Global temperature anomalies, July 2023. This chart shows the global temperature anomalies for every July from 1880 to 2023. Julys that were hotter than normal are red, those that were cooler are blue. July 2023 was the hottest July, and month, since modern record-keeping began. 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.