Atmospheric new particle formation from the CERN CLOUD experiment

Nature Geoscience, Journal Year: 2023, Volume and Issue: 16(11), P. 948 - 957

Published: Nov. 1, 2023

Language: Английский

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Isoprene nitrates drive new particle formation in Amazon’s upper troposphere

Nature, Journal Year: 2024, Volume and Issue: 636(8041), P. 124 - 130

Published: Dec. 4, 2024

Abstract New particle formation (NPF) in the tropical upper troposphere is a globally important source of atmospheric aerosols 1–4 . It known to occur over Amazon basin, but nucleation mechanism and chemical precursors have yet be identified 2 Here we present comprehensive situ aircraft measurements showing that extremely low-volatile oxidation products isoprene, particularly certain organonitrates, drive NPF Amazonian troposphere. The organonitrates originate from OH-initiated isoprene forest emissions presence nitrogen oxides lightning. Nucleation bursts start about h after sunrise outflow nocturnal deep convection, producing high aerosol concentrations more than 50,000 particles cm − 3 We report characteristic diurnal cycles precursor gases particles. Our observations show interplay between biogenic convection with associated lightning, photochemistry low ambient temperature uniquely promotes NPF. grow time, undergo long-range transport descend through subsidence lower troposphere, which they can serve as cloud condensation nuclei (CCN) influence Earth’s hydrological cycle, radiation budget climate 1,4–8

Language: Английский

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New particle formation from isoprene under upper-tropospheric conditions

Nature, Journal Year: 2024, Volume and Issue: 636(8041), P. 115 - 123

Published: Dec. 4, 2024

Language: Английский

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Profiling of formaldehyde, glyoxal, methylglyoxal, and CO over the Amazon: normalized excess mixing ratios and related emission factors in biomass burning plumes

Atmospheric chemistry and physics, Journal Year: 2020, Volume and Issue: 20(20), P. 12363 - 12389

Published: Oct. 29, 2020

Abstract. We report on airborne measurements of tropospheric mixing ratios and vertical profiles formaldehyde (CH2O), glyoxal (C2H2O2), methylglyoxal higher carbonyls (C3H4O2*) (see below), carbon monoxide (CO) over the Amazon Basin during ACRIDICON-CHUVA campaign from German High Altitude Long-range research aircraft (HALO) in autumn 2014. The joint observation situ CO remotely measured CH2O, C2H2O2, C3H4O2*, together with visible imagery air mass back-trajectory modelling using NOAA HYSPLIT (National Oceanic Atmospheric Administration, HYbrid Single-Particle Lagrangian Integrated Trajectory), allows us to discriminate between probing background tropical air, which concentration species results oxidation biogenically emitted volatile organic compounds (VOCs, mostly isoprene), moderately strongly polluted masses affected by biomass burning emissions or city plume Manaus. For 12 near-surface fresh plumes, normalized excess C2H2O2 C3H4O2* respect CH2O are inferred compared recent studies. mean glyoxal-to-formaldehyde ratio RGF=0.07 (range 0.02–0.11) is good agreement reports suggest RGF be significantly lower than previously assumed global chemical transport models (CTMs). methylglyoxal-to-formaldehyde RMF=0.98 0.09–1.50) varies different observational settings but overall appears much larger (up a factor 5) previous even when applying correction 2.0±0.5 account for additional dicarbonyls included measurements. Using recently reported emission factors forests, our observations EFG=0.25 0.11 0.52) g kg−1 EFM = 4.7 0.5 8.64) C3H4O2*. While EFG agrees well reports, (like RMF) slightly other studies, presumably due ages fuels studied. Our these critical intermediate products may support future photochemical pollution vegetation, as validate past present space-borne respective species.

Language: Английский

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Measurement report: Long-range transport patterns into the tropical northwest Pacific during the CAMP<sup>2</sup>Ex aircraft campaign: chemical composition, size distributions, and the impact of convection

Atmospheric chemistry and physics, Journal Year: 2021, Volume and Issue: 21(5), P. 3777 - 3802

Published: March 15, 2021

Abstract. The tropical Northwest Pacific (TNWP) is a receptor for pollution sources throughout Asia and highly susceptible to climate change, making it imperative understand long-range transport in this complex aerosol-meteorological environment. Measurements from the NASA Cloud, Aerosol, Monsoon Processes Philippines Experiment (CAMP2Ex; 24 August 5 October 2019) back trajectories National Oceanic Atmospheric Administration Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT) were used examine into TNWP Maritime Continent (MC), peninsular Southeast (PSEA), East (EA), West (WP). A mid-campaign monsoon shift on 20 September 2019 led distinct patterns between southwest (SWM; before September) transition (MT; after September). During SWM, was function of southwesterly winds cyclones over South China Sea. Low- (high-) altitude air generally came MC implying aerosol processing related convection perhaps wind shear. MT saw EA WP, driven by northeasterly winds, continental anticyclones, Composition transported differed emission source accumulated precipitation along (APT). characterized biomass burning tracers while major components pointed Asian outflow secondary formation. Convective scavenging PSEA evidenced considerable vertical differences species but not trace gases, as well notably higher APT smaller particles than other regions. Finally, we observed possible wet mechanism acting aloft that strictly linked precipitation. These results are important understanding masses with further implications modeling lifecycles guiding international policymaking public health climate, particularly during SWM MT.

Language: Английский

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