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Peatland surface motion is highly diagnostic of peatland condition. Interferometric Synthetic Aperture Radar (InSAR) can measure this at the landscape scale but requires ground validation. This necessitates upscaling from point to areal measures (80 × 90 m) but is hampered by a lack of data regarding the spatial variability of peat surface motion characteristics. Using a nested precise leveling approach within two areas of upland and low-lying blanket peatland within the Flow Country, Scotland, we examine the multiscale variability of peat surface motion. We then compare this with InSAR timeseries data. We find that peat surface motion varies at multiple scales within blanket peatland with decreasing dynamism with height above the water table e.g., hummocks < lawn < hollows. This trend is dependent upon a number of factors including ecohydrology, pool size/density, peat density, and slope. At the site scale motion can be grouped into central, marginal, and upland peatlands with each showing characteristic amplitude, peak timing, and response to climate events. Ground measurements which incorporate local variability show good comparability with satellite radar derived timeseries. However, current limitations of phase unwrapping in interferometry means that during an extreme drought/event InSAR readings can only qualitatively replicate peat movement in the most dynamic parts of the peatland e.g., pool systems, quaking bog.

We are communicating recent developments regarding the Surface motioN mAPPING (SNAPPING) service for the Sentinel-1 mission on the Geohazards Exploitation Platform (GEP) platform in support of the scientific community as well as of EO practitioners. We present the processing scheme adopted for the service and the designed implementation on the GEP, and we discuss in detail the user-defined processing parameters and service outputs. SNAPPING is offered through three independent services, namely the SNAPPING IFG for the generation of interferometric stacks, utilized consequently as input for the SNAPPING PSI Med and SNAPPING PSI Full services, which execute Persistent Scatterers Interferometry (PSI) analyses at medium and full resolutions, respectively. The inter-verification of the SNAPPING results was performed to underline the robustness of the provided measurements, and several showcases from diverse environments are demonstrated. The service aims to pave the way towards the improved acceptance of EO-hosted processing services and deeper community engagement, anticipating operational exploitation in response to geohazards.

Research on glacier movement is helpful for comprehensively understanding the laws behind this movement and can also provide a scientific basis for glacier change and analyses of the dynamic mechanisms driving atmospheric circulation and glacier evolution. Sentinel-1 series data were used in this study to retrieve the three-dimensional (3D) surface motion displacement of the Muz Taw glacier from 22 August 2017, to 17 August 2018. The inversion method of the 3D surface motion displacement of glaciers has been verified by the field measurement data from Urumqi Glacier No. 1. The effects of topographic factors, glacier thickness, and climate factors on the 3D surface displacement of the Muz Taw glacier are discussed in this paper. The results show that, during the study period, the total 3D displacement of the Muz Taw glacier was between 0.52 and 13.19 m, the eastward displacement was 4.27 m, the northward displacement was 4.07 m, and the horizontal displacement was 5.90 m. Areas of high displacement were mainly distributed in the main glacier at altitudes of 3300–3350 and 3450–3600 m. There were significant differences in the total 3D displacement of the Muz Taw glacier in each season. The displacement was larger in summer, followed by spring, and it was similar in autumn and winter. The total 3D displacement during the whole study period and in spring, summer, and autumn fluctuated greatly along the glacier centerline, while the change in winter was relatively gentle. Various factors such as topography, glacier thickness, and climate had different influences on the surface motion displacement of the Muz Taw glacier.

