Launching satellites to measure carbon dioxide emissions is only part of a more integrated solution to achieving the goals of the Paris climate agreement (Nature 533, 446–447; 2016). In our view, the biggest hurdle is to reduce the high uncertainty in CO2 emission estimates — particularly from land use.
Land-use emissions are harder to quantify accurately than are those from, say, fossil fuels. To reduce uncertainties in tracking carbon from land use, it is crucial to monitor other data sources such as biomass. This can be done by remote sensing, for example with NASA's GEDI LIDAR sensor or the European Space Agency's proposed BIOMASS (P-band radar) sensor.
We also need many more ground-based measurements of biomass and CO2 exchange with the atmosphere. However, space agencies' budgets for calibrating and validating satellite products are limited, and there is inadequate coordination and data sharing between the remote-sensing and ground-based measurement communities (see A. K. Skidmore et al. Nature 523, 403–405; 2015).
We suggest that crowdsourced data from mobile-phone apps and more extensive sharing of ground-based measurements could have the greatest potential for improving the monitoring of biomass and CO2 exchange — at a fraction of the cost of satellites.
About this article
Carbon Balance and Management (2016)