@prefix skos: <http://www.w3.org/2004/02/skos/core#> .
@prefix ns0: <https://gcmd.earthdata.nasa.gov/kms#> .

<https://gcmd.earthdata.nasa.gov/kms/concept/6e0ee015-7fde-40bf-af5a-5b95ad966e32>
  skos:prefLabel "P - R"@en ;
  a skos:Concept ;
  skos:narrower <https://gcmd.earthdata.nasa.gov/kms/concept/c9cac43e-c3f1-4ec9-a477-da20b0c5b267> .

<https://gcmd.earthdata.nasa.gov/kms/concept/c9cac43e-c3f1-4ec9-a477-da20b0c5b267>
  ns0:altLabel [ ] ;
  skos:broader <https://gcmd.earthdata.nasa.gov/kms/concept/6e0ee015-7fde-40bf-af5a-5b95ad966e32> ;
  skos:prefLabel "PROBE"@en ;
  skos:inScheme <https://gcmd.earthdata.nasa.gov/kms/concepts/concept_scheme/projects> ;
  skos:definition """The Division of Atmospheric Research took part in ARM's TOGA COARE
(Tropical Ocean Global Atmosphere/Coupled Ocean Atmosphere Response
Experiment.) PROBE experiment at Kavieng, New Guinea (2.5S, 150.8W) in
January - February, 1993. This afforded an opportunity to use the new
radiometer alongside the CSIRO Mark II radiometer in a direct
comparison. The Division's 0.532 m lidar was also used, and the data
obtained on cirrus clouds, as well as some altocumulus, will be
analyzed with the LIRAD method. The PROBE will also provide excellent
radiosonde data every six hours, together with continuous microwave
data of water vapour column and cloud liquid water column observations
from the National Oceanic and Atmospheric Administrations's (NOAA)
Wave Propagation Laboratory (WPL). The water vapour column data will
be invaluable in allowing for any variations in water vapour radiance
and transmittance at times between radiosonde observations.

        A preliminary analysis of the data indicates the variability
of the cirrus and its considerable geometrical depth at times and also
the persistence of the cirrus cover. Particularly interesting was an
apparent diurnal variation in both the cirrus cover and the optical
depth with a maximum at about midday.

        The ARM filter radiometer was run for about 70% of the time on the
        8.62 m filter; however, for some periods, the radiometer was
        run with the 10.86 m filter enabling a direct comparison with
        the Mark II radiometer which used a 10.84 m filter. As the
        input radiance is chopped against a 40C blackbody, the zero
        radiance when viewing liquid nitrogen actually gives a large
        negative signal; whereas, the zero voltage occurs when the
        input radiance is from a 40C blackbody. The responses of the
        two radiometers to various clouds are quite evident. The water
        vapour radiance is large, which is typical for the
        tropics. Periodically, there are either cirrus radiances or
        larger cumulus radiances superposed. Also evident is the
        superior behaviour of the new ARM radiometer. The two
        radiometer apertures were equal in the comparison; however,
        the ARM and Mark II time-constants were 1 second and 5
        seconds, respectively. By looking at the signal and noise
        levels during the calibration episodes in!  more detail, we
        calculate the minimum detectable radiances (MDR) of the two
        instruments as 4.9 x hz-1/2(ARM) and 6.8 X hz-1/2(CSIRO Mark
        II).

      Contact:

      C. Martin Platt (Lead Scientist)
      mplatt&#64net2000.com.au

      For more information,
      link to "http://www.arm.gov/docs/iops/past/afteriop_probe1993.html"

      [Summary provided by ARM]"""@en ;
  a skos:Concept .