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Geodetically‐derived deformation rates are sometimes used to infer seismic hazard, implicitly assuming that short‐term (annual‐decadal) deformation is representative of longer‐term deformation. This is despite geological observations indicating that deformation/slip rates are variable over a range of timescales. Using geodetic data from 2016 to 2021, we observe an up to 7‐fold increase in vertical deformation rate in mid‐2019 across the Pisia‐Skinos normal fault in Greece. We hypothesize that this deformation is aseismic as there is no temporally correlated increase in the earthquake activity (M > 1). We explore four possible physical mechanisms, and our preferred hypothesis is that the transient deformation is caused by centimeter‐scale slip in the upper 5 km of the Pisia fault zone. This is the first observation of shallow tectonic (i.e., not related to human activities) aseismic deformation on a normal fault globally. Our results suggest that continental normal faults can exhibit variable deformation over shorter timescales than previously observed, and thus care should be taken when utilizing geodetic rates to quantify seismic hazard. Plain Language Summary: Slip rates of active faults are used in seismic hazard assessment to infer the frequency of damaging earthquakes. However slip rates are known to be variable when measured using different methodologies (e.g., geodesy, geomorphology) and timescales (years to millennia) for many types of faults in a range of tectonic settings. Hence we need to observe slip rates for different time scales and try to understand the mechanism(s) that cause slip rates to vary. In this paper, we present observations of vertical deformation around an active normal fault in the Gulf of Corinth, Greece. We see that the deformation is non‐uniform during 2016–2021 (the time period of data availability), and we analyze the data to find that the deformation rate increased in mid‐2019. To try and understand the physical mechanism that may have caused this increase in deformation rate, we use simple modeling to test four different hypotheses. We find that the best fit to the observations is for centimeters of slip occurring on shallowest few kilometers of the fault. Our results highlight the importance of understanding short‐term (annual‐decadal) processes happening on active faults, and the potential pitfalls of using slip rates measured over short‐timescales to infer seismic hazard. Key Points: Spatial variations in vertical ground motion (uplift/subsidence) correlate with the mapped trace of the Pisia‐Skinos fault in GreeceThe ground deformation is non‐uniform over the 6 years studied, and shows an up to 7× increase in rate, lasting at least 3 yearsThis transient interseismic deformation is hypothesized to be caused by shallow aseismic centimeter‐scale slip on the Pisia‐Skinos fault [ABSTRACT FROM AUTHOR]

Abstract This paper assesses the suitability of the early warning systems and post-disaster housing for the elderly population of Japan in the immediate and transitional recovery phase of the 2011 Great East Japan Earthquake and Tsunami. Written questionnaires and informal group interviews were conducted with residents of six temporary housing complexes in Miyagi and Iwate three and half years after the disaster. The median age of participants was 70, with an age range of 48 years. We assess rates of warning receipt in the immediacy of the event, evacuation actions thereafter, and the experience of living in temporary accommodation. 81% of those surveyed received at least one type of earthquake or tsunami warning, the most common being an audio mobile phone (AMP) message (which is received through a smart phone), heard by 45% of the sample. Radio, siren, and AMP notifications were most effective at informing the elderly overall. 84% of recipients took action in response to a tsunami warning, with 79% of respondents evacuating their homes prior to the arrival of the first wave. During the transitional phase of recovery, residents within temporary housing highlighted issues including a lack of floor space, poor thermal insulation, solitary living environments, and reduced privacy, which lead to stressed domestic relationships within families and social groups. Recommendations are made to consider the elderly to a greater degree in planning for the early warning and immediate phases of disaster, and throughout the long-term recovery process, in order to improve their psychological and physiological well-being. [ABSTRACT FROM AUTHOR]

This paper presents city dwellers and local authorities with questions that international humanitarian organisations (IHOs) may not ask after massive housing destruction. We examine Japan's transitional shelter strategy following the 2011 Great East Japan Earthquake and Tsunami (GEJET) against these questions: who decides when and where to build housing; what is built, how and by whom; who finances, owns or rents; and how might such conditions affect disaster response? The analysis puts strategy in context by combining data on housing, subsidies and insurance, rather than presenting shelter delivery in isolation. In Japan, systemic housing-related vulnerabilities preceded the GEJET; shelter was a time-limited accommodation service; and cash hand-outs were not a cultural norm, not intended to be sufficient and never equivalent to the cost of temporary housing units. We argue that such analysis is needed to challenge IHO thinking and uncover specific historical, regulatory and personal housing trajectories following a disaster. [ABSTRACT FROM AUTHOR]