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Monitoring Methods

Yosemite Project

In 2003-2004, researchers at Colorado State University in cooperation with NPS staff plan to continue analyses of chemical samples and data from the Yosemite smoke study. The summer 2002 field study focused on the role of smoke in regional haze. Field measurements made in Yosemite included a suite of physical and chemical measurements. These included characterizing the complete aerosol size distribution, size-resolved chemical composition, hygroscopic growth, and optical properties. Chemical measurements included both time-integrated and semi-continuous measurements.

IMPROVE Nitrate Study

NPS and Colorado State University researchers have planned a series of field and laboratory studies for 2004 to investigate the characteristics of nitrate and other ions in aerosol particles at selected, selected IMPROVE sites. These measurements are designed to address the following issues:

  • Does extraction of IMPROVE nylon filters with deionized water provide efficient recovery of collected nitrate particles?
  • Does collection of fine particles on nylon filters produce a negative bias in ammonium concentrations, due to loss of volatilized ammonia, at IMPROVE sites?
  • What are the size distributions of nitrate, and other species, in aerosol particles present at characteristic IMPROVE sites?
  • What are the gas-particle distributions of nitric acid/nitrate and ammonia/ammonium at selected IMPROVE sites?

Smoke Aerosol Source Characterization Tests

NPS and Colorado State University researchers are currently developing plans for measuring the chemical and physical characteristics of smoke produced by controlled burns in the USFS burn chamber in Missoula, Montana. An initial set of measurements is being discussed for the 2003-04 timeframe, to include measurement of aerosol size distributions, hygroscopicity, and chemical composition (if scheduling permits). Sampling will be conducted using CSU's dilution tunnel sampler. These initial measurements are expected to form the basis for additional measurements in the future that will provide critical information about the physical and chemical properties of smoke aerosol produced during various burn phases in the combustion of different fuel types.

updated on 12/08/2005  I   http://nature.nps.gov/air/Studies/vis_methodstudy.cfm   I  Email: Webmaster