Remote sensing-based evapotranspiration (ET) models with various levels of sophistication have emerged recently with the possibilities of user-defined model calibrations. Their application for water resources management and climate studies from regional to global scale has been rapidly increasing, which makes it important to validate field scale ET in a complex crop assemblage before operational use. Based on in situ flux-tower measurements by the eddy-covariance (EC) system, this study tested three single-source energy balance models for estimating daily ET from fennel/maize/ryegrass-clover cropland rotations in a Mediterranean context in southern Italy. The sensitivity of three user-friendly ET models (SEBS, QWaterModel, and METRIC-EEFlux) with reference to the EC system over a center pivot irrigated cropland is discussed in detail. Results in terms of statistical indicators revealed that SEBS and METRIC-EEFlux showed reasonable agreements with measured ET (r² = 0.59_SEBS, RMSE = 0.71 mm day⁻¹; r² = 0.65_METRIC, RMSE = 1.13 mm day⁻¹) in terms of trends and magnitudes. At 30 m spatial resolution, both models were able to capture the in-field variations only during the maize development stage. The presence of spurious scan lines due to sensor defects in Landsat L7 ETM+ can contribute to the qualities of the METRIC-Efflux’s ET product. In our observation, the QWaterModel did not perform well and showed the weakest congruency (r² = 0.08_QWaterModel) with ground-based ET estimates. In a nutshell, the study evaluated these automated remote sensing-based ET estimations and suggested improvements in the context of a generic approach used in their underlying algorithm for robust ET retrievals in rotational cropland ecosystems.

The heterogeneous ecosystems in the Mediterranean Basin (MB) are becoming sensitive to water stress. To investigate the climatic stress, a water budget study was conducted over the basin using TerraClimate simulations for a long temporal range (1990–2020). According to the budget accounting, forested regions received the highest precipitation (P) on average compared to other land use types (annual mean ≈633 mm yr⁻¹), and even then, they were in a water deficit state (−0.42 mm yr⁻¹). Tree plantations in North Africa (Libya and Morocco) were also in a water deficit state; however, their average P was very low (≈12 mm yr⁻¹) compared to that of northern parts of the MB, and the average Actual Evapotranspiration (AET) was ≈15 mm yr⁻¹. Also, the water balance in other land use systems (rain-fed, irrigated croplands, and rangelands) was either negative or near zero. As a whole, the basin’s average annual P was ≈538 mm yr⁻¹, the annual average AET was ≈415 mm yr⁻¹, and the runoff (Q) was equivalent to 123 mm yr⁻¹, which shows a strong influence of ET over the region. Since runoff was negligible in most dry areas, the AET’s large contribution was notable in the North African base of the Atlas Mountains including the Nile delta region. This indicates that precipitation and evaporation are the principal mechanisms of the water balance in the MB. The result shows strong climate variability over Southern Europe, Turkey, and the western Balkans in the recent years, affecting the AET and making their land use systems more vulnerable to water stress. This benchmark study signifies the consistent need for water storage in the Mediterranean vegetation systems of the basin. It also indicates two distinct climate clusters for water balance modeling.

Agriculture and agri-food systems of the highly vulnerable Middle East and North Africa (MENA) region needs a radical transformation under a changing climate. Based on a two-year effort, initially we developed a mega hypothesis on how to achieve climate-smart agri-food transformation in the region. In the study, we hypothesized that “Climate-Smart Lifts” implemented in the enabling environments can rapidly facilitate agri-food transformation in the region. In order to gather the stakeholders’ perception about this, we organized a collective conversation among ~400 stakeholders that represent various scales and sectors within the agriculture sector in MENA. These “listening cum learning consultations” were conducted through a survey followed by a series of webinars. The webinar discussions were strategically guided based on our hypothesis, the responses from the surveys and the regional needs. These discussions provided a forum to bring-out the stakeholders’ perspective on what new knowledge, partnerships, instruments and projects were needed in the MENA. The deliberation focused on the opportunities of public–private partnerships focusing in all the four major agroecosystems in MENA (irrigated, rainfed, rangelands, and deserts). In result, we developed an effective framework for strategic resource mobilization in the region, keeping in view the strong regional needs for climate actions and the requisite long-term commitments for the SDGs implementation.

Accurate evapotranspiration (ET) estimation is crucial for sustainable water management in the diverse and water-scarce Mediterranean region. This study compares three prominent models (Simulator of Terrestrial Ecohydrological Processes and Systems (STEPS), Soil-Canopy-Observation of Photosynthesis and Energy fluxes (SCOPE), and Two-Source Energy Balance (TSEB)) with established global datasets (Moderate Resolution Imaging Spectroradiometer 8-day global terrestrial product (MOD16A2), Global Land Evaporation Amsterdam Model (GLEAM), and TerraClimate) at multiple spatial and temporal scales and validates model outcomes with eddy covariance based ground measurements. Insufficient ground-based observations limit comprehensive model validation in the eastern Mediterranean part (Turkey and Balkans). The results reveal significant discrepancies among models and datasets, highlighting the challenges of capturing ET variability in this complex region. Differences are attributed to variations in ecosystem type, energy balance calculations, and water availability constraints. Ground validation shows that STEPS performs well in some French and Italian forests and crops sites but struggles with seasonal ET patterns in some locations. SCOPE mostly overestimates ET due to detailed radiation flux calculations and lacks accurate water limitation representation. TSEB faces challenges in capturing ET variations across different ecosystems at a coarser 10 km resolution. No single model and global dataset accurately represent ET across the entire region. Model performance varies by region and ecosystem. As GLEAM and TSEB excel in semi-arid Savannahs, STEPS and SCOPE are better in grasslands, croplands, and forests in few locations (5 out of 18 sites) which indicates these models need calibration for other locations and ecosystem types. Thus, a region-specific model calibration and validation, sensitive to extremely humid and arid conditions can improve ET estimation across the diverse Mediterranean region.