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Abstract We introduce and study a one parameter deformation of the polynuclear growth (PNG) in (1+1)-dimensions, which we call the $$t$$-PNG model. It is defined by requiring that, when two expanding islands merge, with probability $$t$$ they sprout another island on top of the merging location. At $t=0$, this becomes the standard (non-deformed) PNG model that, in the droplet geometry, can be reformulated through longest increasing subsequences of uniformly random permutations or through an algorithm known as patience sorting. In terms of the latter, the $$t$$-PNG model allows errors to occur in the sorting algorithm with probability $$t$$. We prove that the $$t$$-PNG model exhibits one-point Tracy–Widom Gaussian Unitary Ensemble asymptotics at large times for any fixed $$t\in [0,1)$$, and one-point convergence to the narrow wedge solution of the Kardar–Parisi–Zhang equation as $$t$$ tends to $$1$$. We further construct distributions for an external source that are likely to induce Baik–Ben Arous–Péché-type phase transitions. The proofs are based on solvable stochastic vertex models and their connection to the determinantal point processes arising from Schur measures on partitions. 

This dataset includes aerosol microphysics and chemical measurements collected at Mt. Soledad and Scripps Pier during the Eastern Pacific Cloud Aerosol Precipitation Experiment (EPCAPE) from February 2023 to February 2024. The measurements include the following instruments at Mt. Soledad: High-Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS, Aerodyne), Scanning Electrical Mobility Spectrometer (SEMS, Brechtel Manufacturing Inc.), Aerodynamic Particle Sizer (APS, Droplet Measurements Technologies), Single Particle Soot Photometer (SP2, Drople Measurements Technologies), Meteorological Station (WXT520, Vaisala), Ozone (Teco), and trace gas proxies (Teledyne). In addition, the analyses of particle filters collected at Mt. Soledad for three dry-diameter size cuts (<1 micron, <0.5 micron, <0.18 micron) and at Scripps Pier for one dry-diametr size cut (<1 micron) by Fourier Transform Infrared (FTIR) and X-ray Fluorescence (XRF) are reported. A differential mobility analyzer operated as a scanning mobility particle sizer (SMPS, TSI Inc.), a printed particle optical spectrometer (POPS, Grimm), and a continuous flow diffusion cloud condensation nuclei (CCN, DMT) counter provide the mobility aerosol size distribution (30-360 nm), optical size distribution (150 - 6000 nm), size-resolved CCN distribution (30-360 nm) at 0.2, 0.4, 0.6, 0.8, and 1.0% supersaturation. Measurements are reported for both sampling from an isokinetic aerosol inlet and from a Counterflow Virtual Impactor (CVI, Brechtel Manufacturing Inc.). Users of these measurements are encouraged to consult with the authors about appropriate interpretation before submitting for publication, offering coauthorship where appropriate. 

Wildfire impacts on air quality and climate are expected to be exacerbatedby climate change with the most pronounced impacts in the boreal biome.Despite the large geographic coverage, there is limited information onboreal forest wildfire emissions, particularly for organic compounds, whichare critical inputs for air quality model predictions of downwind impacts.In this study, airborne measurements of 193 compounds from 15 instruments,including 173 non-methane organics compounds (NMOG), were used to providethe most detailed characterization, to date, of boreal forest wildfireemissions. Highly speciated measurements showed a large diversity ofchemical classes highlighting the complexity of emissions. Usingmeasurements of the total NMOG carbon (NMOGT), the ΣNMOG wasfound to be 50 % ± 3 % to 53 % ± 3 % of NMOGT, of which, theintermediate- and semi-volatile organic compounds (I/SVOCs) were estimatedto account for 7 % to 10 %. These estimates of I/SVOC emission factorsexpand the volatility range of NMOG typically reported. Despite extensivespeciation, a substantial portion of NMOGT remained unidentified(47 % ± 15 % to 50 % ± 15 %), with expected contributions from morehighly-functionalized VOCs and I/SVOCs. The emission factors derived in thisstudy improve wildfire chemical speciation profiles and are especiallyrelevant for air quality modelling of boreal forest wildfires. Theseaircraft-derived emission estimates were further linked with those derivedfrom satellite observations demonstrating their combined value in assessingvariability in modelled emissions. These results contribute to theverification and improvement of models that are essential for reliablepredictions of near-source and downwind pollution resulting from borealforest wildfires. 

Abstract. Forest fires are major contributors of reactive gas- and particle-phaseorganic compounds to the atmosphere. We used offline high-resolution tandemmass spectrometry to perform a molecular-level speciation of gas- andparticle-phase compounds sampled via aircraft from an evolving boreal forestfire smoke plume in Saskatchewan, Canada. We observed diversemultifunctional compounds containing oxygen, nitrogen, and sulfur (CHONS),whose structures, formation, and impacts are understudied. Thedilution-corrected absolute ion abundance of particle-phase CHONS compoundsincreased with plume age by a factor of 6.4 over the first 4 h ofdownwind transport, and their relative contribution to the observedfunctionalized organic aerosol (OA) mixture increased from 19 % to 40 %.The dilution-corrected absolute ion abundance of particle-phase compoundswith sulfide functional groups increased by a factor of 13 with plume age,and their relative contribution to observed OA increased from 4 % to40 %. Sulfides were present in up to 75 % of CHONS compounds and theincreases in sulfides were accompanied by increases in ring-bound nitrogen;both increased together with CHONS prevalence. A complex mixture ofintermediate- and semi-volatile gas-phase organic sulfur species wasobserved in emissions from the fire and depleted downwind, representingpotential precursors to particle-phase CHONS compounds. These resultsdemonstrate CHONS formation from nitrogen- and oxygen-containing biomass burningemissions in the presence of reduced sulfur species. In addition, theyhighlight chemical pathways that may also be relevant in situations withelevated emissions of nitrogen- and sulfur-containing organic compounds fromresidential biomass burning and fossil fuel use (e.g., coal), respectively.