|
人口與生態危機 -- 開欄文
|
瀏覽4,158 ｜回應17｜推薦1 |
|
|
|
過去一年多，俄烏戰爭一直佔著新聞版面重心；最近兩、三星期來，以巴戰爭則取而代之。本欄呈現人類二、三十年來共同面臨的重大議題：人口與生態危機。
第二篇文章的作者指出：瑞斯教授的「警告」可能近於危言聳聽，但我們必須正視他提出的「人口與生態危機」。
第三篇文章報導氣候學家們最近提出的一篇研究結果。該研究的數據與分析顯示：「人口與生態危機」持續惡化。
第四篇文章批評主流氣候學家們進行「研究」所根據的「基本前提」；我是個門外漢，此處只做存檔備查的動作。
本文於 修改第 1 次
|
|
全球暖化與尼泊爾災情相關 -- Damien Gayle
|
|
|
推薦1 |
|
|
|
這篇關於尼泊爾災情「科學研究報告」的報導，佐證了張智北博士在本欄上一篇《「全球暖化」議題二、三事》第1.1小節所做精簡分析。
Climate crisis probably weakened glacier that caused devastating Nepal-Tibet floods, first study finds
Scientists say global heating was a destabilising factor in collapse of 200,000 sq metre glacier in August
Damien Gayle, 09/17/26
Climate breakdown probably weakened the glacier that collapsed causing catastrophic floods and killing over a thousand people in Nepal and Tibet last month, the first scientific study of the disaster has found.
Researchers identified unusually warm conditions before the glacier's collapse, which sent an avalanche of 110m cubic metres (3.885bn cu ft) of snow and ice into the valley below. This triggered flash floods on an almost unprecedented scale, hitting communities downstream without warning.
"Communities in Nepal are paying with their lives for a crisis driven by fossil fuel emissions thousands of miles away," said Dr Friederike Otto, a climate science professor at Imperial College London, which carried out the study.
"When warming destabilises the roof of the world, no amount of local adaptation can fully shield vulnerable people downstream from this scale of destruction. Without much faster action to transition to zero fossil fuel emissions we will inevitably see more disasters of this scale occurring in the years to come."
More than 1,300 people were killed and more than 5,000 people remain missing after a massive section of overhanging glacier and rock measuring roughly 200,000 sq metres (2,153,000 sq ft) fell from Langtang Lirung mountain on 26 August. (Langtang Lirung mountain：朗唐利龍峰，又譯朗當利龍峰、藍塘里壤峰)
It dropped about 1,400 metres (4,660ft), slamming into the valley floor with such intensity that it registered as an earthquake, liquidising ice and sparking a freezing flood that careened downriver at speeds exceeding 110 mph.
The devastating flood of water, ice, rock and sediment swept away families, homes, settlements, roads, bridges and other infrastructure, leaving survivors stranded and cut off.
"Rock avalanches of this size are rare, with annual frequency estimates of approximately one event this size every 1,000–10,000 years," the study said. "This event shows that limits to adaptation are already being reached."
The research was unlike previous studies by Otto and her team at World Weather Attribution (WWA) – a collaborative project between Imperial and other climate specialists worldwide – in that the role of climate breakdown could not be ascribed to one particular weather event.
Instead, the researchers found the disaster was the result of a compound crisis, with a number of factors made worse by decades of atmospheric heating as a result of greenhouse gas pollution.
Dr Ben Clarke, who researches extreme weather and climate change at Imperial, said the "fingerprints of climate change" were clear in the long-term changes that happened around the glacier before its catastrophic collapse.
Among the study's key findings were:
* In the region where the collapse happened, climate breakdown has caused about 2C of warming since pre-industrial times, and about 1.5C of warming in July and August specifically;
* July and August 2026 were the warmest on record locally, reaching 5C above the 30-year average in the days before the collapse;
* The freezing threshold in the Himalayas has risen by about 100 metres per decade since the 1980s, with higher and longer thaw temperatures weakening mountain slopes shaped by permafrost;
* The warming temperature had already driven substantial glacier recession, removing stabilising ice from around the site where the collapse occurred and contributing meltwater;
* A 7.8 magnitude earthquake in 2015 further contributed to slope failure, though its specific contribution to the disaster in August could not be confirmed.
Otto, Clarke and the WWA team said their study did not directly ascribe climate breakdown as the fundamental cause of the catastrophe. Instead, it was best understood as a destabilising factor on the existing geology.
Clarke said: "We found that climate change is transforming the high mountain environment, influencing many of the possible drivers of this collapse."
Nepal has filed a formal request with the UN loss and damage fund for financial support to address the destruction caused by the flood, a process that requires proof of a link to the climate crisis. The country's foreign minister, Shisir Khanal, has also demanded that top emitting nations such as China and India "wake up" and accept shared responsibility for the disaster.
Madhab Uprety, senior technical advisor for the Red Cross Red Crescent Climate Centre, which is part of WWA, said only aggressive cuts to global emissions could begin to address the "losses and damages faced by vulnerable frontline communities".
He added: "In addition to the human tragedy on an unimaginable scale, the cost of recovery for this disaster is substantial. For a nation that's done virtually nothing to contribute to this problem, it underlines the need to find fairness in helping climate vulnerable nations cope with the problems they have not unleashed."
• This article was amended on 17 September 2026. The original version miscalculated a conversion from cubic metres to cubic feet.
