This study uses a regional climate model (MM5) in combination with observed meteorological, satellite, and GIS data to determine the impact of urban forestry, living (green) roofs, and light-colored surfaces on near-surface air temperature and the urban heat island in New York City. Nine mitigation scenarios are evaluated city-wide and in six case study areas. Temperature impacts are calculated both on a per-unit area basis, as well as taking into account the available land area for implementation, and other physical constraints. The scenarios are then evaluated based on their cost-effectiveness at reducing air temperature and resulting energy demand. All the mitigation strategies have a significant temperature impact. A combined strategy that maximizes the amount of vegetation in New York City by planting trees along streets and in open spaces, as well as by building living (or green) roofs (i.e. ecological infrastructure), offers more potential cooling than any individual strategy. Among the single-strategy scenarios, light surfaces, light roofs, and living roofs can potentially reduce the summer peak electric load more than the other strategies. The choice of a strategy should consider the characteristics and priorities of the neighborhood, including benefit/cost factors and the available area for implementation of each strategy.