Academia.eduAcademia.edu

Figure 6 – uploaded by Ian McWhirter

See full PDFdownloadDownload figure
Figure 6. Panels (a) and (b) show the solar maximum (2001-2003) FPI winter average wind components at Longyearbyen for geomagneti- cally quiet conditions (0 < Kp<27). Zonal (a) and meridional (b) average winds and the standard errors of the mean are plotted. North and east are shown using purple lines in (b) and (a) respectively, whereas south and west are shown using light blue lines in (b) and (a) respec- tively. Panels (c) and (d) show the solar minimum (2005-2007) FPI winter average wind components at Longyearbyen for geomagnetically quiet conditions (0 < Kp<27 ). Zonal (c) and meridional (d) average winds and the standard errors of the mean are plotted. North and east are shown using purple lines in (d) and (b) respectively, whereas south and west are shown using light blue lines (d) and (b) respectively.

Figure 6 Panels (a) and (b) show the solar maximum (2001-2003) FPI winter average wind components at Longyearbyen for geomagneti- cally quiet conditions (0 < Kp<27). Zonal (a) and meridional (b) average winds and the standard errors of the mean are plotted. North and east are shown using purple lines in (b) and (a) respectively, whereas south and west are shown using light blue lines in (b) and (a) respec- tively. Panels (c) and (d) show the solar minimum (2005-2007) FPI winter average wind components at Longyearbyen for geomagnetically quiet conditions (0 < Kp<27 ). Zonal (c) and meridional (d) average winds and the standard errors of the mean are plotted. North and east are shown using purple lines in (d) and (b) respectively, whereas south and west are shown using light blue lines (d) and (b) respectively.

Related Figures (16)

