This report investigates the environmental system and climate change, focusing on the 21st Conference of Parties (COP21) and the Paris Agreement. It examines the goal of deep decarbonization by 2070 to limit global warming to 2 degrees Celsius. The report analyzes carbon emission reduction strategies, scientific evidence of climate change, and the impacts of energy consumption on environmental systems. It explores scientific data emission evaluation, stabilization scenarios, and the relationship between carbon emissions and global temperature rise. The report also examines decarbonization progress in G7 countries, comparing their policies and emission reduction stages. Furthermore, it delves into the analysis of historical climate change data, including baseline temperatures and excess mortality, to assess the effects of different warming scenarios. The findings highlight the importance of political actions, cumulative carbonization, and international collaboration in mitigating climate change.