See “Climate Hysteria: An Update” for the background of this post.
The average annual temperature in the city of Austin, Texas, rose by 3.7 degrees F between 1960 and 2019, that is, from 67.2 degrees to 70.9 degrees. The increase in Austin’s population from 187,000 in 1960 to 930,000 in 2019 accounts for all of the increase. (The population estimate for 2019 reflects a downward adjustment to compensate for an annexation in 1998 that significantly enlarged Austin’s territory and population.)
My estimate of the effect of Austin’s population increase on temperature is based on the equation for North American cities in T.R. Oke’s “City Size and the Urban Heat Island”. The equation (simplified for ease of reproduction) is
T’ = 2.96 log P – 6.41
T’ = change in temperature, degrees C
P = population, holding area constant
The author reports r-squared = 0.92 and SE = 0.7 degrees C (1.26 degrees F).
I plugged the values for Austin’s population in 1960 and 2019 into the equation, took the difference between the results, and converted that difference to degrees Fahrenheit, with this result: The effect of Austin’s population growth from 1960 to 2019 was to increase Austin’s temperature by 3.7 degrees F. What an amazing non-coincidence.