Competition response of cloud supersaturation explains diminished Twomey effect for smoky aerosol in the tropical Atlantic

Proceedings of the National Academy of Sciences, Journal Year: 2025, Volume and Issue: 122(13)

Published: March 24, 2025

The Twomey effect brightens clouds by increasing aerosol concentrations, which activates more droplets and decreases cloud supersaturation in response to competition for water vapor. To quantify this response, we used marine low observations clean smoky conditions at Ascension Island the tropical South Atlantic during Layered Aerosol Smoke Interactions with Cloud (LASIC) campaign. These show similar increases droplet number increased accumulation-mode particles from surface-based satellite retrievals, demonstrating importance of below-cloud measurements retrieving aerosol–cloud interactions (ACI) conditions. Four methods estimating were compared, scene-based parcel-based showing sufficient variability a strong dependence on both accumulation concentration cloud-base updraft velocities. Decomposing aerosol-related changes albedo optical depth shows calculated accounts dampening activation 12 35%, explaining diminished high concentrations observed LASIC previously around world. This result was consistent independent retrievals condensation nuclei multimode size-resolving Lagrangian methods. Translating effects local radiative forcing as proxy preindustrial present-day showed that reduces cooling providing an essential process-specific constraint improving representation climate model simulation indirect forcing.

Language: Английский

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Unveiling the effects of post-monsoon agricultural biomass burning on aerosols, clouds, and radiation in Northwest India

Progress in Earth and Planetary Science, Journal Year: 2025, Volume and Issue: 12(1)

Published: Feb. 5, 2025

Language: Английский

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Impacts of Anthropogenic Emission Change Scenarios on U.S. Water and Carbon Balances at National and State Scales in a Changing Climate

Earth s Future, Journal Year: 2025, Volume and Issue: 13(4)

Published: April 1, 2025

Abstract The U.S. water supply and carbon sequestration are increasingly threatened by future climate change air pollution. This study investigates the ecohydrological responses to individual combined impacts of anthropogenic emission (referring only pollutants, excluding greenhouse gases) changes at two spatial scales coupling a regional online‐coupled meteorology chemistry model (WRF‐Chem) balance (WaSSI). Combined effects in 2046–2055 relative 2001–2010 over US enhance hydrological cycle sequestration. However, drying trend occurs central part western Climate is projected dominate most regions. Anthropogenic under conditions cools down inland resource regions with 0.01–0.15°C, moisturizes east dry west More stringent control enhances precipitation ecosystem production but has an opposite modeling California North Carolina based on 4‐km resolution meteorological data 2050 2005 shows varying magnitudes patterns compared results 36‐km data. Projected pollutant emissions may accelerate climatic warming coastal areas state New Mexico decrease precipitation, runoff, Strategies address possible problems such as heatwaves, stress, productivity should consider interplay between quality different scales.

Language: Английский

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Change in precipitation pattern over South Asia in response to the trends in regional warming and free-tropospheric aerosol loading

Scientific Reports, Journal Year: 2024, Volume and Issue: 14(1)

Published: June 24, 2024

Abstract Spatial and temporal shifts in rainfall patterns over South Asia the adjoining Seas during pre-monsoon season have been observed past 2 decades from 2000 to 2019. Aerosol particles suspended above boundary layer are a contributing factor these changes. These not only alter cloud characteristics, but also diminish lapse rate, thereby suppressing convective activity, leading precipitation anomalies. Over decades, high-rainfall regions experienced declining rainfall, while low-rainfall received increased rainfall. Coinciding with notable anomalies precipitation, contrasting trends aerosol optical depth, particularly due absorbing aerosols elevated of atmosphere, seen. Apart aerosols, several factors considered that critical modifying study region, such as water vapor content, processes, lower-level relative humidity. We potential transport excess by ambient circulation oceanic having reduced rain, Bay Bengal Arabian Sea, higher latitudes enabling anomaly at distant locations.

