Birge—Heat Budgets of American and European Lakes, 
193 
AND EUROPEAN LAKES. 
Winter Tempeia- 
ture, Tm w 
Summer Tempera¬ 
ture, Tm s . 
Tm s - 
-Tm w 
Annual 
Heat 
Budget 
Dm (Tm s 
—Tm w ) 
Calories 
Wind- d istributed 
Heat. 
Dm (TmS-4.) 
No. 
Date 
Value 
Date 
Value 
Year. 
Value 
Year 
Calories 
1910 VIII 20 
1911 IX 4 
11.07 
9.99 
10 
11 
27,500 
22,900 
1 
1911 
1113 
2.23 
1910 VIII11 
9.26 
10-11 
7.03 
38,300 
10 
28,600 
2 
1911 IX 2 
8.94 
11-11 
6.71 
36,600 
11 
26,900 
1910 VIII 18 
12.17 
24,900 
3 
1911 IX 5 
11.48 
22,800 
1911 
IT 5 
0.83 
1910 VIIT 13 
13.59 
10-11 
12.76 
37,400 
10 
28,100 
4 
1912 
III 1 
1.49 
1911 IX 3 
12.86 
11-11 
12.03 
35,200 
11 
26,000 
1912 IX 13 
13.93 
11-12 
11.37 
83,300 
12 
29,100 
12-12 
12.44 
36,400 
Mean 
357(500 
Mean 
277700 
1911 
II10 
3.39 
1910 VITI 5 
7.71 
10-11 
4.32 
38,300 
10 
32,900 
5 
1911 IX 1 
7.35 
11-11 
3.96 
35,100 
11 
29.700 
1911 
IT11 
1.10 
1910 VIII 14 
10.10 
10-11 
9.00 
39,200 
10 
26,600 
6 
1912 
III 7 
2.39 
1911 IX 3 
10.74 
11-11 
9.64 
41,900 
11 
29,300 
11-12 
8.35 
36,300 
Mean 
39,100 
1901 
I 25 
0.85 
1900 IX 8 
11.6 
00-01 
10.75 
35,600 
CO 
25,200 
7 
1906 
11 16 
1.31 
1905 VIII 20 
12.0 
05-06 
10.69 
35,400 
05 
26,500 
1911 
III 2 
2.13 
1906 VIII 14 
12.3 
06—06 
10.99 
36,400 
06 
27,500 
1912 
HI 18 
1.74 
1908 IX 3 
11.3 
10-11 
9.67 
32,000 
08 
24,200 
1913 
III 10 
1.86 
1909 VTTI 20 
12.1 
11-11 
9.77 
32,300 
09 
26,800 
1914 
III 8 
1.70 
1910 IX 1 
11.8 
11—12 
10.16 
33,600 
10 
26,000 
1911 VIL1 17 
11.9 
12—12 
10.26 
34,000 
11 
25,900 
1912 VIIT 15 
12.0 
12-13 
10.14 
33,500 
12 
26,500 
1913 VIII 21 
12.2 
13—13 
10.34 
34,200 
13 
27,100 
1914 VIII 12 
12.0 
13-14 
10.50 
32,800 
14 
26,500 
14—14 
10.30 
34,100 
Mean 
34,000 
Mean 
26,200 
1903 
II 24 
7.89 
1897 VII 29 
11.84 
03-03 
4.23 
33,000 
8 
1904 
III 14 
8.32 
1900 VII 20 
8.95 
03-04 
3.80 
29,600 
1906 
II 25 
7.00 
1903 VIII 28 
12.12 
04-04 
3.90 
30,400 
1904 VII18 
12.22 
06-06 
4.28 
33,400 
[ 
1906 VIII 25 
11.28 
Mean 
31,600 
1895 
II 16 
4.89 
1894 IX 9 
8.47 
94-95 
3.58 
25,400 
9 
1894 
ITI 4 
4.95 
1894 VIII10 
8.27 
94-94 
3.32 
26,900 
34,600 
10 
1895 
II 26 
3.70 
94-95 
4.57 
37,000 
13—S. A. 
