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Space gravity missions have enabled the quantification of the mass component of sea‐level rise over the past two decades. Barystatic sea‐level rise is predominantly driven by melting polar ice sheets and mountain glaciers. However, continental hydrological processes also contribute to global sea level change at significant magnitudes. We show that for most coastal areas in low‐to‐mid latitudes, up to half of manometric sea‐level rise is due to changes in water storage in ice‐free continental regions. At other locations the direct attraction effect of anthropogenic pumping of groundwater over the duration of the Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow‐On (GRACE‐FO) mission offsets sea‐level rise from ice sheet and glacier melt. If these trends in continental hydrological storage were to slow or stop, these regions would experience greatly accelerated sea‐level rise, posing a risk to coastal settlements and infrastructure, however, for most coastal communities current rates of sea‐level rise would be significantly reduced. Plain Language Summary: It is well understood that melting of polar ice sheets and mountain glaciers cause increases in ocean mass, leading to a corresponding rise in global sea level. What is not as obvious is that multi‐year changes in the storage of water on continents not covered by ice also contribute significantly to changes in global sea level. Over recent years and in some locations, the magnitude of these "continental hydrology" contributions to sea level changes have been comparable to the contributions of the ice‐covered regions. In some cases, the former have offset the ice sheet contributions, thus reducing regional sea‐level rise to substantially smaller magnitudes. Through an analysis of space gravity data, we have quantified the effects of continental hydrology on regional sea level and show that changes caused both naturally (e.g., through La Niña events) and through anthropogenic activities (e.g., extraction of groundwater) can increase or decrease regional sea level by significant amounts. Key Points: Exchange of water between continents and oceans causes global sea level change at rates comparable to the contributions of ice sheetsThe direct gravitational attraction effect on local sea level is of a larger magnitude than the far‐field sea level changesInter‐annual continental hydrology signal impacts on local sea level have negated the impacts of melting polar ice sheets in some locations [ABSTRACT FROM AUTHOR]

Editors of JGR‐Solid Earth express their appreciation to those who served as peer reviewers for the journal in 2022. Plain Language Summary: The editorial board of JGR‐Solid Earth thanks those who served as peer reviewers for the journal in 2022. Key Points: Thank you to the reviewers of articles submitted to JGR‐Solid Earth [ABSTRACT FROM AUTHOR]

Global Positioning System (GPS) deformation measurements were combined with groundwater level data to examine the spatiotemporal variability of groundwater storage in the Lachlan catchment located in central New South Wales (Australia). After correcting for effects of glacial isostatic adjustment, non‐tidal oceanic and atmospheric loading as well as hydrologic loading using existing models, we show that the seasonal and interannual variability of ground deformation and hydraulic head level data, extracted using wavelet time‐frequency analysis, exhibits an in‐phase behavior, indicating that the observed surface deformation is the poroelastic response to groundwater pressure change in aquifer system. Combination of GPS displacement and groundwater level change enables the estimation of elastic skeletal specific storage coefficients, which were then used for estimating groundwater storage changes. The estimated groundwater storage changes clearly reflect the four climate events of the Lachlan catchment since 1996: (a) the Millennium drought over 1996–2009, (b) the 2011–2012 La Nina and two significant floods in 2012 and 2016, (c) the drought conditions from mid‐2017 to late‐2019, and (d) the return of La Nina conditions since early 2020. We also found annual and long‐term groundwater storage variations of respectively ∼25±2.7GL $\sim 25\,\pm \,2.7\,\mathrm{G}\mathrm{L}$ and ∼−5±0.57GL/yr $\sim -5\,\pm \,0.57\,\mathrm{G}\mathrm{L}/\mathrm{y}\mathrm{r}$ over the period 2012–2021. Moreover, we show that groundwater level fluctuations can be predicted from GPS displacement measurements and storage coefficients with sufficient accuracy (80% correlation and 70% RMS reduction when compared in terms of seasonal cycle). This study provides essential information that can contribute to future groundwater planning, management, and control over the Australian continent. Plain Language Summary: Groundwater extraction or recharge changes the height of the Earth's surface, which can be obtained from displacement measurements derived from Global Positioning System (GPS). We combined the GPS displacement measurements over the Lachlan aquifer, located in central New South Wales (Australia), with the groundwater level change to study groundwater storage variation. The estimated groundwater storage changes reflect the major climate conditions over the area since 1996 such as the Millennium drought and the significant La Nina events in 2011 and 2020. We further analyze the aquifer response to the rainfall and found a delay ranging from 3 weeks to 2 months between the rainfall and groundwater wells levels, depending on the depth of the aquifer. Key Points: We estimate groundwater storage variation by combining Global Positioning System (GPS) vertical displacement and groundwater level dataInterannual variability measured by GPS vertical deformation is mainly driven by poroelasticity effect due to groundwater storage changesThe method is able to model seasonal groundwater level fluctuation using GPS displacement measurement and storage coefficient of the aquifer [ABSTRACT FROM AUTHOR]

