Meltdown is about melting glaciers, which cause (among other things):
- more global warming
- more sea level rise that destroys coastal communities and ecosystems
- more fresh water shortages at key moments when we need water the most
- more warming of the oceans
- more unstable and violent weather patterns
- more destruction of habitat and feeding grounds for flora and fauna
- more land shifts that can destroy current ecological stability
- and more dangerous environments that can lead to catastrophic incidents like glacier tsunamis (GLOFs).
“Meltdown“ 這本書談到冰川融化會造成的問題，包括：
- 加重全球暖化。
- 提高海平面，摧毀瀕臨海岸的社區及生態系統。
- 在最需要水的關鍵時刻更常缺水。
- 海洋變得更暖。
- 天氣型態變得更不穩定而且極端。
- 更多開花植物及動物的棲位及食物來源地區受到破壞。
- 更多土石滑動而毀及現存生態圈的穩定性。
- 形成更危險的環境導致諸如冰川海嘯等的災難事件。
Melting glaciers aren’t the original cause of our climate problems, they are a symptom of a much greater problem (global warming). But they are also a force, which in turn feeds back into the problem and makes it even worse. Scientists call this a feedback loop intensifying a tendency. Our climate is changing drastically, perhaps beyond repair. Scientists call this moment when things become unreparable, the tipping point.
冰川融化當然不是造成氣候問題的根本原因，那只是全球暖化這個更大的問題的症狀而已。但是它也是一種推力，反饋回來使得全球暖化更嚴重。科學家稱之為一種惡性循環。氣候的改變是劇烈的，或許已經無法挽回。科學家們稱事情發展到幾乎無法轉圜的關鍵時刻為轉捩點。
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CO2 emissions are responsible for about two thirds of global warming. In other words, CO2 emissions are responsible for about two thirds of the increase in planetary temperature. And while fast and aggressive CO2 mitigation is essential to combat climate change, it is not enough. Fast and aggressive mitigation is also needed for other non-CO2 emissions that are responsible for 40-45% of that net increase in planetary heat. These emissions include: black carbon, tropospheric ozone, methane, and hydrofluorocarbons (HFCs). Because these pollutants survive for relatively short times in the atmosphere (from days to a few years or decades —unlike CO2 which remains for centuries), they are considered “short-lived climate pollutants.” The super pollutants, especially black carbon and tropospheric ozone, can also be very harmful to people and environments in the areas where they are emitted.
二氧化碳排放造成全球暖化三分之二的問題。換言之，全球氣溫昇高有三分之二歸責於二氧化碳排放。固然快速而且積極防止二氧化碳排放是面對氣候變遷最主要的手段，但是那還不夠。快速而且積極防止非二氧化碳氣體的排放也很重要，那佔40%-45%全球暖化的問題。那些氣體包括碳煙、對流層臭氧、甲烷、氟氯碳化物等等。因為這些污染物在空氣中停留時間相對較短(從幾天到幾年或幾十年)，所以被認為是短期氣候污染物。其中最超級的污染物，是碳煙和對流層臭氧，在它們排放的區域對人體和周遭環境也非常有害。
Methane is a powerful greenhouse gas that is many more times harmful than CO2 for the climate. A full 60% of methane emissions are due to human activity. Black carbon (a component of soot) emitted for example by the dirty combustion of engines, the burning of wood, or from flaring in oil and gas production, is terrible for human health while also warming the atmosphere because its dark particles absorb light and melt glaciers when deposited on glacier surfaces, …Hydrofluorocarbon (or HFCs-commonly found in refrigerators or AC systems) are human-made chemicals that can be many thousands of times as harmful to the climate as CO2. Tropospheric ozone (a key component of smog) is a major air and climate pollutant, bad for people and very bad for the climate.
甲烷是溫室效應的超級氣體，對氣候的影響比二氧化碳強上數倍。足足有60%的甲烷排放是人類活動所致。碳煙(煙煤中的成份)的排放，譬如：引擎燃燒不完全、燒材、煉製油品和瓦斯加熱燃燒的過程等等，會危害人體的健康，同時會暖化空氣，因為它的黑色顆粒會吸收陽光，在落到冰川上會促使其融解……氟氯碳化物(或稱HFCs—一般見於冰箱或空調系統中) 是人造的化學物質，對氣候的影響危害數千倍於二氧化碳。對流層臭氧(煙塵的主要成份)是空氣和氣候的主要污染物，對人體不好而對氣候的影響則是很壞。
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Not addressing super pollutants and not phasing them out immediately is not an option if we are to keep to the maximum warming targets the world established in the Paris Agreement. If, for example, we delay reducing super pollutants until 2030 it will become almost impossible to keep warming to 2°C by the end of the century. A combined strategy, however, of aggressive CO2 and immediate super pollutant mitigation can avoid 0.6°C of warming by 2050 and 2.6°C by 2100.
