# **1. Introduction**

The escalating impacts of climate change underscore the urgency of a green transition—a pivotal shift toward sustainable practices that is essential for our planet’s future. This transition is expected to accelerate rapidly, necessitating that policy makers analyze its impacts on national labor markets and develop effective strategies to navigate the evolving landscape. Understanding the scope and nature of green jobs is crucial for informing public policy, enabling governments and organizations to develop tailored and targeted strategies for education, training, and employment to support a sustainable economy.

Worldwide, the most widely used source of green job titles is the Green Occupations list, constructed by the U.S. Department of Labor’s Occupational Information Network (O*NET) in 2009 (Dierdorff et al. 2009). O*NET’s original approach involved reviewing publications covering a wide array of workplace topics pertinent to the green economy. In assessing green jobs, research predominantly employs two methods: top-down approaches, which categorize entire sectors or industries as green, and bottom-up approaches, which focus on specific occupations, defining green jobs based on the green nature of the tasks or skills associated with those roles (Valero et al. 2021). O*NET’s classification is the most often used source for occupation retrieval in the bottomup approach to green jobs analysis (OECD 2023).

The green job taxonomy developed by O*NET has been instrumental in shaping quantitative research on the green economy. In the United States, its impact is reflected in studies by researchers such as Consoli et al. (2016), Popp et al. (2020),Vona, Marin, and Consoli (2019), and Vona et al. (2018). The taxonomy has also been adapted for various regions, including the European Union (Bowen and Hancké 2019), the Netherlands (Elliott et al. 2021), the United Kingdom (Valero et al. 2021), Organisation for Economic Cooperation and Development (OECD) member countries (OECD 2023), Viet Nam (Doan et al. 2023), and Argentina (de la Vega, Porto, and Cerimelo 2024). After classifying occupations as green, studies delve into the specific skills and tasks required for green jobs, analyze trends in green job creation and distribution, and assess the broader economic impacts, such as productivity, innovation, and growth, associated with the green transition.

However, two main issues make O*NET less relevant for worldwide use, particularly for green jobs. First, O*NET was built in 2009, with the last major revision of the taxonomy completed in 2011 (Dierdorff et al. 2011) and the associated reference book last updated in 2013 (O*NET 2013). The literature on green jobs has expanded significantly since 2009. Second, O*NET is designed for the U.S. labor market, identifying tasks within occupations based on the U.S. context. The tasks and skills required to perform these jobs depend on the production technology, which can differ significantly between the United States and other economies, such as low- and middle-income countries.

Our study aims to expand the inventory of green job titles by integrating a global perspective and incorporating contemporary sources. Our literature review comprised a search for articles published after 2008 using Scopus and Web of Science—two leading bibliographic databases that are widely used by the academic community for accessing an extensive global collection of peerreviewed publications across various disciplines (Zhu and Liu 2020). The year 2008 marked a 2