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.