Editors of JGR‐Solid Earth express their appreciation to those who served as peer reviewers for the journal in 2021. Plain Language Summary: The editorial board of JGR‐Solid Earth thanks those who served as peer reviewers for the journal in 2021. Key Points: Thank you to the reviewers of articles submitted to JGR‐Solid Earth [ABSTRACT FROM AUTHOR]

Members of the editorial board of JGR‐Solid Earth express their appreciation to those who served as peer reviewers for the journal in 2020. Plain Language Summary: The editorial board of JGR‐Solid Earth thanks those who served as peer reviewers for the journal in 2020. Key Points: Thank you to the reviewers of articles submitted to JGR‐Solid Earth [ABSTRACT FROM AUTHOR]

Key Point: Thank you to the reviewers of articles submitted to Solid Earth [ABSTRACT FROM AUTHOR]

Similar to the construction of physical buildings, the scientific edifice requires solid components of data, theory, and methodology at each phase of the "construction." The peer review process provides the necessary "inspection" and the assurance that every step of the construction is solid, particularly in regard to the proper use of the scientific method. The peer‐review process helps improve the published work by providing constructive suggestions and by safe‐guarding against scientific work, later found to be built on shaky foundations. Because no single scientist has intimate knowledge of today's many aspects of Solid Earth Sciences, we rely on each other's expertise to serve as unbiased "inspectors" of published articles. Your considerable time and effort, spent reviewing JGR‐Solid Earth manuscript(s) during 2018, are sincerely appreciated by our editorial board and, more importantly, by the Solid Earth Science community at large. Thank you. Key Points: Thank you to the 2018 peer reviewers [ABSTRACT FROM AUTHOR]

The network effect is the error associated with the subsampling of the Earth surface by space geodetic networks. It is an obstacle toward the precise measurement of geocenter motion, that is, the relative motion between the center of mass of the Earth system and the center of figure of the Earth surface. In a complementary paper, we proposed a theoretical approach to estimate the magnitude of this effect from the displacement fields predicted by geophysical models. Here we evaluate the effectiveness of our estimate for two illustrative physical processes: coseismic displacements inducing instantaneous changes in the Helmert parameters and elastic deformation due to surface water movements causing secular drifts in those parameters. For the first, we consider simplified models of the 2004 Sumatra-Andaman and the 2011 Tōhoku-Oki earthquakes, and for the second, we use the observations of the Gravity Recovery and Climate Experiment, complemented by an ocean model. In both case studies, it is found that the magnitude of the network effect, even for a large global network, is often as large as the magnitude of the changes in the Helmert parameters themselves. However, we also show that our proposed modification to the definition of the center of network frame to include weights proportional to the area of the Earth surface that the stations represent can significantly reduce the network effect in most cases. [ABSTRACT FROM AUTHOR]

