DOI: 10.5281/zenodo.11559809
title: Different behavior of density perturbations between dayside and nightside in the Martian thermosphere and the ionosphere associated with atmospheric gravity waves

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GENERAL INFORMATION

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1. Title of Dataset: Different behavior of density perturbations between dayside and nightside in the Martian thermosphere and the ionosphere associated with atmospheric gravity waves

 

2. Authors: Nakagawa, England, et al.

 

3. Contact information: hiromu.nakagawa.c1@tohoku.ac.jp

 

4. Date of data collection: April 2024

 

 

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DATA & FILE OVERVIEW

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1. Original MAVEN data access:

 

The MAVEN/NGIMS (level-2, version-8, revision-1) are publicly available in ASCII format on the NASA Planetary Data System (PDS) at https://atmos.nmsu.edu/data_and_services/atmospheres_data/MAVEN/ngims.html.

 

As for references in Figures 2-4, the MAVEN/MAG Calibrated data are publicly available in ASCII format on the NASA Planetary Data System (PDS) at https://pds-ppi.igpp.ucla.edu/search/view/?id=pds://PPI/maven.mag.calibrated.

 

 

2. File List:

 

[1] correlate_coefficients.txt

[2] rmse_170-190_coupling_case.txt

[3] rmse_190-210_coupling_case.txt

[4] rmse_170-190_ion_specific_case.txt

[5] rmse_190_210_ion_specific_case.txt

 

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DATA-SPECIFIC INFORMATION

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[1] correlate_coefficients.txt

This includes the geometric information and the calculated correlate coefficient between neutrals and ions in all profiles applied in this study. The first header provides the information in the file: Orbit, Year, Month, Day, Hour, Minute, Unix time, SZA(deg), Lon(deg), Lat(deg), LST(hr), CC(CO2-N2), CC(CO2-CO2+). The geometric information corresponds to those at altitude around 190 km. The last two columns represents the correlate coefficients between CO2 and N2 and between CO2 and CO2+. 

 

[2] rmse_170-190_coupling_case.txt

This includes RMSE (the unit is percentage) between the observed perturbations and the model fit. The first header provides the information in the file: unix_time, orbit number, sza, lon, lat, lst, rmse_neu_gw_%, rmse_neu_aw_%, rmse_ion_gw_%, rmse_ion_aw_%. The geometric information corresponds to those at altitude around 190 km. The last four RMSEs represents those with the model to fit with the gravity waves (gw) parameters and with the acoustic waves (aw) for the neutral (neu) perturbations (N2) and for the ion (ion) perturbations (CO2+) at altitude range between 170 km and 190 km for the case of ion-neutral coupling case. 

 

[3] rmse_190-210_coupling_case.txt

This includes RMSE (the unit is percentage) between the observed perturbations and the model fit. The first header provides the information in the file: unix_time, orbit number, sza, lon, lat, lst, rmse_neu_gw_%, rmse_neu_aw_%, rmse_ion_gw_%, rmse_ion_aw_%. The geometric information corresponds to those at altitude around 190 km. The last four RMSEs represents those with the model to fit with the gravity waves (gw) parameters and with the acoustic waves (aw) for the neutral (neu) perturbations (N2) and for the ion (ion) perturbations (CO2+) at altitude range between 190 km and 210 km for the case of ion-neutral coupling case. 

 

[4] rmse_170-190_ion_specific_case.txt

This includes RMSE (the unit is percentage) between the observed perturbations and the model fit. The first header provides the information in the file: unix_time, orbit number, sza, lon, lat, lst, rmse_neu_gw_%, rmse_neu_aw_%, rmse_ion_gw_%, rmse_ion_aw_%. The geometric information corresponds to those at altitude around 190 km. The last four RMSEs represents those with the model to fit with the gravity waves (gw) parameters and with the acoustic waves (aw) for the neutral (neu) perturbations (N2) and for the ion (ion) perturbations (CO2+) at altitude range between 170 km and 190 km for the case of ion-specific case. 

 

[5] rmse_190_210_ion_specific_case.txt

This includes RMSE (the unit is percentage) between the observed perturbations and the model fit. The first header provides the information in the file: unix_time, orbit number, sza, lon, lat, lst, rmse_neu_gw_%, rmse_neu_aw_%, rmse_ion_gw_%, rmse_ion_aw_%. The geometric information corresponds to those at altitude around 190 km. The last four RMSEs represents those with the model to fit with the gravity waves (gw) parameters and with the acoustic waves (aw) for the neutral (neu) perturbations (N2) and for the ion (ion) perturbations (CO2+) at altitude range between 190 km and 210 km for the case of ion-specific case. 

 

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METHODOLOGICAL INFORMATION

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Period to analysis: from March 2015 to August 2020 (orbit number from 713 to 11881)

 

Number of files (CO2): 8,911

 

Number of files (N2): 8,913

 

Number of files (CO2+): 7,053(?)

 

Data selection:

 

1. Neutral species with inbound valid (IV)

 

2. Ion species with SCP (quality flag=0)

 

3. Simultaneous observations of CO2, N2, and CO2+ at altitudes 170-210 km

 

4. All three species CO2, N2, and CO2+ are valid with data sample >10 points in a single orbit.

 

Total number of files after data selection = 3,018

 

Fitting:

 

4th-order polynomial fit to extract the perturbation components of density in the range between 160 and 220 km.

 

 

Correlation coefficient:

 

The correlation coefficients between perturbations are calculated in the range between 170 and 210 km.

 

Ion-neutral coupling cases whose correlation coefficient between CO2 and CO2+ larger than 0.7: Total number = 839

 

Ion-specific case whose correlation coefficient between CO2 and CO2+ smaller than 0.2:  Total number = 823

 

#We also define CME cases based on Lee et al. (2017):  Total number = 31 cases