Trees can be added to most urban landscapes without increasing water use, if trees or some combination of trees, shrubs, and ground cover replace lawn. Trees Affect Air Movement . Trees can help direct air movement. They can block undesirable winds, serve as windbreaks to slow the rate of the wind, deflect wind away from specific areas, and guide winds to help with cooling in summer months. Trees Reduce Air Temperatures .
Trees help moderate air temperature extremes.
Buildings and pavement absorb 90-95 percent of incoming radiation. Most of it is dispersed as heat, but the remainder is held in concrete and buildings and then is radiated back to the air at night. Trees, with the right vegetation, can block up to 95 percent of the incoming radiation. Trees will intercept up to 90 percent of summer solar energy and provide large reductions in interior temperatures. Trees and shrubs planted next to a home can reduce summer air-conditioning costs by 40 percent.