研究表明，许多美国人难以准确判断哪些个人决策对气候变化的影响最大。
美国国家科学院（National Academy of Sciences）近期发布的一项研究发现，当被要求对各类行为进行排序时，如将燃油车换成电动车、拼车或减少食物浪费等，受访者对这些行为的气候影响评估普遍失准。燃烧汽油、石油和煤炭释放的温室气体是导致气候变化的主要原因。
报告合著者、斯坦福大学（Stanford University）环境社会科学教授玛达琳娜·弗拉塞亚努指出：“人们会高估一些实际上碳排放影响很小的行为，比如回收利用；而低估那些实际碳排放强度高得多的行为，比如乘飞机或吃肉。”
对气候最有益的三大个人行为，包括避免乘飞机、不养狗以及使用可再生电力，恰恰是最被受访者低估的三项。而对气候变化影响最小的行为分别是更换更节能的家电和灯泡、回收利用以及在洗衣时减少能耗等。这是报告中最被高估的四种行为中的三种。
认知偏差的根源
弗拉塞亚努表示，营销宣传更侧重于回收利用与使用节能灯泡，却回避为何乘飞机或养狗对气候有相对负面的影响，导致受访者更有可能高估这些行为。
人脑的认知机制也是影响因素之一。
不列颠哥伦比亚大学（University of British Columbia）心理学与可持续发展教授赵佳莹（音译）表示：“你能看到瓶子被回收利用的过程。这些是可见的行为。而碳排放却是肉眼看不见的。因此人们不会将乘飞机与排放关联起来。”
她补充说，高频行为更易被记起。她表示：“回收利用几乎是一种日常行为，但乘飞机却并不频繁，而且更少有人讨论，因此公众从心理上更看重回收利用这一行为。”
当然，还有大量误导性信息。例如，有些企业宣扬其进行回收利用工作，却隐瞒整体运营所产生的污染状况。
非营利组织忧思科学家联盟（Union of Concerned Scientists）的气候专家布伦达·埃克沃泽尔表示：“有大量蓄意制造的干扰行为，其目的就是为了支持那些早己过时的政策。”
宠物狗为何会产生较大的气候影响
狗是肉食动物，而肉类消费是导致气候变化的重要因素。这是因为许多食用牲畜的养殖过程会释放导致气候变化的温室气体甲烷。牛肉的影响尤其严重，部分原因是世界各地的养牛场经常占用非法砍伐林地。树木本可吸收二氧化碳（最主要的温室气体），伐林养牛会产生双重影响。
赵佳莹表示：“人们不会将宠物与碳排放关联起来。在人们的脑海中，这两者之间并没有明确的关联。”
然而并非所有宠物都会产生同样的影响。赵佳莹养了一条狗和三只兔子。
她表示：“养100只兔子的排放量也远不及一条狗，因为狗是肉食动物。”
养肉食宠物的主人可选用除牛肉以外的食品减少气候影响。赵佳莹通过喂食海鲜、火鸡等低碳强度蛋白，降低爱犬的碳足迹。
航空出行的污染
飞机排放大量二氧化碳与氮氧化物，这两种气体都属于温室气体。此外，飞机产生的凝结尾迹或蒸汽尾迹还会阻隔温室气体散逸。根据联合国国际民航组织（International Civil Aviation Organization）的数据，纽约至洛杉矶的737航班经济舱往返行程，每位乘客产生逾1,300磅排放。
据联合国估算，仅仅取消一趟航班减少的碳排放量，相当于全年禁食所有肉类或三个多月不使用汽车所减少的排放量。
其他决策的影响力
太阳能、风能等可再生能源不会排放温室气体，因此选择使用这些能源具有巨大的积极影响。个人能够做出的最重要的气候决策包括住宅供暖制冷方式及交通方式选择。转为使用可再生能源可同时最大限度地减少这两项决策的影响。
回收利用虽然能有效减少填埋垃圾，但其运输、处理和回收物再利用环节往往依赖化石燃料，因此气候影响相对较小。美国环保署（Environmental Protection Agency）的数据显示，塑料实际回收利用率不足10%。
冷水洗衣、更换节能灯泡等影响力被高估的其他决策，重要性相对较小。因为相较于乘飞机与养狗等行为，这些家电的影响本就相对较小，虽然优化这些家电确实有益，但对碳排放的影响非常有限。
专家指出，要克服人类在气候相关决策上的误判倾向，最有效的方法就是提供更易获取的信息。赵教授认为，由于获取信息变得更容易，当今公众判断的准确性较一二十年前已经有所提升。
研究证实了这种假设。在受访者完成对各种行为的排序后，研究人员纠正了他们的错误，然后受访者改变了他们原本打算采取的环保行为。
弗拉塞亚努表示：“人们能从干预措施中有所收获。经过学习之后，人们更愿意采取真正更高效的行动。”（*）
美联社气候与环境报道得到多家私人基金会的财务支持。美联社对所有内容全权负责。欢迎登陆AP.org，查看美联社与慈善机构合作的标准，以及支持者和资助报道领域列表。
翻译：刘进龙
审校：汪皓
研究表明，许多美国人难以准确判断哪些个人决策对气候变化的影响最大。
