markfriedlander/wsl-analyzer

WSL Championship Tour Heat-Level Dataset (2014–2025)

A complete, structured, hash-chained dataset of every World Surf League Men's and Women's Championship Tour heat from 2014 through 2025 — 230 events, 7,494 heats, 17,710 surfer-heat rows, 103,489 individual waves — joined to break geometry and ERA5 oceanic/atmospheric reanalysis.

Built for fantasy-league optimization, surf analytics, and educational machine-learning work. Every row is identified by a deterministic SHA-256 hash chain, every value is sourced from the public WSL website with documented provenance, and every known source-data limitation is recorded explicitly rather than papered over.

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Quick start

import sqlite3
import pandas as pd

conn = sqlite3.connect("wsl-v4.sqlite")

# All heats from a recent event with conditions
heats = pd.read_sql("""
    SELECT e.name, h.heat_date, h.wave_range, h.wind_condition,
           era5.wave_height_m, era5.wind_speed_kmh
    FROM Event e
    JOIN Heat h ON h.event_id = e.event_id
    LEFT JOIN ERA5Conditions era5
      ON era5.break_id = h.break_id
     AND DATE(era5.observation_hour) = h.heat_date
     AND CAST(substr(era5.observation_hour, 12, 2) AS INTEGER) = 12  -- noon
    WHERE e.year = 2025 AND e.tour = 'MCT'
""", conn)

For a working schema dump, run sqlite3 wsl-v4.sqlite '.schema' after download.

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Dataset summary

• Coverage: 2014–2025, both Men's CT (MCT) and Women's CT (WCT), all events including wave-pool stops (Surf Ranch, Freshwater Pro, Surf Abu Dhabi, Jeep Surf Ranch).
• Granularity: Wave-level. Every wave a surfer caught in every heat is a row, with score, counted/uncounted flag, interference flag, and direction (for wave-pool events).
• Format: Single SQLite file (~18 MB, 9 tables, 7 indexes). The compact size is deliberate — see "ERA5 design choice" below.
• Identity: Every primary key is a deterministic SHA-256 hash truncated to 16 hex characters. The hash chain encodes ancestry: wave_id = SHA256(heat_id|athlete_id|wave_index), heat_id = SHA256(round_id|heat_number), etc. Two independent observers computing IDs from the same source HTML produce the same IDs — the dataset is reproducible by construction.
• Conditions: ERA5 reanalysis from Open-Meteo (Marine + Archive APIs) joined by (break_id, observation_hour). 98.5% of heats join to a full 24-hour ERA5 day at their break.
• Audit: Verdict HEALTHY, 0 Critical, 0 Major findings. 365 / 365 stratified-sample heats verified clean against the live WSL site at publication time.

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Tables

Table	Rows	Purpose
Event	230	One row per (year, tour, name, location, anomaly_class). MCT and WCT are always separate rows.
Round	1,496	Three columns: round_id, event_id, round_number. No display name (app-layer concern).
Heat	7,494	The principal competitive unit. Date, duration, conditions, break, wsl_heat_id for source traceability.
HeatSurfer	17,710	(heat × surfer) pairing with total_score and outcome_type.
Wave	103,489	One row per wave. Score, is_counted (top-2-counted indicator), is_zeroed_by_interference, direction (wave-pool only).
Surfer	474	Surfer profile: nationality, stance, DOB, height/weight (where WSL publishes them).
Break	40	Geographic + competitive metadata — lat/lon, break type/handedness, swell window, orientation.
BreakAlias	196	Year-aware mapping of WSL-rendered location strings → canonical break_id.
ERA5Conditions	15,264	Hourly ERA5 reanalysis: wave height/period/direction, wind speed/direction, surface pressure.

Hash chain (governing identity rule)

event_id     = SHA256(name | year | tour | location | x)[:16]
round_id     = SHA256(event_id | round_number)[:16]
heat_id      = SHA256(round_id | heat_number)[:16]
heatentry_id = SHA256(heat_id | athlete_id)[:16]
wave_id      = SHA256(heat_id | athlete_id | wave_index)[:16]
break_id     = SHA256(name | lat:.6f | lon:.6f)[:16]
condition_id = SHA256(break_id | observation_hour)[:16]
athlete_id   = SHA256(name | date_of_birth | nationality)[:16]

x = 1 for multi-break events (heats span breaks with different competitive character — e.g. 2018 Margaret River split across North Point, Margaret River, Uluwatu after a shark incident; 2020 Maui Pro split between Honolua Bay and Pipeline). Heat-level break_id is authoritative for which specific break each heat ran at.

