title: Hard target UV lidar measurements of isoprene mixing ratios and emission rates from eucalyptus trees.
abstract: The application of UV lidar to measure isoprene concentrations for environmental studies has been investigated. With a hard target lidar system at 223 nm, isoprene mixing ratios above eucalyptus trees were measured with a sensitivity of about 1 ppbv. Results over a long timescale were compared with an existing model of isoprene emission for a wide range of temperature and sunlight values. Fast time dependent results yielded a leaf emission rate of 25 microg g(-1) hour(-1), consistent with emission from other eucalyptus species. Requirements for development of the system for range resolved isoprene number density measurements using atmospheric backscatter lidar are discussed.
authors.affiliation: CSIR National Laser Centre, PO Box 395, Pretoria 0001, South Africa. troberts@csir.co.za
authors.forename: David Edward
authors.initials: DE
authors.lastname: Roberts
authors.forename: Anton
authors.initials: A
authors.lastname: Du Plessis
authors.forename: Saturnin
authors.initials: S
authors.lastname: Ombinda-Lemboumba