Temporal trends of environmental concern and potential influencing factors in the United States and China, 1945–2019

Past investigations into the temporal trends of environmental concern (EC) yielded varying results across different time spans and nations, highlighting the need for nation-specific studies with extended time frames. Using data from Google Ngram Viewer, this pre-registered study examined the temporal trends and influencing factors of EC as reflected in books published in the United States and China—the world's two largest greenhouse gas emitters—between 1945 and 2019. The findings revealed distinct patterns between the two countries. In the United States, EC rose sharply in the 1960s, peaked in the 1990s, and declined steeply thereafter, with local environmental problems emerging as the most stable predictor of this trend. In contrast, in China, EC has steadily increased since the 1980s, potentially driven by both local and global environmental problems as well as post-materialist values. These findings highlight that while EC trends and their potential determinants share commonalities across nations, they also exhibit unique characteristics. This underscores the importance of considering each society's distinct socio-historical context when examining the evolution of EC.