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studies have noticed that the Maya inscription about doomsday, which seemed rather ridiculous for
scientists, might lead to unexpected public associations with climate issues. However, science ﬁction
may inﬂuence the public’s attitude toward scientiﬁc issues. Frankenstein’s monster, a well-known
ﬁctional character who was a human-built creature in the novel written by Mary Shelley, has long been
linked to transgenic technology by referring genetically-modiﬁed food as “Frankenstein Food” [98].
Scientists found that these associations successfully symbolized the the public’s uncertainty about the
risk of transgenic technology, anxiety toward the human-made living creature, and moral discomfort
about reducing life to genetic code [99], even though people all know Frankenstein was only a ﬁctional
character created 100 years ago. In the current study, we concludd that a similar mechanism may exist
in global warming communication. Though “the end of world in 2012” and its adapted popular movie
sounded unconvincing for scientists, the public, especially who have limited scientiﬁc literacy, were
defenceless against ﬁction [ 100]. Some of the public may accept the indications of temperature rise and
extreme weather, and cannot help but strengthen their associations with global warming. However, no
similar associations were discovered in the climate change discourse in 2012, which may suggest that
global warming is more likely to be associated with disasters, risk, or negative sentiment compared
with climate change.
5.3. Discrepancy between the Two Discourses
The status of the two discourses varied signiﬁcantly in the more recent years in the study period.
Data from Google in prior study suggested that the search record for global warming was larger
than that of climate change in earlier times [13]. The authors found that in the battle to be the most
representative hashtag for global climate concern, #climatechange showed growing popularity and
became an overwhelming trending topic compared with #globalwarming. Also, #climatechange
showed a stronger ability to incorporate diverse hashtags into its discourse in both relative and absolute
dimensions. Comparatively, the popularity of the global warming discourse among social media
users did not increase apparently in terms of tweets volume and hashtag diversity, especially when
considering the yearly increase in Twitter users. The reason for the observed shift in public discourse
toward climate change from global warming may be attributed to the high exposure of climate change
in the media and scientiﬁc reports in recent years [13]. Previous studies noted that perceived scientiﬁc
consensus can increase acceptance of science [101]. Though global warming has been commonly used
since the 1980s to describe the world-wide temperature rise, climate change is preferred by scientists to
refer a range of complex changes of climate [102]. Pew found science-related accounts draw millions
of followers on Facebook and volume of posts they released climbed in past years [ 103]. Climate
scientists are found to be opinion makers on Twitter [104]. As social media has become an emerging
platform for science popularization, scientiﬁc community might contribute to the prevalence of climate
change discourse by talking about climate change facts and mitigating measures [75].
However, diﬀerences between two discourses were not eliminated. Even though two discourses
showed more similarities in the rank order of key concepts, the QAP analysis of two matrices of
semantic network showed that two discourses still embody distinct public perceptions of climate issues
by associating these hashtags in diﬀerent manners.
To be speciﬁc, although “ipcc”, “cop”, and “un” were mentioned in both discourses (yellow
in Figures 3 and 4) in earlier years, the clusters to which they belonged had signiﬁcantly di ﬀerent