Investigating processes influencing simulation of local Arctic wintertime anthropogenic pollution in Fairbanks, Alaska, during ALPACA-2022

Atmospheric chemistry and physics, Год журнала: 2025, Номер 25(2), С. 1063 - 1104

Опубликована: Янв. 28, 2025

Abstract. Lagrangian tracer simulations are deployed to investigate processes influencing vertical and horizontal dispersion of anthropogenic pollution in Fairbanks, Alaska, during the Alaskan Layered Pollution Chemical Analysis (ALPACA) 2022 field campaign. Simulated concentrations carbon monoxide (CO), sulfur dioxide (SO2), nitrogen oxides (NOx), including surface elevated sources, highest at under very cold stable conditions. enhancements above (50–300 m) mainly attributed power plant emissions. Both sources contribute Fairbanks' regional that is transported downwind, primarily south-west, may wintertime Arctic haze. Inclusion a novel plume rise treatment considers presence temperature inversion layers leads improved agreement with observed CO NOx plumes, discrepancies to, for example, displacement plumes by modelled winds. At surface, model results show variability largely driven meteorology and, lesser extent, emissions, although simulated tracers sensitive dispersion. Modelled underestimation polluted conditions considerably following inclusion substantial increases diesel vehicle emissions temperatures (e.g. factor 6 −30 °C). In contrast, overestimation SO2 deficiencies (5–18 space heating This study highlights need improvements local simulation boundary layers.

Язык: Английский

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A central arctic extreme aerosol event triggered by a warm air-mass intrusion

Nature Communications, Год журнала: 2022, Номер 13(1)

Опубликована: Сен. 8, 2022

Abstract Frequency and intensity of warm moist air-mass intrusions into the Arctic have increased over past decades been related to sea ice melt. During our year-long expedition in remote central Ocean, a record-breaking increase temperature, moisture downwelling-longwave radiation was observed mid-April 2020, during an intrusion carrying air pollutants from northern Eurasia. The two-day intrusion, caused drastic changes aerosol size distribution, chemical composition particle hygroscopicity. Here we show how transformed low-particle environment area comparable central-European urban setting. Additionally, resulted explosive cloud condensation nuclei, which can direct effects on clouds’ radiation, their precipitation patterns, lifetime. Thus, unless prompt actions significantly reduce emissions source regions are taken, such events expected continue affect climate.

Язык: Английский

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Arctic warming by abundant fine sea salt aerosols from blowing snow

Nature Geoscience, Год журнала: 2023, Номер 16(9), С. 768 - 774

Опубликована: Сен. 1, 2023

Abstract The Arctic warms nearly four times faster than the global average, and aerosols play an increasingly important role in climate change. In Arctic, sea salt is a major aerosol component terms of mass concentration during winter spring. However, mechanisms production remain unclear. Sea are typically thought to be relatively large size but low number concentration, implying that their influence on cloud condensation nuclei population properties generally minor. Here we present observational evidence abundant from blowing snow central Arctic. Blowing was observed more 20% time November April. sublimation generates high concentrations fine-mode (diameter below 300 nm), enhancing up tenfold above background levels. Using chemical transport model, estimate April north 70° N, produced accounts for about 27.6% total particle number, increases longwave emissivity clouds, leading calculated surface warming +2.30 W m −2 under cloudy sky conditions.

Язык: Английский

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A full year of aerosol size distribution data from the central Arctic under an extreme positive Arctic Oscillation: insights from the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition

Atmospheric chemistry and physics, Год журнала: 2023, Номер 23(1), С. 389 - 415

Опубликована: Янв. 11, 2023

Abstract. The Arctic environment is rapidly changing due to accelerated warming in the region. trend driving a decline sea ice extent, which thereby enhances feedback loops surface energy budget Arctic. aerosols play an important role radiative balance and hence climate response region, yet direct observations of over Ocean are limited. In this study, we investigate annual cycle aerosol particle number size distribution (PNSD), concentration (PNC), black carbon (BC) mass central during Multidisciplinary drifting Observatory for Study Climate (MOSAiC) expedition. This first continuous, year-long data set PNSD ever collected Ocean. We use k-means cluster analysis, FLEXPART simulations, inverse modeling evaluate seasonal patterns influence different source regions on population. Furthermore, compare land-based sites across Arctic, using both long-term measurements year MOSAiC expedition (2019–2020), interannual variability give context characteristics from within Our analysis identifies that, overall, exhibits typical aerosols, including anthropogenic haze winter secondary processes summer. pattern corresponds global radiation, air temperature, timing melting/freezing, drive changes transport processes. winter, Norilsk region Russia/Siberia was dominant signals BC observations, contributed higher accumulation-mode PNC concentrations than at observatories. also show that wintertime Oscillation (AO) phenomenon, reported achieve record-breaking positive phase January–March 2020, explains unusual magnitude compared longer-term observations. summer, PNCs nucleation Aitken modes enhanced; however, were notably lower pack further south. presented herein provides current snapshot characterized by rapid changes, will be crucial improving model predictions, understanding linkages between environmental processes, investigating impacts change future studies.

