Quantum technology for future earth observation from space - gradiometry case

Kurzfassung

In various geoscience disciplines, there is a huge interest in knowing the mass variations of the Earth with high resolution and accuracy. It is vital for monitoring climate change processes to define corresponding requirements for the sensor technology and for possible satellite missions. The future satellite missions will strongly depend on the advancement of novel technology and beneficial observation concepts of the Earth gravitational field. In this study, various quantum and hybrid gradiometer concepts are first characterized and corresponding error properties are described. Here, special attention is paid to Cold Atom Interferometry (CAI) accelerometers and gradiometers that will perfectly supplement the classical electrostatic concepts due to their white noise behavior at low frequencies. Those, accelerometers and gradiometers using atom interferometry have great potential for increasing the accuracy of future gravity satellite missions. We will compare hybrid with classical electrostatic gradiometers (as also used in GOCE) and illustrate their different spectral behavior as well as their mutual benefit. Using simulated atom-interferometric and hybrid gradient measurements along one or more gradiometer axes in GOCE-like orbits, we determine the gravity field in spherical harmonics coefficients for the various cases and discuss the pros and cons of the selected concepts.