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The cities of Khartoum and Omdurman in Sudan


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      As any urban dweller who has lived through a heat wave knows, a shady tree can make all the difference. But what happens when there’s no shade available?
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      Researchers found that cities in the Global South have just 70% of the greenery-related cooling capacity of cities in the Global North. The green spaces in an average Global South city cool the temperature by about 4.5 F (2.5 C). In an average Global North city, that cooling capacity is 6.5 F (3.6 C). This compounds an existing problem: cities in the South tend to be at lower latitudes (that is, nearer to the Equator), which are predicted to see more heat extremes in the coming years.
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      Mogadishu is a dense city with a dry climate that limits vegetation growth. Still, there’s a lot that each city can learn from its neighbors. Within a given region, the researchers identified the city with the greatest cooling capacity and used that as a goal. They calculated the difference between the best-performing city in the region and every city nearby to get the potential additional cooling capacity. They found that cities’ average cooling capacity could be increased substantially — to as much as 18 F (10 C) — by systematically increasing green space quantity and quality.
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      With a global study like this, urban planners can compare strategies for cities within the same region or with similar densities. “For newly urbanized areas that aren’t completely built out, there’s a lot of room to still change the design,” Braneon said.
      By Madeleine Gregory
      NASA’s Goddard Space Flight Center, Greenbelt, Md.
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      Details
      Last Updated Nov 26, 2024 Editor Rob Garner Contact Rob Garner rob.garner@nasa.gov Location Goddard Space Flight Center Related Terms
      Climate Change Earth Goddard Institute for Space Studies Goddard Space Flight Center Landsat Landsat 8 / LDCM (Landsat Data Continuity Mission) View the full article
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