Trees and other plants have a natural cooling effect, so greenery is a simple and effective way to reduce the heat island effect. <\/b><\/p>\n
In the first of a series of articles, we explore what else trees can offer us in addition to their direct cooling effect,
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\n3, we will find out how local government and the local community can support these processes. <\/b><\/p>\nThe benefits of trees and vegetation<\/h4>\n
Trees and vegetation in the urban environment cool the environment, but they also provide a range of so-called ecosystem services.<\/p>\n<\/div><\/div><\/div><\/div><\/div>
How do trees and vegetation reduce temperatures?<\/h4>\n
Trees and vegetation (e.g. shrubs, bushes, tall grasses) reduce surface and air temperatures by shading and cooling through evaporation. In addition to reducing temperatures, trees and other plants provide a number of additional benefits.<\/p>\n<\/div> Reduce energy use and ensure lower greenhouse gas emissions<\/b><\/p>\n Trees and vegetation that directly shade buildings reduce the need for air conditioning. Improving air quality <\/b><\/p>\n Airborne pollutants are deposited on the leaves of trees, directly removing them from the air. They help retain rainwater and improve water quality <\/b><\/p>\n Trees and vegetation support water quality in three ways: <\/p>\n – First, they absorb excess rainfall, reducing the amount of water that runs off roofs and streets into the sewer system. – Second, trees and vegetation filter fertilisers, pesticides, animal waste and other pollutants that could easily enter drains and open water from paved surfaces if they do not. <\/p>\n – Thirdly, trees provide shade, which cools down run-off water and prevents water temperature shocks to aquatic life.<\/p>\n<\/div><\/li> They also contribute to a better quality of life and reduce social inequalities<\/b><\/p>\n Studies show<\/a> that connecting with nature reduces heart rate and high blood pressure, and boosts immune function. US data show that certain population groups are disproportionately affected by extreme heat, including minority populations and low-income people. Providing habitat for wildlife, increasing biodiversity<\/b><\/p>\n Trees and other plants provide essential habitat and food for many species, including pollinating insects, migratory birds and small mammals (e.g. bats, squirrels).
\nEvaporation is the process by which vegetation absorbs water through its roots and then evaporates it through its leaves.
\nEvapotranspiration essentially cools by using the heat of the air to evaporate water.
\nThis cooling effect also affects the surrounding soil, and is also used to evaporate precipitation falling on the leaves of the vegetation.
\nAccording to a scientific paper<\/a> reviewing 308 studies, urban forests are on average 1.6\u00b0C cooler than non-green areas. <\/p>\n<\/div><\/div><\/div>![](\"https:\/\/varosieso.hu\/wp-content\/uploads\/2024\/08\/Kepernyokep-2024-08-25-084101.jpg\" "\\"K\u00e9perny\u0151k\u00e9p")
<\/span><\/div><\/div><\/div><\/div><\/div>The co-benefits of trees<\/h4>\n
\nGreen infrastructure, including urban parks and forests, can reduce the energy demand of nearby buildings<\/a> by up to 10 percent.
\nThis in turn reduces greenhouse gas emissions from fossil fuel energy production, contributing to climate change mitigation.
\nTrees also directly store and sequester carbon dioxide from the air through the process of photosynthesis. <\/p>\n<\/div><\/li>
\nThese include particulate matter (PM), nitrogen oxides (NOX), sulphur dioxide (SO2), carbon monoxide (CO) and ground-level ozone (O3).
\nTall and dense roadside vegetation can reduce air pollutants by<\/a> about 30%.<\/a>
\nTrees also indirectly improve air quality by reducing energy use and pollution from fossil fuel power generation. <\/p>\n<\/div><\/li>
\n By absorbing between 15 and 27% of<\/a> annual rainfall ,<\/a> urban trees can reduce the amount of water entering the sewer system.<\/a> <\/p>\n
\nIncreasing tree cover reduces<\/a> the risk of heat-related illnesses<\/a> such as heat stroke.
\nThus tree cover in urban areas leads to a reduction in heat-related deaths. One analysis estimated that<\/a> a 10% increase in tree cover would result in about 50 fewer deaths per year in Salt Lake City, Utah, and 3,800 fewer in New York City.
\nIn addition, trees and vegetation act as a physical barrier to reduce noise and light pollution. <\/p>\n
\nResearch shows that these associations are also linked to vegetation. One study<\/a> found that areas of cities with less vegetation and higher temperatures have more lower-income residents and more Latino or black residents.
\n(Read more on the Heat Island and Equity<\/a> website.) <\/p>\n<\/div><\/li>
\nOlder trees are particularly valuable in this respect, but dead trees also play an important role. <\/p>\n<\/div><\/li>