Date: October 2nd, 2021

Dataset Title: Swarm and IGRF-12, CHAOS-6 Magnetic Field Vector Residuals 

Dataset Creator: Yining Shi, Mark Moldwin

Dataset Contact: Yining Shi yining@umich.edu

Funding: NASA Grants 80NSSC19K0608 and 80NSSC20K1779

Key Points:
- Comparison between Swarm magnetic field vector observations and Earth magnetic field models IGRF-12 and CHAOS-6 for different Kp levels.

Methodology:
The data are Swarm L1b magnetic field vectors from Nov. 25th, 2013 to Dec. 31th, 2020. obtained from Swarm Virtual Research Environment (VRE) https://viresclient.readthedocs.io/en/latest/
IGRF-12 and CHOAS-6 modeled Earth magnetic field vectors are estimated at Swarm satellite locations also obatined from Swarm VRE. 
Magnetic field residuals are calculated as difference between Swarm observation and modeled magnetic field vectors. Magnitude of magnetic field residual and angle between Swarm observations and modeled magnetic field vectos are also calculated.
Data are categorized based on Kp*10 index included in available Swarm VRE indices.

Instrument and/software specifications: Swarm VRE JupyterLab 

Files contained here are:
Kp10_30_35.csv
Kp10_35_40.csv
Kp10_40_45.csv
Kp10_45_50.csv
Kp10_50_55.csv
Kp10_55_60.csv
Kp10_60_70.csv
Kp10_70_80.csv
Kp10_80_90.csv

Each csv file contains:
Timestamp, Data flag, Spacecraft number, Latitude, Longitude, Radius in geocentric coordinate of the Swarm satellites; and corresponding Magnetic latitude, magnetic longitude and mangetic local time of the Swarm satellites in AACGM coordinate above 40/-40 degree latitude and CGM coordinate below.
Swarm magnetic field vector in North-East-Center (NEC) coordinate and its error 'B_NEC' and 'B_error'; mangitude of error 'B_error_mag' IGRF magnetic field vector 'B_NEC_IGRF'; CHAOS magnetic field vector ' B_NEC_CHAOS'; Swarm-IGRF and Swarm-CHAOS residual vector 'B_NEC_res_IGRF' and 'B_NEC_res_CHAOS' and their magnitude 'B_NEC_res_IGRF_mag' and 'B_NEC_res_CHAOS_mag';
Swarm data derived Earth core, lithospheric, magnetospheric and ionospheric magnetic field 'SwarmCI' was tried but not included in the study due to missing data points compared to IGRF and CHOAS so 'B_NEC_SwarmCI' is blank. 
All magnetic field vectors are in nT.
Swarm, IGRF and CHAOS magnetic filed unit vector 'B_NEC_unit', 'B_IGRF_unit' and 'B_CHAOS_unit'; Swarm-IGRF and Swarm-CHAOS angle difference 'angle_IGRF' and 'angle_CHAOS' in degrees;
Kp*10 and Dst index at Timestamp;
Solar wind By and Bz in GSM coordinate 'IMF_BY_GSM' and 'IMF_BZ_GSM' in nT and solar wind speed 'IMF_V' in km/s.

Use and Access:
This data set is made available under a Attribution-NonCommercial 4.0 International license.