Heat the olive oil in a saucepan over medium heat. Add the onion and celery and saute for 5 minutes. Stir in the corn, thyme, and water and season with salt and pepper. Bring to a boil, reduce the heat and simmer for 15 minutes. Remove the thyme sprigs. Remove the soup in batches to a blender and puree until smooth. Strain the soup through a fine sieve. Season with salt and white pepper. Add slightly more salt than needed to compensate for the cold serving temperature. Cover and chill for 3 hours or longer. Divide the Crab and Avocado Salad between 6 chilled bowls. Arrange the salad in a ring in each bowl. Spoon the soup into the center. Garnish with chopped fresh chives, freshly ground white pepper and a drizzle of extra-virgin olive oil.
Crab and Avocado Salad:
Whisk the orange juice, lime juice, lemon juice, and olive oil in a bowl. Season with salt and white pepper. Fold in the crab meat and avocados. Adjust seasonings. Cover and chill.