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Supplementary Information

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Figure SI-1. Animation of wind and potential temperature structure during IOP4 (19-20 October 2013) of the Second Meteor Crater Experiment (METCRAX II) within a 15° azimuth vertical plane through the crater (location in Fig. 1 of Whiteman et al. 2018). Terrain is indicated by a solid black line and rim elevation by a dot-dash line. Off-plane data are projected perpendicularly onto the plane. Data shown are 5-min averages ending at the time indicated, except for tethersonde soundings, which are the closest in time within ±7.5 minutes of the averaging interval midpoint. Left sub-figures: Black vectors are 2D (u,w) winds. TS-B wind profiles (blue vectors) have no w-component and are offset from its plain location (moved closer to the crater). TS-SW is at the dashed vertical line. Winds come from dual-Doppler lidar retrievals, with red triangles marking the lidar locations. The north rim lidar is the x-coordinate origin. Wind data also come from the RIM tower, the BASE tethersonde, and the SSW4 and SSW2 sites. Color contours (see legend) indicate wind speeds within the plane. Right sub-figures: Potential temperature soundings at sites shown in the legend. The reference height for the potential temperatures is the floor of the basin, and potential temperatures are reported in °C. The sloping dashed line is an isothermal lapse rate.

Figure SI-2. Three-hourly rawinsonde vertical profiles of a) temperature and b) horizontal wind vectors from BASE (1695 m MSL) in the period from 1600 MST 19 October to 0700 MST 20 October 2013. [Fig SI02.pdf]

Figure SI-3. Time series of a) 5-minute-mean net radiation R and 30-minute-mean turbulent sensible heat H fluxes at the FAR and NEAR sites on the plain and the FLR site on the crater floor. Local sunset times are 1742, 1742 and 1615 MST, respectively. For comparison of the two sub-figures, values have been plotted at the mid-point of the averaging periods. [energybalance_20170509.eps]

Figure SI-4. Spatial pattern of near-surface horizontal winds (vectors) and temperatures (colored dots, see legend) at a) 2040 and b) 0040 MST from automatic weather stations and the lower levels of towers. 5-min-mean data. [plan_map.png]

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Figure SI-5a. Time-lapse animation of geo-referenced brightness temperature during the 0000-0030 MST period on 20 October 2013, as overlaid on Meteor Crater topography. Adjusted brightness temperature data come from three thermal infrared cameras, two operated side by side on the north rim looking south-southwest and one on the south rim looking north-northeast. Camera locations are shown as white dots in Fig. 10 of Whiteman et al. (2018). Horizontal wind vectors are shown in black at RIM, SSW4 and SSW2 and in white at FLR. Site locations are shown in the Fig. 1 map of Whiteman et al. (2018). The 30-min animation uses thermal infrared photos taken at 2-min intervals.

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Figure SI-5b. Time-lapse animation of geo-referenced brightness temperature fluctuations during the 0000-0030 MST period on 20 October 2013, as overlaid on Meteor Crater topography. Adjusted brightness temperature data come from three thermal infrared cameras, two operated side by side on the north rim looking south-southwest and one on the south rim looking north-northeast. Camera locations are shown as white dots in Fig. 10 of Whiteman et al. (2018). Horizontal wind vectors are shown in black at RIM, SSW4 and SSW2 and in white at FLR. Site locations are shown in the Fig. 1 map of Whiteman et al. (2018). The 30-min animation uses thermal infrared photos taken at 2-min intervals.

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Reference:

Whiteman, C. D., M. Lehner, S. W. Hoch, B. Adler, N. Kalthoff, R. Vogt, I. Feigenwinter, T. Haiden, and M. O. G. Hills, 2018: The nocturnal evolution of atmospheric structure in a basin as a larger-scale katabatic flow is lifted over its rim. J. Appl. Meteor. Climatol., xx, xxx-xxx. doi: , in press.