We use broadband seismic recordings to trace the dynamic process of the deep‐seated Akatani landslide that occurred on the Kii Peninsula, Japan, which is one of the best recorded large slope failures. Combining analyses of the seismic records with precise topographic surveys done before and after the event, we can resolve a detailed time history of the mass movement. During 50 s of the large landslide, we observe a smooth initiation, acceleration with changes in basal friction, and reversal of the momentum when the mass collides with the opposite valley wall. Of particular importance is the determination of the dynamic friction during the landslide. The coefficient of friction is estimated to be 0.56 at the beginning of the event and drops to 0.38 for most of the sliding. The change in the frictional level on the sliding surface may be due to liquefaction or breaking of rough patches and contributes to the extended propagation of the large landslide.

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Large deep‐seated landslides occurred in Nara, Wakayama, and Mie prefectures of western Japan when Typhoon Talas passed through the region on September 3–4, 2011. Signals of large landslides have been recorded by seismic networks around the world, and overall force estimates have been previously determined for large landslides using long‐period waves. This study focuses on the high‐frequency waveforms and presents signals of 18 landslides caused by Typhoon Talas (2011). The location of the landslides can be determined by a seismological back‐projection technique and these locations correlate with the observed surface features. We have found that the volumes of the landslide correlated with an energy parameter derived from the seismic records.

Global cooling in intermediate glacial climate with northern ice sheets preconditions climatic instability with bipolar seesaw.

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A first international (36)Cl interlaboratory comparison has been initiated. Evaluation of the final results of the eight participating accelerator mass spectrometry (AMS) laboratories on three synthetic AgCl samples with (36)Cl/Cl ratios at the 10(-11), 10(-12), and 10(-13) level shows no difference in the sense of simple statistical significance. However, more detailed statistical analyses demonstrate certain interlaboratory bias and underestimation of uncertainties by some laboratories. Following subsequent remeasurement and reanalysis of the data from some AMS facilities, the round-robin data indicate that (36)Cl/Cl data from two individual AMS laboratories can differ by up to 17%. Thus, the demand for further work on harmonising the (36)Cl-system on a worldwide scale and enlarging the improvement of measurements is obvious.

A precursory sequence of repeating earthquakes was recorded before the Rausu landslide in Hokkaido, Japan, on 24 April 2015. There were two seismic sequences with each consisting of very similar waveforms and leading up to significant landslide movements. The nearly identical waveform shapes indicate similar source locations and mechanisms, so repeated events originated on a particular small area. This sequence is interpreted as stick‐slip movement on a small patch leading up to the larger landslide failure. Our observations show that heterogeneous structure, such as asperities on the slip surface, can play an important role in the initiation of landslides, adding a new aspect to the conventional understanding of mechanisms controlling large mass movements.