Chakir Adnane auteur aut IRD Frison P. L. auteur aut IRD Villard L. auteur aut IRD Ouaadi N. auteur aut IRD Fanise Pascal auteur aut IRD Saïd K. auteur aut IRD Le Dantec V. auteur aut IRD Zoubair R. auteur aut IRD Ezzahar J. auteur aut IRD Fruneau B. auteur aut IRD Rudant J. P. auteur aut IRD Lionel J. auteur aut IRD text journalArticle eng text/pdf reformatted digital access This article aimed to monitor vegetation using C-band radar data at a subdaily time step. To this end, radar measurements using tower-mounted antennas with a 15-min time step, along with physiology-related information (sapflow and micrometric dendrometry), were acquired quasi-continuously from March 2020 to December 2021 in an olive orchard located near Marrakech, Morocco. The article focused on temporal coherence, whose clear diurnal cycle (highest at night and lowest at the end of the afternoon) had been highlighted over tropical and boreal forests in previous studies. The results showed that coherence was highly sensitive to: wind-induced movement of scatterers, since coherence was lowest when wind speed was highest in late afternoon, and vegetation activity, especially its water dynamics, since the morning coherence drop coincided with the onset of sapflow and the daily evapotranspiration cycle, as well as the good agreement between the temporal drop rate of coherence and the daily residual variation in trunk circumference (i.e., deviation from long-term trend). Finally, coherence remained high for temporal baselines of several days, showing that sentinel-1 data (when both satellites are operational) may be well suited for such studies, especially with acquisitions made during morning passes, when wind speed is low. These results open perspectives for monitoring tree crop physiology using high-revisit-time radar observations. specialized Radar Coherence Radar antennas Temperature measurement C-band Irrigation Antennas C-band olive orchard radar temporal coherence water status MAROC ZONE SEMIARIDE 126 072 17 3635-3647 2024 1939-1404 https://www.documentation.ird.fr/hor/fdi:010089700 10.1109/jstars.2024.3352699 1939-1404 [F B010089700] https://www.documentation.ird.fr/hor/fdi:010089700 https://horizon.documentation.ird.fr/exl-doc/pleins_textes/2024-05/010089700.pdf IRD - Base Horizon / Pleins textes 2024-05-22 2025-11-06 fdi:010089700 fre