Orbit-averaged relative thermospheric neutral mass density changes at 450 km altitude from Swarm, GRACE and GRACE-FO

Relative density changes at 450 km altitude for Swarm, GRACE and GRACE-FO satellites Orbit-averaged thermospheric neutral mass density changes (in percentage) relative to a quiet-time baseline derived from the three quietest days per month, altitude-adjusted to 450 km reference altitude. This dataset was calculated as described in the JGR: Space Physics article "Changes in Global Thermospheric Mass Density During ICME and HSS-Driven Geomagnetic Storms" covering the period from 2010 to 2025. The data files contain the variables detailed in the table below. More information can be found in the article and the supporting information. Variable name Dimensions Units Content Time (Nₜᵢₘₑ, 1) ms Timestamp given in CDF epoch time drho_A (Nₜᵢₘₑ, 1) % Swarm-A Relative Change of Orbit-Averaged Neutral Density @450 km. rho_A (Nₜᵢₘₑ, 1) kg/m³ Swarm-A Orbit-Averaged Neutral Mass Density @450 km. alt_A (Nₜᵢₘₑ, 1) m Swarm-A Orbit Averaged Satellite Altitude Quiet_rho_A (Nₜᵢₘₑ, 1) kg/m³ Swarm-A Quiet Time Background Neutral Density drho_B (Nₜᵢₘₑ, 1) % Swarm-B Relative Change of Orbit-Averaged Neutral Density @450 km. rho_B (Nₜᵢₘₑ, 1) kg/m³ Swarm-B Orbit-Averaged Neutral Mass Density @450 km. alt_B (Nₜᵢₘₑ, 1) m Swarm-B Orbit Averaged Satellite Altitude Quiet_rho_B (Nₜᵢₘₑ, 1) kg/m³ Swarm-B Quiet Time Background Neutral Density drho_C (Nₜᵢₘₑ, 1) % Swarm-C Relative Change of Orbit-Averaged Neutral Density @450 km. rho_C (Nₜᵢₘₑ, 1) kg/m³ Swarm-C Orbit-Averaged Neutral Mass Density @450 km. alt_C (Nₜᵢₘₑ, 1) m Swarm-C Orbit Averaged Satellite Altitude Quiet_rho_C (Nₜᵢₘₑ, 1) kg/m³ Swarm-C Quiet Time Background Neutral Density drho_GA (Nₜᵢₘₑ, 1) % GRACE-A Relative Change of Orbit-Averaged Neutral Density @450 km. rho_GA (Nₜᵢₘₑ, 1) kg/m³ GRACE-A Orbit-Averaged Neutral Mass Density @450 km. alt_GA (Nₜᵢₘₑ, 1) m GRACE-A Orbit Averaged Satellite Altitude Quiet_rho_GA (Nₜᵢₘₑ, 1) kg/m³ GRACE-A Quiet Time Background Neutral Density drho_GB (Nₜᵢₘₑ, 1) % GRACE-B Relative Change of Orbit-Averaged Neutral Density @450 km. rho_GB (Nₜᵢₘₑ, 1) kg/m³ GRACE-B Orbit-Averaged Neutral Mass Density @450 km. alt_GB (Nₜᵢₘₑ, 1) m GRACE-B Orbit Averaged Satellite Altitude Quiet_rho_GB (Nₜᵢₘₑ, 1) kg/m³ GRACE-B Quiet Time Background Neutral Density drho_FO (Nₜᵢₘₑ, 1) % GRACE-FO Relative Change of Orbit-Averaged Neutral Density @450 km. rho_FO (Nₜᵢₘₑ, 1) kg/m³ GRACE-FO Orbit-Averaged Neutral Mass Density @450 km. alt_FO (Nₜᵢₘₑ, 1) m GRACE-FO Orbit Averaged Satellite Altitude Quiet_rho_FO (Nₜᵢₘₑ, 1) kg/m³ GRACE-FO Quiet Time Background Neutral Density Time step 30 seconds Filler values NaN File size 640 KB for each daily file File format CDF Metadata Date created and input filenames of the original satellite data used in the derivation of $\delta\rho_450km$. Saved for version control. The three previous and next quietest days used to calculate the quiet time density baseline for each satellite. File name JOIN_drho450km_[Time Start]_[Time End]_[Version].cdf For questions or data inquiries contact Marcus Pedersen ([e-mail])