Since industrialization, human activities have dramatically altered atmospheric composition and land cover, with consequential impacts on climate. Between 1970-2021, the United States have been warming about 68% faster than the warming of the planet. Climate change increases the frequency and intensity of many types of weather extremes, with cascading effects. We will provide an overview of the new developments in physical climate science discussed in NCA5, explain the organizing framework, and discuss how the climate trends and Earth system processes chapters fit into the overall report.