1. MTR, swarm E2E study, Nov 11, 2003, DSRI Copenhagen, nio #1 7-Sep-15 swarm End-To-End Mission Performance Study Mid Term Review The swarm E2E Consortium DSRI: Eigil Friis Christensen Flemming Hansen Nils Olsen Per Lundahl Thomsen Susanne Vennerstrøm IPGP: Gauthier Hulot Mioara Mandea BGS: Vincent Lesur Susan Macmillan Alan Thomson GFZ: Monika Korte Hermann Lühr Stefan Maus Christoph Reigber Patricia Ritter Martin Rother GSFC: Michael Purucker Terence Sabaka IUEM: Pascal Tarits

2. MTR, swarm E2E study, Nov 11, 2003, DSRI Copenhagen, nio #2 7-Sep-15 swarm Mid Term Review Draft Agenda Achieved Milestones Presentation of the results achieved in Task 2 –Example 1: Lithospheric Field Recovery (HL) –Example 2: Comprehensive Inversion (TJS) How to proceed in Task 3 General discussion

3. MTR, swarm E2E study, Nov 11, 2003, DSRI Copenhagen, nio #3 7-Sep-15 Achieved Milestones Task 1: Development, implementation, test and delivery of documented software modules to industry –calculation of the magnetic field and its variations for a given position and time Design of a reference model (swarm_02a_03) up to Spherical Harmonic Degree n=120 Task 2: Design, implementation and test of modules to produce synthetic data –orbit generator –magnetic field generator –electric field generator –auxiliary data

4. MTR, swarm E2E study, Nov 11, 2003, DSRI Copenhagen, nio #4 7-Sep-15 Achieved Milestones (cont.) Task 2: Development of Testplan –test quantities and procedure Successful closed-loop simulation recovery of field using data that only contain contributions from those fields –Example 1: lithospheric field (cf. presentation by Hermann Lühr) –Example 2: comprehensive inversion (cf. presentation by Terence J. Sabaka) Successful ”full inversion” noise-free data, but containing all source contributions (and thus unmodeled external signals) –Recovery of lithospheric field at least up to n=85 (cf. HL+TJS) –Recovery of high-degree secular variation at least up to n=19 (cf. TJS)

5. MTR, swarm E2E study, Nov 11, 2003, DSRI Copenhagen, nio #5 7-Sep-15 Outline of Task 2 (red boxes are part of Task 3)

6. MTR, swarm E2E study, Nov 11, 2003, DSRI Copenhagen, nio #6 7-Sep-15 Orbit Design Initial Constellation # 1 Two pairs of satellites 450 and 550 km initial altitude 86.0° and 85.4° inclination lower satellites are close together separation a few hundred km upper satellites are at antipodal position 180° separation Different inclinations yields different drift rates 0.44 min/day differential drift rate corresponding to 90° separation after 27 months

7. MTR, swarm E2E study, Nov 11, 2003, DSRI Copenhagen, nio #7 7-Sep-15 Magnetic Field Generation From the Comprehensive Model CM4 (Sabaka et al) High-degree crustal field (n up to 120) and secular variation (n up to 20) from synthetic model

8. MTR, swarm E2E study, Nov 11, 2003, DSRI Copenhagen, nio #8 7-Sep-15 Data Products: Overview

9. MTR, swarm E2E study, Nov 11, 2003, DSRI Copenhagen, nio #9 7-Sep-15 Test Plan Closed-loop-simulation: Test of the forward and inversion approaches using noise-free data –using data that only contain source fields for which we invert for Focus on field contributions that are main swarm objectives –Core field and secular variation –Lithospheric field Test quantities: Difference between recovered and original model –Power spectrum of the model SH coefficients –Degree correlation  n of coefficients –Sensitivity matrix –Global Maps (e.g., of B r ) of the model difference Results: –successful recovery of the original model using clean and noise-free data Definition: noise-free datadata without additional S/C and payload noise clean datadata that only contain source contributions that is inverted for

10. MTR, swarm E2E study, Nov 11, 2003, DSRI Copenhagen, nio #10 7-Sep-15 Various Approaches for Field Recovery Comprehensive Inversion Core Surface Field and Secular Variation - Method 1 Earth Surface Main Field and Secular Variation Lithospheric Field Recovery - Method 1 Lithospheric Field Recovery - Method 2

11. MTR, swarm E2E study, Nov 11, 2003, DSRI Copenhagen, nio #11 7-Sep-15 Example of Study Result Recovery of lithospheric field...... and of high-degree secular variation using data from 4 swarm satellites and 88 observatories degree correlation  n > 0.9 Achieved by Comprehensive Inversion; details will be given by T.J. Sabaka original model recovered model difference

12. MTR, swarm E2E study, Nov 11, 2003, DSRI Copenhagen, nio #12 7-Sep-15 How to proceed in Task 3 Adjustment of Forward Scheme –perform experiments with small-scale contributions from ionospheric and toroidal fields –perform experiments with large-scale magnetospheric field (e.g. non-periodic variations of coefficients with n>1) –induced field due to 3D conductivity (oceans, sediments and mantle) Inclusion of S/C and Payload Noise Other Constellation/Combination of Satellites –additional ”constellation #1” satellites »inversion using data from up to 4 out of, e.g., 6 satellites –new constellation: #2