I can’t change the world by myself. This is a common thought citizens share when it comes to climate action. Climate change campaigns usually aim at raising awareness and triggering action to reduce our footprint. However, these campaigns often fail as they are designed in a top-down manner. The ChallengeYeti app was created on a psychological-technological foundation focusing on motivational and bottom-up approaches to bridge this knowledge-action gap. Hence, the app primarily strives to trigger behavioral change in a fun and social way. This paper introduced the app and its functionalities, its theoretical and technical background, its implementation, its expected impact on behavioral change, and lastly, future challenges of the app.

Climate change and environmental degradation present significant threats globally. The various sources report on different climate records. The European Green Deal aims to counteract these challenges by achieving zero emissions by 2050, with a significant focus on citizen involvement. Citizen science initiatives play a critical role in engaging the public in climate action through data collection and monitoring of environmental impacts. Technological tools, such as dashboards, facilitate this involvement by visualizing complex climate data, raising awareness, and bridging the knowledge-action gap. This paper discusses a dashboard (developed within the Horizon 2020 project I-CHANGE) designed to engage citizens in environmental data collection and analysis. The Dashboard, co-designed with scientists and stakeholders, supports citizens in viewing, understanding, and interpreting data collected with low-cost sensors and through crowdsourcing activities. The paper gives an overview of the Dashboard's design, implementation, data integration, and its role in fostering public engagement and environmental consciousness.

Saša Vranića*, Hrvoje Matijevićb & Miodrag Roićaa Faculty of Geodesy, Chair of Spatial Information Management, Institute for Applied Geodesy, Zagreb, Croatiab IGEA L.L.C., Varaždin, Croatia* Corresponding author. Email: svranic@geofModern land administration systems must fulfil the emerging need for a faster and more efficient processing of real estate transactions. In order to achieve such a goal, one way to go can be to outsource a larger segment of the cadastral geometry updating process to the actors external to the organisation maintaining the data. In case the spatial component of the combined legal–spatial transactions is to be outsourced, the underlying transaction processing system must be able to autonomously handle all possible cases in a safe and consistent manner. In this paper we developed a framework that can be used to design a system that is based on standard database transaction concepts and guarantees the safe processing of externally prepared transactions on polygon-based cadastral parcels. In order to be able to detach the process of editing from the consistency control, we adjusted our basic concepts to only consider the net effect of a transaction. In creating the framework we first detect all possible types of transactions. We do that by observing the cardinalities of the transaction’s affected and the resulting sets of parcels and the identities of each set’s members. Following the detection, we attach the basic integrity constraints to each of the transaction types. Finally we classify the detected transaction types into two subtypes with the primary criteria being the strict or relaxed requirements regarding the planar partition correctness. A strict definition of what can be done within each such transaction type provides a reference that can be used for linking the legal and the spatial component of a combined legal–spatial transaction. In order to substantiate the developed framework, we describe the implementation of a proof of the concept system.