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Assuming responsibility for emission reduction is an important part of participating in the global governance of climate change. Countries with a carbon neutrality target now cover about 75% of global greenhouse gas emissions. Carrying out fairness evaluations of their carbon neutrality targets provide a strong basis for the global carbon inventory. In this paper, the target years of carbon neutrality for major countries and regions under the global target of 2 °C and 1.5 °C are studied using the burden sharing model. On this basis, this paper simulates the possible pathways of carbon neutrality and evaluates the ambition of emission reduction targets in terms of annual emission reduction, per capita emission, and cumulative per capita emission. The results show that, from the perspective of equity, most of the developing countries cannot meet the global goal of 1.5 °C. The United States and the European Union nations could achieve carbon neutrality by 2050 by continuing their annual emission reductions under their existing NDC targets. However, to achieve carbon neutrality by 2060, China's annual emission reduction rate from 2030 to 2050 will be 6.7%, and the annual amount of emission reduction accounts for 51% of the global amount under the 1.5 °C target. Meanwhile, China would become the main force behind global cumulative emissions in the following decades. Thus, the emission reduction pathways China chooses will have an important impact on global climate mitigation progress. Based on the above research conclusions, this paper proposes that developed countries and developing countries should explore bilateral or multilateral cooperation in technology and finance in the field of climate change. Under the great pressure to achieve carbon neutrality, China needs to carry out research on the overall emission reduction pathways as soon as possible and clarify the paths at the scale of sectors, industries, provinces, and time stages. [ABSTRACT FROM AUTHOR]

Based on the assessment report of the Intergovernmental Panel on Climate Change (IPCC) and recent research literatures, from the perspective of the impacts and risks of climate change, this paper attempts to interpret several climate tipping points that may be exceeded due to global warming and explain mitigation measures such as carbon dioxide emission peak and carbon neutrality taken by the international community. The importance and urgency of adaptability research in different systems or regions are discussed. The main conclusions are as follows: ① In the past century, especially since the 1970s, global warming has been increasing rapidly, while the warming rate of China􀆳s land and sea is higher than that of the global average. ② In 2019, the atmosphere concentration of CO2, the main driver of global warming, has reached 410.5 ppm, which was 148% of the pre⁃industrial (1750) level and the highest at any time for at least 2 million years. ③ The risks of climate change will increase disproportionately as global temperature quickly increases. The climate tipping points (thresholds) of some systems may be exceeded or occur earlier than expected, causing abrupt and irreversible changes. ④ With the increase of global warming, nine global climate tipping points may being exceeded, including large⁃scale bleach⁃ ing and death of warm water coral reefs, accelerated melting of Greenland and Antarctic ice sheets, slowdown of the Atlantic Meridional Overturning circulation, etc., and there is also a risk of domino effect. ⑤ In order to address the impacts and risks of climate warming, it is necessary to limit global temperature rise in this century to 2 ℃ (preferably 1.5 ℃) above pre⁃industrial levels (1850-1900). Com⁃ pared with 2010, the global net anthropogenic CO2 emissions need to be reduced by about 25% (45%) by 2030 and achieve carbon neu⁃ trality in around 2070 (2050). ⑥ Taking warm water coral reefs as an example, this paper discusses and analyzes that the tipping point of damaged coral reefs in China may be firstly exceeded due to the high warming rate of the China Seas. Therefore, it is urgent to restore and strengthen the climate resilience of different systems or regions such as damaged coral reefs, so as to improve their ability to adapt to climate change. In addition, a breakthrough has recently been made in the research on in situ sexual reproduction and restoration of damaged coral reefs in China, which provides a positive prospect for reconstructing the resilience of damaged coral reefs. [ABSTRACT FROM AUTHOR]