紐時賞析／聖嬰將臨 極端天氣機率上升

過去10年間，極端氣候事件在全球各地造成約2兆美元的損失。圖爲海倫颶風襲擊美國北卡羅來納州艾許維爾市之後留下大量淤泥。路透

Odds Rise That El Nino Will Soon Bring Weather Extremes

聖嬰將臨 極端天氣機率上升

An El Nino climate pattern that is likely to develop this summer may be severe, federal scientists warned Thursday in a forecast that raised threats of record heat, floods and other weather extremes around the planet this year and next.

聯邦政府科學家週四在預測報告中警告，今年夏天很可能形成的聖嬰現象將會相當強烈，這將提高今年與明年全球出現破紀錄高溫、洪水以及其他極端天氣所帶來的威脅。

The Climate Prediction Center, part of the National Oceanic and Atmospheric Administration, issued an El Nino watch estimating a chance of about 80% that the phenomenon known for boosting global warmth would arrive as soon as August — a significant change from a February prediction that suggested 60% odds that the pattern would develop in the fall. During an El Nino, warmer-than-normal waters in the central and eastern Pacific Ocean cause weather patterns to shift in ways that drive heat waves, drought and floods globally.

隸屬於美國國家海洋暨大氣總署的氣候預測中心發佈聖嬰警報，估計有大約80%的機率，這種以提升全球氣溫聞名的現象最早可能在8月出現——這比2月預測的秋季形成機率60%有大幅提高。在聖嬰期間，太平洋中東部海水溫度高於正常值，會導致全球天氣型態改變，進而引發熱浪、乾旱與洪水。

The researchers said there is about a one in three chance the next El Nino will be at least as strong as the last one, which pushed global temperatures in 2023 and 2024 above a long-feared warming threshold — 1.5 degrees Celsius above preindustrial norms — for the first time.

研究人員表示，下一次聖嬰有大約3分之1的機率，強度至少會和上一次一樣強烈，而上一次聖嬰已經讓2023年與2024年的全球氣溫，首度超過長期以來令人擔憂的氣候暖化門檻——比工業革命前平均值高出攝氏1.5度。

The forecast also raises questions about whether the United States is prepared for the disasters an El Nino can trigger or intensify. The Trump administration has let go thousands of Federal Emergency Management Agency workers since early last year. A plan to overhaul the disaster agency was in limbo even before President Donald Trump fired Kristi Noem, the Homeland Security Department secretary overseeing that work, last week.

這份預測也讓人質疑美國是否準備好因應聖嬰可能引發或加劇的災難。川普政府從去年年初起已裁撤數千名聯邦緊急事務管理署人員。川普上週解僱負責監督該工作的國土安全部部長諾姆之前，重整災難應變機構的計劃就已經陷入停滯。

“It’s like having a ship stall out in front of a tidal wave,” said Jesse Anttila-Hughes, an associate professor of economics at the University of San Francisco.

舊金山大學經濟學副教授安提拉-休斯用「一艘船在巨浪當前失去動力」，比喻美國的防災系統在面對來勢洶洶的聖嬰時顯得脆弱。

El Nino, a natural fluctuation involving shifts in Pacific tradewinds, last developed in May 2023 and persisted for a year, as it typically does. Scientists linked it to drought in southern Africa and flooding in the Horn of Africa; drought and wildfires in the Amazon; extreme heat stress on coral reefs; intense rainfall in Southern California; and record-low winter ice cover across the Great Lakes. The pattern also usually increases overall precipitation from Southern California to the Gulf Coast and Florida.

聖嬰是一種自然波動，涉及太平洋信風的改變，上一次在2023年5月形成，並持續了1年，這是它的典型演變時間。科學家將其與以下現象連結：南非乾旱、非洲之角洪水、亞馬遜乾旱與野火、珊瑚礁極端高溫壓力、南加州強降雨，以及五大湖區創紀錄的冬季低冰量。這種型態通常也會讓從南加州到墨西哥灣沿岸以及佛羅里達的整體降雨量增加。

The El Nino pattern, marked by warmer-than-average Pacific waters along the equator, is known in the United States for discouraging Atlantic hurricanes. But the 2023 Atlantic hurricane season was the fourth most active on record despite El Nino.

聖嬰型態的特徵是赤道沿線太平洋海水溫度高於平均值，在美國被認爲會抑制大西洋颶風形成。儘管2023年出現聖嬰，大西洋颶風季仍然創下史上第四旺盛的紀錄。

文／Scott Dance，譯／國際中心

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