So rather than having a true Tavg the night
marine air temp is really a proxy for Tmin.
Night time
marine air temp NMAT is effectively a proxy for tas Tmin, not Tavg.
Nick, I understand that
marine air temp is taken at night to avoid radiant day heat reflecting from the ship, but there was not much information I could find to see if the time of observation had a protocol and whether it was consistently followed.
Not exact matches
By using night
marine air temperatures to normalize all sea data Huang effectively transferred the tas tend to tos for ERSSTv4 (NOAA's ocean
temp index used by GISTEMP).