SAFIRE ATR42: Turbulence Data 25 Hz

During the LIAISE field experiment, the French ATR 42 environmental research aircraft of SAFIRE was dedicated to the exploration of the atmospheric boundary layer structure above a heterogeneity surface. The SAFIRE ATR42 aircraft was equipped with a 5-hole nose radome, and several temperature and humidity sensors, for measurements of the three wind components, temperature and humidity at fast rate (25 Hz). Those high frequency measurements allow us to estimate the turbulent moments and to study the turbulence structure above the arid and humid surface, as well as the fine thermodynamical structure.

The turbulence moments are calculated on stabilized legs, (i) after detrending and (ii) after high-pass filtering at cut-off wavelength of approximately 5 km. The two kinds of calculation give access to the homogeneity of the sample and to random and systematic sampling errors.
For all stabilized legs of all processed flights, a set of turbulence moments or characteristics are available, as well as the high rate fluctuations.

The dataset includes two kinds of data:
- Turbulent moments, calculated over each segment, from filtered and unfiltered series. Those are supplied in netcdf files, with one file per flight
- The fluctuations over each segment are also made available (detrended and high-pass filtered series). For this, each flight directory includes a set of netcdf files associated with all segments or legs, with one file per segment.

For those two types of data, one level of data processing are considered named level 2.
- Level 2: Complete files of turbulent moments and fluctuations, using fast humidity measurements from licor and fast temperature from fine-wire.