相關報導
* How the deadly Nepal and Tibet flash flood unfolded – a visual guide
本文於 修改第 2 次
|
|
「全球暖化」議題二、三事 -- 張智北
|
|
|
推薦1 |
|
|
|
全球暖化：回應承渝兄
張智北，09/08/26
0. 前言
我完全了解承渝兄的論述；看起來是很清楚暖化會在各種方面傷害中國。冰川融化是我在北加州台大校友會6/20演講的一個重點，那會影響整個新疆的未來，絕非與普通人無關。事實上，影響中國幾十年後的前途關係可大了。
可是，另外確有一個暖化的結果是對中國可能有極大的正面影響，就是北方大片的沙漠乾旱地區可能乾旱會減少。歷史上這些乾旱和它所帶來的地貌變化如黃河改道造成過多次大飢荒和改朝換代，包括西漢，東漢，元，明的滅亡。
中國面積和美國差不多，人口多四倍，可耕地缺少得多。北方旱區是這個問題裡很大的一部分。暖化如果改善北方旱區，它可能緩解歷史上國家興亡的天災。
下面較短的1.1小節是我在臉書上發的帖子。時間在尼泊爾洪水成災後兩天；1.2節略長，是我在北加州台大校友會訊上的演講花絮(1)。第1.2節裏有我之前兩小時演講的「超連結」(2)。
1. 「全球暖化」分析
1.1 尼泊爾慘劇原因簡析
兩個月前在北加州台大校友會「氣候變化全球暖化」talk中，說到高山冰川溶化才讓新疆現在農業暫時繁榮，甚至沙漠養魚。聽眾大概記得在比較南疆和加州類似問題的投影片裡，提到了很少人知道的塔里木盆地沙漠洪水。
昆崙山在西藏高原之北；高原之南則是喜馬拉雅山；都有冰川在溶化。有報導說這次滑坡慘劇是冰川崩裂又碰到地震，非常罕見甚至從未發生過。其實當地、當時並沒有地震。
原因很簡單：正是冰川溶化。冰川幾千萬年來已經是高山峻嶺的一部分；因為山體岩石被侵蝕和裂縫，冰和石塊雜處結為一體。冰川溶化時，靠冰支持的基岩塊鬆動，重力造成冰、岩一起崩塌造成慘劇。也讓很多國家測量到地震度數。在那次演講中我曾談到：塔里木盆地的定時炸彈(冰川退縮地下水乾枯)，大概會發生在世紀中。所以這種冰岩崩塌還會發生大概三十年。
2. 「氣候變化，全球暖化及其影響」演講要點與花絮
張智北學長自1972年研究所畢業後來到灣區，至今已超過半個世紀。過去，他總覺得自己與校友會距離有些遙遠，曾笑說：「現在校友會活動的主角，不只是我的學弟妹，可能還有我學生的學生，大概沒有我的份了。」沒想到，在前前前會長劉麗美的邀請下，近兩年他積極參與校友會活動。他還特別補充：「我不是指在聊天群裡罵來罵去的……」一句話引起全場笑聲。其實，群組中常見學長直率幽默的分享，而對時事、科學與人生的深度思考，更展現他長年不變的熱情。
演講開始前，還發生了一段小插曲。我到洗手間後返回會場，遇見一位先生也正要進場，兩人卻怎麼也打不開厚重的大門。摸摸口袋，才發現彼此都沒帶手機，只能敲門求救。偏偏會場隔音極佳，裡面毫無反應。我靈機一動問：「您是張教授嗎？」他笑著回答：「是啊！」原來主講人就在我身旁。
站在門外，學長笑說：「這跟我兩年前那場 Zoom 演講一樣，大家都在線上等著，只有我進不去 Zoom」。這一次，他不再孤軍奮戰，還有幾位晚到校友一起陪伴。第一次見到張教授，竟是在會場門外；而兩次受邀演講，都遇到「主講人被擋在門外」的趣事，也成為這場演講前最特別的開場。
演講中，學長回顧近兩年在校友會的三個事件：從「科學與宗教」、紀念林孝信學長的文章，到今天的氣候變化主題。看似不同，其實都有共同核心——以科學理解自然，以關懷回應世界，順應自然之力量force。
第一件事，他說，常有人問：「連下星期的天氣都預報不準，怎麼能預測下個世紀全球會暖化？」天氣是典型的渾沌(chaotic)系統，初始條件只要有極微小的誤差，結果便會完全不同。雖然我們無法準確預報十天後的溫度，但是卻能預測六個月以後會很熱(因為夏天到了)，就是因為後者有地球繞太陽公轉形成的forcing。因此，自然界的變化可分成兩種：一種來自系統內部的自然變化(natural)，另一種則是外在力量造成的強迫變化(forced)。這樣的思考，給了他「科學與宗教」演講裡自然神學的靈感，也是今天探討氣候變化的思維背景。
第二件事，學長在《北加州台灣大學校友會年刊2026》發表《追憶林孝信：創辦《科學月刊》影響台灣知識份子超過半世紀的台大校友》，紀念他最敬重的同學林孝信。1970年，林孝信創辦《科學月刊》，希望讓科學知識在台灣扎根；第二期出版後，又因投入保釣運動而放棄博士學業，在美國度過二十一個年頭的流亡歲月。
《科學月刊》創刊號採用了學長提出的大氣圈意象作為封面，又在第二期刊登了他題為〈溫室效應和大氣圈效應〉的文章。半個多世紀前，一位研究生寫下的這篇科普文章；今天已成為全世界共同面對的重要課題，而當年那位研究生，今天站上校友會講台，把五十多年來累積的研究、思索與對社會的關懷，分享給在場認真聆聽的同學。好似有一股力量force把學長帶回這個現場，跨半世紀的時與空，回應五十六年前的關懷。
第三件事，就是今天的主題了。學長共帶來四個題綱：basic science, controversies, mitigation and adaptation, ENSO(聖嬰現象)。雖然都是嚴肅的課題，但學長深入淺出，而且不時夾雜著輕鬆風趣的軼事。
在氣候爭議上，學長提醒大家，全球暖化並非單一因素造成。除了 CO₂ 排放，大氣與海洋自然變化也扮演角色；空氣污染中的懸浮微粒甚至具有降溫效果，因此中國改善空污後，也可能影響全球升溫速度。這些複雜議題常被簡化成氣候變遷吹哨者Climate alarmists 與氣候變遷否認者 Climate deniers 的政治標籤。學長也分享許多科學與政治交織的趣聞，讓嚴肅議題多了一份幽默。
學長指出暖化的核心問題是「水」。氣溫升高後，大氣可容納更多水氣，潮濕地區可能面臨更強烈暴雨，乾旱地區則可能遭遇更頻繁、更持久的乾旱。颱風平均強度會增強，但次數基本不會增加。海平面上升也因地而異，舊金山二十五年來上升一吋，美國東岸卻已上升七吋，未來差距還會持續擴大。
學長講了好幾個治沙難題的有趣故事。其中之一是青海塔拉灘為了發展綠能，佈建了大面積的光伏，須用大量清水沖洗。光伏遮蔽了陽光降低地表溫度，加上水，使得戈壁長草。草長過高又阻擾到光伏模板，只好引進羊群來控制，結果牧羊和發電的經濟收益遠遠超過運水的成本，整片沙地又自動綠化成功。此時大家聽得津津有味，為成功治沙創造雙贏喝采。學長分享寫過的對聯：「四十載艱辛摸索疑無路，減碳中柳暗花明又一村。」
然而，南疆塔克拉瑪干沙漠的未來則充滿挑戰。鎖邊工程與沙漠鐵路令人驚嘆，但周邊冰川因暖化持續退縮，未來農業與經濟仍必須轉型。學長也以另一副對聯寫道：「塔克拉瑪干鎖邊盡人事，昆崙山冰川退守問天機。」
