WF-7 · Etna Forecast — probabilistic nowcasting

Etna Forecast — probabilistic nowcasting

Educational 24-hour and 5-day probabilities from public multimodal data, with baselines, a modality gate and calibration scorecard.

Active · educationalMonday, Thursday, Sunday and eventsGeoscience · AI/ML · nowcasting
Educational card with 24-hour and 5-day eruption probabilities.
1 · In one sentence

Educational probabilistic nowcasting at 24 hours and 5 days, built from public multimodal data and allowed to degrade to declared baselines.

2 · Why it exists

To measure honestly whether seismic, thermal and tremor data add value over event history, without imitating an official forecast.

3 · What it produces

Current probabilities and a separate model-metrics card.

The first image shows 24-hour and 5-day horizons, the selected source and degraded modalities. The second exposes Brier score, baselines, candidate models and the matured track record.

A lower Brier score means probabilities are better calibrated on average.

4 · How it works

From geophysical data to the selected probability.

Etna probabilistic nowcasting pipeline diagram
Point-in-time features, models and baselines, purged validation and modality gate.
2Multimodal features
3Baselines
4ML models
5Gate
6Scorecard

5 · Data used

Modalities and controls
SourceInformationMain featuresControl
INGV VONA / episodesevent historydays since episode, 30/90-day counts, Hawkeslabel audit and immutable records
FDSNseismicity and tremorcounts by radius, Benioff, depth, RMS, slope, entropy, Hurstpoint-in-time cutoff and valid hours
NASA FIRMSthermal anomaliesFRP, counts, slope and days since hotspotcloud censoring and NaN beyond coverage
Open-Meteocloud covervalid days and censored ratioobserved zero separated from missing
6 · Feature engineering

Physical signals, complexity and regime

Aki–Utsu b-value, depth migration, Benioff strain, regional stress, FRP per clear day, permutation entropy, Hurst-DFA, HF/VT ratio and episode-regime features.

7 · Models and gate

ML against strong baselines

Calibrated elastic net and LightGBM by modality and combination; climatology, persistence and Hawkes process as baselines. The modality gate selects the best-calibrated source by fold and declares fallback use.

Current evidence: event history/Hawkes is still frequently selected. The incremental value of seismic, thermal and tremor modalities has yet to prove stable out of sequence; the workflow publishes this negative result rather than hiding it.

9 · Limits

Educational, not operational

Public data may be incomplete or delayed and the positive sample is limited. This is not an INGV bulletin and must not be used for safety or civil-protection decisions.

Possible applications of the pattern

Multimodal nowcasting with fallback and scorecard.

The pattern can support rare-event research when modality availability changes and a strong baseline must remain competitive and visible.

Research questions

  • real incremental value of modalities
  • rare-event calibration
  • episode-level stability
  • drift and source completeness

Workflow technical dossier

IMPLEMENTEDDescribes repository behaviour.PROVISIONALScientific skill remains dependent on data completion and matured sample size.

Probabilistic AI/ML, data engineering and MLOps.

The repository prioritises temporal correctness, baselines, calibration and failure modes over complexity for its own sake.

Architecture and data

  • Full historical backfill separated from cache-aware incremental updates.
  • Feature tables in Parquet/Pickle, versioned forecast records and an HTML dashboard.
  • HTTP acquisition, HTML/PDF parsing and FDSN; cache saved even after degraded runs.

Features and models

  • 1/3/7/14/30-day windows, geographic distances and coverage features.
  • LightGBM/scikit-learn, calibrated candidates and Hawkes baseline.
  • Blend and per-horizon gate with documented source choice.

Validation and governance

  • Purged walk-forward, embargo and holdout; Brier score and matured live scorecard.
  • Offline synthetic self-test, pytest, Ruff, workflow YAML and cold-cache runtime test.
  • Educational disclosure, INGV as authoritative source and independent bilingual posts.

Stack

  • pandas, NumPy, SciPy, PyArrow, scikit-learn and LightGBM.
  • requests, Beautiful Soup, pypdf and optional ObsPy for tremor.
  • Pillow, HTML/CSS, GitHub Actions and AT Protocol.

10 · Runtime

Scheduled runs and event-time activation.

  • Status: active · educational · declared degradation
  • Frequency: Monday, Thursday and Sunday; additional event runs
  • Output: probability card, metrics and dashboard

11 · Technical detail

How is the Brier score calculated?

For each probability forecast p and observed outcome y ∈ {0,1}, the contribution is (p − y)²; the Brier score is the mean over matured cases. Lower is better. Brier Skill Score compares the model with a baseline: BSS = 1 − BS_model / BS_baseline; it is positive only when the model truly improves on that baseline.

Why use Hawkes?

It models temporal self-excitation and provides a strong baseline: the multimodal model must demonstrate incremental value out of sequence.

What is the modality gate?

It compares candidate sources across folds and selects the best-calibrated one, including a baseline when modalities add no value or are incomplete.

Main failure mode

Treating an educational probability as an alert, or confusing good calibration with event certainty.

See probabilities and metrics in the same post.

The Publications gallery lets readers move between the two localised images.

Open publications