Table 1. Geographic and geomagnetic AACGM coordinates of the FPI facility related to the KEOPS site in Kiruna (see text) Table 2. The same as in Table 1, but for the FPI site in Longyearbyen. The observatory’s historic names are given in parentheses.
Table 1. Geographic and geomagnetic AACGM coordinates of the FPI facility related to the KEOPS site in Kiruna (see text) Table 2. The same as in Table 1, but for the FPI site in Longyearbyen. The observatory’s historic names are given in parentheses.
5.1 CHAMP average winds
5.1 CHAMP average winds
Figure 1. CHAMP observations over Longyearbyen during solar maximum 2001-2003. Panel (a) shows the average values for all data — ascending (blue) and descending (red), panel (b) shows summer (May—August) averages and panel (c) shows winter (end October—early March) averages.
Figure 1. CHAMP observations over Longyearbyen during solar maximum 2001-2003. Panel (a) shows the average values for all data — ascending (blue) and descending (red), panel (b) shows summer (May—August) averages and panel (c) shows winter (end October—early March) averages.
Figure 2. CHAMP observations over KEOPS during solar maximum 2001-2003. Panel (a) shows the average values for all data — ascend- ing (blue) and descending (red), panel (b) shows summer (May—August) averages and panel (c) shows winter (end October—early March) averages.
Figure 2. CHAMP observations over KEOPS during solar maximum 2001-2003. Panel (a) shows the average values for all data — ascend- ing (blue) and descending (red), panel (b) shows summer (May—August) averages and panel (c) shows winter (end October—early March) averages.
Figure 3. Geometry illustrating the projection of the FPI viewing direction horizontal wind components onto the CHAMP cross-track orientation for the ascending and descending tracks.
Figure 3. Geometry illustrating the projection of the FPI viewing direction horizontal wind components onto the CHAMP cross-track orientation for the ascending and descending tracks.
Figure 4. CHAMP observations over Longyearbyen during solar minimum 2005-2007. Panel (a) shows the average values for all data — ascending (blue) and descending (red), panel (b) shows summer (May—August) averages and panel (c) shows winter (end October—early March) averages.
Figure 4. CHAMP observations over Longyearbyen during solar minimum 2005-2007. Panel (a) shows the average values for all data — ascending (blue) and descending (red), panel (b) shows summer (May—August) averages and panel (c) shows winter (end October—early March) averages.
Figure 5. CHAMP observations over KEOPS during solar minimum 2005-2007. Panel (a) shows the average values for all data — ascend- ing (blue) and descending (red), panel (b) shows summer (May—August) averages and panel (c) shows winter (end October-early March) averages.
Figure 5. CHAMP observations over KEOPS during solar minimum 2005-2007. Panel (a) shows the average values for all data — ascend- ing (blue) and descending (red), panel (b) shows summer (May—August) averages and panel (c) shows winter (end October-early March) averages.
Figure 7. Panels (a) and (b) show the solar maximum (2001-2003) FPI winter average wind components at KEOPS for geomagnetically quiet conditions (0 < Kp<2°). Zonal (a) and meridional (b) average winds and the standard errors of the mean are plotted. North and east are shown using purple lines in (b) and (a) respectively, whereas south and west are shown using light blue lines in (b) and (a) respectively. Panels (c) and (d) show the solar minimum (2005-2007) FPI winter average wind components at KEOPS for geomagnetically quiet conditions (0 <Kp<2_7 ). Zonal (a) and meridional (b) average winds and the standard errors of the mean are plotted. North and east are shown using purple lines in (d) and (b) respectively, whereas south and west are shown using light blue lines (d) and (b) respectively.
Figure 7. Panels (a) and (b) show the solar maximum (2001-2003) FPI winter average wind components at KEOPS for geomagnetically quiet conditions (0 < Kp<2°). Zonal (a) and meridional (b) average winds and the standard errors of the mean are plotted. North and east are shown using purple lines in (b) and (a) respectively, whereas south and west are shown using light blue lines in (b) and (a) respectively. Panels (c) and (d) show the solar minimum (2005-2007) FPI winter average wind components at KEOPS for geomagnetically quiet conditions (0 <Kp<2_7 ). Zonal (a) and meridional (b) average winds and the standard errors of the mean are plotted. North and east are shown using purple lines in (d) and (b) respectively, whereas south and west are shown using light blue lines (d) and (b) respectively.
Figure 8. Longyearbyen (Svalbard) winters 2001-2003, 2~ <Kp<4™: average zonal winds measured using CHAMP and FPI, including standard errors of the mean. These are compared with FPI winds observed by the University of Alaska in 1980 and the HWM93 model winds. A. Aruliah et al.: Comparing high-latitude thermospheric winds
Figure 8. Longyearbyen (Svalbard) winters 2001-2003, 2~ <Kp<4™: average zonal winds measured using CHAMP and FPI, including standard errors of the mean. These are compared with FPI winds observed by the University of Alaska in 1980 and the HWM93 model winds. A. Aruliah et al.: Comparing high-latitude thermospheric winds
Figure 9. Comparison of CHAMP and FPI measurements of KEOPS zonal average winds to the FPI east and west volumes, including standard errors of the mean, for the winters of 2001-2003. These are compared to the HWM93 model winds.
Figure 9. Comparison of CHAMP and FPI measurements of KEOPS zonal average winds to the FPI east and west volumes, including standard errors of the mean, for the winters of 2001-2003. These are compared to the HWM93 model winds.
Figure 10. Frequency distribution of the ratios of CHAMP/FPI 1h averaged zonal wind magnitudes observed in the winter period fc solar max under moderately active conditions (2~ <Kp<4+) for Longyearbyen (blue) and KEOPS (red). Panel (a) shows the frequenc distribution of the CHAMP/FPI ratios. Panel (b) shows the UT dependence of the ratios.
Figure 10. Frequency distribution of the ratios of CHAMP/FPI 1h averaged zonal wind magnitudes observed in the winter period fc solar max under moderately active conditions (2~ <Kp<4+) for Longyearbyen (blue) and KEOPS (red). Panel (a) shows the frequenc distribution of the CHAMP/FPI ratios. Panel (b) shows the UT dependence of the ratios.
Figure 11. CMAT2 zonally averaged zonal winds for 00:00 UT at the December solstice 2008 (solar minimum conditions) to demonstrate the effect of drastically reducing the molecular viscosity in order to raise the altitude where winds become independent of altitude. Panel (a) shows isobars for a standard simulation, whereas panel (b) represents a simulation where the molecular viscosity is 100 times smaller (from Hood, 2018). A. Aruliah et al.: Comparing high-latitude thermospheric winds
Figure 11. CMAT2 zonally averaged zonal winds for 00:00 UT at the December solstice 2008 (solar minimum conditions) to demonstrate the effect of drastically reducing the molecular viscosity in order to raise the altitude where winds become independent of altitude. Panel (a) shows isobars for a standard simulation, whereas panel (b) represents a simulation where the molecular viscosity is 100 times smaller (from Hood, 2018). A. Aruliah et al.: Comparing high-latitude thermospheric winds
Figure 12. (a) Height profile of CMAT2 zonal winds at Svalbard. (b) Height profile of the red line emission intensity profile from the Vlasov et al. (2005) model. A. Aruliah et al.: Comparing high-latitude thermospheric winds
Figure 12. (a) Height profile of CMAT2 zonal winds at Svalbard. (b) Height profile of the red line emission intensity profile from the Vlasov et al. (2005) model. A. Aruliah et al.: Comparing high-latitude thermospheric winds
Figure 13. Frequency distribution of Kp values. (a) From 2001 to 2003 representing solar maximum. (b) From 2000 to 2009 covering most of the period of the CHAMP lifetime. A. Aruliah et al.: Comparing high-latitude thermospheric winds
Figure 13. Frequency distribution of Kp values. (a) From 2001 to 2003 representing solar maximum. (b) From 2000 to 2009 covering most of the period of the CHAMP lifetime. A. Aruliah et al.: Comparing high-latitude thermospheric winds
Figure 14. (a, b) CMAT2 zonally averaged zonal winds for a quiet day on 1 December 2007 at Longyearbyen (a, c) and Kiruna (b, d) for winds at 180, 200 and 240 km for comparison with the height-integrated winds weighted using an emission intensity profile from the Vlasov et al. (2005) model. (c, d) The same for active conditions on 20 March 2015.
Figure 14. (a, b) CMAT2 zonally averaged zonal winds for a quiet day on 1 December 2007 at Longyearbyen (a, c) and Kiruna (b, d) for winds at 180, 200 and 240 km for comparison with the height-integrated winds weighted using an emission intensity profile from the Vlasov et al. (2005) model. (c, d) The same for active conditions on 20 March 2015.
Figure 15. CMAT2 global zonal winds for a quiet day on 1 December 2007 for the winds at 240 km and the height-integrated winds weighted using an emission profile from Vlasov et al. (2005) model. The top row shows 00:00 UT (the two left panels) and 06:00 UT (the two right panels); the bottom shows 12:00 UT (the two left panels) and 18:00 UT (the two right panels).
Figure 15. CMAT2 global zonal winds for a quiet day on 1 December 2007 for the winds at 240 km and the height-integrated winds weighted using an emission profile from Vlasov et al. (2005) model. The top row shows 00:00 UT (the two left panels) and 06:00 UT (the two right panels); the bottom shows 12:00 UT (the two left panels) and 18:00 UT (the two right panels).
Related topics:
GeophysicsAtmospheric sciences
580 California St., Suite 400
San Francisco, CA, 94104
© 2025 Academia. All rights reserved