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7191 - MTM - USU Mesospheric Temp Mapper CCD Imager
Instrument Type: Instrument > OpticalInstrument > Imager
Observatory: None
Observation Site: None
Operating Mode:

Instrument Page: MTM

The Utah State University (USU) CEDAR Mesospheric Temperature Mapper (MTM) is a mobile CCD imager that has been operated in several mid and low latitude locations since its construction was completed in 1996. The imager was built to investigate mesospheric temperature and wave induced variability using the [OH] emission (mean altitude 87 km). In March of 1996 it was tested at Bear Lake Observatory (BLO) (41.933N, 111.417W, 1981 m) and took data at BLO between 7-18 Oct 1996, 4-15 May 1997, and 4 Aug - 24 Sep, 1998. For a year between 11 June 1997 and 2 June 1998, the MTM took data alongside the Colorado State University Na Temperature lidar at Fort Collins, Colorado (40.590N, 105.140W, 1570 m). It was moved to the Starfire Optical Range (SOR) near Albuquerque, New Mexico (34.9639N, 106.4619W), and took data from October 1998 to Dec 1999 alongside the University of Illinois Wind Temperature lidar and all-sky imager and University of Western Ontario Meteor radar. The MTM was then upgraded at USU to include a capability to measure mesospheric temperature using the [O2] nightglow emission (mean altitude 94 km) as well as the [OH] emission. It was then tested and operated at BLO during the period Oct 2000-June 2001. Most recently it was deployed to Maui, Hawaii (20.75N, 156.24W) to take data from October 2001 until the present. The latter data (KINDAT=17087 for OH and KINDAT=17094 for O2) are currently available as nightly mean determinations of [OH] and [O2] rotational temperatures centered at 87 and 94 km, respectively. These data also provide relative band intensities. Higher temporal resolution data are available on request to USU. They start in 2002 to coincide with the TIMED satellite instrumentation deployment. The USU MTM is a CCD imager that measures the hydroxyl [OH] Meinel nightglow in the (6,2) rotational band and the o2 (0,1) molecular oxygen band, both emissions occurring in the near infrared (NIR). The [OH] rotational temperature is derived from the intensity ratio of the P1(4)/P1(2) lines within the (6,2) rotational band. The rotational temperature should be close to the atmospheric temperature under normal equilibrium conditions. The [OH] emission layer is centered near 87 km (+/-2 km) with a thickness of about 8 km. The O2 emission originates at somewhat higher mean altitude of 94 km but has a similar effective layer thickness (FWHM) of about 8 km. Together these measurements permit the investigation of mesospheric temperature variability at two closely spaced but separate regions important for wave-induced (gravity wave, tides and planetary wave) as well as seasonal and longer term variations.