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Hess et al. 1977
Hess, S.L., Henry, R.M., Leovy, C.B., Ryan, J.A. and Tillman, J.E. (1977). Meteorological results from the surface of Mars: Viking 1 and 2. Journal of Geophysical Research 82: doi: 10.1029/JB082i028p04559. issn: 0148-0227.

We deal here primarily with the surface meteorological data for both Viking landers during the nominal missions (44 sols for lander 1 and 61 sols for lander 2). The diurnal patterns of wind, temperature, and pressure were strongly similar from sol to sol, as was expected in the summer. The chief characteristics of the wind data are that winds were light (a few meters per second), with a complex hodograph at VL-1 dominated by counterclockwise turning of the wind and a simpler hodgraph at VL-2 marked by clockwise turning of the wind. The repetitive pattern of wind has begun to break down at VL-2 with advancing season, and several episodes of protracted northeasterly winds have occurred. Some of these are associated with lower than normal tempertures. Examples are given of wind and temperature traces over short periods, illustrating the effects of convection, state stability, and lander interference. We present a theoretical argument based upon the horizontal scale dictated by heating of slopes and upon vertical mixing of momentum to explain the different sense of rotation of the wind vectors at the two sites. Analysis of the semidiurnal pressure oscillation suggests that absorption of solar radiation is an important thermal drive but that convective heat flux from the surface is also significant. The seasonal variation of pressure extending past the end of the nominal missions shows a decrease of pressure to a minimum at L8?149¿ with a rapid rise thereafter. This is clearly due to condensation and sublimation of CO2 on and from the southern polar cap.

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Journal
Journal of Geophysical Research
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American Geophysical Union
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