Earth observation as a tool for tracking progress towards the Aichi Biodiversity Targets

Biodiversity is continuing to decline. This crisis has been recognised by the Convention on Biological Diversity (CBD), whose members have set ambitious targets to avert ongoing declines in the state of biodiversity by 2020. These so called "Aichi Biodiversity Targets" (ABTs) are organized around five strategic goals, with indicators showing the level of progress made towards each target. Currently, measurements of many ABT indicators are not available. The Essential Biodiversity Variable (EBV) framework, developed by the Group on Earth Observations Biodiversity Observation Network (GEO BON), attempts to form a coherent and harmonised set of observations of biodiversity. In this paper, we explore the potential role of Earth Observation (EO) as a tool to support biodiversity monitoring against the ABT and EBV frameworks. We show that EO-based measurements are adequate for assessing progress towards 11 out of 20 ABTs. In addition, 14 of the 22 candidate EBVs have a fully or partly remotely-sensed component and can be considered as Remote Sensing Essential Biodiversity Variables (RS-EBVs). Those with a partial EO component require further in-situ data and/or modelling effort to complete the EBV. While the status of biodiversity can be assessed with both fully and partly measured RS-EBVs, assessing trends is more challenging, particularly for partly measured RS-EBVs, as coincident time series of EO and supporting data are lacking. A synthetic pathway for developing generic biodiversity indicators using RS-EBVs is proposed.