According to ESA SP-1279(6) "Swarm - The Earth Magnetic Field and Environment Explorer, Report for Mission Selection" (April 2004), the five research objectives of the Swarm mission are:
During the ESA Swarm study "Preparation of the Swarm Level 2 Data Processing" advanced models for the various contributions to the Earth's magnetic field have been identified as Level 2 products. In particular, the Comprehensive Inversion (CI) providing mathematical descriptions of the various geomagnetic field contributions is required. In order to derive the best model for each of the various contributions to the geomagnetic field, it is necessary to co-estimate or correct for various other parts to the field. As an example, fields from magnetospheric and ionospheric currents and their Earth-induced counterparts have to be considered when modelling the internal part of the field. If a typical user of magnetic field models relies only on standard models, he/she may not be able to take full advantage of the constellation measurements and thus miss the advantages offered by Swarm. This clearly argues for advanced Swarm Level 2 magnetic field models.
Also the other science objectives, for instance determination of the electrical conductivity of the mantle, require data products with a good description of the time-space structure of the external (magnetospheric) field and its Earth-induced counterpart.
How the products are attributed to the Swarm Science Objectives is described in Table 1 and 2 in Level 2 Product Definitions.