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Crustal deformation and seismic activity in the Levant is mainly related to the interplate Dead Sea Fault (DSF) and the intraplate Carmel–Gilboa Fault System (CGFS). In this study, we analyze the interseismic deformation along these fault systems using 23 years of Global Positioning System (GPS) measurements obtained from 209 campaign and 60 continuous stations. This GPS data set is the longest record and the densest data set for the DSF, the CGFS, and the Levant region. We use this data set to investigate the spatial variations of slip and creep rates along the southern and central sections of the DSF and the CGFS. Our inversion model results indicate that part of the tectonic motion is transferred from the DSF to the CGFS. We find that the left‐lateral strike‐slip motion along the DSF decreases in a rate of 0.9 ± 0.4 mm/year, from 4.8 ± 0.3 mm/year south to the intersection with the CGFS to 3.9 ± 0.4 mm/year north to this intersection. Along the CGFS, the left‐lateral strike‐slip motion ranges between ∼0.3 and 0.5 mm/year and the extension rate between ∼0.6 and 0.7 mm/year, indicating a total slip rate vector of 0.8 ± 0.4 mm/year in the DSF direction, in agreement with the reduction of slip rate along the DSF near the intersection with the CGFS. Shallow creep is found along the southern and central sections of the Dead Sea basin and the northern Jordan Valley section of the DSF, with creep rates of 3.4 ± 0.4 and 2.3 ± 0.4 mm/year, respectively. These creeping sections were identified as areas with thick Halite layers at the shallow subsurface. We suggest that shallow creep behavior along the DSF is govern by the presence and mechanical properties of the Halite, which probably allows plastic deformation and the transition to velocity strengthening at the shallow subsurface and promotes creep. Plain Language Summary: The variations in slip and creep rates along major faults and the distribution of strain rates are key factors in seismic hazard assessment. In this study, we address these factors for the Dead Sea Fault (DSF) and the Carmel–Gilboa Fault System (CGFS) using the longest record and the densest Global Positioning System (GPS) measurements for the Levant region. The DSF is the boundary between Arabia and Sinai tectonic plates, and the CGFS is a major intraplate fault system within the Sinai plate. We used 23 years of GPS measurements obtained from 269 stations. We find that the left‐lateral strike‐slip motion along the southern DSF is ∼5 mm/year and decreases to ∼4 mm/year north to the intersection with the CGFS. Along the CGFS, a total slip rate of ∼0.8 mm/year in the DSF direction is found. Shallow creep is found along the southern and central sections of the Dead Sea basin and the northern Jordan Valley section of the DSF. These creeping sections were identified as areas with thick salt layers at the shallow subsurface. We therefore suggest that the shallow creep along the DSF is due to the salt behavior, which can deform plastically and creep. Key Points: The interseismic deformation along the Dead Sea Fault (DSF) and the Carmel–Gilboa Fault System (CGFS) is analyzed using 23 years of dense Global Positioning System (GPS) measurementsA decrease in the slip rate along the DSF due to slip partitioning with the CGFS is found near the intersection of these faultsShallow creep is found along the southern and central sections of the Dead Sea basin and the northern Jordan Valley section of the DSF [ABSTRACT FROM AUTHOR]

Monitoring vertical land motions (VLMs) at the level of 0.1 mm/yr remains one of the most challenging scientific applications of global navigation satellite systems (GNSS). Such small rates of change can result from climatic and tectonic phenomena, and their detection is important to many solid Earth‐related studies, including the prediction of coastal sea‐level change and the understanding of intraplate deformation. Reaching a level of precision allowing to detect such small signals requires a thorough understanding of the stochastic variability in GNSS VLM time series. This paper investigates how the aperiodic part of non‐tidal atmospheric and oceanic loading (NTAOL) deformations influences the stochastic properties of VLM time series. Using the time series of over 10,000 stations, we describe the impact of correcting for NTAOL deformation on 5 complementary metrics, namely: the repeatability of position residuals, the power‐spectrum of position residuals, the estimated time‐correlation properties, the corresponding velocity uncertainties, and the spatial correlation of the residuals. We show that NTAOL deformations cause a latitude‐dependent bias in white noise plus power‐law model parameter estimates. This bias is significantly mitigated when correcting for NTAOL deformation, which reduces velocity uncertainties at high latitudes by 70%. Therefore, removing NTAOL deformation before the statistical analysis of VLM time series might help to detect subtle VLM signals in these areas. Our spatial correlation analysis also reveals a seasonality in the spatial correlation of the residuals, which is reduced after removing NTAOL deformation, confirming that NTAOL is a clear source of common‐mode errors in GNSS VLM time series. Plain Language Summary: Monitoring vertical land motions (VLMs) at the level of 0.1 mm/yr remains one of the most challenging scientific applications of global navigation satellite systems (GNSS). Such small rates of change can result from climatic and tectonic phenomena, and their detection is important to the prediction of coastal sea‐level change and the understanding of deformation processes acting within tectonic plates. In this paper, we investigate to what extent accounting for the deformation of the Earth's crust due to changes in the distribution of the atmospheric and the oceanic pressure helps to detect small vertical ground deformation. By analyzing the data from over 10,000 globally distributed GNSS stations, we show that accounting for such atmospheric and oceanic deformation can reduce by 70% the uncertainty on the vertical velocity of GNSS stations at high latitudes, which could, for instance, improve sea‐level change monitoring in these areas. Key Points: Non‐tidal atmospheric and oceanic loading (NTAOL) deformations cause a latitudinal bias in parameter estimates of the white + power‐law noise model usually describing global navigation satellite systems (GNSS) time seriesRemoving NTAOL deformations corrects the latitudinal bias and dramatically reduces station velocity uncertainties at high latitudesNTAOL deformations also introduce a seasonal spatial correlation in GNSS vertical land motion time series [ABSTRACT FROM AUTHOR]