Climate Change and Urban Forests
Urban forests include developed sites adjacent to streets and buildings, parks, residential areas, and schools, as well as natural areas designated as preserves and large urban wooded areas.
Urban forestry can be an important mechanism for increasing stored carbon as trees in urban areas can have significant biomass and carbon sequestration (Nowak et al. 2013). Carbon sequestration rates in individual trees within urban areas can exceed those in natural forests due to greater foliar biomass and reduced competition from lower tree densities, as well as irrigation and fertilization (Jo and McPherson 1995)—and a changing climate may be further accelerating these growth rates in urban areas (O’Brien et al. 2012; Pretzsch et al. 2017). Trees can have an additional important influence on carbon mitigation in urban zones by reducing the energy requirements for building heating in winter due to wind protection and summer cooling from tree shading (Nowak et al. 2010).
Examples of adaptation tactics are:
“Greening” areas that currently have low canopy cover by adding street trees and other vegetation
Strategic planting of trees to provide building shading or cooling benefits
Creation of parks and green spaces on abandoned or underutilized spaces, such as brownfields
Integration of trees as part of low-impact development or stormwater runoff projects
Trees can remove CO2 and greenhouse gases from the atmosphere. Planting more trees in cities can help mitigate the effects of climate change but the emissions of CO2 and greenhouse gases also need to be reduced.
Scientists agree that we can best put the brakes on climate change by doing two things.
Immediately cutting back carbon emissions.
Developing a workable system for pulling excess carbon from the atmosphere using currently available technology. The most realistic approach appears to be the planting of more trees.