A new study using satellite data from 2001 to 2022 compared how vegetation in 751 cities worldwide responded to climate pressures like extreme heat. The results surprised the researchers: in over three-quarters of those cities, plant life coped better than greenery in the surrounding countryside. In one-third of municipalities, urban trees showed a "dual advantage," losing less greenness under stress and recovering faster afterward.
The lead author, ecologist Zhengfei Guo of the University of Hong Kong, said the findings were unexpected because urban environments are generally harsher for vegetation, with higher air temperatures and more pollution. The likely explanation, the researchers say, is water. City trees are often deliberately irrigated by parks departments or residents, and the built environment itself directs rainwater off pavement and into soil patches where trees can absorb it.
This pampering gives urban vegetation an edge during droughts and heat waves, while rural trees are left to fend for themselves. The resilience matters because healthy city trees provide shade, support biodiversity, and help absorb rainwater that might otherwise cause flooding. Eric North, program manager for urban forestry at the Arbor Day Foundation, who was not involved in the study, said the resilience likely stems from "intentional management from people, or just the way we've simply designed cities to move and work."