Good question !!
The advent of the initial Ind. Rev. began in the late 1700's, primarily in the UK, and spread rapidly into western Europe, & US . 

However the rest of the world changed little. So any climate impact be more concentrated, and one would expect a rise in annual temperatures the UK & W. Europe. Below is a graph of two of the longest recorded temperature sets. 

The CET is from central UK, while the DeBilt is from the Netherlands, both starting prior to, & in the heart of the Ind. Rev. 

  http://www.4shared.com/photo/C6ML9O7zce/CET-DeBuilt_Temp.html

While the two set track each other pretty well, and show NO increase trend from the late 1700's to the late 1900's. And even the bump in the late 1990's+, was about the same as one in the early 1700's. 

UN population estimates show a significant population growth after the 1920's, but again the temperature graph does not show any significant trend change, at that time period.

So where is the human fingerprint?