The opening and closing of plant stomata regulates the global water, carbon and energy cycles. Biophysical feedbacks on climate are highly dependent on transpiration, which is mediated by vegetation phenology and plant responses to stress conditions. Here, we explore the potential of satellite observations of solar-induced chlorophyll fluorescence (SIF)\uffe2\uff80\uff94normalized by photosynthetically-active radiation (PAR)\uffe2\uff80\uff94to diagnose the ratio of transpiration to potential evaporation (\uffe2\uff80\uff98transpiration efficiency\uffe2\uff80\uff99, \uffcf\uff84). This potential is validated at 25 eddy-covariance sites from seven biomes worldwide. The skill of the state-of-the-art land surface models (LSMs) from the eartH2Observe project to estimate \uffcf\uff84 is also contrasted against eddy-covariance data. Despite its relatively coarse (0.5\uffc2\uffb0) resolution, SIF/PAR estimates, based on data from the Global Ozone Monitoring Experiment 2 (GOME-2) and the Clouds and Earth\uffe2\uff80\uff99s Radiant Energy System (CERES), correlate to the in situ \uffcf\uff84 significantly (average inter-site correlation of 0.59), with higher correlations during growing seasons (0.64) compared to decaying periods (0.53). In addition, the skill to diagnose the variability of in situ \uffcf\uff84 demonstrated by all LSMs is on average lower, indicating the potential of SIF data to constrain the formulations of transpiration in global models via, e.g., data assimilation. Overall, SIF/PAR estimates successfully capture the effect of phenological changes and environmental stress on natural ecosystem transpiration, adequately reflecting the timing of this variability without complex parameterizations.
", "keywords": ["VEGETATION DYNAMICS", "Science", "STOMATAL CONDUCTANCE", "0207 environmental engineering", "solar-induced chlorophyll fluorescence", "02 engineering and technology", "01 natural sciences", "transpiration", "CARBON", "GOME-2", "WATER", "PLANT", "0105 earth and related environmental sciences", "EVAPOTRANSPIRATION", "Q", "Biology and Life Sciences", "15. Life on land", "MODEL", "EVAPORATION", "SOIL", "PARTITIONING", "transpiration efficiency", "efficiency", "13. Climate action", "Earth and Environmental Sciences", "INDUCED CHLOROPHYLL FLUORESCENCE", "solar-induced chlorophyll fluorescence; transpiration; transpiration efficiency; GOME-2; eddy-covariance", "eddy-covariance"]}, "links": [{"href": "http://www.mdpi.com/2072-4292/11/4/413/pdf"}, {"href": "https://doi.org/10.3390/rs11040413"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Remote%20Sensing", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.3390/rs11040413", "name": "item", "description": "10.3390/rs11040413", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.3390/rs11040413"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2019-02-18T00:00:00Z"}}, {"id": "10.1098/rstb.2017.0302", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-30T16:19:07Z", "type": "Journal Article", "created": "2018-10-08", "title": "Tropical land carbon cycle responses to 2015/16 El Ni\u00f1o as recorded by atmospheric greenhouse gas and remote sensing data", "description": "The outstanding tropical land climate characteristic over the past decades is rapid warming, with no significant large-scale precipitation trends. This warming is expected to continue but the effects on tropical vegetation are unknown. El Ni\uffc3\uffb1o-related heat peaks may provide a test bed for a future hotter world. Here we analyse tropical land carbon cycle responses to the 2015/16 El Ni\uffc3\uffb1o heat and drought anomalies using an atmospheric transport inversion. Based on the global atmospheric CO 2 and fossil fuel emission records, we find no obvious signs of anomalously large carbon release compared with earlier El Ni\uffc3\uffb1o events, suggesting resilience of tropical vegetation. We find roughly equal net carbon release anomalies from Amazonia and tropical Africa, approximately 0.5 PgC each, and smaller carbon release anomalies from tropical East Asia and southern Africa. Atmospheric CO anomalies reveal substantial fire carbon release from tropical East Asia peaking in October 2015 while fires contribute only a minor amount to the Amazonian carbon flux anomaly. Anomalously large Amazonian carbon flux release is consistent with downregulation of primary productivity during peak negative near-surface water anomaly (October 2015 to March 2016) as diagnosed by solar-induced fluorescence. Finally, we find an unexpected anomalous positive flux to the atmosphere from tropical Africa early in 2016, coincident with substantial CO release.
This article is part of a discussion meeting issue \uffe2\uff80\uff98The impact of the 2015/2016 El Ni\uffc3\uffb1o on the terrestrial tropical carbon cycle: patterns, mechanisms and implications\uffe2\uff80\uff99.
", "keywords": ["Life Sciences & Biomedicine - Other Topics", "FLUX", "0301 basic medicine", "Hot Temperature", "550", "551", "global warming", "01 natural sciences", "Carbon Cycle", "Greenhouse Gases", "03 medical and health sciences", "[SDU.STU.CL] Sciences of the Universe [physics]/Earth Sciences/Climatology", "CHEMICAL-TRANSPORT MODEL", "carbon cycle", "INVERSION", "Biology", "TEMPERATURE", "11 Medical and Health Sciences", "0105 earth and related environmental sciences", "tropical forests", "El Nino-Southern Oscillation", "Evolutionary Biology", "Tropical Climate", "Science & Technology", "Atmosphere", "PHOTOSYNTHESIS", "EQUATORIAL PACIFIC", "Articles", "06 Biological Sciences", "15. Life on land", "[SDU.ENVI] Sciences of the Universe [physics]/Continental interfaces", " environment", "6. Clean water", "Droughts", "[SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology", "13. Climate action", "PRECIPITATION", "Remote Sensing Technology", "INDUCED CHLOROPHYLL FLUORESCENCE", "CO2", "[SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces", "SENSITIVITY", "environment", "Life Sciences & Biomedicine", "fire"]}, "links": [{"href": "https://eprints.whiterose.ac.uk/135234/8/Tropical%20land%20carbon%20cycle%20responses%20to%202015/16%20El%20Ni%C3%B1o%20as%20recorded%20by%20atmospheric%20greenhouse%20gas%20and%20remote%20sensing%20data.pdf"}, {"href": "https://royalsocietypublishing.org/doi/pdf/10.1098/rstb.2017.0302"}, {"href": "https://doi.org/10.1098/rstb.2017.0302"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Philosophical%20Transactions%20of%20the%20Royal%20Society%20B%3A%20Biological%20Sciences", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1098/rstb.2017.0302", "name": "item", "description": "10.1098/rstb.2017.0302", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1098/rstb.2017.0302"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2018-10-08T00:00:00Z"}}], "links": [{"rel": "self", "type": "application/geo+json", "title": "This document as GeoJSON", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=INDUCED+CHLOROPHYLL+FLUORESCENCE&f=json", "hreflang": "en-US"}, {"rel": "alternate", "type": "text/html", "title": "This document as HTML", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=INDUCED+CHLOROPHYLL+FLUORESCENCE&f=html", "hreflang": "en-US"}, {"rel": "collection", "type": "application/json", "title": "Collection URL", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main", "hreflang": "en-US"}, {"type": "application/geo+json", "rel": "first", "title": "items (first)", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=INDUCED+CHLOROPHYLL+FLUORESCENCE&", "hreflang": "en-US"}, {"rel": "last", "type": "application/geo+json", "title": "items (last)", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=INDUCED+CHLOROPHYLL+FLUORESCENCE&offset=2", "hreflang": "en-US"}], "numberMatched": 2, "numberReturned": 2, "distributedFeatures": [], "timeStamp": "2026-05-31T03:13:25.317939Z"}