# Remote Sensing for Irrigation of Horticultural Crops
## 3 Sensors and Platforms
### Remote Sensing Platforms
#### 3.2.1 Satellite
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**Satellite** & **Resolution** & **Revisit (Days)** & **Instruments** & **Field of Application** \\ \hline Worldwide-1 & 0.46 m & 1.7 & Panchromatic & Provides highly detailed imagery for precise map creation, change detection, and in-depth image analysis \\ \hline \multirow{6}{*}{Worldwide-2} & \multirow{6}{*}{0.46 m} & \multirow{6}{*}{1.1} & High-resolution panchromatic band and eight multispectral bands; four standard colors (red, & It collects very large areas of multispectral imagery in a single pass. It performs precise and four new bands (sonal, & change detection and mapping. \\  & & & yellow, red edge, & near-infrared (2). \\ \hline \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \multicolumn{5}{c}{} \\ \end{tabular}
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Table 1: _Cont._the object-based approach were not extremely high. The authors relied on the support of two twin S2 satellites for consistently improving spectral and temporal information with high spatial resolution. [PERSON] et al. [66] have conducted an experiment on regional evapotranspiration and crop water consumption estimated over an irrigated area in Tunisia with the SAMIR model that used SPOT high-resolution time series. The SAMIR model was calibrated with local evapotranspiration measurements taken from flux towers. It was validated at plot and perimeter scales using known irrigation volumes. The objective of the work was to assess the operational feasibility and accuracy of SAMIR outputs at plot and perimeter scales, in a context of high land cover complexity (i.e., trees, winter cereals, summer vegetables) and limited data available for parameterization. The authors concluded that acquisition frequency (five days) of the satellite Sentinel-2 would not answer the problem of cloudiness, even in semi-arid conditions, as in the case of Tunisia. The authors suggested the combination with Landsat8 or SPOT, which have VIS-NIR high-resolution sensors. Using these time series, including clear images approximately every 20 days, would make it possible to estimate irrigation volumes at perimeters scale. The seasonal volumes estimated by this method appeared acceptable, even though results at finer timescales (monthly and below) need to be improved. A variety of variables (e.g., leaf chlorophyll content, leaf water content, leaf area index) are proposed for Sentinel-2 as inputs to earth system models. [PERSON] and [PERSON] [63] summarized spectral position (\(\lambda\)) and bandwidth (\(\Delta\lambda\)), spatial resolution, heritage and purpose of Sentinel-2 bands, according to the Copernicus derived user requirements. [PERSON] and [PERSON] [67] reported recently on soil moisture measurements by remote sensing at local and regional scales. Recent technical developments have allowed the outgrowth of space borne L-band microwave radiometry. Two satellite missions, the Soil Moisture and Ocean Salinity (SMOS, 2009) and the Soil Moisture Active Passive (SMAP, 2015) provide global mapping of surface soil moisture based on radiometric measurements at L-band (21 cm, 1.4 GHz). The authors found SMOS to be the only satellite able to detect irrigation and the only one that does not show clear vegetation or roughness effects and is able to map irrigated areas. [PERSON] et al.