In a 3-quart Dutch oven or kettle, melt butter over moderately-high heat. Add celery and onion and saute until just soft but not brown. Add carrots, potato, ginger and broth. Bring to a simmer, cover and cook until carrots and potato are soft, about 20 minutes.
In a food processor, working in 2-cup batches, place vegetable mixture and 1 cup half-and-half and puree until smooth.
Return to Dutch oven and add remaining half-and-half, corn, turmeric, paprika, white pepper, red pepper and salt. Cook, stirring over low heat until ingredients are heated through, about 3 minutes.