加州雖無冰川，卻同樣面臨威脅。Sierra Nevada 山區積雪減少、融雪提前，使原本如天然水庫般調節水源的功能下降。中央山谷central valley長期依賴融雪灌溉的農業模式，未來可能面臨水資源不穩、農業調整甚至部分退耕的困境。最後，學長談到近期受到關注的 El Niño(聖嬰現象)，雖然可能為加州帶來較多降雨，但氣候預測仍存在高度不確定性，未來高空噴射氣流的變化將是重要觀察指標。
除了科學內容，學長也談到能源政策、人類活動，以及氣候變化對文明發展的影響。例如匈奴西遷、又如樓蘭古國被沙漠吞噬，歷史提醒我們：人類可以努力，但面對自然力量force，仍需學習理解與順應。
Q&A 時間，聽眾踴躍提問，直到何秀婷會長不得不宣布時間已到，才結束這場麗美前前前會長所稱「cozy，但知性的下午」。會後，前任駐舊金山科技組周仁章組長感嘆：「今天的知識密度太高了，要回去慢慢消化。」
走出會場，我腦海裡仍不斷回想演講中的許多片段。從全球暖化、海面上升、沙漠化，到冰川退縮、聖嬰，人向天爭取資源等，內容豐富而緊湊。我已經被一張又一張投影片淹沒，但淹不過學長一路流露出的思考與關懷。回想演講開始前，我們兩人杵在會場門外等人來開門；門打開後學長從三張投影片開展氣候變化中他的人生故事與科學專業；我打開筆電勤作筆記。記下來的，是一場關於氣候變化的演講內容，寫不出來的是一位台大校友，五十多年來始終不變的初心：「以科學理解自然，以關懷回應世界。」如同呈現給大家的演講花絮之花開花落結子再長，我們終究是大自然之子，氣候變化永存於大自然的力量(force)中。
科學當中也有故事，歡迎上 YouTube 聆聽這場「氣候變化與全球暖化之科學與故事」的分享：
附註
1. 這一小節作者為：台大1985年外文系畢業的吳毓瑩校友。
2. 張博士原文所提供「超連結」已被另一則相關報導取代。
編後記：
這篇文章是張智北博士在《保釣論壇》，回應本欄上一篇胡承渝博士的大作；就承渝兄觀點做了進一步的分析和申論。分節、各節子標題、以及部分文字和標點修改，則是我做的編輯工作。
本文於 修改第 3 次
|
|
「全球暖化」對中國的影響 -- 胡承渝
|
|
|
推薦1 |
|
|
|
全球暖化
胡承渝，08/30/26
十多年前，一部柴靜訪問人大常委會副委員長丁仲禮院士，討論全球暖化和減碳議題的視頻，引起大衆注意。因為丁院士一句「中國人是不是人？」，得到很多自認是「民族主義」者的認同，柴靜也被攻擊為「漢奸」。
丁院士在視頻中，否認全球暖化是人類活動造成，並說即使有全球暖化，對中國反而有益處。
最近中國、尼泊爾邊境因氣候暖化，造成冰川崩潰，而產生巨大的泥石流，失蹤人數在三千以上，不知自認是「民族主義者」而支持丁院士的人有何感想？
也許他們會説，這只發生於高山峻嶺，與普通人無關。
清華大學 2025年的研究報告，2024年是有氣象記錄以來最熱的一年。中國氣溫較歷史平均水平高出 1.01°C。與熱浪暴露相關的死亡數字超過 2.01 萬例，比歷史基綫平均水平高 1.7 倍；最高的城市是蘇州，其次是上海、無錫、南京和杭州。這總不能說與普通人無關了。
今年 8月 17日《柳葉刀》(臺灣譯《刺胳針》)有一篇論文 “Exceeding human heat tolerance in a warming, ageing world: a global projection modelling study“：結論是：
1) 「我們的研究結果表明，考慮到年齡分層脆弱性，難以忍受的高溫將在更大的範圍內持續更長時間，影響的人數將遠遠超過先前的估計。」
2) 以地域分，「人口稠密的炎熱潮濕地區，例如南亞(尤其是印度-恆河平原)、中國東部和西非，已成為更主要的暴露熱點地區。」
3) 「印度、中國、巴基斯坦和孟加拉共有14.8億暴露人口，佔全球20.3億暴露人口總數的72.6%。」
全球暖化真像丁院士講的，對中國好嗎？
全球暖化是一科學議題，是不是事實，對人類好不好，要從科學上尋找證據。不能以自認的「民族主義」否認科學的研究結果。
編後記：
這篇文章是胡承渝博士在《保釣論壇》上發表的大作；版面略作編排，意旨未改。
本文於 修改第 1 次
|
|
冷卻地球計畫 -- Corbin Hiar
|
|
|
推薦1 |
|
|
|
A closely guarded plan to cool Earth is revealed
A geoengineering company would use tiny specks of silica to block sun rays — and make billions of dollars.
Corbin Hiar, 05/15/26
Sun, Global Warming, Heat wave hot sun, Climate Change, Burning forest
(chuchart duangdaw via Getty Images) 示意照片
A company that aims to make billions of dollars by cooling the Earth has lifted the veil of secrecy that until now has hidden its plans for preventing sunlight from overheating the planet.
It hinges on aerosol particles that are 125 times smaller than the tiniest grains of sand.
Stardust Solutions has raised $75 million since 2023 from investors who are betting that global warming could get so out of control that governments might decide to pay the Israeli-U.S. startup to spray millions of tons of sunlight-reflecting aerosols into the stratosphere. Its plans were so guarded that it required scientists to sign nondisclosure agreements before they could study its potentially planet-altering technologies.