美国国家科学院（National Academy of Sciences）近期发布的一项研究发现，当被要求对各类行为进行排序时，如将燃油车换成电动车、拼车或减少食物浪费等，受访者对这些行为的气候影响评估普遍失准。燃烧汽油、石油和煤炭释放的温室气体是导致气候变化的主要原因。
报告合著者、斯坦福大学（Stanford University）环境社会科学教授玛达琳娜·弗拉塞亚努指出：“人们会高估一些实际上碳排放影响很小的行为，比如回收利用；而低估那些实际碳排放强度高得多的行为，比如乘飞机或吃肉。”
对气候最有益的三大个人行为，包括避免乘飞机、不养狗以及使用可再生电力，恰恰是最被受访者低估的三项。而对气候变化影响最小的行为分别是更换更节能的家电和灯泡、回收利用以及在洗衣时减少能耗等。这是报告中最被高估的四种行为中的三种。
认知偏差的根源
弗拉塞亚努表示，营销宣传更侧重于回收利用与使用节能灯泡，却回避为何乘飞机或养狗对气候有相对负面的影响，导致受访者更有可能高估这些行为。
人脑的认知机制也是影响因素之一。
不列颠哥伦比亚大学（University of British Columbia）心理学与可持续发展教授赵佳莹（音译）表示：“你能看到瓶子被回收利用的过程。这些是可见的行为。而碳排放却是肉眼看不见的。因此人们不会将乘飞机与排放关联起来。”
她补充说，高频行为更易被记起。她表示：“回收利用几乎是一种日常行为，但乘飞机却并不频繁，而且更少有人讨论，因此公众从心理上更看重回收利用这一行为。”
当然，还有大量误导性信息。例如，有些企业宣扬其进行回收利用工作，却隐瞒整体运营所产生的污染状况。
非营利组织忧思科学家联盟（Union of Concerned Scientists）的气候专家布伦达·埃克沃泽尔表示：“有大量蓄意制造的干扰行为，其目的就是为了支持那些早己过时的政策。”
宠物狗为何会产生较大的气候影响
狗是肉食动物，而肉类消费是导致气候变化的重要因素。这是因为许多食用牲畜的养殖过程会释放导致气候变化的温室气体甲烷。牛肉的影响尤其严重，部分原因是世界各地的养牛场经常占用非法砍伐林地。树木本可吸收二氧化碳（最主要的温室气体），伐林养牛会产生双重影响。
赵佳莹表示：“人们不会将宠物与碳排放关联起来。在人们的脑海中，这两者之间并没有明确的关联。”
然而并非所有宠物都会产生同样的影响。赵佳莹养了一条狗和三只兔子。
她表示：“养100只兔子的排放量也远不及一条狗，因为狗是肉食动物。”
养肉食宠物的主人可选用除牛肉以外的食品减少气候影响。赵佳莹通过喂食海鲜、火鸡等低碳强度蛋白，降低爱犬的碳足迹。
航空出行的污染
飞机排放大量二氧化碳与氮氧化物，这两种气体都属于温室气体。此外，飞机产生的凝结尾迹或蒸汽尾迹还会阻隔温室气体散逸。根据联合国国际民航组织（International Civil Aviation Organization）的数据，纽约至洛杉矶的737航班经济舱往返行程，每位乘客产生逾1,300磅排放。
据联合国估算，仅仅取消一趟航班减少的碳排放量，相当于全年禁食所有肉类或三个多月不使用汽车所减少的排放量。
其他决策的影响力
太阳能、风能等可再生能源不会排放温室气体，因此选择使用这些能源具有巨大的积极影响。个人能够做出的最重要的气候决策包括住宅供暖制冷方式及交通方式选择。转为使用可再生能源可同时最大限度地减少这两项决策的影响。
回收利用虽然能有效减少填埋垃圾，但其运输、处理和回收物再利用环节往往依赖化石燃料，因此气候影响相对较小。美国环保署（Environmental Protection Agency）的数据显示，塑料实际回收利用率不足10%。
冷水洗衣、更换节能灯泡等影响力被高估的其他决策，重要性相对较小。因为相较于乘飞机与养狗等行为，这些家电的影响本就相对较小，虽然优化这些家电确实有益，但对碳排放的影响非常有限。
专家指出，要克服人类在气候相关决策上的误判倾向，最有效的方法就是提供更易获取的信息。赵教授认为，由于获取信息变得更容易，当今公众判断的准确性较一二十年前已经有所提升。
研究证实了这种假设。在受访者完成对各种行为的排序后，研究人员纠正了他们的错误，然后受访者改变了他们原本打算采取的环保行为。
弗拉塞亚努表示：“人们能从干预措施中有所收获。经过学习之后，人们更愿意采取真正更高效的行动。”（*）
美联社气候与环境报道得到多家私人基金会的财务支持。美联社对所有内容全权负责。欢迎登陆AP.org，查看美联社与慈善机构合作的标准，以及支持者和资助报道领域列表。
翻译：刘进龙
审校：汪皓
It turns out many Americans aren’t great at identifying which personal decisions contribute most to climate change.
