Global research on carbon footprint: A scientometric review

Highlights

• Diversified and interdisciplinary research took place after 2008.

• Most international cooperation takes place between European and American scholars.

• Institutions and scholars in developing countries are still backward and marginalized.

• Obious theme drift and knowledge evolution appeared from 1992 to 2019.

• The research of carbon footprint tends to be integrated with economics.

Abstract

In the context of global climate change, carbon footprint research has become a hot spot for many regions and scholars. However, a global, systematic and intuitive literature review of carbon footprint is still lacking, which has become the motivation of this research. Based on 7450 articles in the Web of Science Core Collection, this study conducted a literature review and analysis of carbon footprint from the perspective of scientometric. It is found that between 1992 and 2019, the theme of carbon footprint research has changed from ecology and botany to international trade and household behaviours, etc. Water vapour is the longest lasting carbon footprint research topic. The research scope shows a trend from small to large, that is, from the level of individuals and families to enterprises and organizations, and then to the countries and regions. Year 2008 is the main node in carbon footprint research: the classic literature before 2008 is the hubs of later research; the research after 2008 shows a significant trend of diversification and interdisciplinary development. The China's research institutions and scholars have shown an explosive trend after 2008. However, most international cooperation still occurs between North American and European countries, while developing countries such as China are still in the marginal area. The main source of knowledge for carbon footprint research is the subject “Veterinary, Animal, Science”; relatively, the research results are mainly applied to the subject “Environmental, Toxicology, Nutrition”. In addition, it is worth noting that carbon footprint research is showing a trend of merging with Economics research. These trends prove that there has been a significant theme drift and knowledge evolution process in carbon footprint research.

Introduction

Global crises such as extreme weather, air pollution, reduced food production, rising sea levels, and spread of epidemics caused by climate change have become major tests for countries in the process of sustainable socio-economic development. The large amount of carbon emissions generated by human activities contributes to this phenomenon (IPCC 2013). On the basis of extensive international cooperation, many countries have begun to treat measures conducive to reducing carbon emissions as a major national strategy platform (Aichele and Felbermayr 2012; Ivanova et al. 2017). It is imperative to explore a feasible and scientific carbon emission measurement method to ensure sustainable development. The proposal of carbon footprint vividly reveals the effect of human behaviours on climate change and provides an effective tool for scientifically measuring carbon emissions. Quantitative analysis based on carbon footprint not only facilitates exploration of the concentration areas and intensity of carbon emissions, but also provides a basis for taking targeted measures and periodic supervision thereof. Meanwhile, it is helpful for scholars to connect different levels of carbon consumption with a unified theme (He et al. 2019; Lenzen et al. 2018), so that different research perspectives have a unified reference basis. The advantages of carbon footprint are conducive to the adoption of unified goals and actions by stakeholders in various fields in the process of reducing carbon emissions and promoting global sustainable development. Therefore, it is necessary to review and categorise carbon footprint research, to understand the internal reasons for the rapid increase in global carbon emissions and the corresponding control mechanisms.

Since the concept of Ecological Footprint was proposed, the carrying capacity and sustainability mechanisms of human socio-economic systems have begun to attract attention (Rees 1992; Wackernagel et al. 1999). The Carbon Footprint is one of its most important conceptual extensions. Although many scholars have defined the scope of the carbon footprint based on their own research perspectives, a more unified definition of carbon footprint has yet to be formed (Matthews et al. 2008). In this research, the Carbon Footprint is defined as a measure of the exclusive total amount of carbon dioxide emissions that is directly and indirectly caused by an activity or is accumulated over the life stages of a product (Wiedmann and Minx 2008). From the perspective of this definition, unlike the meaning of carbon emissions, carbon footprint is more inclined to focus on carbon emissions during the full life cycle (of products) from the perspective of consumer responsibility. This expressive perspective is also reflected in the metaphorical expression of the word “footprint”. It is precisely based on this metaphorical expression that the research into “carbon footprint” is moving towards a generalised research paradigm in the macro-context of climate change (Peters 2010).

From the perspective of carbon footprint research content, the initial discussion mainly involves the definition, the meaning, existence of, and the introduction of greenhouse gas emissions (Rees 1992; Wackernagel et al. 1999), and even the purpose of public welfare propaganda. With the deepening of research, correlation measurement methods and tools have become a focus for scholars (Weidema et al. 2008; Wiedmann 2009; Wood and Garnett 2010). Relatively speaking, the specific application and practice of carbon footprint is the focus of current research (Malmodin and Lundén 2018; Sommer and Kratena 2017; Zhang et al. 2017). Its research scope and target topics also appeared to be following an expansive research track similar to the research content. Discussions based on the carbon footprint of individuals and families can help arouse social attention and facilitate continuous discussions (Wackernagel and Rees 1998; Weber and Matthews 2008), which is undoubtedly an ideal way to start. With the continuous enrichment of research methods based on life cycle analysis (LCA) and input-output analysis (IOA), the effective measurement of carbon footprint on carbon emissions has begun to be applied to enterprises, organizations, or industries (Davis and Caldeira 2010; Peters 2010). Due to the extensive attention given to the externalities of environmental issues, the discussion on carbon footprint has gradually risen to the level of national/regional cooperation (Hertwich and Peters 2009; Ivanova et al. 2017; Peters et al. 2011).

Although carbon footprint research has been relatively mature and complete, there is still a lack of detailed literature review and systematic summary. This is mainly reflected in three aspects: 1) There are relatively few review studies in the carbon footprint research (Lombardi et al. 2017; Wiedmann and Minx 2008); 2) Existing review studies tend to focus on elaborating the development status of carbon footprint in a certain research field or a region; 3) Existing review studies tend to be the literal interpretations of existing literature, and lack intuitive graphical context. Based on the research gaps, this study attempts to conduct a systematic review of carbon footprint research in the past 28 years based on knowledge graphs and bibliometrics. This not only helps to visualise the theoretical framework and knowledge system of carbon footprint research, but also promotes the phased development, and provides reference for related research. Based on the research motivation, this study intends to answer the following three main research questions: 1) What is the knowledge base of carbon footprint research? How does it affect thematic development? 2) What kind of cooperation network does the carbon footprint research have? What are the dimensions of this cooperation? 3) Do the knowledge and topics in carbon footprint research have a tendency to drift? How did this drift (if applicable) evolve? Based on the research topics and research questions, the following chapter arrangements are adopted: the research design, research tools, data retrieval process and preliminary data description are given in Chapter 2; the theme context analysis based on the co-citation analysis is explained in Chapter 3; the research cooperation network and its performance in three dimensions are arranged in Chapter 4; the knowledge evolution process based on co-words analysis and journal overlay analysis is then given; discussion of the results, limitations, and corresponding implication are then provided.