10-Formyltetrahydrofolate

Airport reference temperature is defined as the monthly mean of average daily temperature (T_a) for the hottest month of the year plus one-third the difference of this temperature (T_a) and the monthly mean of the maximum daily temperature (T_m) for the same month of the year.

Thus airport reference temperature is

$T_{a}+{\frac {T_{m}-T_{a}}{3}}.$

References

• Airport Engineering by Norman J. Ashford and Paul H. Wright, 3d edition, page 234. [1]