Oct 9, 2019

Green rooftops surge in popularity and offer environmental benefits

Photo: Xavier TESTELIN/Gamma-Rapho via Getty Images

Green rooftops are growing in popularity, offering a slew of environmental benefits, the New York Times reports.

The big picture: The rooftops on apartments or commercial buildings often feature lawn areas, grills and seating. Some host community gardens, blossoming vegetables and herbs. But the greenery, and corresponding absence of asphalt and shingles, doesn't just up the aesthetic, it lowers surrounding temperatures, reduces energy use and assists in filtering storm water.

  • Green Roofs for Healthy Cities estimates the rooftops in North America have increased roughly 15% since 2013.
  • The National Research Council of Canada estimated the rooftops can lower a building's air conditioning use up to 75%.
  • Plants on rooftops are able to absorb rain water before it hits the ground, acting as filters and reducing runoff.
  • And, through evapotranspiration, plants cool the surrounding air by evaporating moisture, allowing temperatures to cool.

Between the lines: In many cities, the rooftops are no longer optional.

  • Both New York City and San Francisco have passed requirements for newly constructed buildings to have some component of green roofs, solar panels or both.
  • In 2010, Copenhagen made green roofs a requirement for all new commercial buildings, with a caveat for those with over a 30-degree slope.
  • In 2016, Córdoba, Argentina, passed legislation requiring all rooftops over 1,300 square feet, regardless of age, to turn green.

Go deeper: How I am trying to get greener and cheaper electricity

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U.S. green economy generates $1.3 trillion and sustains 9.5 million full-time jobs

Wind turbines in Texas. Photo: Paul Harris/Getty Images

The U.S. green economy generates $1.3 trillion in annual sales revenue and sustains 9.5 million full-time jobs, according to a study from University College London published on Tuesday.

Why it matters: These numbers make it possible to compare the green sector to the traditional fossil fuel related industry and determine its impact on the economy.

Go deeperArrowOct 16, 2019

Green and sustainability debt is growing fast

Reproduced from Institute of International Finance; Chart: Axios Visuals

Green financial instruments continue to see widespread adoption and diversification, in terms of both instruments and geographies.

What's happening: Total green and sustainability debt issuance in 2019 is poised to double levels from 2017 and will be almost four times the level issued as recently as 2016, according to projections from the Institute of International Finance.

Go deeperArrowOct 24, 2019

The water crisis cities don't see coming

Illustration: Sarah Grillo/Axios

Aging water treatment systems, failing pipes and a slew of unregulated contaminants threaten to undermine water quality in U.S. cities of all sizes.

Why it matters: There's arguably nothing more important to human survival than access to clean drinking water.

Go deeperArrowOct 16, 2019