Record-breaking heat waves made 2023 the hottest summer in the last 2000 years. Experts say that such terribly hot summers will continue if people do not stop polluting the air and causing climatic changes. Since 1850, weathermen checked rings of tree trunks to learn about the climate and made records of the same. Scientists checked the rings of 10,000 trees and found that 2023 was the hottest in 2000 years.