The Earth is warmer now than at any time since reliable record-keeping began in 1880, and we're continuing to warm at an accelerated rate. In fact, the Earth is warmer now than at any point in modern human civilization.
The context: 2017 was the third-warmest year on record, and the seven warmest years have occurred since 2010. This chart shows temperature anomalies — which is a departure from an average long-term baseline temperature — for every month since January 1880, compared to the average temperature between the years 1901 and 2000. The data is constructed from thousands of available, quality-controlled land and sea surface temperature readings across the world, and runs through May 2018.
Go deeper: Why climate change hits the poorest countries hardest.