Concerns about data linking delta land gain to human action

This is a Nature Matters Arising submission to the Nienhuis et al., 2020 paper: Nienhuis, J. H., Ashton, A. D., Edmonds, D. A., Hoitink, A. J. F., Kettner, A. J., Rowland, J. C., & Törnqvist, T. E. (2020). Global-scale human impact on delta morphology has led to net land area gain. Nature, 577(7791), 514-518.

Abstract:

River deltas are diverse, economically and ecologically important ecosystems that are increasingly vulnerable to environmental change. A recent study reported that global-scale human impact on delta morphology has led to net land area gain (Nienhuis et al.¹). However, we argue that an unconventional definition of deltas, miscellaneous coastal features unduly characterized as deltas and misidentified delta area changes led to spurious statistics in the study by Nienhuis et al.¹ and that a recently published correction² does not address our concerns. We call for the rigorous verification and analysis of large environmental datasets.