NULL sentinel: any field that is NULL in the source uses the literal string "NULL" in hash inputs. Exception: heat_number falls back to 1-based positional ordering within its round when the source HTML doesn't provide a number, to avoid hash collisions.

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Coverage by year and tour

Year	MCT events	WCT events	Notes
2014–2019	11	10	Standard tour
2020	1	1	COVID-disrupted year. Only the December 2020 Pipe Masters and Maui Pro made it.
2021	7	7	Truncated COVID-recovery season
2022–2024	10–11	10–11	Standard tour
2025	12	12	Current full season (latest)

Pre-2014 data is not included in this release. Earlier development generations of this dataset once contained partial MCT 2008–2013 and WCT 2010–2013 data scraped from WSL's archive, but per-wave detail is incomplete for that era and those generations were superseded before v4. The current production database and the available pre-v4 backup both cover 2014 onward only. v4 is therefore not a 2008-onward archive with the early years stripped — it is a uniform 2014–2025 dataset by design, where every event has full wave-level fidelity.

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Data sources and provenance

Competition data is scraped from public WSL results pages (worldsurfleague.com/events/...) using the heat-popup endpoint and round-listing pages. Every heat record is traceable back to a specific WSL URL via Heat.wsl_heat_id. Recent re-crawls (April 2026) used direct popup-by-popup parsing with grid-attribution validation; earlier crawl batches were verified end-to-end against the same source.

ERA5 conditions come from Open-Meteo's Marine API (models=era5_ocean) and Archive API (models=era5). Hourly resolution, 0.25–0.5° spatial. Stored as raw values — no aggregation at the storage layer.

ERA5 design choice — why the dataset is ~18 MB. A naïve enrichment fetches ERA5 for every hour of every day across each break's full historical span. For 28 ocean breaks over a 12-year window that's ~2.9 million hourly rows, the vast majority of which would never join to a heat (heats happen on a handful of discrete days per year, not continuously). The v3 predecessor of this dataset stored ~129 MB primarily for that reason. v4 instead fetches ERA5 only for the actual heat days each break sees — one 24-hour ERA5 day per unique (break_id, heat_date) pair — producing 15,336 rows with 100% ocean-heat join coverage. Same usability, ~7× smaller file. Wave-pool venues (Surf Ranch, Surf Abu Dhabi) carry zero ERA5 rows by policy: pool conditions are mechanically generated and are not derivable from offshore reanalysis, so populating them would create joinable but physically meaningless values.

Surfer profile data (nationality, stance, DOB, height/weight) is scraped from individual athlete profile pages. Nationality follows WSL's competitive designation rather than legal citizenship (e.g. Hawaiian surfers are listed as "Hawaii", not "United States" — WSL treats Hawaii as a separate competitive territory).

No carry-forward. Every row of competition data was fetched fresh from WSL's current servers in 2026, parsed by an audited parser, and validated against per-heat consistency rules (e.g. total_score == sum(top-2 counted scores) for every surfer). Six events that were originally carried forward from a prior release were purged and re-crawled in this release.

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Verification status

• Audit verdict: HEALTHY (0 Critical, 0 Major, 14 Minor, 36 Info findings).
• Stratified sample verifier: 365 / 365 heats verified clean. Sample stratifies by year (≥15 ocean heats per year) and per wave-pool event (≥3 heats per event, or all heats for events with fewer than 3 by structure).
• Per-heat consistency: Every HeatSurfer.total_score reconciles with SUM of the top-2 counted Wave scores within the same (heat, athlete) within ±0.011 tolerance, except where WSL applied an interference penalty.
• Hash-chain integrity: Every Wave traces to a HeatSurfer traces to a Heat traces to a Round traces to an Event; no orphan rows.

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Known limitations (documented)

1. Heat times not stored. Granularity is day-only (heat_date). WSL does not publish per-heat start times for historical heats. ERA5 joins use day-level matching and let the consumer decide which hour(s) to interpolate.

2. Penalty 1 (interference halving) not detectable. WSL applies interference at three tiers: (1) second-best wave halved, (2) second-best wave zeroed, (3) best wave zeroed. Tiers 2 and 3 are captured via Wave.is_zeroed_by_interference = 1 (cell carries wave--adjusted class AND score = 0.0). Tier 1 is a score reduction with no machine-readable HTML signal — the pre-halving score is never published. The post-halving score (which we store) is correct as a score; only the "this was halved" annotation is missing. No re-crawl will fix this — it's a source-data limitation.

3. TBD waves. WSL renders some wave-grid cells as the literal text "TBD" — slots that exist on the wave grid but never received a numeric score (likely WSL data-entry gaps). v4 stores TBD waves as Wave rows with score = NULL, is_counted = 0. The wave_count column matches WSL's display; aggregations should filter WHERE score IS NOT NULL to exclude. There are 12 TBD waves total.

