39 research outputs found
Forecasting water vapour above the sites of ESO's Very Large Telescope (VLT) and the Large Binocular Telescope (LBT)
Water vapour in the atmosphere is the main source of the atmospheric opacity
in the infrared and sub-millimetric regimes and its value plays a critical role
in observations done with instruments working at these wavelengths on
ground-based telescopes. The scheduling of scientific observational programs
with instruments such as the VLT Imager and Spectrometer for mid Infrared
(VISIR) at Cerro Paranal and the Large Binocular Telescope Interferometer
(LBTI) at Mount Graham would definitely benefit from the ability to forecast
the atmospheric water vapour content. In this contribution we present a study
aiming at validating the performance of the non-hydrostatic mesoscale Meso-NH
model in reliably predicting precipitable water vapour (PWV) above the two
sites. For the VLT case we use, as a reference, measurements done with a Low
Humidity and Temperature PROfiling radiometer (LHATPRO) that, since a few
years, is operating routinely at the VLT. LHATPRO has been extensively
validated on previous studies. We obtain excellent performances on forecasts
performed with this model, including for the extremely low values of the PWV
(<= 1 mm). For the LBTI case we compare one solar year predictions obtained
with the Meso-NH model with satellite estimates again obtaining an excellent
agreement. This study represents a further step in validating outputs of
atmospheric parameters forecasts from the ALTA Center, an operational and
automatic forecast system conceived to support observations at LBT and LBTI.Comment: 15 pages, 8 figures, 11 tables, MNRAS accepted on 28 November 201