JB2008

The Jacchia-Bowman 2008 Empirical Thermospheric Density Model

JB2008 is based on Jacchia’s diffusion equations. Driving solar indices are computed from space-based sensor data, which provide the solar irradiances in the extreme through far ultraviolet, including x-ray and Lyman-α wavelengths. Exospheric temperature equations represent the thermospheric EUV and FUV heating. Semiannual density equations based on multiple 81-day average solar indices represent the variations in the semiannual density cycle that result from EUV heating. Geomagnetic storm effects are modeled using the Dst index as the driver of global density changes. Extensive model validation was performed by Bowman et al. [2008], which includes comparisons with accurate daily density drag data previously computed for numerous satellites in the altitude range of 175 to 1000 km, model comparisons between JB2008, JB2006, Jacchia 1970, and NRLMSIS-00 models, and comparisons to accelerometer measurements from the CHAMP and GRACE satellites.

Indices and Code Access

The JB2008 empirical thermospheric density model code is provided, as well as historical space weather indices with a 45-day lag.

Access JB2008 model code and historical indices arrow

SET offers current epoch and forecast operational indices to the community through the Unified Data Library (UDL). Whether for research or operational use, please visit the Unified Data Library site to request a subscription.

Figures

Figure 1. HASDM-to-Model density ratios at 400km altitude as a function of F10B.
Figure 1. HASDM-to-Model density ratios at 400km altitude as a function of F10B

Figure 2. Density percentage errors (1 standard deviation) from model density values at 400 km altitude compared to HASDM density values.
Figure 2. Density percentage errors (1 standard deviation) from model density values at 400 km altitude compared to HASDM density values.

Figure 3. The amplitude function F(z) for three different years (1990, 1993, 2002), with semiannual amplitudes plotted for each satellite for each year. The constant F(z) function from Jacchia is also plotted.
Figure 3. The amplitude function F(z) for three different years (1990, 1993, 2002), with semiannual amplitudes plotted for each satellite for each year. The constant F(z) function from Jacchia is also plotted.

Figure 4. A multiple storm during 2004, showing the different storm events.
Figure 4. A multiple storm during 2004, showing the different storm events.

Figure 5. Major 2004 storms with Dst, ap (left scale) , and density (Rho) ratios displayed. The density ratios are based on orbit averaged model density values / GRACE 2004 density average.
Figure 5. Major 2004 storms with Dst, ap (left scale) , and density (Rho) ratios displayed. The density ratios are based on orbit averaged model density values / GRACE 2004 density average.

Figure 6. Major 2003 storms with Dst, ap (left scale), and density (Rho) ratios displayed. The density ratios are based on orbit averaged model density values / CHAMP 2003 density average.
Figure 6. Major 2003 storms with Dst, ap (left scale), and density (Rho) ratios displayed. The density ratios are based on orbit averaged model density values / CHAMP 2003 density average.

Figure 7. Model density 1-standard deviation errors as a function of ap ranges representing storm magnitudes. Values are based on orbit averaged percent density differences between the calibrated accelerometer data, from both CHAMP and GRACE, and the different model values. JB2006 uses the same geomagnetic storm modeling as J70.
Figure 7. Model density 1-standard deviation errors as a function of ap ranges representing storm magnitudes. Values are based on orbit averaged percent density differences between the calibrated accelerometer data, from both CHAMP and GRACE, and the different model values. JB2006 uses the same geomagnetic storm modeling as J70.

Publications, License, and Acknowledgement

Publications

  • A New Empirical Thermospheric Density Model
    JB2008 Using New Solar and Geomagnetic Indices
  • JB2008 model using new indices
  • Bowman et al.
  • AIAA_2008-6438_JB2008_Model.pdf
  • The development of new solar indices for use in thermospheric density modeling
  • JB2006 indices
  • Tobiska et. al.
  • JB2006_JASTP_2008_803.pdf
  • The JB2006 empirical thermospheric density model
  • JB2006 model
  • Bowman et. al.
  • JASTP_Bowman_JB2006_2008.pdf
  • Improvements in Modeling Thermospheric Densities Using New EUV and FUV Solar Indices
  • 2006_237_Density_Improvements
  • Bowman, Tobiska
  • JB2006_AAS_2006_237.pdf
  • Advances in Solar Inputs for Precision Orbit Determination
  • 2005_252_Solar_Inputs
  • Tobiska
  • JB2006_AAS_2005_252.pdf
  • Drag Coefficient Variability at 175-500 km from the Orbit Decay Analyses of Spheres
  • 2005_257_Drag_Coef_Variability
  • Bowman, Moe
  • JB2006_AAS_2005_257.pdf
  • A Method For Computing Accurate Daily Atmospheric Density Values From Satellite Drag Data
  • 2004_173_AAS_EDR_Method
  • Bowman et. al.
  • JB2006_AAS_2004_173.pdf
  • High Accuracy Satellite Drag Model (HASDM) Review
  • 2003_625_HASDM_Review
  • Bowman, Strorz
  • JB2006_AAS_2003_625.pdf
  • High Accuracy Satellite Drag Model (HASDM)
  • 2002_4886_HASDM
  • Storz et. al.
  • JB2006_AIAA_2002_4886.pdf
  • True Satellite Ballistic Coefficient Determination for HASDM
  • 2002_4887_True_B
  • Bowman
  • JB2006_AIAA_2002_4887.pdf
  • Atmospheric Density Variations at 1500-4000 km Height Determined from Long Term Orbit Perturbation Analysis
  • 2001_132 Den_Var _1500-4000km
  • Bowman
  • JB2006_AAS_2001_132.pdf
  • Orbit Perturbation Analysis of West Ford Needles Clusters
  • 2000_4236_Needles_Perts
  • Bowman
  • JB2006_AIAA_2000_4236.pdf

SOFTWARE LICENSE AND WARRANTY AGREEMENT Software License and Warranty Agreement,
JB2006 and JB2008 Empirical Thermospheric Density Models

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Acknowledgement

When using JB2008 indices or other data from this website in a publication or conference paper, please acknowledge use of the data as: “The JB2008 solar and geomagnetic indices are provided for scientific use courtesy of Space Environment Technologies.”