Evapotranspiration Mapping and Crop Analysis in Hemavathy Command Area

1. INTRODUCTION This project aims to analyze the spatial and temporal variation of evapotranspiration (ET) and crop patterns within the Hemavathy Left Bank Canal Command area, Karnataka. The study focuses on understanding seasonal water demand and its variation over multiple years, along with assessing the influence of climate variability on crop water requirements. 2. OBJECTIVES * To generate seasonal evapotranspiration maps for multiple years * To classify crop patterns using satellite imagery * To estimate crop water requirements spatially * To analyze temporal variation in ET and relate it to climate variability 3. STUDY AREA Hemavathy Left Bank Canal Command, Karnataka, India (AOI shapefile will be provided) 4. METHODOLOGY 4.1 Reference Evapotranspiration (ET₀) Computed using FAO-56 Penman-Monteith method based on weather data (temperature, humidity, wind speed, solar radiation). 4.2 Actual Evapotranspiration (ETa) Estimated using SEBAL (Surface Energy Balance Algorithm for Land) based on satellite data (Landsat/Sentinel with thermal bands). 4.3 Temporal Analysis Years considered: 2016, 2018, 2020, 2022, 2024, 2025 For each year: * Wet season (Kharif) ET map * Dry season (Rabi/Summer) ET map Total outputs: * 12 ET₀ maps * 12 ETa maps 4.4 Crop Classification * Satellite-based classification using Sentinel-2 / Landsat time-series * NDVI or supervised classification approach * Identification of actual crops present in the AOI 4.5 Climate Variability Analysis * Analysis of temperature and rainfall trends * Correlation with ET variation across years * Basic interpretation of impact on crop water demand 5. DATA REQUIREMENTS * AOI boundary (to be provided) * Weather data (provided or sourced from NASA POWER / ERA5) * Satellite imagery (Sentinel-2, Landsat) 6. DELIVERABLES * 12 ET₀ seasonal maps (GeoTIFF) * 12 ETa (SEBAL-based) seasonal maps (GeoTIFF) * Crop classification map * Climate variability analysis (maps + brief report) * Metadata file (CRS, resolution, data sources, workflow) * Google Earth Engine code (preferred) 7. VALIDATION * Accuracy assessment for crop classification (confusion matrix or equivalent) * Logical validation of ET outputs 8. TECHNICAL REQUIREMENTS * Use of Google Earth Engine for processing * Final outputs compatible with QGIS/ArcGIS * Consistent spatial resolution and projection across all outputs 9. TIMELINE Expected completion: 3 - 4 days 10. EXPECTATIONS * Clear methodology * Scientifically accurate outputs * No assumptions without justification * Clean and usable GIS-ready datasets Please provide: * Relevant experience (especially SEBAL implementation) * Tools and workflow you will use * Total fixed cost (no additional charges)

Project ID: 40420512