Does anyone know what 'on record' means for NOAA? EDIT: I found this from NOAA -> Earth’s long-term warming trend continued in 2018 as persistent warmth across

Does anyone know what 'on record' means for NOAA? EDIT: I found this from NOAA -> Earth’s long-term warming trend continued in 2018 as persistent warmth across large swaths of land and ocean resulted in the globe’s fourth hottest year in NOAA’s 139-year climate record. So the implication is that this is that maybe this is the wettest 12 months since 1879?