Collecting, Quantifying, and Characterizing Surface Convective Energy Fluxes on Mount Washington Summit

Over the years there have been an increasing number of buildings and structures on the summit of Mount Washington with unknown effects to the quality of measurements taken by the Mount Washington Observatory. This study is an exploratory investigation attempting to quantify the impact of these structures on measurements of temperature, dewpoint temperature, and wind speed taken at multiple locations across the summit. It was hypothesized that the spatial variability of measured air and dewpoint temperatures on the Mount Washington summit does not statistically impact the resulting computations of convective surface heat fluxes to within expected accuracies and precisions and therefore such measurements can be collected in any reasonable location around the summit under all expected weather conditions. To test this hypothesis, measurements of the Bowen Ratio were taken 3 times a day on the windward and leeward sides of 3 structures on the summit, with the current measurement location as the reference point. Sling psychrometers and Kestrel 5000s were used to measure temperature, dewpoint temperature, and wind speed at each location. The resulting calculations of the Bowen Ratio were inconclusive, with all data falling within the noise range due to instrument sensitivity and unknown aerodynamic transfer coefficients for heat and moisture of a mountain top environment. This study demonstrates the need for further research on aerodynamic transfer coefficients for heat and moisture of a mountain top environment to properly apply the Bowen Ratio.