Effects of Pollen on Hydrometeors and Precipitation in a Convective System

Journal of Geophysical Research Atmospheres, Journal Year: 2024, Volume and Issue: 129(6)

Published: March 11, 2024

Abstract Anemophilous (wind‐driven) pollen is one type of primary biological aerosol particle, which can rupture under high humidity conditions and form smaller sub‐pollen particles (SPPs). Both SPPs reach the upper troposphere convective conditions, acting as cloud condensation nuclei (CCN) ice nucleating (INPs), thus influencing formation precipitation. However, impacts these aerosols on cold local climate remain unclear there are large uncertainties their emission flux abilities. Here, we incorporate processes in Weather Research Forecasting Model with Chemistry (WRF‐Chem) simulations update Morrison microphysics scheme within WRF‐Chem using aerosol‐aware INP parameterizations to account for addition other anthropogenic biogenic aerosol. SPP derived from laboratory experiments. When including rates observed a series chamber studies, concentrations increase, leading an increase water by up 50% potentially extending duration system. Among all simulated hydrometeors, graupel raindrops exhibit largest enhancements inclusion SPPs, intensifying precipitation at backside system greater spatial extent. Sensitivity indicate that have effect microphysical than whole grains, further observational evidence needed constrain processes.

Language: Английский

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High interspecific variability in ice nucleation activity suggests pollen ice nucleators are incidental

Biogeosciences, Journal Year: 2024, Volume and Issue: 21(13), P. 3201 - 3214

Published: July 12, 2024

Abstract. Ice-nucleating macromolecules (INMs) produced by plant pollen can nucleate ice at warm temperatures and may play an important role in weather- climate-relevant cloud glaciation. INMs have also proved useful for mammalian cell tissue model cryopreservation. The high nucleation (IN) activity of some indicates underlying biological function, either freezing tolerance or bioprecipitation-mediated dispersal. Here, using the largest study to date, we show that phylogenetic proximity, spermatophyte subdivision, primary growth biome, pollination season, method, desiccation native elevation do not account IN released from different species' pollen. results suggest these are plants a purpose unrelated incidental ability ice. This been adapted species specific purposes, producing exceptional nucleators. Pollen be more active, widespread nature, diverse than previously thought.

Language: Английский

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Influence Factors on Airborne Pollen Dispersal in a Tropical Island over China: Morphology and Meteorology

Atmospheric Environment X, Journal Year: 2025, Volume and Issue: unknown, P. 100323 - 100323

Published: April 1, 2025

Language: Английский

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Environmental drivers of the allergenic load caused by Ambrosia artemisiifolia pollen and its major allergen Amb a 1 in the atmosphere

International Journal of Biometeorology, Journal Year: 2025, Volume and Issue: unknown

Published: April 29, 2025

Language: Английский

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Assessing the global contribution of marine, terrestrial bioaerosols, and desert dust to ice-nucleating particle concentrations

Published: April 19, 2024

Abstract. Aerosol-cloud interactions, and particularly ice crystals in mixed-phase clouds (MPC), stand as a key source of uncertainty climate change assessments. State-of-the-art laboratory-based parameterizations were introduced into global chemistry-transport model to investigate the contribution mineral dust, marine primary organic aerosol (MPOA), terrestrial biological particles (PBAP) nucleating (INP) MPC. INP originating from PBAP (INPPBAP) are found be at low altitudes between -10 °C -20 °C, tropics, with pronounced peak Northern Hemisphere (NH) during boreal summer. INPPBAP contributes about 27 % (in NH) 30 SH) population. Dust-derived (INPD) show prominent presence high all seasons, dominating temperatures below -25 constituting 68 average column burden. MPOA-derived (INPMPOA) dominate Southern (SH), subpolar polar latitudes for -16 representing approximately 46 population SH. When evaluated against available observational data, achieves its highest predictability across temperature ranges when both INPD INPMPOA included. The additional introduction slightly reduces skills lower than oC; however, main contributors warm-temperature nucleation events. Therefore, consideration dust bioaerosol IPN precursors is required simulate models. In this respect, emissions, ice-nucleating activity each particle type evolution atmospheric transport require further investigations.

Language: Английский

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High interspecific variability indicates pollen ice nucleators are incidental

Published: Jan. 2, 2024

Abstract. Ice nucleating molecules (INMs) produced by plant pollen can nucleate ice at warm temperatures and may play an important role in weather climate relevant cloud glaciation. INMs have also proved useful for mammalian cell tissue model cryopreservation. The high nucleation (IN) activity of some indicates underlying biological function, either freezing tolerance or bioprecipitation mediated dispersal. Here, using the largest study to date, we show that phylogenetic proximity, spermatophyte subdivision, primary growth biome, pollination season, method, desiccation native elevation do not account IN released from different species’ pollen. results suggest a polysaccharide present is plants purpose unrelated has incidental ability ice. This been adapted species specific purposes, producing exceptional nucleators. Pollen be more active, widespread nature, diverse than previously thought.

