Radio science measurements of atmospheric refractivity with Mars Global Surveyor

Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

10

Planetary Sciences: Solid Surface Planets: Meteorology (3346), Planetary Sciences: Solid Surface Planets: Ionospheres (2459), Planetary Sciences: Solar System Objects: Mars

Scientific paper

Radio occultation experiments with Mars Global Surveyor measure the refractive index of the Martian atmosphere from the surface to ~250 km in geopotential height. Refractivity is proportional to neutral density at low altitudes and electron density at high altitudes, with a transition at ~75 km. We use weighted least squares to decompose zonal refractivity variations into amplitudes and phases for observed wave numbers k = 1-4 over the entire altitude range and use the results to analyze atmospheric structure and dynamics. The data set consists of 147 refractivity profiles acquired in December 2000 at summer solstice in the Martian northern hemisphere. The measurements are at an essentially fixed local time (sunrise) and at latitudes from 67° to 70°N. Thermal tides appear to be responsible for much of the observed ionospheric structure from 80 to 220 km. Tides modulate the neutral density, which in turn, controls the height at which the ionosphere forms. The resulting longitude-dependent vertical displacement of the ionosphere generates distinctive structure in the fitted amplitudes, particularly at k = 3, within +/-50 km of the electron density peak height. Our k = 3 observations are consistent with an eastward propagating semidiurnal tide with zonal wave number 1. Relative to previous results, our analysis extends the characterization of tides to altitudes well above and below the electron density peak. In the neutral atmosphere, refractivity variations from the surface to 50 km appear to arise from stationary Rossby waves. Upon examining the full vertical range, stationary waves appear to dominate altitudes below ~75 km, and thermal tides dominate altitudes above this transition region.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Radio science measurements of atmospheric refractivity with Mars Global Surveyor does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Radio science measurements of atmospheric refractivity with Mars Global Surveyor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Radio science measurements of atmospheric refractivity with Mars Global Surveyor will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1009211

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.