Variations in Mass of the PM(subscript 10), PM(subscript 2.5) and PM(subscript 1) during the Monsoon and the Winter at New Delhi

S. Tiwari；D. M. Chate；P. Pragya；Kaushar Ali；Deewan Singh Bisht

Particulate matters ； Visibility ； Washout pattern ； Time-series variations ； Mean mass scavenging coefficient

Aerosol and Air Quality Research

12卷1期（2012 / 02 / 01）

20 - 29

英文

PM(subscript 10), PM(subscript 2.5) and PM(subscript 1) mass concentrations have been measured at Delhi (28°35'N; 77°12'E) during the August to December 2007. The running mean of PM(subscript 10), PM(subscript 2.5) and PM(subscript 1) data shows large variations. The PM(subscript 10), PM(subscript 2.5) and PM(subscript 1) were ranged from 20 to 180 μg/m^3 during the monsoon and from 100 to 500 μg/m^3 during the winter (up to 1200 μg/m^3 in November due to Deepavali fireworks). For the same running mean cycles, higher mass concentrations in the PM(subscript 10), PM(subscript 2.5) and PM(subscript 1) were corresponded with peaks in the relative humidity and lower levels linked to peaks in the ambient temperature. The evolutions of PM(subscript 10), PM(subscript 2.5) and PM(subscript 1) concentrations after the elapsed times are simulated with mean mass scavenging coefficients. These evolution patterns clearly show the difference in washout of PM(subscript 10) with impaction scavenging relative to those for PM(subscript 2.5) and PM(subscript 1) particles over different rainfall durations. Air-mass pathways traced with HYSPLIT model over the study area illustrates the nature of PM(subscript 10), PM(subscript 2.5) and PM(subscript 1) levels with monsoon and winter air-mass circulations over Delhi.