Trade: Min Arctic sea ice extent this summer?

Market context

Arctic sea ice reaches its minimum extent in September each year, typically between late August and mid-September. This market settles on the lowest daily measurement recorded between 1 August and 1 October 2026, as tracked by the National Snow and Ice Data Center (NSIDC). The NSIDC uses satellite passive microwave data to measure ice extent to a precision of thousands of square kilometres, making this a quantifiable physical metric rather than a forecast estimate.

The current order book on Polymarket implies a 55% probability that Arctic sea ice extent will fall below a particular threshold this summer. Historical context shows that Arctic minimum extent has declined substantially over recent decades, with 2012 recording the lowest extent on satellite record at approximately 3.39 million square kilometres. Recent summers have seen minima ranging between 3.4 and 4.7 million square kilometres, with 2023 and 2024 both recording relatively low extents. The threshold embedded in this market's probability reflects where traders assess the likelihood of another notably low year relative to the recent distribution of observations.

Traders should monitor spring and early summer atmospheric patterns, particularly the North Atlantic Oscillation and Pacific conditions, which influence ice melt rates through June and July. Sea surface temperatures in the Arctic and subarctic regions will be critical; warmer conditions accelerate ice loss. Real-time NSIDC data releases occur regularly throughout the measurement window, allowing traders to update positions as the summer progresses and actual extent figures emerge. The market remains open until October data publication, creating a settlement lag of several weeks after the physical minimum occurs.

How this market resolves

Resolution is handled by the UMA optimistic oracle on Polygon. A proposer submits the outcome, a two-hour dispute window opens, and if no one stakes a counter-claim the payout is final. Contested outcomes escalate to UMA token-holder voting. Payouts clear in USDC to the winning side.

How to trade this market step by step

The mechanics for trading "Min Arctic sea ice extent this summer?" are the same as any other PolyGram event contract. Each YES share resolves to $1 if the event happens, or $0 if it doesn't. The current price between 0¢ and 100¢ is the market's probability estimate, set live by the order book.

1. Sign in on polygram.ink with your email — no full KYC under $1,500 lifetime trading volume.
2. Deposit USDC on Polygon (lowest fees, ~$0.01 per transaction) or Ethereum. Funds credit after 12 confirmations.
3. Pick a side. Buy YES if you believe the event will happen; buy NO if you think it won't. The current YES price reflects the market's collective probability.
4. Size your position. If you stake 100 USDC at 50% YES, you'll receive shares that pay $200 if YES resolves true — a 100% gross return. If NO resolves, your shares are worth $0.
5. Set risk controls (optional). Stop-loss, take-profit, and limit-order types all supported. Use the trade ticket's slippage box to cap your maximum entry price.
6. Wait for resolution. When the event resolves on-chain via the UMA optimistic oracle, the winning side settles to 100¢ automatically and USDC hits your balance within seconds. Withdrawable to any wallet you control.

How active is this market?

$48K in lifetime turnover and $13K of resting liquidity puts this market in the above the median by volume for weather contracts on PolyGram. Order-book depth is modest — expect a couple of cents of slippage on $1k+ trades.

Last 24 hours alone saw $13K in turnover, well above the lifetime daily-average for this market — a clear sign of news catalysing trader activity right now.

The market has been open for 6 months — the price has had time to stabilise as new information arrived.

Higher-volume markets tend to have tighter spreads and faster price discovery — meaning the displayed YES/NO percentages are more likely to reflect the true crowd-implied probability rather than a single trader's directional view.

Key terms

YES / NO share

A binary outcome token that pays $1.00 if the underlying claim resolves true (YES) or false (NO), and $0 otherwise. The market price between 0¢ and 100¢ is the implied probability.

CLOB

Central limit order book. The matching engine that pairs YES buyers with NO buyers (effectively the same trade). Polymarket's CLOB on Polygon executes trades on-chain via the conditional-tokens framework.

Liquidity

USDC capital sitting in resting limit orders inside the order book. Deeper liquidity means smaller slippage on large trades and a tighter bid-ask spread.

UMA optimistic oracle

The on-chain dispute system that settles each Polymarket market. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution.

Slippage

The difference between the displayed mid-price and your fill price. Affects market orders most; limit orders avoid slippage but may take time to fill.

Conditional token

ERC-1155 outcome share issued by Gnosis Conditional Tokens on Polygon. The token type that resolves to $1.00 or $0.00 at settlement.

See the full prediction-market glossary →

Frequently asked questions

Risk and regulatory note

Prediction-market positions can lose 100% of staked capital. Outcomes are uncertain by definition — historical accuracy of crowd-implied probabilities is high in aggregate but not for any single market. PolyGram does not provide investment advice. Trade only with capital you can afford to lose.

Regulatory status varies by jurisdiction. Germany, the United States, and most EU countries treat Polymarket-style event contracts under one of three frameworks: financial derivative, gambling product, or unregulated novel asset. Consult local counsel before trading.

Related prediction markets

Explore more prediction market odds and trading opportunities on PolyGram:

• All weather prediction markets
• How prediction markets work
• Browse all prediction markets on PolyGram
• Top prediction market traders
• Back to PolyGram home