Surface Layer Flux Sources and Parameterization Failure in Stable Conditions from CASES-99 Data Analysis: Impacts of Intermittent Turbulence its Sources and a Proposed Solution

摘要

This work is comprised of a comprehensive investigation of the evolution and stability of and the turbulent mixing and fluxes within, the stable nocturnal boundary layer (NBL) using the Cooperative Atmosphere-Surface Exchange Study (CASES) instrumented site in south central Kansas and the greatly enhanced in-situ instrumentation to be deployed during CASES-99. It was motivated by the need to establish the role of the NBL and phenomena within the NBL in surface and boundary layer heat and momentum fluxes. We have used the correlative high-resolution measurements of turbulence generation and mixing during CASE S-99 to (1) understand the dynamics and characteristics of turbulence in the NBL, (2) identify the dominant sources of turbulence, and (3) quantify the heat and momentum fluxes, for the improvement of existing parameterization. During the 2 year period of the contract we completed extensive observational analyses and quantification of NBL flux, including data analysis from the Intensive Observational Periods (IOPs). Our research has been extensive and significantly progressed the atmospheric science field's knowledge of the processes contributing to turbulent mixing and transport in the stable NBL and has specifically enabled their more quantitative parameterization, with direct future impacts on the improved numerical simulation of severe dispersion periods.