Owned by the US National Science Federation (NSF) and operated by the US National Center for Atmospheric Research (NCAR), the aircraft flew from Hobart Airport over the Southern Ocean to study the interactions between clouds and particles naturally produced by the ocean, like sea salt, as part of the SOCRATES – Southern Ocean Clouds, Radiation, Aerosol Transport Experimental Study – research project.
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“There will be about 16 flights and they will provide detailed information on the thermal and physical properties of different clouds,”Australian Antarctic Division atmospheric scientist, Dr Simon Alexander, said ahead of the Gulfstream’s visit.
SOCRATES is an international and multi-agency program which, according to the Australian Antarctic Division, “aims to gain deeper insights into how clouds form over the Southern Ocean, what they’re made of, and how they affect the atmospheric energy balance in the region (heat coming into the atmosphere versus heat going out).”
The Gulfstream, dubbed HIAPER, for High-performance Instrumented Airborne Platform for Environmental Research, used Hobart as a base to fly a series of flights at various altitudes between 500 and 20,000ft above the ocean surface carrying a range of instrumentation including radar, lidar, radiometers and cloud droplet probes, while also dispensing ‘dropsondes‘ – air droppable sensors that feature pressure and humidity sensors, a GPS receiver and radio transmitter.
VIDEO – This 2009 video explains how ‘dropsondes’ are deployed.
The CSIRO’s research vessel the RV Investigator and the Australian Antarctic Division’s Aurora Australis have also been involved in the SOCRATES mission, similarly equipped with instrumentation to monitor clouds and aerosols in the Southern Ocean.
“A number of the flights will occur at the same time as the ships are traversing the ocean.
“This work will help us to determine how accurate satellite measurements are, calibrate them accordingly, and then extend these results to the whole Southern Ocean.”
The HIAPER Gulfstream, registered N677F, first arrived in Hobart on January 10 and is normally based at Boulder, Colorado, where it arrived home on March 1. This video explains some of the aircraft’s unique modifications and capabilities.
The Gulfstream V is normally a long-range corporate jet that typically seats up to 14 passengers in leather and walnut comfort.
But the basic Gulfstream platform in its many variants has been widely adapted for special missions roles, from search and rescue to airborne early warning. The Royal Australian Air Force, for example, is set to take delivery of five Gulfstream G550s heavily modified for intelligence, surveillance, reconnaissance and electronic warfare missions.