FAQ: Why do you use the 20th - century average for baseline for the statistics and rankings, but use 1981 - 2010 for the maps? (climate.gov)
The average annual rate of global sea level rise accelerated from 1993 - 2008, increasing 65 - 90 percent above the twentieth century average. (ucsusa.org)
The month was the 33rd warmest June for the U.S. as a whole, with average temperature 1.1 °F above the 20th century average of 68.5 °F. (scientificamerican.com)