title_body: How does the altitude at which beans are grown affect the final roast?
upvoted_answer: Based on the study entitled Effects of Altitude, Shade, Yield and Fertilization on Coffee Quality (Coffea arabica L. var. Caturra) produced in Agroforestry
  Systems of the Northern Central Zones of Nicaragua the summary describes following on the altitude subject:
  
  
    ...
    
    Altitude had the strongest influence on coffee physical
    characteristics, biochemical composition and organoleptic quality.
    Shade influenced significantly the physical characteristics and
    biochemical composition of coffee beans; nonetheless, the organoleptic
    quality was significantly enhanced by shade only in the altitudinal
    range of 950-1255 m. Fertilization and yield influenced positively
    physical characteristics of the coffee beans as well as their
    biochemical composition. The organoleptic quality was influenced by
    fertilization, but not by yield. Biochemical compounds showed strong
    relationships with organoleptic characteristics.