Freeze-thaw degree-day indices were com- 
puted by the standard technique of summing the 
daily departure from O°C. Progression of season- 
al soil thaw was determined by Bilgin (1975) for 
the summer of 1972 using a probing technique. 
Soil temperatures were also recorded in 1972 on 
Grant recorders for a polygon area north of Pad 
F, and the data reduced at 3-hour intervals. 
Results 
Table 2 presents the mean monthly and 
annual temperature data for Barrow, Prudhoe, 
and Barter Island. Prudhoe clearly has warmer 
summers and colder winters than either Barrow 
or Barter Island. The effect of continentality 
only a few kilometers inland from the ocean is 
exemplified by the Prudhoe data and, as will be 
shown, the effect becomes rapidly more 
pronounced further inland. 
As shown in Table 2, the annual temperature 
regimes at Prudhoe paralleled those of Barrow 
and Barter Island in terms of individual warm 
and cold seasons as well as annual averages. 
Annual averages for both 1970 and 1971 were 
cooler than 1972 and 1973 across the entire 
coastal plain. The variations from year to year of 
Prudhoe temperatures are further demonstrated 
Table 3 
Maximum and minimum monthly temperatures (°C) for 
January and July at Prudhoe (1970-1973) 
January July 
Year Max. Min. Max. Min. 
1973 -22.6 =Sile3 11.1 2.4 
1972 -26.3 -32.6 10.6 2.1 
1971 -28.5 -37.3 Wiles: Sal 
1970 -24.7 -30.5 9.2 1.6 
in Table 3, based on January and July mean 
monthly maximum and minimum values. 
It is observed in Table 4 that the most 
notable differences between the coastal stations, 
Barrow and Barter Island, and the inland sta- 
tions, Prudhoe and Happy Valley, are in the 
summer warmth. Even comparing the coolest 
summers at the inland stations with the warmest 
summers of the coastal stations, the summer 
degree-day accumulations for the interior sta- 
tions are consistently greater. The coldest win- 
ters at Barrow, on the other hand, can be as cold 
as or even colder than the inland stations. This is 
undoubtedly due to the presence of the ice 
cover which, in effect, creates a more continen- 
tal climatic situation for the coastal stations 
during the winter. 
Barrow 
Point McIntyre 
Barter Island 
Prudhoe 
16 km south 
Happy Valley 
Barrow 
Point McIntyre 
Barter Island 
Prudhoe 
Happy Valley 
Table 4 
Comparison of mean monthly temperatures and thawing 
degree-days (°C) at coastal and inland stations. 
Mean Monthly Temperatures and Thaw Degree-Days 
June July Aug Total Thaw Degree-Days 
1972 
0.3 (9) 6.1 (189) 4.8 (148) 346 
0.3 (9) 3.9 (120) 4.6 (142) 271 
1.2 (36) 4.1 (127) 5.2 (161) 324 
2.7 (81) 6.3 (195) 5.7 (176) 452 
2.5 (75) 7.3 (226) 6.5 (201) 502 
8.1 (243) 12.6 (390) 9.8 (303) 936 
1973 
0.7 (21) 4.3 (133) 4.3 (133) 286 
O7A(2iio) 4.5 (139) 4.6 (133) 254 
1.2 (36) 4.9 (151) 4.3 (133) 320 
2.2 (66) 6.8 (210) 6.4 (198) 474 
8.7 (261) 12.2 (378) 7.5 (232) 871 
*Partial months (12-30 June; 1-24 August) 
