Accurate　characterization　of　spatial　patterns　and　temporal　variations　in　dryland　vegetation　is　of　great　importance　for　improving　our　understanding　of　terrestrial　ecosystem　functioning　under　changing　climates.　Here,　we　explored　the　spatiotemporal　variability　of　dryland　vegetation　phenology　using　satellite-observed　Solar-Induced　chlorophyll　Fluorescence　(SIF)　and　the　Enhanced　Vegetation　Index　(EVI)　along　the　North　Australian　Tropical　Transect　(NATT).　Substantial　impacts　of　extreme　drought　and　intense　wetness　on　the　phenology　and　productivity　of　dryland　vegetation　are　observed　by　both　SIF　and　EVI,　especially　in　the　arid/semiarid　interior　of　Australia　without　detectable　seasonality　in　the　dry　year　of　2018-2019.　The　greenness-based　vegetation　index　(EVI)　can　more　accurately　capture　the　seasonal　and　interannual　variation　in　vegetation　production　than　SIF　(EVI　r(2):　0.47　similar　to　0.86,　SIF　r(2):　0.47　similar　to　0.78).　However,　during　the　brown-down　periods,　the　rate　of　decline　in　EVI　is　evidently　slower　than　that　in　SIF　and　in　situ　measurement　of　gross　primary　productivity　(GPP),　due　partially　to　the　advanced　seasonality　of　absorbed　photosynthetically　active　radiation.　Over　70%　of　the　variability　of　EVI　(except　for　Hummock　grasslands)　and　40%　of　the　variability　of　SIF　(except　for　shrublands)　can　be　explained　by　the　water-related　drivers　(rainfall　and　soil　moisture).　By　contrast,　air　temperature　contributed　to　25　similar　to　40%　of　the　variability　of　the　effective　fluorescence　yield　(SIFyield)　across　all　biomes.　In　spite　of　high　retrieval　noises　and　variable　accuracy　in　phenological　metrics　(MAE:　8　similar　to　60　days),　spaceborne　SIF　observations,　offsetting　the　drawbacks　of　greenness-based　phenology　products　with　a　potentially　lagged　end　of　the　season,　have　the　promising　capability　of　mapping　and　characterizing　the　spatiotemporal　dynamics　of　dryland　vegetation　phenology.