如果我們要達到世界各國在「巴黎議定書」所設下的暖化最高目標，那麼不處理超級污染物、不將其馬上淘汰掉，就不是一個選項。譬如，假如我們延遲至2030年才減少超級污染物，那麼將不可能在這個世紀結束之前，將暖化程度保持在2°C之內。如果我們採取齊頭並進的策略，一方面積極減少二氧化碳排放，另一方面則馬上進行超級污染物的去除，那麼我們將在2050年前避免0.6°C的暖化程度，在2100前避免2.6°C。
When it comes to methane gas and black carbon, our lifestyle choices are critical if we are to reduce emissions of these pollutants and slow climate change now. First of all, it is absolutely essential to reduce our dependency on fossil fuels and change the technology that we purchase so that we can reduce these emissions. You will hear ad nauseam commercials (essentially lobbying) from the oil companies about how natural gas has made us energy independent and that natural gas is a transition fuel to clean energy. BS! Let me say that again, BS! Natural gas (methane) is not a transition fuel. It’s worse than CO2; according to the EPA, if we look at a century of impacts, methane is 25 times worse than CO2 (that is, methane traps 25 times more heat than CO2). But if we look at the short term (over a 20 year period, when methane is causing most of its damage) it’s a whopping 86 times more potent as a greenhouse gas than CO2.
至於甲烷和碳煙，如果我們要減少這些污染物的排放並減緩氣候變遷，我們生活型態的選擇至關重大。首先，絕對重要的是要減少對石化燃料的依賴，並購買先進的科技來減少相關的排放。你會從石油公司聽到令人暈頭轉向的商業廣告(主要是用來遊說)，說天然氣是怎麼讓我們減少能源的依賴，而且說天然氣是朝向乾淨能源的過渡性燃料。胡扯！讓我再駡一句，胡扯！天然氣(就是甲烷)並非過渡性燃料。依據環保署，它比二氧化碳還糟糕，如果我們評估在一世紀的時間內所造成的影響，甲烷比二氧化碳糟上25倍(也就是說甲烷的保暖效果是二氧化碳的25倍)。但是在短期(以二十年期來看，這個期間甲烷就已經造成主要的危害)，甲烷比起二氧化碳是高達86倍以上的潛在溫室效應氣體。
So when you hear those ads from the petroleum association or from oil and gas companies, talking about “clean” natural gas, just know that this is pure fabrication and paid for by the oil and gas industry. Methane is not a clean fuel. No fossil fuels are clean in any way shape or form. We need to get rid of them, and while it won’t happen overnight, it has to happen soon. Energy systems that run on natural gas have high leak rates, as do the various extraction and processing phases in the production of oil and gas. Oil and gas companies don’t like to admit it but the methane leak rates for their operations are very high, and with accidents like we saw at Aliso Canyon in California in 2015-2016, where 190,000 metric tons of natural gas leaked, uninterrupted, into the atmosphere for 5 months, the impacts to the climate are horrendous. The carbon footprint of the Aliso Canyon blowout is thought to be greater than the BP Deepwater Horizon spill in the Gulf of Mexico. Another source of significant methane leaks are the hundreds of thousands of abandoned oil and gas wells (that’s in the United States alone, globally, the number is in the millions) that if improperly sealed, may also be leaking methane gas, uncontrollably. These emissions are destroying our climate many times faster than CO2 emissions, and we must address them.
