Commentary Purg I 121-123

That is, once they had gotten closer to the sea, where the maritime breeze protects the dew from the heat of the sun more than it does higher up the slope.  There is debate over whether Dante meant to say 'ad orezza' or 'adorezza'; the second reading would translate as 'where there is shadow,' but most contemporary students of the problem have gone back to the early commentators' reading of the line, where 'orezza' is a diminutive of the noun 'ora' when it has the meaning of 'breeze.'