One consistent theme of the 2023 summer is, almost beyond any doubt, the relentless heat.

Most regions of China are forecast to experience their first heat wave of the year this week, with maximum temperatures soaring to 37 degrees Celsius in some areas, the China Meteorological Administration said on Monday.

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Beijing, capital of the country, together with parts of northern China, sizzles under one of the worst heat waves in history.

The observatory in southern Beijing on Saturday for the first time recorded temperatures above 40 C for a third consecutive day, according to the meteorological authorities.

In nearby Hebei province and the port city of Tianjin, temperatures have also soared above 40 C over the past few days, prompting authorities to issue “red” alerts for extreme weather, the highest in China’s four-tier weather alert system.

On Thursday, Beijing experienced its second-hottest day on record – with temperatures soaring to 41.1 C. It was also the highest temperature ever recorded in China’s capital during the month of June.

Chinese meteorologists say the current heat wave has been caused by warm air masses associated with high-pressure ridges in the atmosphere and compounded by thin cloud covers and long daylight hours around the summer solstice.

China issued the first forecast for high temperatures and heat stroke for this year on June 15, 13 days earlier than the average release date of most years.

Entering June, record-breaking readings on the thermometer has made it clear that after months of warning, El Ni?o has officially arrived— and it may be the hottest in human history.

Earlier this month, scientists at the US National Oceanic and Atmospheric Administration (NOAA)confirmedthat the climate event known as El Ni?o has officially emerged for the first time in more than four years, and it’s expected to bestrongthis time around.

An El Nino system is building along the equator in the eastern Pacific Ocean, which could send global average temperatures soaring to a record high this year or in 2024, the China Meteorological Administration said.

Other countries in Asia have experienced deadly heat waves in recent weeks, which scientists say are aggravated by rising global temperatures.

Since the beginning of June, heat waves have resulted in nearly 100 deaths in two of India’s most populous states. In Spain, recent high temperatures are dealing a blow to farmers who have yet to recover from last year’s drought. In the US, Texas power prices surged 80% this week as a heat wave put added strain on the grid.

“Super El Ni?o”

The entire world has been experiencing extreme temperatures. Researchers have indicated that with rising ocean temperatures worldwide and the onset of El Ni?o in the Pacific, 2023 could potentially become the hottest year on record, according to a report from China Science Daily.

Climate scientists have predicted there is a 90 percent chance that the phenomenon will take hold in the latter half of the year. Its impacts are unlikely to be felt until the end of the year, but there is concern it could develop into a "super El Nino".

The World Meteorological Organization (WMO) released a report on May 17 stating that due to the accumulation of greenhouse gases and the influence of natural El Ni?o events, global temperatures may reach record levels in the next five years. It assigns a 98 percent probability to the average temperature from 2023 to 2027 being hotter than the past five years.

So how does El Ni?o form and what to expect during one?

Occurring every three to seven years, an El Ni?o describes theunusual warming of the eastern Pacific Ocean, just off the coast from Peru. The phenomenon is declared when sea temperatures in the region rise 0.5 °C above the long-term average.

This subsequently drives surface air temperatures and pressure changes throughout the equator, which then go on toaffect seasonal weather over both hemispheres.

The event is driven by slow, natural fluctuations in ocean currents and wind patterns, but the climatic impacts are felt over many months – and even years – across the planet.

The hottest years on recordtend to happen during El Ni?o. The last major El Ni?o from 2014 to 2016 led to each of those years successively breaking the global temperature record and 2016 remains the hottest year ever recorded.

Variations in wind strength and ocean temperatures in the vast Pacific Ocean lead to two distinct climate patterns, El Ni?o and La Ni?a. The switch between them happens irregularly, every three to seven years, usually with neutral years in between. El Ni?os tend to last about a year but the La Ni?a phase can be longer, and 2023 has brought the end of an unusual run of three successive La Ni?a years.

There is a potential swift switch this year from the La Ni?a period, toward the El Ni?o phenomenon, said Ma Jun, director of the Beijing-based Institute of Public and Environmental Affairs.

The fallout of El Ni?o not only includesincreased global temperatures and more frequent and severe wildfires and power outages, but also heightened rainfall, intense flooding and droughts, and mass fish die-offs. The list goes on.

But it’s worth noting that a country’s experience of El Ni?o varies from region to region and season to season, and is dependent on the intensity of the phenomenon when it comes to pass.In parts of the world, like the baked, semi-arid mid-west of the US, an El Ni?o can bring increased rainfall during the summer months. Conversely, it can drive unusually warm temperatures and dry conditions in regions of Africa that are normally very wet.

