Using the enigmatic peak of the Matterhorn, this work nicely illustrates how anthropogenic climate warming is changing the face of our mountains. Warming permafrost and changing rock-strength destabilizes rock-mass and results in rockfall that poses serious hazards for adjacent valleys.

How does grainsize vary along rivers, and what are the controls? Based on an extensive dataset compiled in a citizen-science survey across Scotland, Towers et al. find that in post-glacial landscapes commonly used global environmental factors provide little explanation. Instead, the local sediment input from glacially sculpted landforms and emplaced deposits largely determine the high spatial variability of grainsizes.

The paper by Leger et al. presents a large-scale reconstruction of glacial sediment transport in the Alps, offering both novel insights and a versatile computational framework for investigating glacial processes at Quaternary time scales. The study's relevance spans paleo-glacier dynamics, sediment transport, and landscape evolution in alpine environments, making it highly valuable to geomorphologists, glacial geologists, and sedimentologists, as well as applied sectors. The developed model has the potential to unlock numerous key research questions relating to past and present glacier behavior.

Hulskemper et al. report on a data-driven investigation and predictive modelling of Earth surface dynamics captured by high-resolution 4D remote sensing datasets. Their study shows how to integrate massive remote sensing observations to increase our process understanding in coastal morphodynamic research.

Grainsize distributions in rivers are highly variable while difficult to measure over long river reaches or entire river networks. Jordan Gilbert‘s work offers a statistical approach and numerical toolset to spatially estimate grainsize distributions.

A common perception is that changes in rock type (lithology) directly alter the long profile (or longtitudinal shape) of a river bed. However, this study finds that changes in lithology cannot be directly detected by looking at the long profile of a river, and the reason why it cannot be detected, is of broad interest to students of bedrock rivers and landscapes.

The paper by Paxman et al. presents a topographic analysis of the Gamburtsev Subglacial Mountains underneath the East Antarctic Ice Sheet. The authors analyse longitudinal valley profiles and apply concepts of fluvial landscape evolution to show that the subglacial landscape has a fluvial origin with a local glacial overprint. Based on channel steepness patterns, they determine the position of geological boundaries and assess the likely timing of tectonic uplift. Their analysis reveals that the South Pole Basin may contain sediment that could contain an archive of the formation and glaciation of the Gamburtsev Mountains.

Mountain streams comprise between 60 and 80% of total global river length. A primary trait of these streams are step-pool sequences. Whether the spacing of these features are regularly or randomly spaced is matter of debate. Erikson and Turowski resolve longstanding tension between the two competing models. Using data on natural, experimental, and numerically simulated step-pool sequences, they demonstrate that step-pool spacing rarely matches either assumption, but rather exists within a continuum. The findings of Erikson and Turowski challenge existing step-pool formation models, emphasize that efforts to replicate or install step-pools are fundamentally misguided when assuming regularity or randomness, and offer a potential alternative.