logical. Should missing values (including NaN) be removed?
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Value
n0to10
Formula
$$MOI=\frac {0.731 \phi +1.767}{Thm-Tcm}$$ $$\phi$$ = geographical latitude; Thm = Average temperature of the hottest month (Celsius); Tcm = Average temperature of the coldest month (Celsius)
References
Marsz A, Rakusa-Suszczewskis S. 1987. Charakterystyka ekologiczna rejonu Zatoki Admiralicji (King George Island, SouthShetland Islands). 1. Klimat i obszary wolne od lodu.Kosmos36:103<U+2013>127.