Costs of extreme weather

The main concern from the changing El Ni?o-Southern Oscillation (ENSO) cycle is that it brings more catastrophic events such as wildfires or floods creating humanitarian crises and major ecological damage, which come with economic costs.

Less immediately visible will be its economic effects: El Ni?o is set to aggravate the failure of the prevailing growth-based economic model, with calamitous results for the world’s poor.

However, scientists do not always see eye to eye when it comes to the damage of El Ni?o on the economy. A recent research by Callahan and Mankin, which has been widely cited in the media, attribute “$4.1 trillion and $5.7 trillion in global income losses to the 1982-83 and 1997-98 El Ni?o events”.

Researchers at Oxford Economics are skeptical of these results. According to Ben May, director of Global Macro Research at Oxford Economics, the damage bill from a natural disaster can be huge for an individual economy. But at the global level, total annual damage costs from natural disasters are typically small, when measured as a share of annual world output.

In 2011, a bad year for natural disaster damage, the estimated cost of global damage was about 0.5 percent of nominal US dollar-weighted global GDP. From 2019 to 2021, the cost has averaged less than 0.2 percent of global GDP.

The impact of El Ni?o on crops and food prices is uncertain as well, as academic studies suggest that the impact of ENSO on the yield of key crops is small at a global level. While the yield from large areas of cultivated land may fall significantly due to El Ni?o or La Ni?a, causing price surges in these regions, other regions may benefit from significantly higher yield. For instance, El Ni?o causes a reduction in mean global rice and wheat yield of about 1.3 percent and the adverse impact on corn is relatively small, whereas soybean yield typically increase.

However, the IMF Working Paper also shows that ENSO can account for almost 20 percent of real commodity price inflation over a multi-year period.

Higher food prices are a common theme across El Ni?o events, according to a recent Deutsche Bank report.

According to Bloomberg Economics modeling, previous El Ni?os resulted in a marked impact on global inflation, adding 3.9 percentage points to non-energy commodity prices and 3.5 points to oil.

今夏以來，我國提早開啟了“淄博燒烤”模式：多地氣溫爭先恐后沖上40℃，2023年會(huì)成為“史上最熱夏天”嗎？

先是從5月份開始至6月10日，云南、四川、貴州、廣西、廣東等地，陸續(xù)出現(xiàn)高溫天氣。

接著，北方也開始了高溫。6月11日，新疆包攬了我國高溫排行榜前十位。石河子出現(xiàn)6月首個(gè)40℃的高溫、托克遜連續(xù)兩天46℃、艾丁湖氣象站出現(xiàn)48.5℃的高溫，躋身全球高溫榜前列。

6月中旬以來，京津冀區(qū)域氣溫迅速攀高。其中，北京、天津、河北中南部和東北部最高氣溫在38℃~41℃。區(qū)域最高氣溫出現(xiàn)在22日北京懷柔區(qū)湯河口站、天津?yàn)I海新區(qū)大港站，均達(dá)到41.8℃。北方多地37℃以上的高溫影響面積約45萬平方公里，京津冀和山東等地有21個(gè)國家氣象站日最高氣溫突破歷史極值；南方地區(qū)大范圍強(qiáng)降雨持續(xù)，100毫米以上降雨覆蓋面積達(dá)20.57萬平方公里。

從6月27日開始，新一輪高溫又將上線，提升京津冀地區(qū)“炎值”，預(yù)計(jì)北京、天津、河北南部還會(huì)出現(xiàn)40℃以上的超高溫天氣。7月1日高溫范圍和強(qiáng)度達(dá)到最大，并有可能打破歷史極值，具有一定極端性。

目前預(yù)計(jì)，京津冀地區(qū)的整個(gè)6月高溫日數(shù)有望突破同期紀(jì)錄——12.1天（1972年6月）。

不僅是中國，“200年一遇”的熱浪讓東南亞措手不及。

早在今年4月，泰國就刷新了歷史上最高溫的紀(jì)錄，氣溫達(dá)45.4攝氏度，而鄰國老撾5月份也連續(xù)兩天達(dá)到43.5攝氏度的最高氣溫。6月1日，越南打破了歷史上最熱的6月紀(jì)錄，氣溫達(dá)到43.8攝氏度。再加上高濕度，東南亞的酷熱變得更加難以忍受和危險(xiǎn)。

