Global temperature anomalies, July 2023. This image shows the average land and sea surface temperatures in July 2023, compared to the 1951-1980 average for the same month. Areas that are hotter than normal are red, those that are cooler are blue. July 2023 was the hottest month since modern record-keeping began in 1880. This continues a long-term warming trend that has seen the past nine years being the warmest of the past 140 years. Scientists attribute this warming to increased carbon dioxide and other greenhouse gases in the atmosphere due to human activity.