Language: Английский

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Validation of MODIS AOD retrievals in West Africa: a comparison with AERONET observations

Air Quality Atmosphere & Health, Journal Year: 2023, Volume and Issue: 16(10), P. 2085 - 2094

Published: July 14, 2023

Language: Английский

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Leveraging Deep Learning as a New Approach to Layer Detection and Cloud–Aerosol Classification Using ICESat-2 Atmospheric Data

Remote Sensing, Journal Year: 2024, Volume and Issue: 16(13), P. 2344 - 2344

Published: June 27, 2024

NASA’s Ice, Cloud, and land Elevation Satellite (ICESat-2), designed for surface altimetry, plays a pivotal role in providing precise ice sheet elevation measurements. While its primary focus is ICESat-2 also offers valuable atmospheric data. Current conventional processing methods producing data products encounter challenges, particularly conditions with low signal or high background noise. The thresholding technique traditionally used feature detection lidar uses threshold value to accept signals while rejecting noise, which may result loss false the presence of excessive Traditional approaches improving detection, such as averaging, lead trade-off between resolution accuracy. In addition, discrimination cloud from aerosol identified features difficult given ICESat-2’s single wavelength lack depolarization measurement capability. To address these we demonstrate cloud–aerosol using deep learning-based semantic segmentation by convolutional neural network (CNN). key findings our research are effectiveness learning model classification model’s surprising capability detect complex at finer than currently possible traditional techniques. We identify several examples where algorithms struggle, like scenarios layers vertically stacked clouds, clouds embedded within aerosol, ability CNN features, resolving boundaries adjacent detecting hidden fine resolution.

Language: Английский

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Aerosol Effects on Water Cloud Properties in Different Atmospheric Regimes

Journal of Geophysical Research Atmospheres, Journal Year: 2023, Volume and Issue: 128(24)

Published: Dec. 9, 2023

Abstract Aerosol‐cloud interaction remains one of the least understood processes in climate science arena, despite its profound impacts radiation and water budget perturbations. The aerosol effects on clouds largely depend characteristics. Here, we implemented 17‐year (2003–2020) data set aerosol, cloud, meteorological factors collected over East Asia—a highly polluted region with recent decreasing trend air pollution due to control measures—to elucidate atmospheric regime‐dependent cloud properties by simultaneously accessing response measures field. study found a very close relationship between loading modifications continental Asia significant further revealed that aerosols atmosphere affected micro‐ macro‐physics differently than clean maritime atmosphere: former, increased stability under base then enhanced droplet collision‐coalescence process, resulting increase size top height; whereas latter, decreased without notable influence thermodynamics height. This showed complex aerosol‐cloud process mixed effect atmospheres. In all regimes, fraction was loading.

Language: Английский

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Aerosol processes perturb cloud trends over Bay of Bengal: observational evidence

npj Climate and Atmospheric Science, Journal Year: 2023, Volume and Issue: 6(1)

Published: Sept. 6, 2023

Abstract Although, the aerosol-cloud interactions and its impact on daily to seasonal radiation/temperature has been well observed over South Asia in last two decade, role of cloud occurrence trends (and surface temperature) is yet not evident. Here, evidence aerosol-induced control Northern Bay Bengal (NBOB) during monsoon onset period presented. In 15 years, increased aerosol emissions North India have led an increase loading at elevated altitude 1–3 km NBOB outflow region period. This induces increases air temperature 1–2 stabilizes lower troposphere recent years. The enhanced atmospheric stability caused low-level occurrences (below 3 km) years by ~20%, potentially contributing non-intuitive cooling sea temperatures. These aerosol-cloud-climate observations emphasize crucial need for improved representations coupled ocean-atmosphere models accurate predictions climate change Asia.

Language: Английский

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Aerosol impacts on summer precipitation forecast over the North China Plain by using Thompson aerosol-aware scheme in WRF: Statistical analysis and significant threat score improvements in polluted condition during June to August 2018

Atmospheric Research, Journal Year: 2023, Volume and Issue: 299, P. 107177 - 107177

Published: Dec. 12, 2023

Language: Английский

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Research on Temperature Control Index for High Concrete Dams Based on Information Entropy and Cloud Model from the View of Spatial Field

Water, Journal Year: 2023, Volume and Issue: 15(22), P. 4023 - 4023

Published: Nov. 20, 2023

It is significant to adopt scientific temperature control criteria for high concrete dams in the construction period according practical experience and theoretical calculation. This work synthetically uses information entropy a cloud model develops novel situ observation data-based indexes from view of spatial field. The order degree disorder values are defined probability principle. Information weight parameters combined describe distribution characteristics Weight optimized via projection pursuit analysis (PPA), then field (TFE) constructed. Based on above work, multi-level set up model. Finally, case study conducted verify performance proposed method. According calculation results, change law TFEs agrees with actual situations, indicating that established TFE reasonable, application conditions wider than those typical small method, determined improve safety management level dams. Research results offer reference technical support standards adopted at other similar projects.

Language: Английский

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