DLR Falcon aircraft

The DLR Falcon aircraft will conduct about 60 hours of local research flights from the base at Christchurch. It will fly above New Zealands South Island and surrounding oceans in specific patterns crossing the New Zealand Alps.

The research aircraft is equipped with in-situ sensors for meteorology and turbulence measurements and for various trace gases (water vapour, ozone, methane, carbon monoxide, carbon dioxide, nitrous oxide and sulfur dioxide). The QCL (Quantum Cascade Laser Spectrometer) operated by IPA Mainz measures nitrous oxide and carbon monoxide. The Picarro cavity ring down spectrometer measures ozone, methande and carbon dioxide. The CIMS (Chemical Ionization Mass Spectrometer) measures sulfur dioxide. The Waran/CR-2 combination provides water vapour measurements with two different systems based on TDL (tunable diode laser hygrometer) and the high performance chilled mirror hygrometer CR-2.

As a remote sensing instrument the 2 um Doppler wind lidar system samples the disturbed wind field and gravity waves. The wind profiles are retrieved from line-of-sight measurements of the Doppler lidar by the velocity-azimuth display (VAD) technique. The instrument performs a conical step-and-stare scan around the vertical axis with a nadir angle of 20 deg°. Combined with the movement of the aircraft, this results in acycloid scan pattern. The horizontal resolution of the wind profiles (5-10 km) is determined by the time needed for one scanner revolution (24 times 1 or 2 s as accumulation time per scan position, plus 6 s for the scanner motion) and the aircraft velocity (160-240 m/s). The vertical resolution of 100 m is determined by the pulse length of the laser [full width at half maximum (FWHM) = 400 ns (~120 m)] and the nadir angle of 20 deg. Nadir pointing measurements only without scanningmode will provide vertical winds in a horizontal resolution of ~ 200 m. Additionally, the aerosol backscatter maps out the cloud field over the Southern Alps. Cloud mapping is important as clouds may alter the generation of vertically propagating gravity waves. Expected cloud types include lenticular (liquid or ice) clouds, undulating alto-stratus, and shallow convective clouds.

Middle atmosphere lidar

The Rayleigh-Raman lidar by DLR is a ground-based system installed at NIWA station in Lauder, Central Otago. This is on South Island below the Falcon flight track. The system is housed in a 11-foot container and consists of a laser emitter, trigger electronics, receiving telescopes, detectors and controlling software. It will provide night-time measurements of density and temperature (5-105 km) and aerosol (5-35 km). Data analysis will be published real-time and quicklook plots will be available on this website. The lidar system emits at 532 nm (12 W) and employs a 63 cm aperture telescope for reception. The field of view is 200 microrad (Rayleigh/Raman). The resolution is 500 m to 2 km and 5-60 min depending on altitude.

Radiosondes

Radiosondes are launched in the period from June 14 - July 20, 2014. Radiosonde measurements provide wind, temperature and humidity from the surface up to about 30 km altitude. This allows to derive the tropopause height and characterize gravity waves in the troposphere and stratosphere. In coordination with other radiosonde stations deployed during Deepwave, different launch techniques are applied: Simultaneous launches of two balloons with different gas fillings, and series of balloon launches every 90 or 120 min during IOPs. A total of 100 balloons of 600 g are launched from the NIWA station in Lauder, Central Otago. One Väisälä radiosonde station with 80 sondes is provided by the Ludwig Maximilian University Munich and one GRAW radiosonde station is brought by the University of Innsbruck with 20 sondes.