Synthetic Aperture Radar technology is highly convenient for monitoring the glacier surface motion in unfavorable areas due to its advantages of being independent of time and weather conditions. A novel glacier motion monitoring method based on the deep matching network (DMN) is proposed in this paper. The network learns the relationship between the glacier SAR image patch-pairs and the corresponding matching labels in an end-to-end manner. Unlike conventional methods that utilize shallow feature tracking, the DMN performs a similarity measurement of deep features, which comprises feature extraction and a metric network. Feature extraction adopts the framework of a Siamese neural network to improve the training efficiency and dense connection blocks to increase the feature utilization. In addition, a self-sample learning method is introduced to generate training samples with matching labels. The experiments are performed on simulated SAR images and real SAR intensity images of the Taku Glacier and the Yanong Glacier, respectively. The results confirm the superiority of the DMN presented in the paper over other methods, even in case of strong noise. Furthermore, a quantitative 2D velocity field of real glaciers is obtained to provide reliable support for high-precision, long-term and large-scale automatic glacier motion monitoring.

Flaps constitute a critical component within aircraft lift-enhancing systems, with their connecting pins inevitably subject to wear during operation. Current research on pin wear predominantly focuses on analytical and simulation domains, whilst testing is largely confined to component or sub-assembly levels. Simulated validation testing of flap pin wear failures at the component level or above remains exceptionally rare. To validate the impact of pivot clearance on flap motion characteristics following pin wear, a simulated wear fixture for flap pins was designed. A measurement and analysis apparatus for transient flap surface motion response was developed and validated through component-level flap failure simulation testing, providing a basis for assessing flap mechanism safety and reliability.

The Lianjiang Plain in China and ancient villages distributed within the plain are under the potential threat of surface motion change, but no effective monitoring strategy currently exists. Distributed Scatterer InSAR (DSInSAR) provides a new high-resolution method for the precise detection of surface motion change. In contrast to the first-generation of time-series InSAR methodology, the distributed scatterer-based method focuses both on pointwise targets with high phase stability and distributed targets with moderate coherence, the latter of which is more suitable for the comprehensive environment of the Lianjiang Plain. In this paper, we present the first study of surface motion change detection in the Lianjiang Plain, China. Two data stacks, including 54 and 29 images from Sentinel-1A adjacent orbits, are used to retrieve time-series surface motion changes for the Lianjiang Plain from 2015 to 2018. The consistency of measurement has been cross-validated between adjacent orbit results with a statistically significant determination coefficient of 0.92. The temporal evolution of representative measuring points indicates three subzones with varied surface patterns: Eastern Puning (Zone A) in a slight elastic rebound phase with a moderate deformation rate (0–40 mm/year), Chaonan (Zone B) in a substantial subsidence phase with a strong deformation rate (−140–0 mm/year), and Chaoyang (Zone C) in a homogeneous and stable situation (−10–10 mm/year). The spatial distribution of these zones suggests a combined change dynamic and a strong concordance of factors impacting surface motion change. Human activities, especially groundwater exploitation, dominate the subsidence pattern, and natural conditions act as a supplementary inducement by providing a hazard-prone environment. The qualitative and quantitative analysis of spatial and temporal details in this study provides a basis for systematic surface motion monitoring, cultural heritage protection and groundwater resources management.

Untethered magnet‐driven microrobots play an increasingly important role in various biomedical applications. Incorporating bionic technology into microrobot design is an emerging way to improve the work efficiency of microrobots. Herein, a magnetically powered and frictional anisotropy‐based microwalker that can be potentially used in in vivo nonliquid‐filled environment is proposed. The microwalker is constructed by two rigid segments with an equal length of 70 μm, connected by a rigid joint. Parallel gecko setae‐like tentacles are placed at the bottom of the segments as contact feet to generate friction with the contact surface. The microwalker is integrally fabricated from biocompatible materials with 3D laser lithography based on two‐photon polymerization. The microwalker can be well controlled to move in low‐Reynolds (Re)‐number regimes under an external oscillating magnetic field. In addition to moving in a liquid environment as existing microswimmers, the microwalker can move in surface in a nonliquid‐filled environment. It can also climb the slope driven by the planar magnetic field only. Several experiments were conducted to demonstrate good motion capability of the microwalker. This study provides a new solution to microrobot design for future biomedical applications. Herein, a magnetically powered and frictional anisotropy‐based microwalker with bioinspired contact feet is proposed. The microwalker is constructed by two rigid segments fabricated with 3D laser lithography. It can be well controlled to move in low‐Reynolds‐number regimes under an external oscillating magnetic field to achieve surface motion in nonliquid‐filled environment and climb the slope.

