Scientists reached the new figure by looking again at remote satellite readings of temperatures on the East Antarctic Plateau, which covers the South Pole, and recalibrating these readings with updated data taken from weather stations on the ground.
The area in question is the East Antarctic Plateau, a huge, empty expanse the size of Australia that starts right near the South Pole.
In 1983, a Russian weather station measured a record-low air temperature of -89° C (-128° F) there, and in 2013 satellite data revealed certain pockets could get as cold as -93° C (-135° F).
When the researchers first announced they had found the coldest temperatures on Earth five years ago, they determined that persistent clear skies and light winds are required for temperatures to dip this low. Any water vapour in the air tends to heat it up, albeit slightly. Because cold air is dense, it funnels into the dips where it may stay trapped for several days when skies are clear and winds are light.
"There's a limit to how long the conditions persist to allow it to cool to these ultra-low temperatures, and a limit to how much heat you can actually get through the atmosphere, because water vapor has to be nearly nonexistent in order to emit heat from the surface at these temperatures", Scambos said in a statement.
Just how cold can it get on Earth? To go any lower, they would have to persist for several weeks, which is extremely unlikely, according to the scientists. High altitude and a close proximity to the South Pole make this region the most favorable location for extreme cold of this magnitude.
Vostok, Antarctica, now holds the world record for the coldest temperature ever recorded by a land-based weather station.
Since it is impossible to install a weather station in the area, Scambos and his team looked at satellite data from 2003 to 2016 to see just how cold it got in the area.
In the new study, they analyzed satellite data collected during the Southern Hemisphere's winter between 2004 and 2016.
The researchers clarify that new data on low temperature were obtained with a few satellites: Terra and Aqua space Agency NASA, as well as several satellites of the National oceanic and atmospheric administration (USA). Herrera says that the previous high-minimum temperature record for any 24-hour period was 41.9°C (107.4°F), set at nearby Khassab Airport in Oman on June 27, 2011. This gives the researchers a better idea of the surface temperature at the time in Antarctica.
The new low point is officially minus 98 degrees Celsius (minus 144 degrees Fahrenheit), a temperature that "appears to be about as low as it is possible to reach" according to the global team of researchers who worked on the new study.
That got the study authors wondering: is there a limit to how cold it can get on the plateau?
Thinking about the very same ultra-low temperature level was videotaped in numerous areas throughout the glacier, also numerous thousands of kilometres or miles apart, the researchers believe this could be as cool as it's feasible to obtain in the world. The obvious explanation is that this is, in fact, the coldest it can get on the plateau.