罕見的熱浪同樣襲擊了歐美。美國得克薩斯州、新墨西哥州等地氣溫持續(xù)刷新紀(jì)錄，數(shù)千萬人處于極端高溫預(yù)警之下。部分地區(qū)氣溫刷新了有記錄以來的最高值。歐洲想方設(shè)法應(yīng)對高溫，德國地方設(shè)立抗旱專員職位，荷蘭將啟動(dòng)國家高溫計(jì)劃，西班牙縮短學(xué)校上課時(shí)間。

今夏以來，北半球多地遭遇極端高溫，伴隨著這些高溫天氣，有一個(gè)詞會(huì)被經(jīng)常提及：厄爾尼諾。

厄爾尼諾，真的來了

6月以來，赤道中東太平洋海表溫度明顯上升，目前已進(jìn)入厄爾尼諾狀態(tài)。據(jù)國家氣候中心預(yù)測，未來三個(gè)月赤道中東太平洋將維持厄爾尼諾狀態(tài)，海溫指數(shù)持續(xù)上升，將在今年秋季形成一次中等以上強(qiáng)度的東部型厄爾尼諾事件。

美國海洋和大氣管理局（NOAA）近日發(fā)布的厄爾尼諾現(xiàn)象觀察報(bào)告預(yù)計(jì)，在今年5月至7月期間，“厄爾尼諾”出現(xiàn)的幾率為62%。根據(jù)NOAA氣象學(xué)家休瑞的說法，今年之內(nèi)全球出現(xiàn)“厄爾尼諾”現(xiàn)象的概率超過85%。休瑞表示，“我們目前看到熱帶太平洋有大量的次表層海洋熱量在積累，這些熱量最終會(huì)涌向海面?！彼J(rèn)為，“厄爾尼諾”現(xiàn)象正在持續(xù)醞釀中，“證據(jù)已經(jīng)非常清晰”。

今年5月17日，世界氣象組織（WMO）發(fā)布的報(bào)告顯示，全球氣溫在未來五年可能會(huì)達(dá)到創(chuàng)紀(jì)錄的水平，這主要受到溫室氣體的積聚和自然發(fā)生的厄爾尼諾現(xiàn)象的影響。

報(bào)告指出，有98%的可能性，在未來五年中至少有一年，以及整個(gè)五年，將是有記錄以來最熱的年份。

此次厄爾尼諾出現(xiàn)時(shí)間比預(yù)想提前一到兩個(gè)月，且發(fā)展較快，到冬季發(fā)展為強(qiáng)厄爾尼諾的概率為56%。

如果出現(xiàn)強(qiáng)厄爾尼諾，2024年將很有可能成為有記錄以來最熱的一年。但明年是否會(huì)受厄爾尼諾影響成為有氣象記錄以來最熱的一年，仍有不確定因素。

簡單而言，厄爾尼諾是指赤道中東太平洋海表溫度持續(xù)、顯著偏暖的氣候現(xiàn)象。正常情況下在信風(fēng)帶影響下，大量溫暖的海水自東向西流動(dòng)，形成了穩(wěn)定的洋流。這種洋流造成太平洋西側(cè)海水溫度偏高。而東側(cè)海水溫度則較低，空氣相對干燥，氣候也就相對干旱。

但是在有些年份或一年中的某些月份，信風(fēng)強(qiáng)度異常減弱，造成赤道地區(qū)自東向西流動(dòng)的洋流減弱，西太平洋的海水溫度異常降低，本來比較濕潤的氣候趨于干旱，原本干旱的氣候趨于濕潤。

簡單的說，就是應(yīng)該多雨的地方降水減少了，應(yīng)該干旱的地方降水卻在增加，這便是厄爾尼諾現(xiàn)象。

專家表示，在全球變暖背景下，疊加中等以上強(qiáng)度厄爾尼諾事件，可能導(dǎo)致極端天氣頻次更多、范圍更廣、強(qiáng)度更強(qiáng)。

1951年以來，赤道中東太平洋共發(fā)生了21次厄爾尼諾事件，曾給我國帶來高溫?zé)崂恕⒑闈澈透珊档扔绊憽?/p>

國家氣候中心分析歷史數(shù)據(jù)發(fā)現(xiàn)，厄爾尼諾發(fā)展年夏季，華北南部、華中北部、華東中部、西北地區(qū)東部等地氣溫易偏高，部分地區(qū)高溫日數(shù)可達(dá)30天以上。