On Thursday, the company revealed the makeup of its proprietary particles. They are made of what's known as amorphous silica and are 0.5 microns in size — only visible with a microscope. The startup also shared information about the systems it could use to disperse the spherical silica particles some 11 miles above the ground and monitor them as they fall back to the Earth.
"Our premise from the start was that the only way sunlight reflection technology would be considered by governments is if we provided robust scientifically-based solutions to all the challenges and concerns and proved it to be safe, practical, and controllable," Stardust CEO Yanai Yedvab said in a statement. "That is the mission we took upon ourselves, and the details we are releasing today represent a major step toward that goal."
The company is a leader in solar geoengineering — the hypothetical pursuit of altering clouds or changing other characteristics of the atmosphere in ways that would interrupt sun rays before they hit the Earth. Other ideas envision building massive sun shades in space or creating bubbly mixtures of reflective sea foam to limit the amount of heat absorbed by the oceans.
Geoengineering is unlike other responses to climate change because, while it can theoretically reduce warming, it does not address the root cause: the burning of fossil fuels. That means the world would be effectively hooked on solar geoengineering until nations reduce their use of oil, gas and coal to safe levels and then remove excess climate pollution from the air and seas.
Stardust's revelations came as President Donald Trump and Chinese President Xi Jinping held a rare bilateral summit in Beijing and after record-breaking heat and drought this year have triggered historic wildfires in the U.S. and Southeast Asia. While climate change and geoengineering was not on summit agenda, both countries' support — or tacit acceptance — would likely be necessary for Stardust to deploy its particles and repay its investors, according to analysts.
"Just given their size, they're key players in all this," said Erin Sikorsky, who served on the National Intelligence Council during the Obama administration, referring to the U.S. and China. She now leads the Center for Climate and Security, a think tank. "They could stop somebody from doing this if they wanted to. And so that matters to a company like Stardust."
Yedvab, the company's CEO, said in an email that the timing of the release was "not connected" to the U.S.-China summit.
The new details about Stardust's silica particles and other systems were disclosed in six academic papers that it posted online. Most of the papers were written with experts at leading universities, but they have not yet undergone peer review — a critical step in the scientific publishing process where other experts review and comment on the findings.
The company is currently seeking patents for its particles and other technologies — a key component of its business strategy. Stardust said it is also submitting the papers to scientific journals.
Stardust is developing two types of amorphous silica-based particles. One is "fully bio-safe, manufacturable at scale today, and at a very advanced stage of validation," according to a summary of the research. Another similarly sized version of the silica particle includes a calcium carbonate core that it said would more effectively block solar radiation.
"Both designs are intentionally engineered to recycle into existing natural cycles after they settle to the ground," the summary said.
Amorphous silica has a different atomic structure than crystalline silica, the reactive, hazardous dust released by cutting or crushing certain types of rocks. Stardust is not using crystalline silica in its process. Amorphous silica isn't known to pose a risk to humans at low doses, according to the World Health Organization's cancer research agency.
Stardust has previously pitched investors on a plan for "global full-scale deployment" as soon as 2035, according to an investor deck previously reported by POLITICO Magazine. At that point, the company's expected revenues would be around $1.5 billion annually, the deck said. Stardust has said the presentation from 2023 no longer reflects its current thinking.
Some scientists remain wary of Stardust and other solar geoengineering companies. They fear that the technology could be misused at a time when international cooperation is fraying.
"This announcement is a clear example of why self governance led by for-profit entities does not work," said Shuchi Talati, the executive director of the Alliance for Just Deliberation on Solar Geoengineering, a nonprofit that seeks to include marginalized countries and communities in debates over sunlight-reflecting technologies.
Stardust, she said, "cannot create their own principles and then applaud themselves for following them. They cannot define safety according to their own standards and then self-certify that they meet them. The field requires coordinated, legitimate, and independent research governance."
Talati's alliance is working with the Natural Resources Defense Council, the American Geophysical Union and other groups to set standards for solar geoengineering research and development.
“It rarely works out well when those who develop globally significant technology are also in charge of governing it," added Hannah Safford, a White House climate policy adviser during the Biden administration.
“In the United States, government has shown more interest in banning climate science than in thoughtfully governing emerging technology,” said Safford, who is now at the Federation of American Scientists, a think tank. “That leaves the door wide open for other countries, companies, and individuals to run out in front — and we might not like the choices they make.”
本文於 修改第 1 次
|
|
生態悲觀論與冷酷無情政策 – Matt Ridley
|
|
|
推薦1 |
|
|
|
請參考：
Paul Ehrlich, often called alarmist for dire warnings about human harms to the Earth, believed scientists had a responsibility to speak out
我讀過瑞德利的《基因組合：有23篇章的物種自傳》，和艾爾立克的《人類本性：基因、文化、與人類前景》；下文標題自然引起我的好奇和興趣。讀過之後，再度了解到：「學者」中也不乏偏執狂和顢頇之徒。
Ridley: Ehrlich's anti-human legacy
From the original Rational Optimist
Matt Ridley, 03/19/26
The butterfly biologist turned rock-star eco-pessimist, Paul Ehrlich has died at the age of 93. That in itself is remarkable because in 1970 he forecast that within the coming decade “100-200 million people per year will be starving to death” and “by 1985 enough millions will have died to reduce the earth’s population to some acceptable level, like 1.5 billion people”. Furthermore, by 1980 the life expectancy of the average American would have fallen 42 years as a result of cancer caused by pesticides.
Yet he not only lived more than 50 years longer than 42; he lived to be one of more than 8 billion people in a world where global life expectancy has increased at the average rate of seven hours per day since he forecast it would collapse. Meanwhile, famine has all but gone extinct, with death rates from mass starvation down to a tiny fraction of what they were in the 1960s. Here are the astounding numbers: in the 1960s, 29.7 million people out of a population of 3 billion died in famines that killed more than 100,000 people each. In the 2010s, 1.1 million out of a population of more than 8 billion died in such episodes: a decline of 99% in the death rate.
Source: Our World in Data 飢荒導致死亡人數依地區和年份統計圖
In short, Ehrlich was wrong. Not, as the New York Times said in its obituary this week, “premature”, but radically, completely, spectacularly wrong. He was wrong as soon as he put pen to paper and went on being wrong for decades afterwards. He shot to fame with a best-selling book in 1968, The Population Bomb, whose prologue dismissed all hope for humankind: “The battle to feed all of humanity is over. In the 1970s hundreds of millions of people will starve to death in spite of any crash programs embarked upon now. At this late date nothing can prevent a substantial increase in the world death rate.”
