Evaluation of the MODIS LAI algorithm at a coniferous forest site in Finland

Yujie Wang (Corresponding Author), Curtis E. Woodcock, Wolfgang Buermann, Pauline Stenberg, Pekka Voipio, Heikki Smolander, Tuomas Häme, Yuhong Tian, Jiannan Hu, Yuri Knyazikhin, Ranga B. Myneni

    Research output: Contribution to journalArticleScientificpeer-review

    203 Citations (Scopus)

    Abstract

    Leaf area index (LAI) collected in a needle-leaf forest site near Ruokolahti, Finland, during a field campaign in June 14–21, 2000, was used to validate Moderate Resolution Imaging Spectroradiometer (MODIS) LAI algorithm. The field LAI data was first related to 30-m resolution Enhanced Thermal Mapper Plus (ETM+) images using empirical methods to create a high-resolution LAI map. The analysis of empirical approaches indicates that preliminary segmentation of the image followed by empirical modeling with the resulting patches, was an effective approach to developing an LAI validation surface. Comparison of the aggregated high-resolution LAI map and corresponding MODIS LAI retrievals suggests satisfactory behavior of the MODIS LAI algorithm although variation in MODIS LAI product is higher than expected. The MODIS algorithm, adjusted to high resolution, generally overestimates the LAI due to the influence of the understory vegetation. This indicates the need for improvements in the algorithm. An improved correlation between field measurements and the reduced simple ratio (RSR) suggests that the shortwave infrared (SWIR) band may provide valuable information for needle-leaf forests.

    Original languageEnglish
    Pages (from-to)114 - 127
    Number of pages14
    JournalRemote Sensing of Environment
    Volume91
    Issue number1
    DOIs
    Publication statusPublished - 2004
    MoE publication typeA1 Journal article-refereed

    Keywords

    • coniferous forest site
    • Finland
    • MODIS LAI
    • leaf area index
    • MODIS algorithm
    • algorithms

    Fingerprint

    Dive into the research topics of 'Evaluation of the MODIS LAI algorithm at a coniferous forest site in Finland'. Together they form a unique fingerprint.

    Cite this