text: As the climate change and global warming discourses evolved over the past years, their relative 
  statuses in public discourse also changed. Although from 2009 to 2018, increasing numbers of people 
  started to use Twitter, resulting in an overall rise in the number of tweets and hashtags, the ratio of 
  #climatechange frequency and #globalwarming frequency still indicated the public’s change in frame 
  preference. Figure 1a displays that in 2009, the number of tweets with #climatechange was 2.69 times 
  that of the tweets with #globalwarming, whereas the ratio signiﬁcantly since 2013 and reached 13.02 
  in 2018. The climate change network showed a stronger ability to incorporate diverse hashtags into 
  discussions, according to Figure 1b. In 2009, the hashtags that co-occurred with #climatechange were 
  2.44 times those that co-occurred with #globalwarming, and the ratio climbed to 6.36 in 2018. 
  
  The rank–order correlation coeﬃcient of nodes between the two networks maintained a stable 
  level and showed a slight climbing trend starting 2009, as shown in Figure 6a, except for 2010 and 
  2011, when the p-values were larger than 0.05 and no signiﬁcant correlations were identiﬁed. The QAP 
  analysis showed that the associations between the two discourses were correlated in the 10-year period 
  (the p-value for 2015 was 0.011; p-values for all the other years were less than 0.001). Figure 6b reveals 
  that the similarity of associations between the top 50 nodes in the two discourses ﬂuctuated and did 
  not show a rising trend with the correlation of nodes’ rank order. 