? 全球溫室氣體排放在2021年有所增加，在2020年全球溫室氣體排放大幅下降后積聚的熱情和希望受到了一定程度的打擊  

? 現實情況是，主要的生活方式和工業變化是由疫情引起的，當世界再次開放時，溫室氣體排放量總是會增加  

? 然而，2021年的溫室氣體排放量仍比2019年下降5%，這可能表明全球溫室氣體排放軌跡發生了細微變化  

據美國油價網報道，盡管各國承諾削減碳排放并向可再生能源過渡，但全球溫室氣體排放量仍在上升。 對2020年全球排放量下降的樂觀情緒(主要是由于對疫情防控的社交限制和生活方式的改變)以及對第26屆聯合國氣候變化大會(COP26)提出的國際行動的熱情，可能是被誤導。

雖然世界各地的許多政府和能源公司都有碳減排和凈零排放的雄心，但在低碳能源變得更廣泛之前，我們可以期待看到高水平的碳排放。 與2020年相比，美國2021年的溫室氣體排放量增加了6.2%，盡管人們希望疫情期間的行為轉變會推動持久的改變。 在疫情的第一年，環境活動人士強調，隨著人們開始在家工作，不再頻繁旅行，以及工業運營放緩，排放量有所下降。 有可能做出有意義的改變的想法，促使活動人士、年輕人，甚至政府提出改變的必要性。 

然而，在2021年，我們似乎在迅速倒退，世界上很多人又回到了老習慣。 由于道路和空中交通的恢復以及大多數行業的運營恢復，溫室氣體排放量必然會增加。 例如，與2020年相比，2021年美國的交通行業的溫室氣體排放增加了約10%。 

進行這項研究的榮鼎集團(Rhodium Group)的凱特?拉森表示：“我們預計會出現反彈，但令人沮喪的是，溫室氣體排放反彈的速度甚至快于整體經濟。”事實上，“我們不僅在減少經濟中的碳強度，我們還在增加它。”“我們現在做的恰恰是我們應該做的事情的反面，”拉森解釋道。  

顯然減排任務還有很長的路要走，在去年嚴重的石油和天然氣短缺之后，世界上有好幾個國家轉向了煤炭——最臟的化石燃料——來彌補這一缺口。 盡管近幾年來美國的煤炭使用量下降，但2021年的煤炭發電產量比2020年增加了17%。 這不僅發生在美國。 根據國際能源署(IEA)的數據，煤炭產量在2021年創下歷史新高，需求水平將在2022年達到峰值。 

英國目前計劃在2024年之前逐步淘汰所有的煤炭生產，而且似乎走上了正確的軌道，在去年夏季實現了具有里程碑意義的三天無煤期，但英國不得不在去年9月運行燃煤發電廠以滿足國內電力需求。 由于面臨天然氣短缺和價格大幅上漲，英國又轉而使用煤炭為國內供電。

拉森說，“與我們在2020年至2021年期間看到的一些變化相比，全球溫室氣體排放量被認為上升了4.9%，在過去一年里，大約有360億噸二氧化碳被排放到大氣中。 在歐洲，去年春天歐盟國家的溫室氣體排放量增加了18%。 家庭貢獻了近五分之一的溫室氣體排放，主要的罪魁禍首是交通行業和供暖。

全球碳項目主席羅布·杰克遜談到這一趨勢時說：“我們預計，當世界經濟恢復到接近正常水平時，就會出現溫室氣體排放反彈。” 拉森補充道：“把汽車停開一年，當你再開的時候，它還是一輛污染嚴重的汽車。 同樣道理，當經濟活動恢復時，溫室氣體排放也會恢復。”

杰克遜說，“然而，我們有理由抱有希望，因為2021年的溫室氣體排放量比2019年下降了5%，這表明變化可能正在發生，只是沒有以許多人希望的速度發生。 在1990年至2020年期間，盡管歐盟人口增長，旅游人數增加，溫室氣體排放量卻下降了31%。 這反映了政府鼓勵減排政策的轉變，以及過去30年對可再生能源投資的增加。 當政府和能源公司共同努力實現改變時，它表明有改變的潛力。”

世界上許多政府都在依靠油氣公司來降低排放，提高該行業的稅收，并要求石油巨頭擴大投資組合，將低碳石油生產和可再生能源項目納入其中。 但是，要實現有意義的改變，政府、公共機構和私營部門必須共同努力，以COP26承諾的速度發展可再生能源領域。 許多國家的目標是到2050年前實現凈零排放，如果他們希望實現這一目標，他們將不得不加快能源轉型的步伐。  

李峻 編譯自 美國油價網

原文如下：

Why Global Emissions Bounced Back In 2021?

