A5112517564- Geophysics and Gravity Measurements
- GNSS positioning and interference
- Inertial Sensor and Navigation
- Ionosphere and magnetosphere dynamics
- Oceanographic and Atmospheric Processes
- Geomagnetism and Paleomagnetism Studies
- Ocean Waves and Remote Sensing
- Space Satellite Systems and Control
- Astronomical Observations and Instrumentation
- Solar and Space Plasma Dynamics
- Methane Hydrates and Related Phenomena
- Space exploration and regulation
- Spacecraft Design and Technology
- Climate variability and models
- Meteorological Phenomena and Simulations
- earthquake and tectonic studies
- Advanced Frequency and Time Standards
- Astro and Planetary Science
- Planetary Science and Exploration
- Target Tracking and Data Fusion in Sensor Networks
- Precipitation Measurement and Analysis
- Spacecraft and Cryogenic Technologies
- Satellite Image Processing and Photogrammetry
- Arctic and Antarctic ice dynamics
- Soil Moisture and Remote Sensing
Jet Propulsion Laboratory
2012-2024
California Institute of Technology
2002-2021
Given the considerable range of applications within European Union Copernicus system, sustained satellite altimetry missions are required to address operational, science and societal needs. This article describes Sentinel-6 mission that is designed provide precision sea level, surface height, significant wave inland water heights other products tailored operational services in ocean, climate, atmospheric land Services. provides enhanced continuity very stable time series mean level...
Almost 9 years of sea surface height observations from the TOPEX/Poseidon (T/P) satellite altimetry mission are used to observe geocentric pole tide deformations surface. If oceans assumed have an equilibrium response, then altimeters effectively equipotential that is associated with solid Earth and ocean deformations. The long‐wavelength component at Chandler wobble period observed T/P be consistent theoretical self‐consistent response tide. explains 70% variance in degree 2 order 1...
The U.S./French Jason-1 satellite is carrying a state-of-the-art GPS receiver to support precise orbit determination (POD) requirements. performance of the "BlackJack" was strongly reflected in early POD results from mission, enabling radial accuracies 1–2 cm soon after satellite's 2001 launch. We have made further advances GPS-based for Jason-1, most notably describing phase center variations on-board antenna. also adopted new geopotential models Gravity Recovery and Climate Experiment...
The Jason-2 (OSTM) follow-on mission to Jason-1 provides for the continuation of global and regional mean sea level estimates along ground-track initial phase TOPEX/Poseidon mission. During first several months, flew in formation separated by only 55 seconds, enabling isolation inter-mission instrument biases through direct collinear differencing near simultaneous observations. Ku-band range bias with respect is estimated be −84 ± 9 mm, based on orbit altitudes provided Geophysical Data...
On December 7, 2001, the Jason-1 satellite was successfully launched by a Boeing Delta II rocket from Vandenberg site in California, USA. Its main mission to maintain high accuracy altimeter measurements, provided since 1992 TOPEX/Poseidon (T/P), ensuring continuity observing and monitoring ocean for intraseasonal interannual changes, mean sea level, tides, so forth. Despite four times less mass power, system has been designed have same performances as T/P, measuring surface topography at...
We use geodetic observations of the Earth to constrain anelasticity in Earth's mantle at periods between 12 hr and 18.6 yr. The include satellite laser ranging (SLR) measurements yr tides J2 component gravity field; space-based tidal variations rotation rate; optical Chandler Wobble period damping. These geophysical signals are mostly sensitive lower mantle. results suggest dissipative process could consist a single absorption band that extends across seismic out least as far ∼20 also...
We present a 17-year calibration record of precise (Jason-class) spaceborne altimetry from California offshore oil platform (Harvest). Our analyses indicate that the sea-surface-height (SSH) biases for all three TOPEX/Poseidon (1992–2005) measurement systems are statistically indistinguishable zero at 15 mm level. In contrast, SSH bias estimates newer Jason-1 mission (2001–present) and Ocean Surface Topography Mission (2008–present) significantly positive. orbit over eight years, system...
We assess the accuracy of JPL's estimated OSTM/Jason-2 Global Positioning System (GPS)-determined orbits based on residuals to independent satellite laser ranging (SLR) data, compared with produced by different software from data (SLR/DORIS), Geophysical Data Record version C (GDR-C) orbits, and altimeter crossover tests. All these tests are consistent sub-cm radial accuracy: high elevation SLR residual standard deviation lies at 6.8 mm, RMS differences GDR-C in component typically fall...
