Int. J. Environ. Res. Public Health 2020, 17, 1062 17 of 22
conducted to reveal the interactions between public discourse and natural, scientiﬁc, social, or political
events. In particular, factors promoting public consensus and factors resulting in discourse discrepancy
should be further identiﬁed to help climate communicators narrow the public cognitive divergence
about the global climate issue.
Supplementary Materials: The following are available online at http://www.mdpi.com/1660-4601/17/3/1062/s1.
Author Contributions: W.S. designed the study, collected the data, conducted the analysis, and wrote the article.
H.F. oﬀered suggestions to the part of temporal analysis. P .W. contributed to the hashtag co-occurrence part. C.C.
helped with the design of the study. J.X. contributed to the framing of the article and helped with the revision.
All authors have read and agreed to the published version of the manuscript.
Funding: This work was supported in part by the National Key R&D Program of China (Grant No.
2017YFA0604500), by the National Natural Science Foundation of China (Grant No. 51761135015, 71772142 and
U1839206), by the National Social Science Foundation of China (Grant No.18ZDA307), by the Center for High
Performance Computing and System Simulation, and by the Pilot National Laboratory for Marine Science and
Technology (Qingdao).
Conﬂicts of Interest: The authors declare no conﬂict of interest.
Appendix A
#agw, short for anthropogenic global warming, indicating global warming is caused by
human activities.
#cdnpoli, short for Canadian politics
#cop21, the yearly session of COP (short for the Conference of the Parties) held in 2015.
#cop24, the yearly session of COP (short for the Conference of the Parties) held in 2018.
#epa, short for the United States Environmental Protection Agency founded in 1970, an agency
aiming at protecting environment.
#gop, short for Grand Old Party, the Republican political party in the United States.
#nyc, short for New York City
#p2, short for Progressives 2.0, a hashtag used to show progressive political standpoints on Twitter.
#parisagreement, Paris Agreement, the agreement signed on UNFCCC in 2016 to deal with global
warming by reducing greenhouse gas emissions.
#sdgs, short for Sustainable Development Goals, containing 17 global goals put forward by the
United Nations General Assembly in 2015 and expected to be achieved in 2030.
#tcot, short for Top Conservatives On Twitter, a hashtag used to show conservative political
standpoints on Twitter.
#un, short for the United Nations
#us, short for the United States
References
1. Nisbet, M.C. Communicating climate change: Why frames matter for public engagement. Environ. Sci.
Policy Sustain. Dev. 2009, 51, 12–23. [CrossRef]
2. Roxburgh, N.; Guan, D.; Shin, K.J.; Rand, W.; Managi, S.; Lovelace, R.; Meng, J. Characterising climate change
discourse on social media during extreme weather events. Glob. Environ. Chang. 2019, 54, 50–60. [CrossRef]
3. Schuldt, J.P .; Konrath, S.H.; Schwarz, N. “Global warming” or “climate change”? Whether the planet is
warming depends on question wording. Public Opin. Q. 2011, 75, 115–124. [CrossRef]
4. Villar, A.; Krosnick, J.A. Global warming vs. climate change, taxes vs. prices: Does word choice matter?
Clim. Chang. 2011, 105, 1–12. [CrossRef]
5. Jang, S.M.; Hart, P .S. Polarized frames on “climate change” and “global warming” across countries and
states: Evidence from Twitter big data. Glob. Environ. Chang. 2015, 32, 11–17. [CrossRef]
6. United States Environmental Protection Agency. Climate Change: Basic Information. Available online:
https://19january2017snapshot.epa.gov/climatechange/climate-change-basic-information_.html (accessed on
10 October 2019).