A study recently published by the National Academy of Sciences found that when asked to rank actions, such as swapping a car that uses gasoline for an electric one, carpooling or reducing food waste, participants weren’t very accurate when assessing how much those actions contributed to climate change, which is caused mostly by the release of greenhouse gases that happen when fuels like gasoline, oil and coal are burned.
“People over-assign impact to actually pretty low-impact actions such as recycling, and underestimate the actual carbon impact of behaviors much more carbon intensive, like flying or eating meat,” said Madalina Vlasceanu, report co-author and professor of environmental social sciences at Stanford University.
The top three individual actions that help the climate, including avoiding plane flights, choosing not to get a dog and using renewable electricity, were also the three that participants underestimated the most. Meanwhile, the lowest-impact actions were changing to more efficient appliances and swapping out light bulbs, recycling, and using less energy on washing clothes. Those were three of the top four overestimated actions in the report.
There are many reasons people get it wrong
Vlasceanu said marketing focuses more on recycling and using energy-efficient light bulbs than on why flights or dog adoption are relatively bad for the climate, so participants were more likely to give those actions more weight.
How the human brain is wired also plays a role.
“You can see the bottle being recycled. That’s visible. Whereas carbon emissions, that’s invisible to the human eye. So that’s why we don’t associate emissions with flying,” said Jiaying Zhao, who teaches psychology and sustainability at the University of British Columbia.
Zhao added it’s easier to bring actions to mind that we do more often. “Recycling is an almost daily action, whereas flying is less frequent. It’s less discussed,” she said. “As a result, people give a higher psychological weight to recycling.”
Of course, there is also a lot of misleading information. For example, some companies tout the recycling they do while not telling the public about pollution that comes from their overall operations.
“There has been a lot of deliberate confusion out there to support policies that are really out of date,” said Brenda Ekwurzel, a climate scientist with the Union of Concerned Scientists, a nonprofit.
Why dogs have a big climate impact
Dogs are big meat eaters, and meat is a significant contributor to climate change. That is because many of the farm animals, which will become food, release methane, a greenhouse gas that contributes to climate change. Beef is especially impactful, in part because around the world cattle are often raised on land that was illegally deforested. Since trees absorb carbon dioxide, the most abundant greenhouse gas, cutting them to then raise cattle is a double whammy.
“People just don’t associate pets with carbon emissions. That link is not clear in people’s minds,” Zhao said.
Not all pets are the same, however. Zhao owns a dog and three rabbits.
“I can adopt 100 bunnies that will not be close to the emissions of a dog, because my dog is a carnivore,” she said.
The owner of a meat-eating pet can lower their impact by looking for food made from sources other than beef. Zhao, for example, tries to minimize her dog’s carbon footprint by feeding her less carbon-intensive protein sources, including seafood and turkey.
Pollution from air travel
Planes emit a lot of carbon dioxide and nitrogen oxides, also greenhouse gases. Additionally, planes emit contrails, or vapor trails that prevent planet-warming gases from escaping into space. A round-trip economy-class flight on a 737 from New York to Los Angeles produces more than 1,300 pounds of emissions per passenger, according to the International Civil Aviation Organization, a United Nations agency.
Skipping that single flight saves about as much carbon as swearing off eating all types of meat a year, or living without a car for more than three months, according to U.N. estimates.
Other decisions, both impactful and minor
Switching to energy that comes from renewable sources, such as solar and wind, has a large positive impact because such sources don’t emit greenhouse gases. Some of the biggest climate decisions individuals can make include how they heat and cool their homes and the types of transportation they use. Switching to renewable energy minimizes the impact of both.
Recycling is effective at reducing waste headed for landfill, but its climate impact is relatively small because transporting, processing and repurposing recyclables typically relies on fossil fuels. Plus, less than 10% of plastics actually get recycled, according to the Environmental Protection Agency.
Other decisions with overestimated impact, including washing clothes in cold water and switching to more efficient light bulbs, are relatively less important. That is because those appliances have a relatively small impact compared to other things, such as plane flights and dogs, so improving on them, while beneficial, has a much more limited influence.
Experts say the best way to combat the human tendency to miscalculate climate-related decisions is with more readily available information. Zhao said that people are already more accurate in their estimations than they would have been 10 or 20 years ago because it’s easier to learn.
The study backs up that hypothesis. After participants finished ranking actions, the researchers corrected their mistakes, and they changed which actions they said they’d take to help the planet.
“People do learn from these interventions,” Vlasceanu said. “After learning, they are more willing to commit to actually more impactful actions.”
The Associated Press’ climate and environmental coverage receives financial support from multiple private foundations. AP is solely responsible for all content. Find AP’s standards for working with philanthropies, a list of supporters and funded coverage areas at AP.org.