A244-03
A spatially dense aerosol instrument network in the southern great plains: POPSnet-SGP
Wednesday, 16 December 2020: 17:38
Virtual
Elizabeth Asher, Cooperative Institute for Research in Environmental Sciences, Chemical Sciences Division, Boulder, CO, United States, Troy D Thornberry, NOAA Earth System Research Laboratory, Chemical Sciences Division, Boulder, CO, United States, David W Fahey, NOAA ESRL, Boulder, CO, United States, Allison C McComiskey, Brookhaven National Laboratory, Upton, NY, United States, Kai-Lan Chang, NOAA Boulder, Boulder, CO, United States, Ken S Carslaw, University of Leeds, Leeds, United Kingdom, Lea-Sophie Grunau, University of Leeds, School of Earth and Environment, Leeds, United Kingdom and Ru-Shan Gao, NOAA Earth System Research Laboratory, Chemical Sciences Laboratory, Boulder, CO, United States
Abstract:
The sparseness of aerosol microphysical measurements has limited our understanding of global aerosol emissions, transport, and radiative effects. The Portable Optical Particle Spectrometer network – Southern Great Plains (POPSnet-SGP) project deployed a spatially dense, ground-based network of in situ aerosol measurements at 7 sites across a 150 km x 150 km region of relatively homogenous terrain at the Department of Energy Aerosol Radiation Measurement (ARM) Southern Great Plains (SGP) facility in Oklahoma in October, 2019. The project’s POPS instruments report 1 Hz measurements of aerosol number and size distribution from 130 nm – 2.5 mm (assuming a modal refractive index of n = 0.53 + 0i) and records single particle counts and sizes.
The POPSnet-SGP near-surface, ambient measurements of particle number and size at multiple locations across a relatively homogeneous, continental background region allow an assessment of the statistical representativeness of a single surface measurement under conditions where only small differences would be expected. Using data from the first year of operation, we investigate the natural variability in boundary layer aerosol volume concentrations and size distributions across the POPSnet-SGP sites. We also examine the measurement uncertainty at individual sites, assessed using pairs of POPS instruments at each site, when possible. We generally observe high coherence between aerosol volume concentrations and aerosol size distributions at each site, however periods of significant short-term variability between individual sites and the network mean value occur, often influenced by differences in local meteorology. The POPSnet mean aerosol volume is more strongly correlated with the Aerosol Robotic Network (AERONET) aerosol optical depth measured at the SGP Central Facility than measurements at any individual site, including the those at the Central Facility.
