Three of the world’s most complete temperature tracking records – from NASA’s Goddard Institute for Space Studies, the National Oceanic and Atmospheric Administration’s National Climactic Data Center and the UK Meteorological Office’s Hadley Centre – begin in 1880. Prior to 1880, temperature measurements were made with instruments like thermometers. The oldest continuous temperature record is the Central England Temperature Data Series, which began in 1659, and the Hadley Centre has some measurements beginning in 1850, but there are too few data before 1880 for scientists to estimate average temperatures for the entire planet.