Язык: Английский

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Observations of high-time-resolution and size-resolved aerosol chemical composition and microphysics in the central Arctic: implications for climate-relevant particle properties

Atmospheric chemistry and physics, Год журнала: 2025, Номер 25(4), С. 2207 - 2241

Опубликована: Фев. 19, 2025

Abstract. Aerosols play a critical role in the Arctic's radiative balance, influencing solar radiation and cloud formation. Limited observations central Arctic leave gaps understanding aerosol dynamics year-round, affecting model predictions of climate-relevant properties. Here, we present first annual high-time-resolution submicron chemical composition during Ocean 2018 (AO2018) 2019–2020 Multidisciplinary drifting Observatory for Study Climate (MOSAiC) expeditions. Seasonal variations mass concentrations were found to be driven by typical seasonal regimes resemble those pan-Arctic land-based stations. Organic aerosols dominated pristine summer, while anthropogenic sulfate prevailed autumn spring under haze conditions. Ammonium, which impacts acidity, was consistently less abundant, relative sulfate, compared lower latitudes Arctic. Cyclonic (storm) activity have significant influence on variability enhancing emissions from local sources transport remote aerosol. Local wind-generated particles contributed up 80 % (20 %) condensation nuclei population (spring). While analysis presented herein provides current baseline, will serve improve climate region, it also underscores importance integrating short-timescale processes, such as wind-driven blowing snow open leads/ocean simulations. This is particularly important, given decline mid-latitude increase ones.

Язык: Английский

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Arctic spring and summertime aerosol optical depth baseline from long-term observations and model reanalyses – Part 1: Climatology and trend

Atmospheric chemistry and physics, Год журнала: 2022, Номер 22(15), С. 9915 - 9947

Опубликована: Авг. 3, 2022

Abstract. We present an Arctic aerosol optical depth (AOD) climatology and trend analysis for 2003–2019 spring summertime periods derived from a combination of multi-agency reanalyses, remote-sensing retrievals, ground observations. This includes the U.S. Navy Aerosol Analysis Prediction System ReAnalysis version 1 (NAAPS-RA v1), NASA Modern-Era Retrospective Research Applications, 2 (MERRA-2), Copernicus Atmosphere Monitoring Service (CAMSRA). Spaceborne retrievals AOD are considered Moderate Resolution Imaging Spectroradiometer (MODIS), Multi-angle SpectroRadiometer (MISR), Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP). Ground-based data include sun photometer AErosol RObotic NETwork (AERONET) sites oceanic Maritime Network (MAN) measurements. reanalysis AODs spaceborne show consistent climatological spatial patterns trends both summer seasons over lower (60–70∘ N). Consistent also found high (north 70∘ N) reanalyses. The reanalyses yield more results than climate models, can be verified well AERONET, corroborate complementary analysis. Speciated variable total among three little so March–May (MAM) June–August (JJA). Black carbon (BC) in comes predominantly biomass burning (BB) sources MAM JJA, BB overwhelms anthropogenic JJA study period. exhibits multi-year negative positive during 2003–2019, due to overall decrease sulfate/anthropogenic pollution significant increase smoke. Interannual variability is significantly large, driven by fine-mode and, specifically, smoke, smoke contribution interannual variation larger MAM. It recommended that models should account emissions variabilities change studies.

Язык: Английский

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Wildfire aerosol deposition likely amplified a summertime Arctic phytoplankton bloom

Communications Earth & Environment, Год журнала: 2022, Номер 3(1)

Опубликована: Сен. 19, 2022

Abstract Summertime wildfire activity is increasing in boreal forest and tundra ecosystems the Northern Hemisphere. However, impact of long range transport deposition aerosols on biogeochemical cycles Arctic Ocean unknown. Here, we use satellite-based ocean color data, atmospheric modeling back trajectory analysis to investigate fate emitted from Siberian wildfires summer 2014 their potential phytoplankton dynamics Ocean. We detect large blooms near North Pole (up 82°N eastern Eurasian Basin). Our indicates that these were induced by northward plume nutrient-bearing aerosols. estimate highly stratified surface waters received amounts wildfire-derived nitrogen, which alleviated nutrient stress community triggered an unusually bloom event. findings suggest changes may strongly influence summertime productivity