Yet something did prevent that. Even as he wrote these words, the world’s population growth rate was falling. New strains of wheat and rice developed by agronomists like Norman Borlaug were starting to transform the productivity of agriculture and India was on the way to banishing famine and becoming a food exporter within a few short years. The amount of food available has increased faster than population on every continent over the last 60 years even as the land area devoted to farming has begun to fall. As so often with environmental pessimism, Ehrlich’s warning was already out of date when it was made.
Source: Our World in Data人口增長和食物供應增長比較統計圖
For the rest of his life Ehrlich remained adamant that he was not so much wrong as…right. In 2008 he was still predicting “an unhappy increase in the death rate”. In 2023 he tweeted plaintively: “If I’m always wrong so is science, since my work is always peer-reviewed, including the POPULATION BOMB and I’ve gotten virtually every scientific honor. Sure I’ve made some mistakes, but no basic ones.” He was indeed laden with honors when he died: including a MacArthur “genius” award in 1990 and honorary membership of London’s Royal Society in 2012 - despite forecasting in 1970 that “If I were a gambler, I would take even money that England will not exist in the year 2000.”
Getting things wrong is clearly very rewarding. But his words had consequences. For many people, the misanthropy and cruelty of his political recommendations were less forgivable than his failed forecasts. His book began with an evening in Delhi when he found the press of people overwhelming. “People eating, people washing, people sleeping. People visiting, arguing and screaming. People thrusting their hands through the taxi window, begging. People defecating and urinating.” The answer to his culture shock, he argued, was coerced, compulsory population control. “The operation will demand many brutal and heartless decisions. The pain may be intense.”
Food aid to India should be made conditional on forcible sterilisation of all those who had three or more children: “coercion in a good cause”. Ehrlich was “astounded” that libertarians objected when the American government took up his suggestion. In 1975 Indira Gandhi was refused World Bank loans unless she began sterilising people. Her son Sanjay obliged, making permits, licences, rations and even housing applications conditional on sterilisation. Eight million people were sterilised. Yet one of the greatest causes of the falling birth rate in the world over the past half century has been kindness, not cruelty: the prevention of child mortality. When mothers can be confident of their children surviving, they plan smaller families.
For Americans, too, Ehrlich recommended coercion and control. In an interview in 1970 he said that television programs should be ordered by the federal government to show large families always in a “negative light”. Commercials should relentlessly shame such people. If that did not work, the government should give women a “bonus for not having babies” or “change the tax structure” to punish the fertile, and if necessary, “legislate the size of the family” and “throw you in jail if you have too many” children.
Immensely influential, Ehrlich set the dirigiste tone for the nascent environmental movement, which saw people as the problem, economic growth as a crime and coercion as necessary. As Ehrlich’s attention switched to the running out of resources in the late 1970s, the economist Julian Simon called his bluff. In 1980 he offered Ehrlich a bet: that the price of a $1,000 basket of five metals (to be chosen by Ehrlich) would fall in real terms by 1990 because human ingenuity meant the world was getting better at finding such resources. The loser was to pay the difference in the price of the basket.
Ehrlich rushed to accept Simon’s “astonishing offer before other greedy people jump in” though he later dissembled that he had been “goaded” into the bet. He chose chromium, copper, nickel, tin and tungsten, with $200 invested in each. But when 1990 came round it was Ehrlich who owed Simon $576.07, all five having fallen in price. Ehrlich would have lost even without taking inflation into account. Grudgingly he made his wife write out the check, before delivering a speech in which he said of Simon, “the one thing we’ll never run out of is imbeciles”.
On my bookshelf stands the Julian Simon award, which I won in 2012 and which is made of the five metals. Simon, who was just three months older than Ehrlich, died at the age of 66 in 1998, far too young. He was never a celebrity.
A version of this article originally appeared in The Free Press.
Subscribe to Rational Optimist Society
Launched a year ago
Making rational optimism cool
本文於 修改第 4 次
|
|
伊朗的水荒危機--Adi Wolfson
|
|
|
推薦1 |
|
|
|
請參考：
* Iran’s Water Crisis Is a Warning to Other Countries
* 當共產主義成為唯一的選項 -- Slavoj Žižek(該欄2025/12/15)
The greatest crisis facing Iranians today
From extreme drought and water depletion to toxic air pollution, Iran faces an unprecedented ecological crisis shaking its natural, economic and social systems; as hardships mount, could public unrest against the regime be on the horizon?
Prof. Adi Wolfson, 12/13/25
The dramatic weather swings of recent weeks—from unseasonal heatwaves to flooding—are a stark reminder that the climate crisis is no longer a future threat, but a present reality.
Around the world, shifting climate patterns are reshaping lives, and few places illustrate the severity more clearly than Iran, where worsening drought, widespread power and water outages and hazardous air pollution are capturing international attention.
Iran’s deepening ecological crisis stems from a combination of natural climate shifts and years of poor infrastructure and resource mismanagement. The country is warming at nearly twice the global average, with a 2°C rise in mean temperatures since the 1950s.
This has dramatically altered rainfall patterns: over the past 20 years, precipitation has dropped by about 20%. In the past two years, the decrease reached 40%, and since the start of the 2025 rainy season in late September, rainfall is down by a staggering 90%.
Meanwhile, soaring temperatures are accelerating evaporation from natural and man-made reservoirs, as well as from soil and vegetation. Compounding these changes are years of reckless and even criminally negligent water management by Iranian authorities.
Iran’s population has grown by roughly 30% in the last two decades, alongside rapid urbanization and industrial expansion, all increasing demand for water. The agricultural sector, heavily subsidized by the government, has encouraged inefficient water use. As a result, aquifers have been over-pumped, surface water reservoirs have dried up, water quality has deteriorated and ecosystems have collapsed.
The depletion of Iran’s major water reserves has now reached critical levels, with key reservoirs serving homes, factories and farms running dry. Water cuts are now routine, disrupting daily life, reducing agricultural output and prompting food imports and price hikes. For Iran’s already fragile economy, the impact has been devastating.