Abstract We describe a terrestrial reference frame (TRF) realization based on Global Positioning System (GPS) data alone. Our approach rests highly dynamic, long‐arc (9 day) estimation strategy and GPS satellite antenna calibrations derived from Gravity Recovery Climate Experiment TOPEX/Poseidon low Earth orbit receiver data. Based nearly 17 years of (1997–2013), our solution for scale rate agrees with International Terrestrial Reference Frame (ITRF)2008 to 0.03 ppb yr −1 , 3‐D origin...
Three empirical ocean tide models are determined from repeat cycles 10 to 78 of the TOPEX/POSEIDON (T/P) altimeter mission. The three investigate effects satellite orbit ephemeris on tides T/P altimetry and effect extracting free core nutation resonance in definition diurnal admittance. altimetric data series use Joint Gravity Model JGM‐2 geopotential preliminary JGM‐3 computed at University Texas, Center for Space Research. mission shown have precision necessary estimate monthly fortnightly...
Results are presented from the long-term monitoring and calibration of National Aeronautics Space Administration Jason Microwave Radiometer (JMR) on Jason-1 ocean altimetry satellite ground-based Advanced Water Vapor Radiometers (AWVRs) developed for Cassini Gravity Wave Experiment. Both radiometers retrieve wet tropospheric path delay (PD) atmosphere use internal noise diodes (NDs) gain calibration. The JMR is first radiometer to be flown in space that uses NDs External techniques used...
Abstract We evaluate models for the predicted diurnal and semidiurnal tidal variations in polar motion using observations based upon Global Positioning System (GPS). The GPS‐based are composed of 10 year continuous time series estimates with 15 min temporal resolution. Predicted effects account contributions from ocean tide angular momentum libration. consider two effects, both which have their heritage so‐called TPXO hydrodynamic heights currents that assimilate satellite altimetry,...
JPL has developed a terrestrial reference frame (TRF) based on combining space geodetic techniques at the observation level. The current version includes observations from Global Positioning System (GPS), Satellite Laser Ranging (SLR) and Very Long Baseline Interferometry (VLBI); it been shown to be competitive with international standard (ITRF2020) in terms of fundamental parameters (origin scale) their temporal evolution, both linear seasonal. In this work, we build processing...
Long‐period lunar fortnightly (Mf) and monthly (Mm) tides in the global oceans are of particular interest to geophysicists because their impact on Earth's rotation, they oceanographers from point view response characteristics low‐frequency forcing. have long been quite controversial, but precision altimetry is providing an accurate means measuring modeling them oceans. Here we describe Mf Mm extracted a 1° barotropic hydrodynamic tidal model, which assimilates ocean estimated cycles 10–130...
Abstract High-precision applications of GNSS require accurate calibrations to correct for phase variations the transmitting antennas. Calibrations distributed by International Service (IGS), based upon observations from global network ground stations, are often used as source transmitter they inherently linked a specific definition Terrestrial Reference Frame. The IGS provides antenna function boresight angle each basic block navigation satellite. To support scientific missions operating in...
The Harvest Oil Platform, near Point Conception, California, has long served as the NASA prime verification site for TOPEX/POSEIDON and Jason series of reference altimeter missions. In this brief review article, we provide a short history platform experiment dating to selection in 1989. We describe evolution data record over past three decades, demonstrate how results have informed development stable accurate climate sea level change from satellite altimetry.
In this second part, we explore the implications of tides derived from high‐resolution, data‐assimilative, nonlinear barotropic global ocean tidal model described by Kantha (this issue) in altimetric analysis and geophysical applications. It is shown that when applied to task removing sea surface height TOPEX records, performance comparable other models open as measured reduction crossover variances. The slightly better than only high‐resolution Grenoble (Le Provost et al., 1994). results...
NAVIGATION is a quarterly journal published by the Institute of Navigation. The publishes original, peer-reviewed articles on all aspects positioning, navigation, and timing. also selected technical notes survey articles, as well papers exceptional quality drawn from Institute’s conference proceedings.
Abstract A method is described to calibrate a satellite microwave radiometer operating near 18–37 GHz on decadal time scales for the purposes of climate studies. The uses stable on-earth brightness temperature references over full dynamic range temperatures stabilize calibration and applied Ocean Topography Experiment (TOPEX) Microwave Radiometer (TMR). These are vicarious cold reference, which statistical lower bound ocean surface temperature, heavily vegetated, pseudoblackbody regions in...