Comparison of Vertical Soundings and Sidewall Air Temperature Measurements in a Small Alpine Basin

Abstract

Tethered balloon soundings from two sites on the floor of a 1-km-diameter limestone sinkhole in the eastern Alps are compared with pseudovertical temperature “soundings” from three lines of temperature dataloggers on the basin's northwest, southwest, and southeast sidewalls. Under stable nighttime conditions with low background winds, the pseudovertical profiles from all three lines were good proxies for free air temperature soundings over the basin center, with a mean nighttime cold temperature bias of about 0.4°C and a standard deviation of 0.4°C. Cold biases were highest in the upper basin where relatively warm air subsides to replace air that spills out of the basin through the lowest-altitude saddle. On a windy night, standard deviations increased to 1°–2°C. After sunrise, the varying exposures of the dataloggers to sunlight made the pseudovertical profiles less useful as proxies for free air soundings. The good correspondence between sidewall and free air temperatures during high-static-stability conditions suggests that sidewall soundings can be used to monitor temperatures, temperature gradients, and temperature inversion evolution in the sinkhole. Sidewall soundings can produce more frequent profiles at lower cost than can tethersondes or rawinsondes, and extension of these findings to other enclosed or semienclosed topographies may enhance future basic meteorological research or support applications studies in agriculture, forestry, air pollution, and land use planning.

The Atmospheric Boundary Layer during Wintertime Persistent Inversions in the Grenoble Valleys

“…It follows that the temperature difference between the top and the bottom of the ABL is well estimated by the difference in temperature between any high-elevation station and any lowelevation station, and that the latter may be indicative of the ABL static stability. This is consistent with the results of Whiteman et al (2004) who have shown that temperature vertical profiles can be well-approximated by pseudovertical profiles obtained from temperature stations on the sidewalls, in strongly stable and low synoptic wind conditions.…”

Foehn Winds in the McMurdo Dry Valleys, Antarctica: The Origin of Extreme Warming Events*

“…It is difficult to accurately estimate the inversion strength and depth of the near-surface cold pools in the MDVs because vertical profile observations during winter are unavailable. Whiteman et al (2004) demonstrate that valley sidewall temperatures can be used in place of freeair vertical profile measurements under clear and stable conditions. Accordingly, comparisons of temperatures on the valley sidewalls in the MDVs to those on the valley floor would suggest that cold pooling may be in the order of ;108C in the Taylor Valley [Lake Fryxell (TF); Lake Bonney (TB)], ;158C in the Wright Valley [Lake Vanda (WV)], and ;208C in the Victoria Valley (VV).…”

“…6). This is a combination of forced channeling owing to the westerly component of the upstream flow but also pressure-driven channeling (see Whiteman and Doran 1993) To isolate the synoptic configuration associated with foehn in the MDVs, composites of SLP field and wind vectors for 2006 and 2007 were constructed based on 172 foehn days recorded at three or more valley surface stations, compared to the 172 nonfoehn days. There were 398 total nonfoehn days through 2006 and 2007, 172 were selected to match the sample number of foehn days.…”

Temperature and humidity conditions of Macocha Abyss

“…Whiteman et al (2004b) conducted vertical soundings and sidewall air temperature measurements in a limestone sinkhole (valley) in karst plateau on Hetzkogel (Austria).…”