TITLE: ACEASIA_YulinPAR AUTHOR(S): Michael H. Bergin and Jin Xu 200 Bobby Dodd Way, Atlanta, GA 30332 Phone: 404-894-9723 Fax: 404-894-8266 E-mail: mike.bergin@ce.gatech.edu, jin.xu@ce.gatech.edu 1.0 DATA SET OVERVIEW: Photosynthetically Active Radiation (400 - 700 nm) (PAR) was measured, and data were collected every minute. 2.0 INSTRUMENT DESCRIPTION: Li-Cor Photosynthetically Active Radiation (PAR) Sensors (400 - 700 nm). 3.0 DATA COLLECTION AND PROCESSING: Two Li-COR photosynthetically Active Radiation (PAR) sensors were used parallely to continuously measure the downward irradiance from 400nm-700nm, which is the spectral range used by plants for photosynthesis. The sensors were calibrated by the LI-COR, inc. before the field campaign. The sensors are cosine corrected (follows Lambert's cosine law) to allow measurements of flux densities through a plane surface from all angles of a hemisphere most accurate. The error is typically less than 5% for angle less than 80 degree from the normal axis of the sensor [LI-COR Radiation Sensors Instruction Manual]. During the field campaign, two sensors agreed with each within 1%. 4.0 DATA FORMAT: Tab delimited ASCII 5.0 DATA REMARKS: DATA VERSION = 1.0 (August 27, 2001), PRELIMINARY REMARKS = PAR - Photosynthetically Active Radiation (400 - 700 nm), two par sensors were used side by side (PAR1, PAR2) REMARKS = Data point Date/Time provided in UTC 6.0 REFERENCES: LI-COR Radiation Sensors Instruction Manual