrid storage approach to lower the cost of storage compared to using a pure blockchain without losing data integrity. It provides web interfaces and visualizations for end users to query emission values they are concerned about. Qualitative and quantitative studies involving a total of 62 subjects demonstrate the usability of the system.    «

Since the monitoring of environmental emissions is mostly in the hands of regulatory authorities, collected data may not be easily observed by the interested public. Centrally stored data may also tempt the authorities or others to manipulate the historical record for political or liability reasons. To enable timely, transparent and integrity-protected collection and presentation of emission data, we propose and implement Tremble, an emission monitoring system based on blockchain and IoT sensors...    »