Язык: Английский

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Model evaluation of short-lived climate forcers for the Arctic Monitoring and Assessment Programme: a multi-species, multi-model study

Atmospheric chemistry and physics, Год журнала: 2022, Номер 22(9), С. 5775 - 5828

Опубликована: Май 4, 2022

Abstract. While carbon dioxide is the main cause for global warming, modeling short-lived climate forcers (SLCFs) such as methane, ozone, and particles in Arctic allows us to simulate near-term health impacts a sensitive, pristine region that warming at 3 times rate. Atmospheric critical understanding long-range transport of pollutants Arctic, well abundance distribution SLCFs throughout atmosphere. Modeling also used tool determine SLCF on present future emissions scenarios. In this study, we evaluate 18 state-of-the-art atmospheric Earth system models by assessing their representation Northern Hemisphere distributions, considering wide range different chemical species (methane, tropospheric ozone its precursors, black carbon, sulfate, organic aerosol, particulate matter) multiple observational datasets. Model simulations over 4 years (2008–2009 2014–2015) conducted 2022 Monitoring Assessment Programme (AMAP) assessment report are thoroughly evaluated against satellite, ground, ship, aircraft-based observations. The annual means, seasonal cycles, 3-D distributions were using several metrics, absolute percent model biases correlation coefficients. results show large performance, with no one particular or type performing all regions species. multi-model mean (mmm) was able represent general features had best overall performance. For greatest radiative impact (CH4, O3, BC, SO42-), mmm within ±25 % measurements across Hemisphere. Therefore, recommend ensemble be simulating SLCFs. Of our smallest CH4 OA. most SLCFs, skewed from positive negative increasing latitude. Our analysis suggests vertical mixing, transport, deposition, wildfires remain highly uncertain processes. These processes need better improve simulation environment. As development proceeds these areas, evaluated, information improving models.

Язык: Английский

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Increased aerosol concentrations in the High Arctic attributable to changing atmospheric transport patterns

npj Climate and Atmospheric Science, Год журнала: 2022, Номер 5(1)

Опубликована: Авг. 1, 2022

Abstract The Arctic environment has changed profoundly in recent decades. Aerosol particles are involved numerous feedback mechanisms the Arctic, e.g., aerosol-cloud/radiation interactions, which have important climatic implications. To understand changes different aerosol types and number concentrations, we performed a trend analysis of particle size distributions, their properties, associated air mass history at Villum Research Station, northeastern Greenland, from 2010 to 2018. We found that, during spring, total/ultrafine mode concentration time masses spent over open ocean is significantly increasing, can be ascribed transport patterns changing more frequent arrival ice-free Greenland Sea. summer, concentration, occurrence Nucleation cluster (i.e. newly formed gas conversion), increasing. This also attributed patterns, here with arriving frequently Baffin Bay. Finally, autumn, ultrafine Pristine clean, natural background conditions) likely due increasing amounts accumulated precipitation along trajectory path decreasing above mixed layer, respectively. Our results demonstrate that circulation factors predominantly affecting trends concentrations Greenland.

Язык: Английский

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Ice-nucleating particles in northern Greenland: annual cycles, biological contribution and parameterizations

Atmospheric chemistry and physics, Год журнала: 2023, Номер 23(8), С. 4741 - 4761

Опубликована: Апрель 20, 2023

Abstract. Ice-nucleating particles (INPs) can initiate ice formation in clouds at temperatures above −38 ∘C through heterogeneous nucleation. As a result, INPs affect cloud microphysical and radiative properties, lifetime, precipitation behavior thereby ultimately the Earth's climate. Yet, little is known regarding sources, abundance properties of INPs, especially remote regions such as Arctic. In this study, 2-year-long INP measurements (from July 2018 to September 2020) Villum Research Station northern Greenland are presented. A low-volume filter sampler was deployed collect samples for offline analysis. An annual cycle concentration (NINP) observed, fraction heat-labile found be higher months with low no snow cover lower when surface well covered (> 0.8 m). Samples were categorized into three different types based only on slope their spectra, namely summer, winter mix type. For each temperature-dependent parameterization derived, clearly depending time year. Winter summer occurred during respective seasons seen 60 % time. The mixed type remaining 40 throughout April, May November transition months. case study comparing April 2019 2020 performed. month selected because significant difference NINP observed these two periods, 2020. parallel differences NINP, also cloud-ice satellite data 2020, compared 2019. period revealed clear dependency either meteorological parameters or which passed by collected air masses. Overall, results suggest that coastal main sources most likely including both local terrestrial marine sources.

Язык: Английский

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