“厄爾尼諾發(fā)展年夏季，西太平洋副熱帶高壓往往偏南偏強(qiáng)，造成我國南方地區(qū)降水偏多。近期江南、華南等地強(qiáng)降水頻發(fā)就是受到厄爾尼諾狀態(tài)影響的體現(xiàn)之一。”中國氣象局氣候服務(wù)首席專家周兵說。

而厄爾尼諾通常伴隨著拉尼娜的到來，這是兩種對立的反常自然現(xiàn)象，原因在于信風(fēng)和洋流的異常。據(jù)國家氣候中心預(yù)測，在厄爾尼諾發(fā)展加強(qiáng)背景下，預(yù)計(jì)今年夏季我國華東南部、華中南部、西南地區(qū)南部降水易偏多，發(fā)生洪澇的風(fēng)險(xiǎn)大；西北地區(qū)東部降水易偏少，發(fā)生氣象干旱的可能性大。而拉尼娜現(xiàn)象則會(huì)造成長江流域出現(xiàn)干旱，北方降水異常偏多，在拉尼娜現(xiàn)象出現(xiàn)的冬季極易形成雪災(zāi)。

不過，專家表示，影響我國氣候異常尤其是高溫、干旱、洪澇等極端事件的因子復(fù)雜，厄爾尼諾只是其中一個(gè)重要因子。

中國科學(xué)院大氣物理研究所季風(fēng)系統(tǒng)研究中心副主任魏科認(rèn)為，高溫天氣不可避免，因?yàn)槟壳俺龞|太平洋外，已逐漸出現(xiàn)偏暖跡象，但是今年的厄爾尼諾現(xiàn)象沒有2016年的超級厄爾尼諾現(xiàn)象那么強(qiáng)，未必能達(dá)到“史上最熱夏天”。

厄爾尼諾“定損”不易

通常來講，“厄爾尼諾”現(xiàn)象會(huì)使全球氣候模式趨于不穩(wěn)定，災(zāi)害天氣頻發(fā)。在厄爾尼諾年，東南亞、澳大利亞、南亞次大陸等區(qū)域可能出現(xiàn)干旱天氣，而從太平洋中部赤道地區(qū)到南美大陸西岸可能降雨增多，意味著拉丁美洲（尤其是巴西和阿根廷）可能出現(xiàn)洪災(zāi)。

惡劣的氣候也會(huì)給全球糧食供應(yīng)帶來壓力。干旱和洪災(zāi)等天氣會(huì)直接擾亂糧食生產(chǎn)秩序，而且氣溫持續(xù)升高帶來的熱力效應(yīng)也會(huì)降低土壤肥力和糧食產(chǎn)量。受氣溫升高的影響，糧食作物的品質(zhì)會(huì)下降，從而增加了糧食浪費(fèi)的可能性，進(jìn)一步增加饑餓人口的數(shù)量。

世界氣象組織(WMO)近日發(fā)文稱，年內(nèi)出現(xiàn)厄爾尼諾氣候現(xiàn)象的可能性越來越大，預(yù)計(jì)將帶來高溫和極端天氣，進(jìn)一步影響糧食安全問題，多個(gè)主要谷物生產(chǎn)國和出口國將面臨風(fēng)險(xiǎn)。進(jìn)入6月，受關(guān)鍵產(chǎn)區(qū)惡劣天氣導(dǎo)致作物減產(chǎn)的擔(dān)憂升溫，國際小麥、玉米、大豆期貨開啟了新一輪漲價(jià)行情。

按照國際貨幣基金組織（IMF）發(fā)布的報(bào)告，厄爾尼諾事件不僅對當(dāng)年全球經(jīng)濟(jì)造成沖擊，也會(huì)導(dǎo)致隨后多年經(jīng)濟(jì)體增長乏力。IMF預(yù)計(jì)，新一輪強(qiáng)勁的厄爾尼諾影響將更為嚴(yán)重，可能在長達(dá)十年的時(shí)間里抑制熱帶國家的經(jīng)濟(jì)活動(dòng)。

報(bào)告稱，厄爾尼諾現(xiàn)象對不同地區(qū)的經(jīng)濟(jì)影響存在較大差異。主要經(jīng)濟(jì)體中澳大利亞、智利、印度、印尼、日本、新西蘭和南非的經(jīng)濟(jì)活動(dòng)都會(huì)因?yàn)闅夂驔_擊而短暫下降，而美國、加拿大、墨西哥、泰國等經(jīng)濟(jì)體和歐元區(qū)可能從中受益。

