ABSTRACT
Quantification of near-surface atmospheric fluxes (hereafter AFs) is one of the oldest and most important aspects of environmental fluid dynamics (EFD), as these fluxes represent the transport of mass, momentum, and energy across boundaries of interest that are critical to human activities. In modeling, often, mean advective fluxes can be calculated directly using different (averaged/filtered) forms of the fundamental transport equations; however, the remaining turbulent flux terms represent the classic turbulence closure problem (Pope, 2000). The advent of a number of critical pieces of instrumentation has resulted in a greatly improved ability to probe atmospheric fluxes and understand the associated governing physical processes. Partly as a result of the increased availability of this instrumentation, there has also been a great increase in the number of projects and applications focusing on the measurement of atmospheric fluxes. With this increased activity, a need has developed for resources to aid students and researchers entering in this area. This chapter attempts to outline a practical methodology that can be utilized to aid researchers wishing to make reliable flux measurements in the atmospheric surface layer to test specific hypotheses related to EFD applications. Because of the depth of any individual aspect of the subject areas discussed later, it is impossible to provide a complete description. However, references are provided to useful resources where further details may be found. Finally, given the importance of understanding the linkages between atmospheric simulation and flux measurements, the chapter also provides guidance for integrating
modern flux modeling techniques and measurements with particular attention given to integration of measurements with large eddy simulations (LES).
