Where will 2026 rank among the hottest years on record?

Platform comparison

Market context

Global land-ocean temperatures in 2026 are currently tracking as the second-warmest June on record, trailing only 2024, with ocean surfaces hitting an all-time monthly high [2]. This intense early-year heat frames the market’s 32% YES probability that 2026 will rank as the single hottest year, a threshold James Hansen argues is likely to be breached if the year exceeds 2023 by 0.17°C [1]. However, Berkeley Earth counters this optimism, noting that the ongoing La Niña phase should keep 2026 cooler than both 2023 and 2024, projecting a fourth-place finish instead [3]. The divergence between Hansen’s physics-based prediction of a record break and Berkeley Earth’s La Niña-adjusted model creates the pricing tension traders are betting on.

On-chain, Polymarket users are trading USDC on Polygon using conditional tokens to capture this volatility, where the settlement hinges on the Global Land-Ocean Temperature Index once data becomes available. Key catalysts include the transition from La Niña to neutral or El Niño conditions, which could accelerate warming in the latter half of the year. The World Meteorological Organisation recently flagged an 86% chance that one year between 2026 and 2030 will surpass 2024 as the warmest on record, making the timing of this shift critical [4]. Traders must monitor monthly NCEI outlooks and sea surface temperature anomalies, as the globe’s second-warmest June suggests the underlying heat is already embedded despite the cooling phase [2].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to Kalshi UK, which mirrors the Polymarket order book directly.

Resolution & payout

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

FAQ

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.

What does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.

Do I need to KYC for this market?

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