Revisiting Allen's nitrogen hyphotesis from a climate perspective (1645-1740)

Building on Allen’s Nytrogen Hypothesis, this paper assesses the role of climate change in the English Agricultural Revolution. Our results show that, while Nitrogen-fixing plants, better cultivation and improved seeds explain half of the variation in yields, the changing climatic conditions characterizing the cooling period (1645-1715) and the subsequent warmer phase account for the remaining variation. Given that the colder and more humid climate existing during the second half of the 17th-century and early 18th-century negatively affected yields, farmers’ efforts during this period were even higher than what it is implied by the observed yields. Increasing temperatures in the next phase (starting c.1715), however, had a positive effect on agricultural productivity, so the role of the farmers in this stage has been previously over-rated.