Language: Английский

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An Investigation on Potential Dispersal of Airborne Pollen Over China and Their Impact on Climate as Ice Nuclei Using RegCM‐Pollen

Journal of Geophysical Research Atmospheres, Journal Year: 2024, Volume and Issue: 129(11)

Published: June 1, 2024

Abstract Pollen can serve as an effective ice‐nuclei (IN), altering cloud microphysical and radiative properties, thus precipitation life cycles. Here, a nationwide pollen emission inventory with horizontal resolution of 5 km was established based on parameterization scheme mass balance grain fluxes surrounding the plant crowns, using satellite observational data sets (including leaf area index fractional vegetation cover) well rates. The potential is then implemented in RegCM‐pollen model which treated aerosol tracers. Besides, pollen‐IN schemes were incorporated to simulate interactions between ice clouds. Investigations show that mean annual China 2.65 × 10 7 grains m −2 yr −1 , mainly distributed south northeast China. IN magnitude determined by combination temperature concentration. Notably, increasing number concentration produces opposite effects Southern (SC) Northern (NC). weakened upward motion vertical transport water vapor NC made clouds hardly form, resulting forcing (CF) +0.86 W/m 2 . In contrast, it generates CF −0.84 SC owing expanded cover. changes shortwave more significant compared longwave two regions. At surface, net +0.74 while −0.51 SC. Among them, downward approximately twice 1.4 times NC. Surface shows rising over NC, ranging from 0.05 0.25 K. SC, primarily decreasing −0.12 −0.03 effect also causes decline (−0.17 mm/day) rise (0.09 mm/day). Our results suggest complex, yet understanding its impact radiation climate atmosphere.

Language: Английский

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Machine learning methods for low-cost pollen monitoring – Model optimisation and interpretability

The Science of The Total Environment, Journal Year: 2023, Volume and Issue: 903, P. 165853 - 165853

Published: Aug. 5, 2023

Pollen is a major issue globally, causing as much 40 % of the population to suffer from hay fever and other allergic conditions. Current techniques for monitoring pollen are either laborious slow, or expensive, thus alternative methods needed provide timely more localised information on airborne concentrations. We have demonstrated previously that low-cost Optical Particle Counter (OPC) sensors can be used estimate concentrations when machine learning process data learn relationships between OPC output conventionally measured This study demonstrates how methodical hyperparameter tuning employed significantly improve model performance. present results range models based tuned configurations trained predict Poaceae (Barnhart), Quercus (L.), Betula Pinus (L.) total The achieved here significant improvement we reported: average R2 scores at least doubled compared using previous parameter settings. Furthermore, employ explainable Artificial Intelligence (XAI) technique, SHAP, interpret understand each input features (i.e. particle sizes) affect estimated concentration type. In particular, found has strong positive correlation with particles optical diameter 1.7-2.3 μm, which distinguishes it types such may suggest type-specific subpollen in this size range. There further work done, especially training testing obtained across different environments evaluate extent generalisability. Nevertheless, potential method offer valuable insight gain what learned.

Language: Английский

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Machine Learning Methods for Low-Cost Pollen Monitoring – Model Optimisation and Interpretability

Published: Jan. 1, 2023

Pollen is a major issue globally, causing as much 40% of the population to suffer from hay fever and other allergic conditions. Current techniques for monitoring pollen are either laborious slow, or expensive, thus alternative methods needed provide timely more localised information on airborne concentrations. We have demonstrated previously that low-cost Optical Particle Counter (OPC) sensors can be used estimate concentrations when machine learning process data learn relationships between OPC output conventionally measured This study demonstrates how methodical hyperparameter tuning employed significantly improve model performance. present results range models based tuned configurations trained predict Poaceae, Quercus, Betula, Pinus total The achieved here significant improvement we reported: average R2 scores at least doubled compared using previous parameter settings.Furthermore, employ explainable Artificial Intelligence (XAI) technique, SHAP, interpret understand each input features (i.e. particle sizes) affect estimated concentration taxa. In particular, found Quercus has strong positive correlation with particles optical diameter 1.7-2.3 µm, which distinguishes it taxa such Poaceae may suggest taxa-specific subpollen in this size range. There further work done, especially training testing obtained across different environments evaluate extent generalisability. Nevertheless, potential method offer valuable insight gain what learned.

Language: Английский

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Comment on egusphere-2023-2705

Published: Jan. 30, 2024

Abstract. Ice nucleating molecules (INMs) produced by plant pollen can nucleate ice at warm temperatures and may play an important role in weather climate relevant cloud glaciation. INMs have also proved useful for mammalian cell tissue model cryopreservation. The high nucleation (IN) activity of some indicates underlying biological function, either freezing tolerance or bioprecipitation mediated dispersal. Here, using the largest study to date, we show that phylogenetic proximity, spermatophyte subdivision, primary growth biome, pollination season, method, desiccation native elevation do not account IN released from different species’ pollen. results suggest a polysaccharide present is plants purpose unrelated has incidental ability ice. This been adapted species specific purposes, producing exceptional nucleators. Pollen be more active, widespread nature, diverse than previously thought.

Language: Английский

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