Characterizing Near Surface Lapse Rates in the White Mountains Region Using High-Resolution Mesonet Data

The Mount Washington Observatory's Near Surface Lapse Rate research project examines the variation of temperature with elevation, known as lapse rates, utilizing the Mount Washington Auto Road Vertical Temperature Profile (ARVP) mesonet dataset spanning from January 2016 to December 2022. Lapse rates, denoting the change in temperature per unit elevation change, are essential in understanding atmospheric dynamics. This study aims to establish baseline lapse rate patterns at different time scales and assess their relation to theoretical adiabatic lapse rates.

In the absence of local or regional data, standard atmosphere lapse rates have often been used. To address this gap, the research establishes average lapse rates and measures their variability at various temporal resolutions. Comparisons are made between the derived average lapse rates, the Dry adiabatic lapse rate of 9.8 degrees Celsius per kilometer, and the moist adiabatic lapse rate of 6.5 degrees Celsius per kilometer.

The methodology involves utilizing the ARVP mesonet, comprised of automatic weather stations situated approximately 1000 ft apart in elevation. The dataset, characterized by its high data quality, undergoes meticulous filtering, including exclusion of extreme temperatures beyond state records. Max daily max temperature (Tmax), average temperature (Tavg), and minimum temperature (Tmin) are analyzed by fitting lines and aggregating into monthly, seasonal, and annual averages. Diurnal temperature variations are also examined through 10-minute intervals.

Key findings reveal distinctive temperature behaviors. Lower elevations experience rapid temperature increases, particularly in the morning following sunrise. Winter lapse rate variations are more pronounced than in summer, with spring and fall acting as transitional periods. Monthly averages indicate differing lapse rate trends from spring to summer. Notably, frontal processes impact lapse rates, especially during winter and spring, contributing to variations.

Overall, this comprehensive analysis demonstrates stable lapse rate patterns over the 7-year study period. The research's outcomes provide valuable insights for ongoing studies involving temperature variations in the White Mountains and the greater New England area. The Mount Washington Observatory's Near Surface Lapse Rate research contributes to a refined understanding of local lapse rate dynamics, thereby enhancing meteorological knowledge and applications.