Significant differences exist in the ground response of saturated and unsaturated deposits to earthquakes, but few relevant studies exist on strong ground motion in saturated loess. We have selected three loess sites that are highly affected by earthquake‐induced liquefaction hazards, analyzed the nonlinear characteristics of the ground motion response of saturated loess sites through extensive field tests, laboratory experiments, and analytical ground motion response calculations, and compared them with the unsaturated site conditions to reveal the special strong ground motion response characteristics of saturated loess sites. The results show that the PGA of surface ground motion in the Guyuan and Minxian sites is significantly reduced compared with the PGA of input ground motion, and the PGA of surface ground motion in the Tianshui site is slightly increased compared with the PGA of input ground motion. The frequency corresponding to the peak of the Fourier spectrum of the two sites in Guyuan and Minxian decreased significantly, and the frequency corresponding to the peak of the Fourier spectrum of ground motion in the Tianshui site increased slightly. Compared with unsaturated loess, the dynamic stiffness of saturated loess decreases, and the dynamic shear modulus ratio and damping ratio change significantly under high dynamic shear strain. These changes lead to a weakened ground vibration response at the surface, especially at high PGA inputs, highlighting the key differences in ground motions between saturated and unsaturated loess sites. In addition, the dominant frequency of surface motion is significantly lower at saturated loess sites, increasing the risk of site damage during earthquakes. These results emphasize the complex interplay between loess saturation and the dynamic response to earthquakes and demonstrate the need for targeted geotechnical assessment and design in earthquake‐prone areas of the Loess Plateau.

Dynamic topography is a well-established consequence of global geodynamic models of mantle convection with horizontal dimensions of >1000 km and amplitudes up to 2 km. Such physical models guide the interpretation of geological records on equal dimensions. Continent-scale geological maps therefore serve as reference frames of choice to visualize erosion/non-deposition as a proxy for long-wavelength, low-amplitude vertical surface motion. At a resolution of systems or series, such maps display conformable and unconformable time boundaries traceable over hundreds to thousands of kilometres. Unconformable contact surfaces define the shape and size of time gap (hiatus) in millions of years based on the duration of time represented by the missing systems or series. Hiatus for a single system or series base datum diminishes laterally to locations (anchor points) where it is conformable at the mapped resolution; it is highly dependent upon scale. A comparison of hiatus area between two successive system or series boundaries yields changes in location, shape, size and duration, indicative of the transient nature of vertical surface motion. As a single-step technique, it serves as a quantitative proxy for palaeotopography that can be calibrated using other geological data. The tool magnifies the need for geological mapping at the temporal resolution of stages, matching process rates. The method has no resolving power within conformable regions (basins) but connects around them. When applied to marine seismic sections that relate to rock record, not to time, biostratigraphic and radiometric data from deep wells are needed before hiatus areas – that relate to time – can be mapped.

Wind-generated ocean waves drive important coastal processes that determine flooding and erosion. Ocean warming has been one factor affecting waves globally. Most studies have focused on studying parameters such as wave heights, but a systematic, global and long-term signal of climate change in global wave behavior remains undetermined. Here we show that the global wave power, which is the transport of the energy transferred from the wind into sea-surface motion, has increased globally (0.4% per year) and by ocean basins since 1948. We also find long-term correlations and statistical dependency with sea surface temperatures, globally and by ocean sub-basins, particularly between the tropical Atlantic temperatures and the wave power in high south latitudes, the most energetic region globally. Results indicate the upper-ocean warming, a consequence of anthropogenic global warming, is changing the global wave climate, making waves stronger. This identifies wave power as a potentially valuable climate change indicator.