Hard target UV lidar measurements of isoprene mixing ratios and emission rates from eucalyptus trees.
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.
Roberts
David Edward
DE
CSIR National Laser Centre, PO Box 395, Pretoria 0001, South Africa. troberts@csir.co.za
Du Plessis
Anton
A
Ombinda-Lemboumba
Saturnin
S