After speaking in the previous verse of the heavens and the earth as agents of drought and famine, respectively, the Lord uses the first-person pronoun (where he is the subject) to draw the reader (including the first readers) back to the realization that he himself is speaking here, and is the ultimate cause behind the covenant curses.1
11 And I have called for a drought on the land and the hills, on the grain, the new wine, the oil, on what the ground brings forth, on man and beast, and on all their labors.”