Who tweets climate change papers? investigating publics of research through users’ descriptions

knowledge economy [16, 45]. An account may represent an individual, a project, an organiza- tion, or a feed of content [46, 47]. The demographics of Twitter reflect those of the high-mid- dle class of the population, mostly white young professionals, although these demographics changes as we scale down to specific communities [48]. As for scholars, doctoral students and young researchers tend to be at the forefront, while some disciplines, mostly those dealing with social issues such as health sciences, economics or social sciences, are more visible [3, 49]. Our study focuses on the analysis of words and expressions in Twitter user bios as a proxy of who tweet climate change research papers since assessing who share scholarly documents at a larger scale entails reducing identity to specific markers [28, 46]. We hypothesize that the expressions employed by users to describe themselves act as identity markers through which they engage with other users [50]. Building on previous work on the identification of users sharing scholarly documents on Twitter, we identified 8 relevant categories of markers–acade- mia, communication, political, professionnal, personal, organizations, publishers, and bots–to classify who tweet climate change research papers [5, 16, 28, 51]. Methods that capture who engage with scholarly documents on Twitter usually rely on automatic textual analysis of Twitter bios [16, 28, 51–53] or manual coding [41, 54]. Altmetric also provides an identification of users in its database in four categories distinguishing between

researchers, science communicators, practitioners and general public [55]. However, their approach has limitations as it encompasses the “general public” as all the users who do not match to the first three categories. Other approaches relied on the characterization of the social network by which documents flow [16, 32, 54, 56]. Usually employed in conjuncture with tex- tual analysis of Twitter profile description, these methods aim to understand how discussions or communities build up around scholarly documents. More direct approaches rely on the matching of bibliometric information with Twitter data to capture the scholars involved on Twitter [57], as well as the use of Twitter lists [51, 58]. Our method build on these by investi- gating the categories of users sharing climate change research papers on Twitter through spe- cific expressions in Twitter profiles descriptions. As such, we account for the multiple identity markers used in a description to further assess the complexity through which someone may engage with research documents. We did not take into account the order in which these mark- ers appear as we wanted to have a general overview of how users present themselves without apposing any judgement on which identities are more important. Purpose of the study Profile description is often the primary information through which we assess someone else identity on Twitter [28]. As such, it is useful to assess someone else inclination toward specific topics on Twitter. Twitter bios also are a widely used proxy in informetrics studies to deter-

mine who are the users engaging in scholarly communication on Twitter [16, 28, 51–53]. As such, our study examines a categorization of users by analyzing specific keywords in Twitter descriptions. Our main objective is to look how much research papers about climate change issues per- meate outside of academia by examining the specific categories of users sharing said papers. As such, we focus our analysis on general categories of “markers” about users who may have an interest toward such research. We classify the descriptions of accounts who shared at least one link to a climate change research paper by linking them to the expressions collated for each category. Thus, we aim to assess the reach of scholarly documents in specific categories of users involved in the public communication of climate change research on Twitter: • RQ: Who share climate change research papers outside of academia? PLOS ONE Who tweets climate change research papers? PLOS ONE | https://doi.org/10.1371/journal.pone.0268999 June 3, 2022 4 / 17