There are a number of major scientific institutions around the world that keep track of the Earth’s temperature and one is proving to be very accurate, NASA.
Every year, NASA partners with the NOAA and they’ve concluded that 2018 was the fourth-warmest year on record and that 2016 was the warmest.
They use temperature data dating back to 1880, so just how accurate is it? Within 1/20th a degree Celsius.
Source: https://www.sciencealert.com/nasa-s-long-term-climate-predictions-are-accurate-to-within-1-20th-of-a-degree
