We present the Gattini project: a multisite campaign to measure the optical sky properties above the two high altitude
Antarctic astronomical sites of Dome C and Dome A. The Gattini-DomeC project, part of the IRAIT site testing
campaign and ongoing since January 2006, consists of two cameras for the measurement of optical sky brightness, large
area cloud cover and auroral detection above the DomeC site, home of the French-Italian Concordia station. The cameras
are transit in nature and are virtually identical except for the nature of the lenses. The cameras have operated
successfully throughout the past two Antarctic winter seasons and here we present the first results obtained from the
returned 2006 dataset. The Gattini-DomeA project will place a similar site testing facility at the highest point on the
Antarctic plateau, Dome A, with observations commencing in 2008. The project forms a small part of a much larger
venture coordinated by the Polar Research Institute of China as part of the International Polar Year whereby an
automated site testing facility called PLATO will be traversed into the DomeA site. The status of this exciting and
ambitious project with regards to the Gattini-DomeA cameras will be presented.
Nitric oxide, which reacts catalytically to destroy ozone, can be produced in great abundance in the middle atmosphere during energetic particle precipitation triggered by solar storms. During the Antarctic winter, the strong polar vortex can rapidly transport nitric oxide downward, and this process has been identified as a mechanism that can link ozone recovery in the upper stratosphere with solar activity. As part of the Sun Earth Connection programme at the British Antarctic Survey (BAS), a new, state-of-the-art microwave radiometer is being developed in collaboration with the Max-Planck Institute (MPI) and the Norwegian Polar Institute (NPI) to simultaneously measure profiles of ozone and nitric oxide between 30 and 80 km deep within the Antarctic polar vortex. Operating in the 250 GHz spectral region, the semi-autonomous instrument will be coupled to moderate- and high-resolution chirp spectrometers to provide simultaneous spectra of the nitric oxide and ozone. In addition, a second local oscillator will be used to periodically examine carbon monoxide at 230.538 GHz to infer the vertical descent rate within the Antarctic vortex. Here, we present the science rationale for the observation programme as well as the instrument specifications, design and performance.
The University of Illinois Fe (iron) Boltzmann temperature lidar was operated at the South Pole (90°S) from November 1999 to October 2001, and then at the Rothera Station (67.5°S, 68.0°W) from December 2002 to March 2005. This lidar transmits two UV wavelengths at 372 and 374 nm, and is able to measure the middle and upper atmosphere temperature, Fe density, polar mesospheric clouds (PMC), and polar stratospheric clouds (PSCs). In this paper, we analyze the PSC data collected in the winters and springs of 2003 and 2004 at Rothera, and compare them with the PSC data collected at the South Pole in the 2000 and 2001. PSCs were observed in the range of 15-28 km during the seasons from May/June to October at both locations. The PSC backscatter ratio, width, and altitude at Rothera are comparable to those at the South Pole. However, Rothera PSCs occur less frequently (~17.7%) and in shorter periods, compared to PSCs at the South Pole (~64.9%). At Rothera, PSC occurrence frequency in 2004 is only half of that in 2003, which is likely due to warmer stratospheric temperatures in 2004 associated with changes of the polar vortex. These are the first ground-based lidar observations of PSC at Rothera, and also the first in West Antarctica.