Geomorphology and the Law of Unintended Consequences (Locke, 1691): Lessons from coastal weathering and erosion at Prawle (UK) and Kaikoura (NZ)

•Application to geomorphology of the Law of Unintended Consequences•The value of long term monitoring in geomorphology•Unintended consequences of field experiments may generate new and instructive landforms.

The sites of two field experiments based on micro-erosion metering, one in UK the other in New Zealand, were independently revisited respectively 33 and 17 years after installation. At both sites natural weathering and erosion processes had been inadvertently interrupted by the experimental works, leading to the development of new microscale landforms. These are interpreted in the context of modifications of the controls on weathering processes, leading to enhanced understanding of the processes themselves. This has lessons for the geomorphologist in maintaining a long-term watching brief over former experimental sites, lest some unintended and potentially beneficial outcome has ensued. This theme is embraced by the Law of Unintended Consequences.