它远非气候专家的常态，以便提供可能被称为的东西，所有事情都考虑过，相当积极的新闻。但是，2020年并不正常年份。
正如已妥善的文件所示，由于Covid-19大流行导致的经济衰退，预计2020年将在全球温室气体排放中看到前所未有的平时下降。但是，每年这一十年，随着经济恢复的，每年都需要相似的每年减排，预计未来几年的排放将强劲反弹。如果它尚不明显，深入，全球经济的系统变化都是迫切需要推动将世界追踪所需的排放的深度持续削减，以满足巴黎协定的目标并避免气候灾难。
然而，由于近几个月从世界领导者的地标气候承诺进行了势头，现在日益增长的希望是全球经济的急需，全球经济的重新制作，这些经济嵌入了长期的绿色基础设施，流程和行为最终可能在卡片上。
Such a goal remains, as it always has been, a tall order. But it is hard not to feel a little buoyed by last week's鼓励调查结果from climate scientists and policy experts at the Climate Action Tracker (CAT) initiative, who have assessed the planet's potential global warming pathway should countries and world leaders deliver on the emissions reduction promises they have made to date.
Since September alone, China has pledged to reach carbon neutrality by 2060, and Japan, South Korea, South Africa and Canada also have set their sights on net-zero by 2050. Add these commitments up alongside pre-existing national climate commitments around the world, such as the EU's landmark net-zero goal, and President-elect Joe Biden's promise to put the U.S. on a net-zero footing by 2050, and 63 percent of the global greenhouse gas emissions are emitted in territories soon to be governed by some form of net-zero commitment.
We have been doing this work for years now, and it's usually a frustrating business to see that not much is moving. But indeed, now in the last 3 months, I have been positively surprised by what's possible.
All in all, CAT estimates that if governments and world leaders follow deliver on these public commitments, the world could move onto a 2.1 degree Celsius global warming trajectory, putting the Paris Agreement goal to limit average temperature rise to 2 C or "well below" 1.5 C "within reach. Even if the U.S. and other net-zero pledges where the precise legal status of the targets remains unclear are removed from the calculations, then CAT still reckons current commitments could deliver a 2.24 C temperature trajectory. It may be a depressingly long way from "mission accomplished," but it is also a far cry from the 2.7 C to 3.7 C projected warming range calculated in 2015 based on the emissions reductions goals submitted under the Paris Agreement.
尼克拉斯赫恩（NiklasHöhne教授 - 猫伴侣组织 - 过去几个月是一个令人欢迎的惊喜。毕竟，曾为猫的分析作出贡献多年，他也被用作潜行气候行动进展的人。
"For us, it's unusual to have positive news," he tells BusinessGreen. "We have been doing this work for years now, and it's usually a frustrating business to see that not much is moving. But indeed, now in the last three months, I have been positively surprised by what's possible."
China's 2060 pledge appeared to trigger a tipping point that saw Japan, South Korea, South Africa and others follow in the space of just weeks, he explains. "It's all a dynamic I did not see coming four months ago," says Höhne.
这是非常令人鼓舞的消息。尽管如此，要注意猫的分析，以及必须扩大的巨大的政治，经济，社会和技术障碍，这是至关重要的，以便在净零承诺的历史浪潮中提供稳定的气候。
But focusing solely on the size of the journey ahead risks masking how much progress has been made, and how quickly. And arguably, the pace of change underscored by CAT's analysis is most galvanizing.
“这就是为什么我认为有一种正在发生的多米诺骨牌效应或波浪，”Höhne解释道。“如果我们在过去四个月中看到的快速速度持续，那么我认为我们将有其他国家很快推迟。”
Indeed, it is worth noting how rapidly the outlook has changed. CAT has been analyzing the effects of policy pledges on planetary warming since 2009, the year of the dispiriting COP15 U.N. climate change summit in Copenhagen, at which no meaningful agreement to cut emissions was brokered. Back then, CAT's estimate for global average temperature rise by 2100 was 3.5 C. Fast forward to 2015 after the Paris Agreement was adopted at COP21 in France, which saw almost every nation on the planet commit to limiting global warming, and CAT's estimate had fallen significantly to 2.7 C. Now, just as governments envisaged when they included a ratchet mechanism in the Paris Agreement that required countries to submit new emissions plans every five years, the outlook has improved again.