厄爾尼諾會(huì)為全球經(jīng)濟(jì)帶來不確定性，而具體對經(jīng)濟(jì)產(chǎn)生多大的影響，科學(xué)界卻未有定論。

近日，美國科學(xué)家在《科學(xué)》發(fā)布報(bào)告稱，厄爾尼諾現(xiàn)象預(yù)計(jì)在今年再次出現(xiàn)，并將在全球范圍內(nèi)造成數(shù)萬億美元的經(jīng)濟(jì)損失。這項(xiàng)研究是第一批評估厄爾尼諾現(xiàn)象長期損失的研究之一，其預(yù)測的損失遠(yuǎn)遠(yuǎn)超過之前的研究。

該報(bào)告的研究人員分析1982年至1983年和1997年至1998年厄爾尼諾事件后幾十年的全球經(jīng)濟(jì)，發(fā)現(xiàn)了經(jīng)濟(jì)增長放緩的“持久特征”，即在每一次事件發(fā)生后的5年里，全球經(jīng)濟(jì)分別損失了4.1萬億美元和5.7萬億美元，其中大部分由貧窮的熱帶國家承擔(dān)。

研究人員預(yù)測，鑒于氣候變化可能會(huì)加劇厄爾尼諾現(xiàn)象的出現(xiàn)頻率和強(qiáng)度，即使世界各國減少碳排放的承諾成為現(xiàn)實(shí)，21世紀(jì)全球經(jīng)濟(jì)損失也將達(dá)到84萬億美元。他們估計(jì)，到2029年，僅2023年的厄爾尼諾現(xiàn)象就可能給全球經(jīng)濟(jì)造成3萬億美元的損失。到本世紀(jì)末，厄爾尼諾現(xiàn)象將影響約84萬億美元的GDP增長。其中，熱帶和南半球地區(qū)的風(fēng)險(xiǎn)最為嚴(yán)重。

然而，有經(jīng)濟(jì)學(xué)家對此結(jié)論表示質(zhì)疑。牛津經(jīng)濟(jì)研究院全球宏觀研究主任Ben May認(rèn)為，厄爾尼諾現(xiàn)象對全球經(jīng)濟(jì)的影響是復(fù)雜和不均衡的。一方面，有些國家和地區(qū)可能因?yàn)槎驙柲嶂Z現(xiàn)象而受益，例如北美、歐洲、澳大利亞等溫帶地區(qū)，可能會(huì)有更溫暖和濕潤的氣候，有利于農(nóng)業(yè)生產(chǎn)和能源消費(fèi)。比如厄爾尼諾現(xiàn)象發(fā)生時(shí)，美國的西部地區(qū)一般是偏暖干，美國的東南部分，一般會(huì)偏暖濕一些，南美洲降水偏多，會(huì)影響到這一地區(qū)農(nóng)產(chǎn)品的產(chǎn)量，尤其像玉米、大豆、小麥等作物。當(dāng)這一地區(qū)降水偏多時(shí)，有助于農(nóng)作物產(chǎn)量的增加，其價(jià)格也會(huì)有所降低。

另一方面，有些國家和地區(qū)可能因?yàn)槎驙柲嶂Z現(xiàn)象而受損，例如南美、非洲、亞洲等熱帶和亞熱帶地區(qū)，可能會(huì)遭受更嚴(yán)重的干旱或洪水，影響農(nóng)業(yè)和漁業(yè)產(chǎn)量和質(zhì)量。

May強(qiáng)調(diào)，厄爾尼諾現(xiàn)象不會(huì)改變?nèi)蚪?jīng)濟(jì)的基本趨勢和結(jié)構(gòu)，而是暫時(shí)性的沖擊。他預(yù)計(jì)，厄爾尼諾現(xiàn)象對全球經(jīng)濟(jì)增長率的影響不會(huì)超過0.1個(gè)百分點(diǎn)。

Executive Editor: Sonia YU

Editor: LI Yanxia

Host: Stephanie LI

Writer: Stephanie LI

Sound Editor: Stephanie LI

Graphic Designer: ZHENG Wenjing, LIAO Yuanni

Produced by 21st Century Business Herald Dept. of Overseas News.

Presented by SFC

編委: 于曉娜

策劃、編輯：李艷霞

播音：李瑩亮

撰稿：李瑩亮

音頻制作：李瑩亮

設(shè)計(jì)：鄭文靜、廖苑妮

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