By Adoma Garu, Upper East Ghana — On a cracked field just outside town, 52-year-old Alhassan Naaba kneels beside wilted maize stalks and dusty groundnut vines. The rains, which usually begin in May, have barely come. His hopes for this year’s harvest — and his family’s survival — hang in the balance. “Last year, we harvested four bags,” he says, pointing to a dry stretch of earth. “This year, we may not get even one.” Across Ghana’s northern regions and parts of the savannah belt, climate change is hitting smallholder farmers hard. Rainfall is becoming less predictable, droughts are longer, and when the rain finally comes, it often arrives in…