"I think the critical mass has now been achieved," Höhne adds. "It seems to me that it is very difficult now to stay out."
当然，过去五年几乎没有普通航行。白宫过去四年被气候态度占领，由于全球大流行，COP26推迟，气候外交冒着背部燃烧器。排放量可能在巴黎协议的直接急照中，加油希望经济增长和排放已经脱钩，但他们开始在十年结束时再次攀升。
仍有很长的路要走，仍有37％的全球温室气体排放仍然被净零的目标覆盖，主要发射者可能会继续坚持适当雄心勃勃的脱碳目标。
But now, with the escalation of net-zero commitments in the run-up to COP26, and the potential of more ambitious national decarbonization plans emerging in the next fortnight to coincide with the upcoming U.N. Climate Ambition Summit, it is suddenly possible to envisage how global decarbonization could start to gather pace over the coming years.
"I think this issue of net-zero targets is really a breakthrough," says Höhne. "That was already in the Paris Agreement in 2015 that all countries should go to net-zero, but now individual countries as large as China, the U.S. and EU are really serious about it, and that is new."
这种乐观感进一步放大了资金和技术趋势，支撑了新的净零目标。过去五年已经看到可再生能源的成本下降，智能电网技术推进和电动车进入主流，甚至碳密集型产业已经开始映射可靠的脱碳途径。一支生长的工业化国家乐队已经证明，可以在仍然提高生活水平的同时提供深度排放，而通过移动近海清洁技术的一些排放减排也起到了关键作用。各国政府一直确信设定更加雄心勃勃的排放目标，因为现在有证据基础，表明他们可以实现。
有很好的理由相信更多国家，地区，各国和企业将通过在明年11月在格拉斯哥的关键COP26气候峰会上延伸临时目标来实现雄心勃勃的净零目标。但是还有很长的路要走，仍有37％的全球温室气体排放仍然被净零的目标所涵盖，俄罗斯，沙特阿拉伯，尼日利亚和伊朗等主要发射者可能会继续持续坚持适当雄心勃勃鉴于他们化石燃料占主导地位的经济体，脱碳目标是相当一段时间。
And even then, while long-term climate targets are crucial in setting the ambition, pledges alone do not automatically equate to action on the ground. Near-term decarbonization targets for 2030 are likely to play a critical role in determining whether CAT's encouraging temperature projections can be realized. Yet here global commitments remain far below par, with most national climate plans for 2030 submitted under the Paris Agreement still not in line with delivering net zero by 2050. The United Kingdom was the first major economy to set a legal net-zero target nearly 18 months ago, but the government's decarbonization strategy is still not in line with the emissions trajectory required to meet the goal. Many other countries are experiencing precisely the same disconnect between their admirable long term emissions targets and inadequate short term climate policies.
因此，猫估计，即使在2020年的排放中的Covid-19下降，全球温室气体实际上是为了保持上升到2030年，当时全球排放需要被切成两半，以便避免有机会限制全球变暖至1.5℃。
Sobering现实是，承诺的净零计划的执行面临着巨大的挑战，留下挫折或延误的时间很少。如果他们是遏制排放，难以脱碳，如航空，航运和重型行业等行业面临巨大的技术挑战。即使在低碳替代技术存在的电力和公路运输等领域，清洁技术提供商也面临强大的现任者和众多政策障碍。随着特朗普实验所示，对气候行动的政治共识可以很快破裂，破坏净零转型的投资。公众舆论投票世界过度表现出对气候危机的增长令人担忧和对清洁技术的支持，但从高碳惯例的过渡造成的破坏可能会引发相当大的反对。
Moreover, achieving net-zero emissions by mid-century is really only half of the story. Almost all scenarios for limiting temperature rises to 1.5 C require some sort of carbon dioxide removal from the atmosphere in the second half of the century — including natural measures such as forestry and soil sequestration, as well as carbon capture technologies — in order to essentially go beyond net-zero to "net negative" after 2050. "Going to net-zero is probably not enough, because we are simply too late," Höhne concedes. "We need to go to net-zero and afterwards to net negative, so removing CO2 emissions from the atmosphere."
