In comparison, the United States leads in carbon emissions from email usage, generating 3,207 tonnes of CO2 daily, and accounting for 6.82% of global email traffic. With 89.45% of Americans actively using email, each user sends or receives an average of 31.72 emails per day, resulting in a per capita emission of 9.52 grams of CO2.

Germany follows closely, with its email traffic resulting in 2,810 tonnes of CO2 emissions each day. Among the German population, 83% are active email users, handling an average of 123.01 emails daily, leading to a per capita emission of 36.90 grams. Ireland stands out for its high per capita emissions, with each user contributing approximately 532 grams of CO2 daily, resulting in a national total of 2,777 tonnes. This high rate is attributed to the 93% of Irish residents who use email extensively.

Further down the list, the Netherlands and the United Kingdom emit 2,761 and 2,751 tonnes of CO2 daily from emails, respectively. Dutch users contribute about 157.51 grams each to the carbon footprint, while British users add about 43.21 grams.

France, with a 94% email user rate, sees its daily email use leading to 2,748 tonnes of CO2 emissions. Similarly, Austria's email activities result in 2,734 tonnes of emissions daily, with its users having one of the highest per capita emissions at 345.46 grams.

A spokesperson from Zero Bounce commented on the findings, underscoring the importance of recognising the environmental impact of digital communication practices. They noted, "There is a substantial carbon emission from email usage that highlights the need for greater awareness and strategies to reduce the digital carbon footprint. Understanding these impacts is crucial for developing sustainable solutions and mitigating climate change."

The study not only provides insights into digital behaviours across different countries but also emphasises the varying environmental impacts of everyday activities like emailing, advocating for a global shift towards more sustainable digital practices.