Peel, halve lengthwise, and core pears. Combine water, sugar, cloves, and ground ginger in a large, deep skillet. Heat to simmering, then add the pears to the liquid. Cook, basting occasionally, until tender yet firm, about 10 minutes. Remove the pears. Increase heat to high. Boil the liquid until it is reduced and syrupy. Pour over the pears. Serve warm or chilled.