·     Global greenhouse gas emissions increased in 2021, denting some of the enthusiasm and hope that had built up after a significant drop off in 2020

·     The reality is that major lifestyle and industry changes were caused by a global pandemic and emissions were always going to increase when the world opened up again

·     The emissions in 2021 were still down five percent from 2019 however, which might point to a slight change in the trajectory of global emissions 

Greenhouse gas emissions are up worldwide despite big promises for carbon-cutting and a transition to renewables. Optimism around the drop in emissions throughout 2020, mainly owing to pandemic restrictions and a change in lifestyle, as well as enthusiasm around international action coming out of COP26, was perhaps misguided. 

While many governments and energy companies around the world have carbon-reduction and net-zero ambitions, we can expect to see high levels of carbon emissions until low-carbon energy becomes more widely available. Emissions in the U.S. rose 6.2 percent in 2021 compared to 2020 despite hopes that a shift in behavior during the pandemic would spur lasting change. Throughout the first year of the pandemic, environmental activists highlighted the drop in emissions that occurred as people began to work from home, stopped traveling so much, and as industrial operations slowed down. The idea that it was possible to make a meaningful change led activists, youths, and even governments to suggest the need for change. 

Yet, in 2021 we seem to have backtracked rapidly, with much of the world population returning to old habits. As road and air traffic picked up and operations resumed across most industries, emissions were bound to increase. For example, there was around a10 percent increase in transport emissions in the U.S. in 2021 compared to 2020.

Kate Larsen, from the Rhodium Group that carried out the study, stated “We expected a rebound but it’s dismaying that emissions came back even faster than the overall economy.” In fact, “We aren’t just reducing the carbon intensity of the economy, we are increasing it. We are doing exactly the opposite of what we need to be doing,” she explained.

There is clearly still a long way to go and following severe oil and gas shortages last year, several countries around the world turned to coal – the dirtiest fossil fuel – to bridge that gap. Despite the use of coal in the U.S. declining in recent years, coal energy production increased by 17 percent in 2021 from 2020. And this was not only the case in America. Coal production was set to hit an all-time high in 2021 according to the International Energy Agency (IEA), with demand levels peaking in 2022. 

The U.K., which currently plans to phase out all coal production by 2024 and seemed to be on the right track - achieving a landmark coal-free three-day period in the summer - had to run coal plants in September to meet electricity demand. As the country faced natural gas shortages and a significant hike in prices, it shifted back to using coal to power the nation.

In relation to several of the changes we saw between 2020 and 2021, worldwide greenhouse gas emissions are thought to have risen by 4.9 percent, with approximately 36 billion tonnes of carbon dioxide being released into the atmosphere over the past year. In Europe, greenhouse gas emissions from EU countries increased by 18 percent last spring. Households contributed just under a fifth of emissions and the main culprits were transportation and heating. 

Rob Jackson, chair of the Global Carbon Project stated of the trend, “We expected this rebound when the world’s economy returned close to normal.”, adding “Park your car for a year and it’s the same polluting vehicle when you start it again. Similarly, when economic activity returns, so do emissions,” he explained.

There is reason to be hopeful, however, as 2021 greenhouse gas emissions were down by 5 percent from 2019, suggesting that change may be taking place, just not at the speed many had hoped for. Across the EU, greenhouse gas emissions dropped by 31 percent between 1990 and 2020, despite a growth in population and an increase in travel. This reflects the shift in government policies to encourage emissions cuts as well as the increased investment in renewable alternatives over the last three decades. It demonstrates the potential for a shift when governments and energy companies work together towards change. 

Many governments around the world are relying on oil and gas companies to lower their emissions, increasing taxes on the sector and requiring oil majors to expand their portfolios to include low-carbon oil production and renewable energy projects. But to make meaningful change, governments, public institutions, and private players must work together to develop the renewable energy sector at the rate promised coming out of the COP26 summit. With many countries aiming for net-zero by 2050, they will have to pick up the pace of the energy transition if they hope to achieve this goal.