Applications - Surface Based Remote Sensing of the Atmospheric Boundary Layer - page 72

Chapter 4
Applications
4.1 Introduction
This chapter gives an overview of some characteristic applications of surface-based
remote-sensing instruments, which have been described in the previous chapter, in
the field of boundary layer meteorology. Today, results from boundary layer remote
sensing are used, e.g. for basic research on vertical and horizontal exchange pro-
cesses in the boundary layer, for air quality assessment, and for energy meteorology.
The spectrum of application ranges from qualitative measurements for the detection
of the overall vertical layering of the ABL (Section 4.2 ) over quantitative measure-
ments of the vertical distribution of a variety of atmospheric parameters (Section
4.3 ) and fluxes (Section 4.4 ) to the investigation of certain three-dimensional flow
systems in the ABL (Section 4.5 ).
The selected examples give an impression of the present state and abilities of
experimental boundary layer research. Being examples, they do not represent a com-
plete overview of all possible applications. This is not only due to the limited space
in the present topic but also due to the still rapidly ongoing developments in this
field. The outlook in the concluding chapter, which follows after this one, will try to
shed light on some of the most recent achievements.
Most of the presented applications refer to vertical profiling and sounding. This
is because the state of the atmospheric boundary layer is mainly determined by its
vertical structure and the vertical gradients of the atmospheric variables in this layer.
Nevertheless, horizontal remote sensing such as tomography, scintillometry, DOAS,
and FTIR will be mentioned where appropriate.
4.2 Vertical Layering of the ABL
The vertical layering of the ABL has an important influence on the atmosphere-
geosphere interaction. Here, geosphere comprises the sphere of human activities,
the biosphere, hydrosphere, cryosphere, and the solid Earth. The state of the ABL
is crucial for exchange processes between the geosphere and the atmosphere as the
layering of the ABL enables, prevents, or modifies vertical and horizontal transports