Monthly gravity fields from Swarm A, B, and C, using the integral equation approach with short arcs.

Software: GROOPS;
Approach: Short-arc approach (Mayer-Gürr, 2006);
Kinematic orbit product: IfG Graz: https://ftp.tugraz.at/outgoing/ITSG/satelliteOrbitProducts/operational/Swarm-1/kinematicOrbit/;
Arc length: 45 minutes;
Reference GFM: GOCO06s (Kvas et. al, 2021), monthly mean has been added back to the solution;
Drag model: NRLMSIS2;
SRP and EARP and EIRP models: Vielberg & Kusche (2020);
Empirical parameters: + for non-gravitational accelerations (sum of Drag+SRP+EIRP+EARP): Bias per arc and direction; + for Drag: Scale per arc and direction; + for radiation pressure (sum of SRP+EIRP+EARP): Scale per day and direction;
Non-tidal model: Atmosphere and Ocean De-aliasing Level 1B RL06 (Dobslaw et al., 2017);
Ocean tidal model: 2014 finite element solution FES2014b (Carrere et al., 2015);
Atmospheric tidal model: AOD1B RL06 atmospheric tides ;
Solid Earth tidal model: IERS2010;
Pole tidal model: IERS2010;
Ocean pole tidal model: IERS2010 (Desai 2002);
Third-body perturbations: Sun, Moon, Mercury, Venus, Mars, Jupiter, and Saturn, following the JPL DE421 Planetary and Lunar Ephemerides (Folkner et al., 2014).