Strategic Plan for the Journal of Geophysical Research—Earth Surface

The Editors of the Journal of Geophysical Research—Earth Surface present a new strategic plan for the journal. The journal will contribute to the objectives of AGU to embrace advancing Earth and space science for the benefit of human societies and the environment, while continuing to value fundamental science deeply. Many scientific topics covered by JGR Earth Surface are closely connected to urgent, complex problems affecting humanity and the global environment today, including climate change and a variety of natural hazards; this strategic plan is intended to ensure that published science is robust, impactful, and ultimately used to help address those problems. The plan prioritizes (1) publishing high-impact science using the highest standards of scientific ethics and rigor; (2) advancing mechanistic understanding needed to address societal challenges; and (3) ensuring that a diverse talent pool contributes to the science through a fair, equitable review and publication process

Thank You to Our 2021 Reviewers, and a New Co-Reviewing Protocol

The Editors of the Journal of Geophysical Research—Earth Surface express their appreciation to those who served as peer reviewers for the journal in 2021, and explain the newly formalized opportunity for early-career scientists to co-review manuscripts

Geomorphological and hydrological controls on sediment export in earthquake-affected catchments in the Nepal Himalaya

Large earthquakes can contribute to mountain growth by building topography but also contribute to mass removal from mountain ranges through widespread mass wasting. On annual to decadal or centennial timescales, large earthquakes also have the potential to significantly alter fluvial sediment dynamics if a significant volume of the sediment generated reaches the fluvial network. In this contribution, we focus on the Melamchi–Indrawati and Bhote Koshi rivers in central Nepal, which have both experienced widespread landsliding associated with the 2015 Gorkha (Nepal) earthquake. Using a time series of high-resolution satellite imagery, we have mapped exposed sediment along the rivers from 2012–2021 to identify zones of active channel deposition and document changes over time. Counter to expectations, we show negligible increases in coarse-sediment accumulation along both river corridors since the Gorkha earthquake. However, an extremely high-concentration flow event on 15 June 2021 caused an approximately 4-fold increase in exposed sediment along a 30 km reach of the channel with up to 12 m of channel aggradation in the Melamchi–Indrawati rivers; this event was localised and did not impact the neighbouring Bhote Koshi catchment. Based on published reports, new helicopter-based photography, and satellite data, we demonstrate that this event was sourced from a localised rainfall event between 4500 and 4800 m and that a significant fraction of the sediment was supplied from sources that were unrelated to the landslides generated by the Gorkha earthquake.</p