Where will 2026 rank among the hottest years on record?

Platform comparison

Market context

Global temperatures in 2026 are projected to remain near 2025 levels as natural ocean cooling and ongoing La Niña conditions suppress record-breaking heat, though the year will almost certainly stay within the top ten hottest on record. The World Meteorological Organisation estimates an 86% probability that one year between 2026 and 2030 will surpass 2024 as the warmest ever, yet specific modelling for 2026 points away from a new peak [1].

Historical framing suggests the current 34% YES probability for 2026 ranking in the top three is optimistic relative to expert consensus. Berkeley Earth calculates a 51% chance of a fourth-place finish, with only a 10% probability of first place and 21% for second, implying the crowd is overweighting a top-three outcome [2]. This divergence contrasts with sportsbook-style lines that often lag behind specialist climate forecasts, where the 4th-place median is the dominant expectation rather than a podium finish.

Traders should monitor monthly Global Land-Ocean Temperature Index releases, particularly the June and July data expected in August, which will clarify if early-year warmth in January and May persists. May 2026 already ranked as the second-warmest May on record, but the cooling trend noted by Berkeley Earth suggests this may not translate to annual dominance [2][8]. The settlement depends entirely on the final index value once released, regardless of future revisions, making near-term monthly anomalies the primary catalyst for probability shifts.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

Resolution & payout

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

FAQ

Where can I trade this market with the lowest fees?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is Kalshi vs Polymarket. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

Is this market available outside the US?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

How does resolution work?

Through the UMA Optimistic Oracle on Polygon: a proposer submits the outcome, a two-hour challenge window opens, and USDC payouts settle automatically once the result is final.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Kalshi vs Polymarket trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.