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    <identifier>10.57760/sciencedb.20703</identifier>
    <datestamp>2025-02-10T10:07:57Z</datestamp>
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<oai_dc:dc xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
  <dc:date>2025-02-10</dc:date>
  <dc:title>The number of good air quality days in 367 Chinese cities (2014&amp;ndash;2024)</dc:title>
  <dc:identifier>doi:10.57760/sciencedb.20703</dc:identifier>
  <dc:language>en</dc:language>
  <dc:description>According to China&amp;rsquo;s Air Quality Standard (GB 3095-2012), an Air Quality Index (AQI) of &amp;le;50 is classified as excellent, &amp;le;100 as good, &amp;le;150 as light pollution, &amp;le;200 as moderate pollution, &amp;le;300 as heavy pollution, and &amp;gt;300 as severe pollution. Using daily data from the China National Environmental Monitoring Center, we have compiled a dataset tracking the annual number of good air quality days (i.e., days with AQI &amp;le;100) across 367 cities in China from 2014 to 2024. This dataset serves as a valuable resource for assessing and analyzing urban environmental quality.</dc:description>
  <dc:subject>AQI; Air quality; Air pollution; PM2.5; number of good air quality days</dc:subject>
  <dc:creator>Liu Haimeng</dc:creator>
  <dc:rights>PUBLIC</dc:rights>
  <dc:rights>https://creativecommons.org/licenses/by-sa/4.0/</dc:rights>
  <dc:type>dataset</dc:type>
  <dc:publisher>Science Data Bank</dc:publisher>
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