Ground PM2.5 and Upper Air



Ho Chi Minh City

Ho Chi Minh


Top graph

  • black line: a theoretical parcel (of air) lapse-rate temperature
  • green line: dewpoint temperature
  • red line: observed temperature of parcel (of air)
  • Temperature inversion occurs when a layer of hotter air sits on top the ground layer indicated as patch in blue in SkewT graph (near the ground). The favorable condition for the vertial mixing is the temperature of the air reduces as the high increased (the ground is the lowest point).

    Bottom-right graph

    Hodograph: showing the wind speed and direction (in knots (1.85km/h) and direction (in degree) with the color bar in meters)

    Botom-left graph

    Observed concentration of fine particulate matter (PM2.5) by a FEM station operated by US Embassy in Hanoi or US Consulate in Ho Chi Minh City


  • A longer (and more comprehensive) post on about temperature inversion
  • SkewT explaination (with lots of graph) from
  • A condensed post about SkewT (more technical)
  • So many text, I want a video, and here you are . This video will walk you through air pollution. Temperature inversion starts around 5:00.