The atmospheric transparency measured with a LIDAR system at the   Telescope Array experiment
  An atmospheric transparency was measured using a LIDAR with a pulsed UV laser (355nm) at the observation site of Telescope Array in Utah, USA. The measurement at night for two years in $2007\sim 2009$ revealed that the extinction coefficient by aerosol at the ground level is $0.033^{+0.016}_{-0.012} \rm km^{-1}$ and the vertical aerosol optical depth at 5km above the ground is $0.035^{+0.019}_{-0.013}$. A model of the altitudinal aerosol distribution was built based on these measurements for the analysis of atmospheric attenuation of the fluorescence light generated by ultra high energy cosmic rays. 
Takayuki Tomida, Yusuke Tsuyuguchi, Takahito Arai, Takuya Benno,   Michiyuki Chikawa, Koji Doura, Masaki Fukushima, Kazunori...
astro-ph.IM physics.ao-ph physics.ins-det