Pseudovertical Temperature Profiles in a Broad Valley from Lines of Temperature Sensors on Sidewalls

Pseudovertical temperature “soundings” from lines of inexpensive temperature sensors on the sidewalls of Utah’s Salt Lake valley are compared with contemporaneous radiosonde soundings from the north, open end of the valley. Morning [0415 mountain standard time (MST)] soundings are colder, and afternoon (1615 MST) soundings are warmer than radiosonde soundings because of warm and cold boundary layers that form over the slopes. Cross-valley temperature differences occur between east- and west-facing sidewalls because of differing insolation. Differences in vertically averaged pseudovertical and radiosonde temperatures are generally within 1°C, with a standard deviation of 2°–3°C. The pseudovertical soundings are especially good proxies for radiosondes in winter. The sounding comparisons identified along-valley differences in temperature, inversion depth, and lapse rate that have led to hypotheses concerning their causes, to be evaluated with future research. The low cost and much better time resolution of the pseudovertical soundings suggest that such lines will be a useful supplement to valley radiosondes and will have significant operational advantages if available in real time. Lines of surface-based sensors will prove useful in identifying intravalley meteorological differences and may be used to estimate free-air temperature structure in other valleys where radiosondes are unavailable.