Parameterization of sparse vegetation in thermal images of natural ground landscapes

Eyal Agassi*, Nissim Ben-Yosef

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

3 Scopus citations

Abstract

The radiant statistics of thermal images of desert terrain scenes and their temporal behavior have been fully understood and well modeled. Unlike desert scenes, most natural terrestrial landscapes contain vegetative objects. A plant is a living object that regulates its temperature through evapotranspiration of leaf stomata, and plant interaction with the outside world is influenced by its physiological processes. Therefore, the heat balance equation for a vegetative object differs from that for an inorganic surface element. Despite this difficulty, plants can be incorporated into the desert surface model when an effective heat conduction parameter is associated with vegetation. Due to evapotranspiration, the effective heat conduction of plants during daytime is much higher than at night. As a result, plants (mainly trees and bushes) are usually the coldest objects in the scene in the daytime while they are not necessarily the warmest objects at night. The parameterization of vegetative objects in terms of effective heat conduction enables the extension of the desert terrain model for scenes with sparse vegetation and the estimation of their radiant statistics and their diurnal behavior. The effective heat conduction image can serve as a tool for vegetation type classification and assessment of the dominant physical process that determinate thermal image properties.

Original languageEnglish
Pages (from-to)2910-2917
Number of pages8
JournalOptical Engineering
Volume36
Issue number10
DOIs
StatePublished - Oct 1997

Keywords

  • Evapotranspiration
  • Heat balance equations
  • Heat conduction
  • Reflective images
  • Thermal infrared images
  • Vegetation

Fingerprint

Dive into the research topics of 'Parameterization of sparse vegetation in thermal images of natural ground landscapes'. Together they form a unique fingerprint.

Cite this