Gerry BAGTASA^1*, Cheng LIU^1,2, Nobuo TAKEUCHI¹, Hiroaki KUZE¹, Suekazu NAITO³, Akihiro SONE⁴, and Hirofumi KAN⁴

¹Center for Environmental Remote Sensing, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan
²Science and Technology University of China, Hefei 230026, China
³Chiba Prefectural Environmental Research Center, 1-88 Iwasaki-nishi, Ichihara, Chiba 290-0046, Japan
⁴Hamamatsu Photonics K.K., 5000 Hirakuchi, Hamamatsu, Shizuoka 434-8601, Japan

(Received September 1, 2006; Accepted September 27, 2006)

Lidar data observed by two continuously operated portable automated lidar (PAL) systems and images from the visible and thermal infrared channels of the advanced very high resolution radiometer (AVHRR) sensor on board the NOAA16 satellite are employed for the characterization of cloud heights and cloud types. The PAL systems are located in Chiba and Ichihara city areas, separated by approximately 10 km. Measurements from October 2003 to March 2005 reveal that monthly averages of cloud base height and cloud cover ratio show good agreement between the two sites. The characteristics of the vertical (Chiba) and slant (Ichihara) measurements are also discussed. The PAL data are used to adjust threshold values of a cloud-type classification method in split-window data of NOAA16-AVHRR. Comparisons between the lidar signals and the cloud classification results from the concurrent AVHRR images show that the classification method can reasonably be applied to this mid-latitude case, although the split-window technique was originally developed for tropical clouds.

Key words: portable automated lidar, Mie lidar, cloud, satellite, NOAA16-AVHRR, cloud detection, cloud type classification

^*Corresponding author. E-mail address: gerry@graduate.chiba-u.jp