Geophysical models and their interpretations of several processes of interest, such as sea level rise, postseismic relaxation, and glacial isostatic adjustment, are intertwined with the need to realize the International Terrestrial Reference Frame. However, this realization needs to take into account the geocenter motion, that is, the motion of the center of figure of the Earth surface, due to, for example, deformation of the surface by earthquakes or hydrological loading effects. Usually, there is also a discrepancy, known as the network effect, between the theoretically convenient center of figure and the physically accessible center of network frames, because of unavoidable factors such as uneven station distribution, lack of stations in the oceans, disparity in the coverage between the two hemispheres, and the existence of tectonically deforming zones. Here we develop a method to estimate the magnitude of the network effect, that is, the error introduced by the incomplete sampling of the Earth surface, in measuring the geocenter motion, for a network of space geodetic stations of a fixed size N. For this purpose, we use, as our proposed estimate, the standard deviations of the changes in Helmert parameters measured by a random network of the same size N. We show that our estimate scales as [ABSTRACT FROM AUTHOR]

The accuracy of global water balance estimates is limited by the lack of observations at large scale and the uncertainties of model simulations. Global retrievals of terrestrial water storage (TWS) change and soil moisture (SM) from satellites provide an opportunity to improve model estimates through data assimilation. However, combining these two data sets is challenging due to the disparity in temporal and spatial resolution at both vertical and horizontal scale. For the first time, TWS observations from the Gravity Recovery and Climate Experiment (GRACE) and near-surface SM observations from the Soil Moisture and Ocean Salinity (SMOS) were jointly assimilated into a water balance model using the Ensemble Kalman Smoother from January 2010 to December 2013 for the Australian continent. The performance of joint assimilation was assessed against open-loop model simulations and the assimilation of either GRACE TWS anomalies or SMOS SM alone. The SMOS-only assimilation improved SM estimates but reduced the accuracy of groundwater and TWS estimates. The GRACE-only assimilation improved groundwater estimates but did not always produce accurate estimates of SM. The joint assimilation typically led to more accurate water storage profile estimates with improved surface SM, root-zone SM, and groundwater estimates against in situ observations. The assimilation successfully downscaled GRACE-derived integrated water storage horizontally and vertically into individual water stores at the same spatial scale as the model and SMOS, and partitioned monthly averaged TWS into daily estimates. These results demonstrate that satellite TWS and SM measurements can be jointly assimilated to produce improved water balance component estimates. [ABSTRACT FROM AUTHOR]

The Murray-Darling Basin in southeast Australia is experiencing one of the most severe droughts observed recently in the world, driven by several years of rainfall deficits and record high temperatures. This paper provides new basin-scale observations of the multiyear drought, integrated to a degree rarely achieved on such a large scale, to assess the response of water resources and the severity of the drought. A combination of Gravity Recovery and Climate Experiment (GRACE) data with in situ and modeled hydrological data shows the propagation of the water deficit through the hydrological cycle and the rise of different types of drought. Our observations show the rapid drying of soil moisture and surface water storages, which reached near-stationary low levels only ∼2 years after the onset of the drought in 2001, with a loss of ∼80 and ∼12 km3 between January 2001 and January 2003, respectively. The multiyear drought has led to the almost complete drying of surface water resources which account for most of the water used for irrigation and domestic purposes. High correlation between observed groundwater variations and GRACE data substantiates the persistent reduction in groundwater storage, with groundwater levels still declining 6 years after the onset of the drought (groundwater loss of ∼104 km3 between 2001 and 2007). The hydrological drought continues even though the region returned to average annual rainfall during 2007. [ABSTRACT FROM AUTHOR]

The editors of JGR: Solid Earth announce that Plain Language Summaries will be required for all manuscripts. Plain Language Summary: All manuscripts published in JGR‐Solid Earth will include a Plain Language Summary. Key Point: An announcement that Plain Language Summaries will be required for all articles published in the journal [ABSTRACT FROM AUTHOR]