The water crisis has also triggered an energy crisis. Hydroelectric power output has plummeted due to depleted dams, and cooling systems at fossil-fuel power plants have been affected. Electricity blackouts have become frequent and prolonged, hampering everyday life and disrupting industries, including oil production and refining. The strain on public health has grown, with rising illness and mortality linked to the crisis.
Groundwater depletion has caused saltwater intrusion from deeper layers, further salinizing land and damaging plant and animal life. The disappearance of aquifers has altered soil structures, leading to significant land subsidence—measured at up to 25 centimeters annually in western Tehran.
These changes have intensified air pollution. Dry, brittle soil in parched regions now turns to dust and salt, easily carried by windstorms. In recent weeks, these particles have triggered extreme air pollution across Iran. In Tehran—already plagued by smog from heavy traffic and petrochemical industries—air quality indices have reached some of the highest, most hazardous levels in the world.
The mullah government has blamed climate change and international sanctions for the catastrophic state of the country’s water and energy systems. Regime officials have even warned that unless divine intervention comes soon, mass evacuations—including from the capital of Tehran—may become necessary.
Yet forecasts suggest that Iran’s ecological emergency will worsen, threatening its economy, food security and very way of life. The growing risk of climate-driven displacement raises the question: could this crisis eventually spark a popular uprising? Time will tell.
Prof. Adi Wolfson is head of the Master's Program in Green Engineering at Sami Shamoon College of Engineering.
本文於 修改第 2 次
|
|
地球暖化與生物「大滅絕」的關係 - Laura Paddison
|
|
|
推薦1 |
|
|
|
請參考：地球五次物種大量滅絕的原因
The ‘Great Dying’ wiped out 90% of life, then came 5 million years of lethal heat. New fossils explain why
Laura Paddison, CNN, 07/02/25
A new study uses a vast trove of fossils to better understand what happened after the "Great Dying" mass extinction event. - Dr. Zhen Xu 請至原網頁觀看照片
Around 252 million years ago, life on Earth suffered its most catastrophic blow to date: a mass extinction event known as the “Great Dying” that wiped out around 90% of life.
What followed has long puzzled scientists. The planet became lethally hot and remained so for 5 million years.
A team of international researchers say they have now figured out why using a vast trove of fossils — and it all revolves around tropical forests.
Their findings, published Wednesday in the journal Nature Communications, may help solve a mystery, but they also spell out a dire warning for the future as humans continue to heat up the planet by burning fossil fuels.
The Great Dying was the worst of the five mass extinction events that have punctuated Earth’s history, and it marked the end of the Permian geological period.
It has been attributed to a period of volcanic activity in a region known as the Siberian Traps, which released huge amounts of carbon and other planet-heating gases into the atmosphere, causing intense global warming. Enormous numbers of marine and land-based plants and animals died, ecosystems collapsed and oceans acidified.
What has been less clear, however, is why it got so hot and why “super greenhouse” conditions persisted for so long, even after volcanic activity ceased.
“The level of warming is far beyond any other event,” said Zhen Xu, a study author and a research fellow at the School of Earth and Environment at the University of Leeds.
Some theories revolve around the ocean and the idea that extreme heat wiped out carbon-absorbing plankton, or changed the ocean’s chemical composition to make it less effective at storing carbon.
But scientists from the University of Leeds in England and the China University of Geosciences thought the answer may lie in a climate tipping point: the collapse of tropical forests.
The Great Dying extinction event is unique “because it’s the only one in which the plants all die off,” said Benjamin Mills, a study author and a professor of Earth system evolution at the University of Leeds.
To test the theory, they used an archive of fossil data in China that has been put together over decades by three generations of Chinese geologists.
A complicated broad leaf seed fern from a pre-extinction South China rainforest. - Dr. Zhen Xu 請至原網頁觀看照片
A post-extinction plant called a lycopod sporophyll. - Dr. Zhen Xu 請至原網頁觀看照片
They analyzed the fossils and rock formations to get clues about climate conditions in the past, allowing them to reconstruct maps of plants and trees living on each part of the planet before, during and after the extinction event. “Nobody’s ever made maps like these before,” Mills told CNN.
The results confirmed their hypothesis, showing that the loss of vegetation during the mass extinction event significantly reduced the planet’s ability to store carbon, meaning very high levels remained in the atmosphere.
Forests are a vital climate buffer as they suck up and store planet-heating carbon. They also play a crucial role in “silicate weathering,” a chemical process involving rocks and rainwater — a key way of removing carbon from the atmosphere. Tree and plant roots help this process by breaking up rock and allowing fresh water and air to reach it.
Once the forests die, “you’re changing the carbon cycle,” Mills said, referring to the way carbon moves around the Earth, between the atmosphere, land, oceans and living organisms.
Michael Benton, a professor of paleontology at the University of Bristol, who was not involved in the study, said the research shows “the absence of forests really impacts the regular oxygen-carbon cycles and suppresses carbon burial and so high levels of CO2 remain in the atmosphere over prolonged periods,” he told CNN.
Another post-extinction lycopod. - Dr. Zhen Xu 請至原網頁觀看照片
It highlights “a threshold effect,” he added, where the loss of forests becomes “irreversible on ecological time scales.” Global politics currently revolve around the idea that if carbon dioxide levels can be controlled, damage can be reversed. “But at the threshold, it then becomes hard for life to recover,” Benton said.
This is a key takeaway from the study, Mills said. It shows what might happen if rapid global warming causes the planet’s rainforests to collapse in the future — a tipping point scientists are very concerned about.
Even if humans stop pumping out planet-heating pollution altogether, the Earth may not cool. In fact, warming could accelerate, he said.
There is a sliver of hope: The rainforests that currently carpet the tropics may be more resilient to high temperatures than those that existed before the Great Dying. This is the question the scientists are tackling next.
This study is still a warning, Mills said. “There is a tipping point there. If you warm tropical forests too much, then we have a very good record of what happens. And it’s extremely bad.”
For more CNN news and newsletters create an account at CNN.com
本文於 修改第 2 次
|
|
全球人口估計大烏龍？ -- D. Orf
|
|
|
推薦1 |
|
|
|
Oops, Scientists May Have Severely Miscalculated How Many Humans Are on Earth
We’ve gotta start counting from 1 again...
Darren Orf, 03/19/25
"Hearst Magazines and Yahoo may earn commission or revenue on some items through these links."
