Satellite gravity sees ice age footprints; using monthly maps of gravity field variations to find the geometry of ancient ice sheets

Superconducting persistent-current qubit

The effect of GIA observables in the determination of upper mantle structures

Maps4Science - National Roadmap for Large-Scale Research Facilities 2011 (NWO Application form)

The Netherlands is historically known as one of worlds' best-measured countries. It is continuing this tradition today with unequalled new datasets, such as the nationwide large-scale topographic map, our unique digital height map (nationwide coverage; ten very accurate 3D points for every Dutch m2) and a range of public and private collections...

GRACE gravity observations constrain Weichselian ice thickness in the Barents Sea

The Barents Sea is subject to ongoing postglacial uplift since the melting of the Weichselian ice sheet that covered it. The regional ice sheet thickness history is not well known because there is only data at the periphery due to the locations of Franz Joseph Land, Svalbard, and Novaya Zemlya surrounding this paleo ice sheet. We show that the...

Detectability of groundwater storage change within the Great Lakes Water Basin using GRACE

Groundwater is a primary hydrological reservoir of the Great Lakes Water Basin (GLB), which is an important region to both Canada and US in terms of culture, society and economy. Due to insufficient observations, there is a knowledge gap about groundwater storage variation and its interaction with the Great Lakes. The objective of this study is...

Antarctic outlet glacier mass change resolved at basin scale from satellite gravity gradiometry

The orbit and instrumental measurement of the Gravity Field and Steady State Ocean Circulation Explorer (GOCE) satellite mission offer the highest ever resolution capabilities for mapping Earth's gravity field from space. However, past analysis predicted that GOCE would not detect changes in ice sheet mass. Here we demonstrate that GOCE gravity...

Improved GRACE regional mass balance estimates of the Greenland Ice Sheet cross-validated with the input-output method (discussion paper)

In this study, we use satellite gravimetry data from the Gravity Recovery and Climate Experiment (GRACE) to estimate regional mass changes of the Greenland ice sheet (GrIS) and neighbouring glaciated regions using a least-squares inversion approach. We also consider results from the input-output method (IOM) that quantifies the difference...

Glacial isostatic adjustment model with composite 3-D Earth rheology for Fennoscandia

Models for glacial isostatic adjustment (GIA) can provide constraints on rheology of the mantle if past ice thickness variations are assumed to be known. The Pleistocene ice loading histories that are used to obtain such constraints are based on an a priori 1-D mantle viscosity profile that assumes a single deformation mechanism for mantle rocks...

The measurement of house prices: A review of the sale price appraisal ratio method

The sale price appraisal ratio (SPAR) method has been applied in a number of countries to construct house price indexes. This paper reviews the statistical and index number properties of the SPAR approach. Three types of SPAR indexes are distinguished: a weighted index, which aims at tracking the price change of the stock of owner-occupied...

Windows of opportunity for salt marsh vegetation establishment on bare tidal flats: The importance of temporal and spatial variability in hydrodynamic forcing

Understanding the mechanisms limiting and facilitating salt marsh vegetation initial establishment is of widespread importance due to the many valuable services salt marsh ecosystems offer. Salt marsh dynamics have been investigated by many previous studies, but the mechanisms that enable or disable salt marsh initial establishment are still...

Glacial isostatic adjustment in the static gravity field of Fennoscandia

In the central part of Fennoscandia, the crust is currently rising, because of the delayed response of the viscous mantle to melting of the Late Pleistocene ice sheet. This process, called Glacial Isostatic Adjustment (GIA), causes a negative anomaly in the present-day static gravity field as isostatic equilibrium has not been reached yet....

On the postprocessing removal of correlated errors in GRACE temporal gravity field solutions

We revisit the empirical moving window filtering method of Swenson and Wahr (Geophys Res Lett 33:L08402, 2006) and its variants, Chambers (Geophys Res Lett 33:L17603, 2006) and Chen et al. (Geophys Res Lett 34: L13302, 2007), for reducing the correlated errors in the Stokes coefficients (SCs) of the spherical harmonic expansion of the GRACE...

Effect of GIA models with 3D composite mantle viscosity on GRACE mass balance estimates for Antarctica

Seismic data indicate that there are large viscosity variations in the mantle beneath Antarctica. Consideration of such variations would affect predictions of models of Glacial Isostatic Adjustment (GIA), which are used to correct satellite measurements of ice mass change. However, most GIA models used for that purpose have assumed the mantle to...

Ocean contribution to co-seismic crustal deformation and geoid anomalies: Application to the 2004 December 26 Sumatra-Andaman earthquake

Large earthquakes do not only heavily deform the crust in the vicinity of the fault, they also change the gravity field of the area affected by the earthquake due to mass redistribution in the upper layers of the Earth. Besides that, for sub-oceanic earthquakes deformation of the ocean floor causes relative sea level changes and mass...

A house price index based on the SPAR method

Within the European Union there has been a push to provide European governments and the European Central Bank with the statistics they need for monitoring the owneroccupied sector. This paper reports on the results of a project to develop a house price index for the Netherlands. From January 2008, Kadaster, the Dutch land registry office, and...

Good long-term outcomes of the hip Chiari osteotomy in adolescents and adults with hip dysplasia: a systematic review

BACKGROUND AND PURPOSE:   The Chiari osteotomy was a regular treatment for developmental hip dysplasia before it became mostly reserved as a salvage therapy. However, the long-term survival of the Chiari osteotomy has not been systematically investigated. We investigated the survival time of the Chiari osteotomy until conversion to total hip...

Quantifying Bed Level Change at the Transition of Tidal Flat and Salt Marsh: Can We Understand the Lateral Location of the Marsh Edge?

Bed level dynamics at the interface of the salt marsh and tidal flat have been highlighted as a key factor connecting the long-term biogeomorphological development of the marsh to large-scale physical forcing. Hence, we aim to obtain insight into the factors confining the location of the marsh edge (i.e., boundary between tidal flat and salt...