Transport of pollution to a remote coastal site during gap flow from California's interior: impacts on aerosol composition, clouds, and radiative balance

Martin, Andrew; Cornwell, Gavin C.; Atwood, Samuel A.; Moore, Kathryn A.; Rothfuss, Nicholas E.; Taylor, Hans P.; DeMott, Paul J.; Kreidenweis, Sonia M.; Petters, M. D.; Prather, Kimberly A.

doi:10.5194/acp-17-1491-2017

Cited by 21 publications

(40 citation statements)

References 62 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, the reconstruction overpredicts activated fraction for the marine clusters, with the largest discrepancies at low supersaturations and low CCN number concentrations. Similar behaviors in overprediction of CCN concentrations based on reconstructions using hygroscopicity and size distributions have been noted before (McFiggans et al, 2006). Kammermann et al (2010) reviewed a number of studies that compared such predicted CCN concentrations against observed values and found biases were often largest at supersaturations below 0.3 %, where predictions deviated from observations by factors ranging from 0.6 to 3.3, with most studies finding overprediction occurred.…”

Section: Comparison Of Reconstructed and Directly Measured Ccn Spectrasupporting

confidence: 62%

“…stainless steel tube inlets routed through the roof of the mobile lab to a height of approximately 5 m above the ground, before the flow was split and sent to various instruments described further below. A map and additional description of the site and instrumentation are provided in Martin et al (2017). Local meteorological measurements were obtained from a 10 m surface met tower located approximately 100 m north of the mobile lab and operated as part of a NOAA/ESRL observation network (White et al, 2013).…”

Section: Methods and Site Descriptionmentioning

confidence: 99%

“…Aerosol size distribution measurements made during CalWater-2015 at BML are described in detail in Martin et al (2017). This study used size distribution measurements for particle diameters between 14 and 730 nm from a TSI 3080 Scanning Mobility Particle Sizer (SMPS) using a 0.3 L min −1 sample flow rate and 3.0 L min −1 sheath flow rate.…”

Section: Aerosol Size Distribution Measurements (Smps)mentioning

confidence: 99%

“…As described in Martin et al (2017), size-resolved CCN concentrations (srCCN) were measured using a DMT cloud condensation nuclei counter (CCN-100) coupled with a TSI 3080 SMPS to scan across a range of particle diameters (12-540 nm at water supersaturation of s = 0.1 %, 0.19 %, 0.28 %, 0.44 %, 0.58 %, 0.67 %). An apparent hygroscopicity parameter κ (Petters and Kreidenweis, 2007) was calculated from these scans as described in Petters and Petters (2016).…”

Section: Ccn Measurementsmentioning

confidence: 99%

“…During these diurnal shifts between various terrestrial clusters, the cluster with the larger median diameter was typically associated with the sea breeze and transport from oceanic regions, while the smaller diameter cluster was associated with the land-breeze and transport from terrestrial regions. As aging of terrestrial aerosol typically leads to an increase in the median diameter of the aerosol modes, these four clusters may therefore be indicative of various degrees of aging of regional terrestrial aerosol during "sea-breeze re- sampling" at BML (Martin et al, 2017). Resampling occurs when terrestrial and marine aerosol populations mix and flow across the coastal boundary at low levels, leading to a region of mixed aerosol populations wherein the larger number concentrations associated with terrestrial types dominate the observed number concentrations in the resulting littoral zone air mass.…”

Section: Terrestrial Population Typesmentioning

confidence: 99%

See 4 more Smart Citations

Classification of aerosol population type and cloud condensation nuclei properties in a coastal California littoral environment using an unsupervised cluster model

et al. 2019

Self Cite

View full text Add to dashboard Cite

Abstract. Aerosol particle and cloud condensation nuclei (CCN) measurements from a littoral location on the northern coast of California at Bodega Bay Marine Laboratory (BML) are presented for approximately six weeks of observations during the boreal winter–spring as part of the CalWater-2015 field campaign. The nature and variability of surface (marine boundary layer, MBL) aerosol populations were evaluated by classifying observations into periods of similar aerosol and meteorological characteristics using an unsupervised cluster model to derive distinct littoral aerosol population types and link them to source regions. Such classifications support efforts to understand the impact of changing aerosol properties on precipitation and cloud development in the region, including during important atmospheric river (AR) tropical moisture advection events. Eight aerosol population types were identified that were associated with a range of impacts from both marine and terrestrial sources. Average measured total particle number concentrations, size distributions, hygroscopicities, and activated fraction spectra between 0.08 % and 1.1 % supersaturation are given for each of the identified aerosol population types, along with meteorological observations and transport pathways during time periods associated with each type. Five terrestrially influenced aerosol population types represented different degrees of aging of the continental outflow from the coast and interior of California, and their appearance at the BML site was often linked to changes in wind direction and transport pathways. In particular, distinct aerosol populations, associated with diurnal variations in source regions induced by land- and sea-breeze shifts, were classified by the clustering technique. A terrestrial type representing fresh emissions, and/or a recent new particle formation event, occurred in approximately 10 % of the observations. Over the entire study period, three marine-influenced population types were identified that typically occurred when the regular diurnal land and sea-breeze cycle collapsed and BML was continuously ventilated by air masses from marine regions for multiple days. These marine types differed from each other primarily in the degree of cloud processing evident in the size distributions, and in the presence of an additional large-particle mode for the type associated with the highest wind speeds. One of the marine types was associated with a multi-day period during which an atmospheric river made landfall at BML. Differences between many of the terrestrial and marine population types in total CCN number concentrations active at a specific supersaturation were often not as pronounced as the associated differences in the corresponding activated fraction spectra, particularly for supersaturations below about 0.4 %. This finding was due to the generally higher number concentrations in terrestrial air masses offsetting the lower fraction of particles activating at low supersaturations. At higher supersaturations, CCN concentrations for aged terrestrial types were typically above those of the marine types due to their higher number concentrations.

show abstract

Section: Comparison Of Reconstructed and Directly Measured Ccn Spectrasupporting

confidence: 62%

Section: Methods and Site Descriptionmentioning

confidence: 99%

Section: Aerosol Size Distribution Measurements (Smps)mentioning

confidence: 99%