所以當我們看到石油協會或石油和瓦斯公司的廣告，說天然氣是乾淨的能源，我們就知道那純粹是羅織出來的謊言，是由石油和瓦斯產業所贊助的廣告。甲烷不是一種乾淨的能源。沒有石化燃料是乾淨的，不管是來自怎樣的形狀或方式。我們必須擺脫它們，當然這不會在一夜之間發生，但是我們動作要快。利用天然氣的能源系統，其外洩率很高，在石油和瓦斯提煉和製作過程之中也是如此。石油和瓦斯公司不願意𠄘認，但甲烷在製程中的外洩率非常之高，就像在加州Aliso 峽谷於2015至2016年間的意外事件，共有190,000 公噸的天然氣外洩，直接飄到大氣之中長達5個月，對氣候變遷造成重大影響。Aliso 峽谷噴洩的碳足跡，咸認為比英國石油公司的深水油井Deepwater Horizon 洩油至墨西哥灣所造成的影響要來得大。另外一個主要甲烷外洩的源頭，是數十萬計作廢的油井或瓦斯井(那只是美國境內而言，全球可能高達數百萬個)，如果封閉不良，將不受控制地外洩甲烷氣。這些排放一直破壞著我們的氣候，數倍快於二氧化碳的排放，這是我們必須要處理的。
We must immediately stop methane emissions because they are the immediate short-term threat to reaching tipping points, right alongside black carbon emissions, which are intensely contributing to changing the Earth’s albedo by causing surface darkening with resulting surface heat absorption which in turn leads to accelerated glacier melt.
我們必須馬上阻止甲烷的排放，因為它們是短期內立即的威脅，會將全球暖化推向𨍭捩點，加上碳煙的排放，落著在地球上形成黑色的表面，減少了陽光的反射率，它也吸熱進一步加快了冰川的融化。
讀後
看到一隻皮包骨的北極熊站在一塊浮冰上，不知何去何從，全球暖化融解了它的棲地，北極熊成為生態浩劫下的生物難民，這會是人類未來要面對的困境嗎？
《Meltdown》這本書，探索的是全球暖化之下冰川的加速融化所造成的相關問題。
地球表面，70%是海洋，19%是陸地，11%是冰川。
冰川會反射陽光。冰川的融化和消失，將使地球吸收到更多陽光，進一步使地球更暖。
冰川是調節用水的儲庫，冬天下的冰雪，在春夏秋緩緩融解，使得相關的河域下游長年有水可用。如果冰川融化了，一開始短期似乎會增加水的供給，但是由於冬天的冰雪再也補不齊融化的冰，將可能造成下游無水可用的狀況，尤其是在旱季。
全世界只有2%的水是可以飲用的淡水，而其中大部分(75%)是儲存在冰川之中的。冰川的消失，會造成很嚴重的飲水問題。
冰川融化的水，會造成海平面的上昇。受到地球自轉軸傾斜度和公轉的影響，地球的冰河期大概以每10萬年的周期在寒冷和溫暖之間變動，海平面的高低差可以達到200公尺。我們現在處於冰河時期中較暖的時期(何其幸運)，60%的冰已經融到海中了，如果剩下的40%也再融到海中，那麼海平面將再上昇60公尺。那代表整個台北盆地和高雄及屏東平原皆盡沒於海水之中！當然那可能是很久遠以後的事，但隨著全球暖化，海平面近期上昇幾尺是有可能的，海邊低地泡在海水中的頻率和持續的時間將加長，在那裡置產，風險甚高。
冰川融化，會使得海洋顯得更暖，那代表一旦形成颱風或𩗗風，更大的能量推促之下，會帶來更大的風和雨。全球暖化的後果，似乎就是加劇了旱和澇的現象。
冰川融化也會影響到植物相和動物相。以回溯到近冰川的上游產卵的鮭魚為例，它們就非常可能進一步失去冰涼的棲地，而鮭魚給其他動物帶來的食物，以及隨著母鮭分解而滋養流域而形成的生態圈將被破壞。而這只是比較顯而易見的例子而已。
隨著冰川融化，在高緯度的永凍層也會開始融化，釋放出其中含量豐富的甲烷。而甲烷是溫室效應的超級氣體，這又會進一步加速暖化。另外一方面的潛在問題，是埋藏在永凍冰層之下，很久很久以前的細菌、病毒或其他微生物，會不會就跑了出來而造成疫情，不只對人類，還可能對其他沒有抵抗力的生物產生威脅，成為對現今生態的浩劫呢？
或許是杞人憂天，但是從世界氣候的異常，我們已經看到了事態的端倪。大家保重了。
*：Jorge Daniel Taillant, “Meltdown, The Earth Without Glaciers,” 2021, Oxford University Press
2024/3/16 Meltdown, The Earth Without Glaciers Damakey
