CONTRAST: NSF/NCAR GV HIAPER Low Rate (LRT - 1 sps) Navigation, State Parameter, and Microphysics Flight-Level Data - ICARTT Format

This dataset begins with Version 2.0 because it is derived from the second version (labelled Version 1.1) of the LRT .nc dataset (383.012). We did not create ICARTT files from version 1.0. The version numbering is inconsistent because NASA require whole-number versions, but EOL does not.

This update contains corrected 2DC data (CONC2DCA_LWOO, DBAR2DCA_LWOO, and PLWC2DCR_LWOO). No other data has been changed. It was discovered that all particles in a single buffer got time-stamped with the data-system time tag of the end off the buffer. For concentrations above 5-10/L, or when in heavy cloud, the system writes multiple buffers per second so the time-stamp will be very close to accurate. When a buffer spans multiple seconds, all the particles were being binned to the second of the end time-stamp for the buffer. This has now been corrected so data is spread across the time-period of the buffer correctly. This version also uses exact circle fitting for measuring particle size and limits accepted particles to center-in images.

Some processing algorithms have changed since the last release. This version contains:

• recovery factor study modifications for temperature (elements 1 & 2 get a separate recovery factor now)
• humidity / MACH / TAS algorithm updates
• modifications to the wind uncertainty algorithm
• and for 2d processing, the processing didn't change, but extract2d got a new algorithm for determining which records should be rejected and not transferred into the 2d file.