You might not realise it, but sending even a short email has an impact on the environment. Scientists estimate that an email adds about four grams (0.14 ounces) of carbon dioxide equivalent into the atmosphere.

你可能没有意识到，即使是发送一封小小的邮件也会对环境产生影响。科学家估计，发送一封邮件相当于向大气中排放约4克的二氧化碳。

That means that hitting 'send' on 65 mails is equal to driving an average-sized car a 0.6 miles (1km).

这意味着，发送65封邮件所产生的二氧化碳相当于一辆普通大小的汽车行驶1公里产生的二氧化碳。

This is according to a McAfee study the 'Carbon Footprint of Spam', which also found each time you copy someone else, another six grams of CO2 is added. A carbon footprint is the total amount of greenhouse gases produced to directly and indirectly¹ support human activities, usually expressed in equivalent tons of carbon dioxide.

据迈克菲（一款杀毒软件）“垃圾邮件的碳足迹”研究发现，每次转发邮件同样也会增加6克的二氧化碳。碳足迹是人类活动直接或间接地向大气中排放温室气体的总量，通常也用同等数量的二氧化碳的吨数来表示。

The average person sends and receives 125 emails every day. When sending emails, greenhouse gases are produced in running the computer, server and routers, and when when the equipment was manufactured. Receiving a spam message, even if you do not open it, has an environmental impact of 0.3 gCO2.

每人平均每天收发125封邮件。发送邮件时，电脑、服务器、路由器的运行会产生温室气体，同时制造这些设备时也会产生二氧化碳。收到一条垃圾信息，即使你没有打开，大气中也会增加0.3克二氧化碳。

The global carbon footprint from spam annually² is equivalent to the greenhouse gases pumped out by 3.1 million passenger cars using two billion gallons of gasoline in a year.

每年全球垃圾邮件的碳排放量相当于310万辆客车每年消耗20亿加仑的汽油所排出的二氧化碳。

Sending emails is just one activity on a long list of seemingly harmless everyday actions contribute to emissions³ of CO2. For example, typing in a non-essential Google inquiry⁴ on an energy-efficient laptop leaves a footprint of 0.2 gCO2e. On an old desktop⁵ computer, it is 4.5 gCO2e. Sending a text message isn't a less harmful method of communication either, as it comes at a cost of about 0.014 gCO2e.

发送邮件只是人类日常生活中看似无害却会排放二氧化碳的众多行为中的一项。例如，用节能笔记本在谷歌上搜索一般的问题会产生0.2克的二氧化碳，而用老式电脑则会产生4.5克二氧化碳。发送短信同样会对环境产生影响，因为会产生约0.014克二氧化碳。