4. Heat.wsl_heat_id = -1 sentinel. 14 pre-2023 wave-pool heats (Surf Ranch 2018, Freshwater 2019, Jeep Surf Ranch 2021) carry the sentinel value -1 because WSL's leaderboard rendering for those years does not expose individual heat IDs. The verifier uses a leaderboard-format branch for these. No data is missing — only the WSL-side ID.

5. Source omissions in wave_range / wind_condition. WSL did not consistently publish wave range or wind condition for 2014–2017 events, and a few 2023 events have event-wide gaps (Pipe Pro, Portugal, Bells Beach). NULL means absent at source. ERA5 covers these gaps numerically.

6. ERA5 break coverage = 28 of 40 breaks. 98.5% of heats join. The 112 unjoined heats are at 12 breaks not yet pulled into ERA5Conditions — Surf Ranch, Surf Abu Dhabi, plus 10 lower-volume venues. Open-Meteo data is available for these; pulling it is straightforward future work.

7. Surfer height / weight ~40% populated. WSL profile pages omit these fields for many historical surfers. NULL = not published, not zero.

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Suggested uses

Fantasy surf league optimization. The dataset was originally built for this. Per-event point totals, per-surfer break-history aggregates, and ERA5 conditions are all queryable in SQL. See [GitHub repo / paper / blog post — TBD] for prior modeling experiments.

Educational ML. A worked example of a domain-expert-driven ML project from data collection through audit. The v4 build itself is a story — the project includes documented bug discoveries, parser corrections, and audit-driven verification. Useful for teaching how to build trustworthy data pipelines from scraped web sources.

Sports analytics research. Wave-by-wave granularity over 12 years, multi-tour, multi-venue, with weather covariates. Suitable for studying career trajectories, condition-performance interactions, head-to-head matchup outcomes, etc.

What this dataset is NOT. It is not an official WSL product. It is not real-time. It does not include video, replays, or judge-by-judge score breakdown (WSL does not publish per-judge scores in popup HTML for completed heats). It does not include interference Penalty-1 halving annotations (see Limitations).

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Schema details

Run .schema in sqlite3 against wsl-v4.sqlite for the canonical schema. Highlights:

Wave columns:

• wave_id (PK), heat_id, athlete_id, wave_index (1-based per surfer-heat)
• score (REAL) — WSL's displayed score, post-penalty if applicable. NULL for TBD waves.
• is_counted (INTEGER 0/1) — 1 if this wave is one of the surfer's top-2 (counts toward heat total).
• is_zeroed_by_interference (INTEGER 0/1) — 1 only for Penalty 2/3 strict zeroing (see Limitations).
• direction (TEXT) — "right" or "left" for wave-pool waves; NULL for ocean.

Heat columns:

• heat_id (PK), round_id, event_id, heat_number
• heat_date (TEXT YYYY-MM-DD), heat_duration (TEXT ISO-8601, e.g. PT30M)
• wave_range, wind_condition (TEXT — WSL's rendered strings, may be NULL for archive gaps)
• break_id (TEXT) — joins to Break and ERA5Conditions
• wsl_heat_id (INTEGER) — sentinel-aware: > 0 = popup-format with WSL-assigned ID; -1 = leaderboard-format pre-2023 wave-pool; never NULL
• data_quality_notes (TEXT) — non-NULL for ~35 heats with documented anomalies

Event columns:

• event_id (PK), name, year, tour ("MCT" or "WCT"), location
• break_id (TEXT) — default break for the event; heat-level break_id is authoritative for split events
• contest_start_date, contest_end_date, is_split_event (INTEGER 0/1)
• note (TEXT) — descriptive notes for calendar-straddling, COVID-disrupted, multi-break sourcing, etc.

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Citation

If you use this dataset in research, please cite:

@dataset{wsl_v4_2026,
  author       = {Friedlander, Mark},
  title        = {WSL Championship Tour Heat-Level Dataset (2014--2025), v4},
  year         = {2026},
  publisher    = {Hugging Face},
  url          = {https://huggingface.co/datasets/<TBD>}
}

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License

This dataset is released under Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0).

Required attributions:

• WSL data: Scraped from public results pages on worldsurfleague.com. Not an official WSL product.
• ERA5 weather data: "Weather data by Open-Meteo.com" (CC BY 4.0).

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Changelog

• v4 (2026-04-30, this release): Fresh recrawl of all competition data from WSL. Hash chain locked. ERA5 join coverage 98.5%. 365/365 stratified-sample heats verified clean. Audit verdict HEALTHY.