Basil, beware using ‘about’ this or that, a technical professional forum. Also, do not assume that safety factors will take care of uncorrected data without evidence.
The term Landing Field Length (#1) is more often associated with manufacturers’ operational data in the QRH for use ‘in-flight’.
The landing distances associated with factoring originate from the certificated values in the AFM. As per MFS these distances are not corrected for temp.
The AFM ‘actual’ distances almost certainly cannot be achieved in routine operations.
Operational factors (i.e. EU-OPS) are applied to the AFM values for dispatch, but the resulting distances involve many assumptions, predominantly variation in flight path control, speed, and some environmental aspects, but not in combination; thus any distance margin should not be assumed to cover all cases, and in some may be very small.
The QRH ‘in-flight’ distances represent the manufactures ‘actual’ values and usually differ from those in the AFM; also they have different assumptions about flight path and speed control. Corrections and safety factors should be added to these because again the baseline distances might not be achievable in routine operations.
Interestingly both Airbus and Boeing QRH’s landing data have temp adjustments (e.g. Boeing 737, for max autobrake, approx +-100ft per 10C either side of ISA).
The Airbus table (OLD ? a/c type not known), only adjusts for temps above ISA.