Drought-Impact Prediction Benchmark (v0): county-level insured drought loss for corn and soybean in the US Corn Belt

A prediction-ready, impact-labeled drought benchmark: predict realized insured drought loss (USDA RMA Cause of Loss) from within-season climate/vegetation anomalies. v0 covers corn and soybean across the 6-state US Corn Belt (IL/IN/IA/MN/MO/NE), 2000-2023 (13,895 county-years and 587 counties per crop; positive rate 6.0% for corn, 4.8% for soybean). The drought-loss ratio uses the true total insured liability from the RMA Summary-of-Business coverage files (removing the loss-experience >1 artifact). Distinct from drought-severity (USDM) and crop-yield benchmarks. Includes official temporal / leave-one-state-out spatial / leave-one-year-out splits and a baseline leaderboard (best temporal ROC-AUC 0.95 for corn and 0.93 for soybean; spatial leave-one-state-out 0.91 for corn and 0.90 for soybean). Built and reproducible with the open-source terraflow.drought pipeline; each build carries a deterministic SHA-256 fingerprint in manifest.json.