The economic circle around Beijing is a very important area that supports the development of Beijing-Tianjin-Hebei region in China. The economic growths of the economic circle around Beijing are deeply affected by the regional economic disparity. Besides the resources and environment problems, economic factors may be more prominent of regional sustainability. The objective of this paper is: (1) To find out what caused the regional economic disparity of Beijing-Tianjin-Hebei region; and (2) to assess the economic sustainable development status of the cities around Beijing, and give suggestions to narrow the regional disparity from the economic growth view. We used an assessment method based on the economic sustainable index system—the order relation method named G1 method, revised by standard deviation. The results showed that the fundamental reason for the differences lies in the disparity in production efficiency. The disparity in the regional economy increases the flow of talent to Beijing and Tianjin, so the labor productivity of Hebei Province will not improve. Thus, the economic gap among Hebei, Beijing, and Tianjin will continue to grow. This negative feedback will further exacerbate the economic growth problem. In terms of narrowing regional disparity, some implications are highlighted. Rational industrial structure, a high level of development in the manufacturing industry, and a high proportion of strategic emerging industries are important for the cities around Beijing to achieve high-level industry transfer, and the technological progress needed to promote economic growth.

The emission reduction targets articulated in the nationally determined contribution (NDC) reports of the “Belt and Road” countries, which have joined China in an international alliance to promote green development, are studied in this paper. Our findings indicate that the most commonly adopted emission reduction targets are relative to emissions in the base year and to baseline scenarios. Approximately half of these countries request technological and financial support from the international community in their NDC reports. Greenhouse gas inventory accounting, and data management, modeling, and tools are the most commonly identified technological needs. Moreover, the NDC reports indicate that $2.88 trillion of financial support is explicitly required, while a reliable international financial assistance and technology transfer would enable considerably higher emission reduction targets to be reached in Belt and Road countries. Our analysis of the top four emitters among these countries reveal a future decreasing trend for China and Russia and an increasing trend for India and Indonesia. China can effectively promote its Belt and Road green development initiative through measures such as capacity building in the areas of emission inventory accounting, constructing an “Internet Plus” platform for the use and management of low-carbon data, and technology exchanges aimed at strengthening low-carbon development.