Polluted megacities are warming slower due to aerosol

While global warming accelerates, highly polluted megacities like Mumbai are experiencing slower warming rates due to sunlight-reflecting aerosol particles.

Lylla Younes reports for Grist.


In short:

  • Researchers found pollution in megacities temporarily slows warming by reflecting sunlight back into space.
  • This cooling effect is short-lived and stems from harmful pollutants like aerosols.
  • As countries clean up pollution, vulnerable populations face increased heat exposure risks.

Key quote:

“The poorer you are the hotter it gets, where heat is a metaphor for all forms of climate disruption.”

— Christopher Schwalm, Risk Program Director, Woodwell Climate Research Center

Why this matters:

Polluted cities may see temporary relief from rising temperatures, but this masks the broader risks of climate change. As pollution decreases, under-resourced communities are most vulnerable to extreme heat, worsening global inequality.

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