许多国家和企业零目标的依赖at least in part on negative emissions projects and technologies, the bulk of which have not been tested at scale or could turn out to be unviable. For example, thousands of businesses have pledged to become carbon neutral by securing various carbon offsets, but experts fear there is simply not sufficient land to plant trees for all of them. Some climate scientists, including University of Manchester professor Kevin Anderson,因此已经估计了如果从等式中除去负排放假设，则全球变暖轨迹将在年底到2.5 C和3 C之间，远远高于猫的分析和可能导致灾难性经济和社会后果的水平在本世纪下半叶。
There are uncertainties, but uncertainty should not be taken as an excuse not to do anything and assume it's impossible. ... Let's focus on what we know. We know how to reduce emissions to 0 in almost all sectors.
但是猫的分析假设一旦国家意图ch their net-zero targets, they do not make additional efforts to move to significant net negative emissions. If they do, it estimates net negative emissions could double the reduction in the temperature trajectory. So, if the global impact of U.S. achieving net zero emissions by 2050 is to knock 0.1 C of the global warming trajectory, the emergence thereafter of a net negative emission economy could see the country knock 0.2 C from the global warming trajectory by 2100. Meanwhile, engineers and investors are stepping up their pursuit of effective negative emission technologies that could remove carbon dioxide direct from the atmosphere and make such negative emission scenarios a reality.
And there are signs that the projected warming trajectory could be lower still. So far, only Norway and Chile have come forward with more ambitious climate plans — or nationally determined contributions (NDCs) in the U.N. jargon — since the Paris Agreement was adopted five years ago, but if all other signatures follow suit over the next 12 months, the planet's warming trajectory would drop further, according to CAT's analysis. The success of COP26 next year in Glasgow therefore largely will be determined by how many countries raise their ambitions in support of the Paris Agreement. Just last week,Financial Times reportedU.K. Prime Minister Boris Johnson is considering strengthening the U.K.'s 2030 emissions target as part of a new NDC for the Summit host.
"Currently, all short-term targets fall short of what's necessary and are not in line with the long-term ambition to go to net-zero, and that applies to basically all countries," acknowledges Höhne. "So the next 10 years are absolutely crucial to even put them on a path towards net-zero. If we don't get it right in the next 10 years, then we cannot meet those ambitious goals."
它仍然是警告剧烈的警告，但对于所有Höhne对他的岁月的失望分析了气候政策，他对人类克服了许多障碍的潜力看涨。“存在不确定性，但不应该被视为不做任何事情的借口，并认为这是不可能的，”他争辩说。“所以让我们专注于我们所知道的。我们知道如何在几乎所有部门中减少排放到零。我们今天拥有技术，只有一些我们没有。”
在造成无国痛苦和巨大破坏的大流行中，它突然设想明年COP26首脑会议导致可靠的目标和战略，这些目标和策略将根据巴黎协议的目标，限制全球温度增加低于2 C，避免了最严重的气候影响。在这一点这一点上，许多观察者甚至可以根据贬低的贬值和前所未有的索偿规模造成的脱碳挑战，若干损坏的影响，甚至是最轻盈的自满情绪。但鉴于五年前设想的灾难性变暖轨迹，它也将代表真正显着的进展。