* While most estimates place the current human population at around 8.2 billion, a new study suggests we might be vastly underrepresenting rural areas.
* By analyzing 300 rural dam projects across 35 countries, researchers from Aalto University in Finland found discrepancies among these independent population counts and other population data gathered between 1975 and 2010.
* Such underreporting could have consequences in terms of resource allocation within a country, but other experts remain skeptical that decades of population counting could be off by such a wide margin.
Homo sapiens is the most successful mammalian species in Earth history, and it’s not even close. The species thrives on nearly every continent, in a variety of adverse conditions, and outnumbers the second-place contender—the rat—by at least a cool billion. However, a new study suggests that the impressive nature of humanity’s proliferation may have been vastly underreported.
Most estimates place Earth’s human population at around 8.2 billion, but Josias Láng-Ritter—a postdoctoral researcher at Aalto University in Finland and lead author of the study published in the journal Nature Communications—claims that these estimates could be underrepresenting rural areas by a significant margin.
“We were surprised to find that the actual population living in rural areas is much higher than the global population data indicates—depending on the dataset, rural populations have been underestimated by between 53 percent to 84 percent over the period studied,” Láng-Ritter said in a press statement. “The results are remarkable, as these datasets have been used in thousands of studies and extensively support decision-making, yet their accuracy has not been systematically evaluated.”
How exactly do you test the accuracy of global datasets used to derive population totals in the first place? Well, with a background in water resource management, Láng-Ritter looked at a different kind of population data gathered from rural dam projects—300 such projects across 35 countries, to be precise. This data focused on the years 1975 to 2010, and these population tallies provided a significant dataset to check against other population totals calculated by organizations like WorldPop, GWP, GRUMP, LandScan, and GHS-POP (which were also analyzed in this study).
“When dams are built, large areas are flooded and people need to be relocated,” Láng-Ritter said in a press statement. “The relocated population is usually counted precisely because dam companies pay compensation to those affected. Unlike global population datasets, such local impact statements provide comprehensive, on-the-ground population counts that are not skewed by administrative boundaries. We then combined these with spatial information from satellite imagery.”
Part of this discrepancy likely stems from the fact that many countries don’t have the resources for precise data collection, and difficulty traveling to far flung rural areas only exacerbates census-counting discrepancies. A widespread underrepresentation of rural populations across the world could have profound impacts on those communities, as censuses are central to figuring out how to divvy up resources.
However, not everyone is convinced by this research. Stuart Gietel-Basten from the Hong Kong University of Science and Technology told New Scientist that while increased investment in rural population data collection would be beneficial, the idea that Earth could contain a few billion more human inhabitants that we thought is extremely unlikely. “If we really are undercounting by that massive amount, it’s a massive news story and goes against all the years of thousands of other datasets.”
When trying to count such a massive population, a few hundred or maybe even a few thousand may slip through the cracks. But a few million or even billion would upend our understanding of human occupation on this planet. Scientists will need a bit more evidence before rethinking decades of dataset research.
本文於 修改第 1 次
|
|
地球生態四大支柱面臨崩塌危機 -- Darren Orf
|
|
|
推薦1 |
|
|
|
There Are 4 Pillars of Stability for Life on Earth. Scientists Say They're Close to Collapse.
What do you do when your planet’s essential equilibrium is teetering on the edge of disaster? Asking for a friend.
Darren Orf, 08/16/24
"Hearst Magazines and Yahoo may earn commission or revenue on some items through these links."
* Scientists have discerned certain systems that, if they collapse, would spell doom for humanity’s future on Earth.
* A new study analyzes the possibility of such a collapse by creating models surrounding four of these pillars: the West Antarctic Ice Sheet, the Greenland Ice Sheet, Amazon Rainforest, and the Atlantic Meridional Overturning Circulation (AMOC).
* The study finds that such a collapse is concerningly likely under current climate policies, and that probability reportedly increases dramatically every tenth of a degree Celsius we blow past our 1.5-degree goal.
If our exploration of the cosmos has taught us one thing, it’s that creating life isn’t easy. First, you need the right chemical conditions (and potentially some cloud-to-ground volcanic lightning) to get things going. But to create complex, intelligent organisms, you need a planet whose climate is relatively stable—allowing for a particularly big-brained species to grow into cultures, then into countries, and then (hopefully) into a planet-wide, peace-loving collective a la Star Trek.
But before we can hop into our Starship Enterprise and explore the galaxy, humanity—as well as every other living thing on this planet—needs climatic stability. And sadly, that’s something the “big-brained” species on Earth is doing a pretty poor job of managing.
To emphasize what a bang-up job we’re doing, scientists have previously identified several tipping points (not to be confused with planetary boundaries, which to put it mildly, are also bad news) that pertain to the certain global climate systems that have kept things running smoothly throughout history.
Four of those pillars of stability are the West Antarctic Ice Sheet, the Greenland Ice Sheet, Amazon Rainforest, and the Atlantic Meridional Overturning Circulation (AMOC)—the ocean current system that keeps Europe several degrees warmer than it otherwise would be. A new study published earlier this month in the journal Nature focused on these elements, and discerned the probabilities of their collapse and the impact on the future habitability of the planet. The results were... not good.
The paper reads:
“Under current emission trajectories, temporarily overshooting the Paris global warming limit of 1.5 °C is a distinct possibility. Permanently exceeding this limit would substantially increase the probability of triggering climate tipping elements. Achieving and maintaining at least net zero greenhouse gas emissions by 2100 is paramount to minimize tipping risk in the long term.”
The study creates a new set of models that treats each of these systems like the pillars they are—that is, if one falls, the rest soon follow suit due to the interconnected nature of each system. According to the paper, “current climate policies until 2100 may lead to high tipping risks,” and that even includes the scenario in which humans get their act together and keep temperature rise below the 1.5 degree Celsius threshold by 2300. In other words, many of these tipping points represent a “point of no return.” Once the tipping point is reached, there is no going back.
The researchers mark the tipping possibility at 45 percent until 2300, and a whopping 76 percent in the long term. Additionally, the study finds that there would be a non-linear acceleration of these percentages for every 0.1 degree Celsius that overshoots the current climate goals. Each tenth of a degree beyond the 2 degree Celsius threshold, for example, adds an additional 3 percent tipping risk, according to the study. The only way to curtail this long-term disaster? Achieving net zero carbon emissions by 2100.
