Content - Emerging Activities

Emerging SPARC activities

FISAPS - Fine Scale Atmospheric Processes and Structures


Activity leaders

The initial co-chairs of FISAPS are:

Marvin Geller
Stonybrook University, USA

Hye-Yeong Chun
Yonsei University, Korea

Peter Love
University of Tasmania, Australia 


Activity description

Many atmospheric phenomena that influence large-scale dynamics occur on vertical scales less than one kilometre. This activity will utilise operational high vertical resolution radiosonde data (HVRRD) and other sounding data to study several of these phenomena. Studies that have already utilised these data include SPARC's gravity wave activity, which focusses on spatial and temporal variations of gravity waves in the troposphere and lower stratosphere. Subsequently the data have been used for various other important phenomena such as the fine structure of the extra-tropical tropopause and also to characterise the planetary boundary layer for comparison with climate models. With the advent of even higher resolution made possible by the transition of radio-location sondes to GPS sondes, studies of turbulence are now conceptually possible. The turbulence data derived from high-resolution sondes could be an invaluable resource for research and forecasting of aviation turbulence. Numerous other applications have been explored and continue to emerge.  Modelling has evolved to the point where realistic modelling of wave transitions to turbulence is now being carried out.  It is important to note that while such HVRRD are available at hundreds of stations in the world, only a small fraction are conveniently available to the research community.  One of the prime goals of this activity is to improve the archiving of these data so that more are available to the worldwide research community.  With the higher vertical resolution of GPS soundings, GPS data will also be valuable for this activity, as will aircraft and other observations. 

The objective of this activity is to realise the full potential of large volumes of HVRRD archived worldwide. Providing coordination for the growing community of HVRRD users will promote the development of innovative applications of HVRRD by facilitating the sharing of expertise on analysis techniques, data handling, and technical capabilities and limitations. This sharing of expertise will be of similar benefit for the refinement and improvement of existing fields of research using HVRRD. Due to restrictions on access to HVRRD, previous studies have been limited to relatively small geographic coverage. This activity aims to address this limitation by two means, first, by coordinating broader regional intercomparisons and global studies that bring together researchers from the global HVRRD community. The second is to provide improved access to existing HVRRD to the research community.

While the initial focus of FISAPS will be on fine-scale dynamical structures, it is anticipated that FISAPS may expand its scope to fine-scale constituent structures and processes.  It is clear that troposphere and stratosphere observations of atmospheric constituents show considerable fine-structure, yet chemistry-transport models display relatively smooth structures.  Quantifying how the absence of fine-scale structures in modelled chemical constituents affects computed chemical reaction rates would be a focus of this expanded activity.

An initial FISAPS project will be the preparation of a review article on research uses of HVRRD. Finalisation of this review will probably require a small meeting of the principal authors, who will likely form the core of the project steering group.  We solicit statements of interest of participation in FISAPS.  In the coming months, a suggested list of participants of the initial FISAPS Steering Group will be submitted to the SPARC Scientific Steering Group for their approval.


Published results

SPARC Newsletter No. 47, 2016, p. 8: FISAPS: An Emerging SPARC Activity, by M. Geller, H.-Y. Chun, and P. Love