When Cities Threaten Their Forests, Their Cities Are Imperiled


Just in time for Arbor Day, researchers from Yale and Ohio State Universities have released a study that quantifies and compares to some degree the impact of urban forest loss on climate change. Together, the study’s authors found that large-scale woodland management strategies can protect cities from damages caused by atmospheric carbon emissions and from lower air quality, by halting the ongoing dramatic degradation of the urban forest.

Urban forest managers may be able to mitigate and, in many cases, reverse the rate of urban forest loss, the study’s authors concluded. In addition to the health benefits urban forests could give city dwellers, the benefits could include helping cities reduce the effects of climate change.

The new study estimates the effect of carbon emissions from outdoor burning and winter heating, the decline in tree canopy cover, and the air quality effects of urban forests on each of four variables: mean temperature, mean cloudiness, mean ozone, and mean air particle concentration. Each measure is associated with an overall effect of urban forest management on the four variables of precipitation, temperature, and air pollution. The study also found that large-scale forestry strategies in the same regions as already successful projects are not only cost-effective but could eliminate deforestation in the same areas.

The same study calculated the effect of forest conservation projects on water use. In low-income urban districts with better forest cover, water use will be decreased by 16 percent. In urban districts with reduced tree canopy, water use will be increased by 19 percent.

Municipalities could take steps toward forest conservation by re-foresting vacant lots, replanting trees, removing urban heat islands, and ensuring that trees don’t stand in the way of stormwater drainage.

Read the full study at EnvironmentalProceedings.org.

Leave a Comment