Instrumental temperature record
The instrumental temperature record shows fluctuations of the temperature of earth's climate system. Initially the instrumental temperature record only documented land and sea surface temperature, but in recent decades instruments have also begun recording ocean temperature. Data is collected from thousands of meteorological stations around the globe and through satellite observations. The longest-running temperature record is the Central England temperature data series, that starts in 1659. The longest-running quasi-global record starts in 1850.