Project aim

Test whether an Earth observation foundation model produces better 10 m crop-type maps for Ghanaian smallholder landscapes than a conventional CNN baseline, without leaking spatial information between training and test data.

  • >0.70F1 (spatial CV)
  • 10 mMap resolution
  • ClayFoundation model
  • ResNet-50Baseline
Illustrative map for Crop-Type Mapping with EO Foundation Models Illustrative graphic

Overview

The project fine-tunes the Clay foundation model on multi-temporal Sentinel-2 stacks over Ejura and benchmarks it against a ResNet-50 baseline. Evaluation uses spatial cross-validation across agro-ecological zones, and the fine-tuned model reaches an F1 score above 0.70.

The challenge

Smallholder fields are small, irregular and often intercropped, and labelled data is scarce. Random train/test splits overstate accuracy because neighbouring pixels are nearly identical, so the evaluation has to hold out whole regions to mean anything.

Data & inputs

  • Sentinel-2 multi-temporal stacks
  • Crop-type labels
  • Agro-ecological zones

Approach

  1. 01

    Multi-temporal stacks

    Sentinel-2 imagery is assembled into multi-temporal stacks covering the growing season.

  2. 02

    Foundation-model fine-tuning

    The Clay EO foundation model is fine-tuned for 10 m crop-type classification.

  3. 03

    Baseline

    A ResNet-50 is trained on the same data as a conventional point of comparison.

  4. 04

    Spatial cross-validation

    Folds are split by agro-ecological zone so test areas are never adjacent to training areas.

Results

Under spatial cross-validation across agro-ecological zones, the fine-tuned model achieves an F1 score above 0.70.

Validation

Spatial cross-validation across agro-ecological zones, benchmarked against a ResNet-50 baseline.