“I have now accepted the record at Maniitsoq based on further analysis,” Cappelen said.
At issue was whether the temperature measurement, taken at an airport location, was legitimate. Artificial heat sources at airports can sometimes corrupt temperature readings.
“We were faced with two options,” Coppelen explained. “We could reject the observation, or we could approve it. If we chose to overrule it, it could be based on two things. One was a faulty sensor/station…and that was not the question – the sensor measured exactly as it should. The second was if we had suspected that extreme local conditions played their part. Here the situation is more debatable, because the station is an airport station that is not necessarily completely optimal in relation to international guidelines for climatological data measurements.”
But Coppelen said the mere fact the temperature was recorded at an airport is not a reason for it be thrown out as few existing weather observing stations in Greenland are ideally sited.
“Within the World Meteorological Organization (WMO) prescribed practices, among other things, measurements – as an example – should be taken over a short lawn,” Coppelen said. “This can be done in Denmark almost anywhere, but in Greenland almost no places.”
Coppelen concluded: “The station in Maniitsoq is within the quality frame practicable/possible for this type of meteorological measurements in Greenland, so it is approved. Alternative would be to question many observations and weather records for Greenland…it doesn’t make sense.”
Hotter reading logged in Greenland before modern records began
Although the 78.6F reading measured at Maniitsoq is the warmest in the modern record, which began in 1958, historical weather records indicate Greenland has been hotter than that.
“23 June 1915 Ivigtut (old spelling) registered a maximum temperature of 30.1 deg C [86F]. It is printed in a [Danish Meteorological Institute] yearbook for 1915 and properly also in other publications,” Coppelen said.