TABLE 823.— TEMPERATURE VARIATION WITH DEPTH 



727 



Table illustrates temperature changes underground at moderate depths due to surface 

 warming (read from plot for Tiflis, Lehrbuch der Meteorologie, Hann and Siiring, 1915). 

 Below 20-30 m (nearer the surface in Tropics) there is no annual variation. Increase 

 downward at greater depths, 0.03 ± °C per m (1° per 35 m) 1. c. At Pittsburgh, 1524 m, 

 49.4°, .0294 per m; Oberschlesien, 2003 m, 70°, .0294 per m; or West Virginia, 2200 m; 

 70°, .034° per m (Van Orstrand). Mean value outflow heat from earth's center, 0.00000172 

 g cal cm" 2 sec" 1 , or 54 g cal cm" 2 yr~ l (39 Laby). Open ocean temperatures: Greatest 

 mean annual range (Schott) 40° N., 4.2°C; 30° S., 5.1° ; but 10° N., only 2.2° ; 50° S., 2.9? 

 Mean surface temp, whole ocean (Kriimmel) 17.4°; all depths, 3.9:. Below 1 km nearly 

 isothermal with depth. In Tropics, surface 28° ; at 183 m, 11°, 80 percent water less than 

 4.4°. Deep-sea (bottom) temps, range — 0.5° to +2.6°. Soundings in South Atlantic: 

 km, 18.9° ; .25 km. 15° ; .5 km, 8.3° ; 1 km, 3.3° ; 3 km, 1.7° ; 4.5 km, 0.6°. 



Sunspot number = k (10 X number of groups and single spots observed + total number 

 of spots in groups and single spots), k depends on observer and telescope, equaling unity 

 for Wolf with 3-in. telescope and power of 64. Wolf's numbers are closely proportional 

 to spotted area on sun, 100 corresponds to about 1/600 of visible disk covered (umbras 

 and penumbras). Periodicity: successive outbursts about 11 years apart, extremes 7.3 

 years and 17.1 years. See references for daily and monthly values. 



Smoothed monthly numbers are formed from monthly means of observed number by 

 weighting the sixth months preceding and following 1, all 11 intervening months 2. 



Smoothed monthly sunspot numbers, annual means 



Maximum and minimum values for period in boldface 



Year 



1750 

 1760 

 1770 

 1780 

 1790 

 1800 

 1810 

 1820 

 1830 

 1840 

 1850 

 1860 

 •1870 

 1880 

 1890 

 1900 

 1910 

 1920 

 1930 

 1940 

 1950 



o 

 83.1 



64.7 



98.5 



89.2 



90.6 



15.0 



.0 



16.6 



67.2 



61.9 



69.8 



94.3 



131.8 



31.6 



8.4 



8.8 



21.0 



36.9 



38.8 



66.8 



l 

 52.2 

 80.2 



86.7 



66.5 



67.6 



33.7 



1.7 



6.6 



50.5 



38.5 



63.2 



77.7 



113.8 



54.4 



37.7 



3.4 



6.5 



27.0 



21.1 



50.5 



45.9 

 60.1 

 65.7 

 38.7 

 59.8 

 44.1 

 4.5 

 4.0 

 26.3 

 23.0 

 52.8 

 61.1 

 99.7 

 58.1 

 70.0 

 5.7 

 3.4 

 13.0 

 12.1 

 30.3 



28.9 



48.5 



39.7 



22.5 



47.3 



43.0 



12.1 



2.6 



9.4 



13.2 



38.6 



45.4 



67.9 



65.4 



83.7 



23.0 



2.2 



6.3 



5.9 



15.3 



4 



13.5 

 36.7 

 27.5 

 10.3 

 38.5 

 46.8 

 15.5 



8.3 

 13.3 

 17.7 

 21.0 

 45.2 

 43.1 

 63.3 

 79.1 

 44.1 

 11.8 

 16.8 



9.4 

 11.1 



5 

 9.3 



21.4 

 8.8 



26.7 

 24.0 

 42.5 

 35.1 

 16.9 

 59.1 

 38.4 

 7.7 

 31.4 

 18.9 

 51.3 

 61.5 

 58.7 

 46.4 

 43.7 

 36.5 

 36.4 



6 



12.2 

 14.2 



21.7 

 81.2 

 15.6 

 27.3 

 46.1 

 35.3 

 121.1 

 59.7 

 5.2 

 14.7 

 11.7 

 25.1 

 43.1 

 60.3 

 59.1 

 66.5 

 79.6 

 91.7 



7 



31.9 

 35.9 

 92.2 



128.2 



6.5 



11.6 



39.8 



51.6 



137.0 

 97.3 

 23.0 

 8.8 

 11.0 

 12.6 

 28.1 

 56.0 

 96.2 

 70.0 



113.2 



145.6 



8 



47.2 



66.8 



151.3 



133.3 



4.6 



7.6 



30.0 



62.1 



103.4 



125.0 



56.3 



36.9 



3.9 



7.0 



24.6 



51.2 



83.1 



74.5 



103.9 



141.2 



9 



54.5 

 103.4 



123.4 



117.0 



6.9 



3.1 



23.4 



67.1 



83.4 



95-4 



90.3 



78.6 



7.7 



6.3 



13.8 



40.6 



65.5 



62.0 



89.6 



134.7 



83.9 69.4 



* Prepared hy Allan F. Cook II. , ,_ ,,.„ ,,, ,, • _ >r 



■"Astron. Mitt. Zurich, No. 145. 1945; Tourn. Geophys. Res., vol. 54. p. 347. 1949; Walcimc jier , M, 

 Astron. Mitt Zurich; Terr. Ma?.; Tourn Geophys. Res., Trans. Int. Astron.. I mon Quart. Bull bolar 

 Activity; American Sunspot Number Reductions, Central Radio Propagation Laboratory, National 

 Bureau of Standards. 



SMITHSONIAN PHYSICAL TABLES 