A recent article published by The New York Times detailed how humanity was already entering many threshold ranges for certain tipping points—including the mass death of coral reefs, the abrupt thawing of permafrost, the collapse of the Greenland Ice Sheet, and the break up of West Antarctic Ice. The outlook is far from rosy, and while it’s too late to escape this period of anthropogenic global warming unscathed (there are already millions of climate refugees), we have the tools, the science, and the know-how to start treating this climate crisis as the existential threat that it is.
Otherwise, as these new models depressingly predict, any sort of galaxy-traipsing utopian vision could be forever out of our reach.
You Might Also Like
* The Do’s and Don’ts of Using Painter’s Tape
* The Best Portable BBQ Grills for Cooking Anywhere
* Can a Smart Watch Prolong Your Life?
本文於 修改第 1 次
|
|
人口減少可能是福不是禍 ---- Kirsten Stade
|
|
|
推薦1 |
|
|
|
下文強調人口過多對人類、地球生態、和人類以外其它生物所帶來的負面壓力與後果；值得細讀和深思；請多多利用文中的超連結。此外，拙作強調「生活方式」和「生態保護」兩者間的相關性(該欄2024/05/11)，可和下文類似觀點參照。
'Worrying' Population Declines Are Actually A Hopeful Sign
Kirsten Stade, 06/12/24
Human population is in the news, but not for the reasons we are used to. At one time, our growing population was seen as central to wildlife extinctions, resource depletion, pollution and environmental destruction. But today, we are more likely to hear that there are too few of us, not too many. As women across the world have gained greater reproductive choice, birth rates have declined.
This is a positive development in large part due to a decline in teen pregnancy, but you would never know it from news coverage of the topic that ranges from anxious to apocalyptic. The birth rate "crisis," we are told, will have dire consequences for our economy and especially for seniors. Lost in the conversation are the many positive aspects of an aging society, which is the result of people living healthier and longer lives, and common-sense realities like reduced needs for infrastructure and lower ecological impacts. Also lost is the fact that our population still grows by 80 million people every year, from places in the world where women and girls lack reproductive choice and face powerful pronatalist pressures, whether to carry on a family line, grow a religious denomination, or fuel economic growth with more consumers and cheap labor.
And the consequences are dire. Among them is global warming, which the Intergovernmental Panel on Climate Change warns is driven by both population and economic growth. In fact, increased emissions from population growth have canceled more than three quarters of the emissions saved through energy efficiency and renewables over the past three decades.
Yet, no matter how well documented the link between population and climate, lowering our population is conspicuously absent from the conversation on solutions. Instead, the focus is on technology that will supposedly allow our entire growing population to enjoy the energy-intensive lifestyles now enjoyed by the rich, and with no climate impacts.
But "green" technology is not the solution it is cracked up to be. Its buildout to the degree needed to power a growing population at a decent standard of living would itself require a staggering investment in fossil fuels. It will also require massive mining operations. Batteries for electric vehicles use lithium from places that cannot spare the enormous quantities of water required for its extraction, places like parts of Nevada sacred to Native Americans and the deserts of Bolivia. Other mining for lithium, as well as for copper, nickel, and cobalt needed for wind turbines and electric cars, takes place on the backs of low-wage workers, many of them children, in Africa where it is driving destruction of rainforests critical to the survival of great apes. The next frontier for mining these minerals is the deep seabed, where extraction threatens endemic and undiscovered species. And the minerals are destined for renewable energy infrastructure and transmission capacity with impacts of its own: it requires 10 times the land area as fossil fuel plants for the same amount of energy generated.
And of course, it bears remembering that electricity is only 20 percent of global energy demand—the rest is devoured by air travel, shipping, steel production, and other sectors whose "decarbonization" is difficult to imagine.
In short, providing even "green" energy for 8 billion and counting will have ecological impacts that are seldom discussed. The impacts of feeding that many are even more chilling. At our current population and rates of consumption, agriculture takes up 40 percent of Earth's ice-free land area. Primarily through deforestation and habitat destruction, it is the leading threat to 86 percent of species at risk of extinction and consumes 70 percent of the planet's freshwater. These impacts are not just from industrial agriculture; globally, subsistence agriculture is responsible for 33 percent of deforestation while large-scale commercial agriculture drives 40 percent.
It is difficult to imagine how food production can expand to feed the additional 2 billion people projected by 2100 without further devastating Earth's biophysical systems. The rapidly growing global middle class and its preference for meat-heavy diets has dire ecological implications, as animal agriculture uses the vast majority of farmland and is responsible for 60 percent of the greenhouse gas emissions from agriculture.
The extraordinary ecological impacts of expanding animal agriculture are not surprising when you consider its scope: in the past 50 years, as the world's population has more than doubled, the number of land animals slaughtered globally has increased from 12 billion to 80 billion. Today, of the total biomass of terrestrial vertebrate species, 60 percent is livestock, 36 percent is humans, and 4 percent is all living wild mammals, birds, reptiles, and amphibians.
While the mass of living creatures is dominated by humans and our livestock, the sheer mass of human-made things, from cellphones to interstate highway systems, has exceeded the weight of all living things and grows by 30 billion tons annually. One of the side effects of our massive technosphere is pollution on a scale that threatens what living biomass remains. Pollution can be difficult to ignore, like the great Pacific garbage patch whose area is twice the size of Texas and which is largely made up of discarded fishing gear, or the toxic air pollution that jeopardizes human health in densely populated cities like New Delhi. Or it can be more insidious like the agricultural nutrient runoff causing 78 percent of global ocean and freshwater eutrophication—degradation of freshwater that is becoming perilously scarce due largely to animal agriculture, which uses 1,800 gallons of water to produce one pound of beef.
When global heating threatens to push billions outside of temperature limits compatible with human life, it is no time to panic that we are adding fewer to those billions. In fact, declining birth rates should be cause for celebration for all they signify about gender equality, children's wellbeing, and easing our burden on Earth. Rather than lamenting low birth rates and strategizing about pronatalist coercion that might reverse them, we should embrace and adapt to this positive trend and celebrate what it means for our planetary future.
Kirsten Stade is a conservation biologist and communications manager of the NGO Population Balance.
The views expressed in this article are the writer's own.
本文於 修改第 2 次
|
|
|
本城市首頁
看回應文章
等級：8
