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1. Impact of aerosols on ice crystal size

   https://doi.org/10.5194/acp-18-1065-2018  

   Zhao, Bin; Liou, Kuo-Nan; Gu, Yu; Jiang, Jonathan H.; Li, Qinbin; Fu, Rong; Huang, Lei; Liu, Xiaohong; Shi, Xiangjun; Su, Hui; et al (January 2018, Atmospheric Chemistry and Physics)

   Abstract. The interactions between aerosols and ice clouds represent one of the largest uncertainties in global radiative forcing from pre-industrial time to the present. In particular, the impact of aerosols on ice crystal effective radius (R_ei), which is a key parameter determining ice clouds' net radiative effect, is highly uncertain due to limited and conflicting observational evidence. Here we investigate the effects of aerosols on R_ei under different meteorological conditions using 9-year satellite observations. We find that the responses of R_ei to aerosol loadings are modulated by water vapor amount in conjunction with several other meteorological parameters. While there is a significant negative correlation between R_ei and aerosol loading in moist conditions, consistent with the "Twomey effect" for liquid clouds, a strong positive correlation between the two occurs in dry conditions. Simulations based on a cloud parcel model suggest that water vapor modulates the relative importance of different ice nucleation modes, leading to the opposite aerosol impacts between moist and dry conditions. When ice clouds are decomposed into those generated from deep convection and formed in situ, the water vapor modulation remains in effect for both ice cloud types, although the sensitivities of R_ei to aerosols differ noticeably between them due to distinct formation mechanisms. The water vapor modulation can largely explain the difference in the responses of R_ei to aerosol loadings in various seasons. A proper representation of the water vapor modulation is essential for an accurate estimate of aerosol–cloud radiative forcing produced by ice clouds. 

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2. Manually-collected discharge data for multiple inflow tributaries entering Falling Creek Reservoir, Beaverdam Reservoir, and Carvins Cove Reservoir, Virginia, USA from 2019-2023

   https://doi.org/10.6073/pasta/805eb3da2e714f249793d0ff2f11d8f1  

   Carey, Cayelan C; Breef-Pilz, Adrienne; Howard, Dexter W (January 2024, Environmental Data Initiative)

   Discharge rates at multiple inflow streams into Falling Creek Reservoir (Vinton, Virginia, USA), Beaverdam Reservoir (Vinton, Virginia, USA), and Carvins Cove Reservoir (Roanoke, Virginia, USA) were measured manually using multiple methods from 2019-2023. Falling Creek Reservoir, Beaverdam Reservoir, and Carvins Cove Reservoir are owned and operated by the Western Virginia Water Authority as drinking water sources for Roanoke, Virginia. The dataset consists of discharge rates calculated using one of four methods: handheld flowmate, salt injection, velocity float, or bucket method. Data were collected weekly to monthly from February through October 2019 at Falling Creek and Beaverdam Reservoir, approximately monthly at Falling Creek in 2020-2022, approximately monthly at Carvins Cove in 2021-2022, and approximately seasonally in 2023 at Falling Creek and Carvins Cove. 

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3. Manually-collected discharge data for multiple inflow tributaries entering Falling Creek Reservoir, Beaverdam Reservoir, and Carvins Cove Reservoir, Virginia, USA from 2019-2022

   https://doi.org/10.6073/pasta/dd75aba9ea4a87904091c49b77795588  

   Carey, Cayelan C; Breef-Pilz, Adrienne; Howard, Dexter W; Woelmer, Whitney M; Geisler, Beckett; Haynie, George (March 2023, Environmental Data Initiative)

   Discharge rates at multiple inflow streams into Falling Creek Reservoir (Vinton, Virginia, USA), Beaverdam Reservoir (Vinton, Virginia, USA), and Carvins Cove Reservoir (Roanoke, Virginia, USA) were measured manually using multiple methods from 2019-2022. Falling Creek Reservoir, Beaverdam Reservoir, and Carvins Cove Reservoir are owned and operated by the Western Virginia Water Authority as drinking water sources for Roanoke, Virginia. The dataset consists of discharge rates calculated using one of four methods: handheld flowmate, salt injection, velocity float or bucket method. Data were collected weekly to monthly from February through October 2019 at Falling Creek and Beaverdam Reservoir, and approximately monthly at Falling Creek in 2020-2021, and approximately monthly at Carvins Cove in 2021-2022. 

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4. Manually-collected discharge data for multiple inflow and outflow tributaries at Falling Creek Reservoir, Beaverdam Reservoir, and Carvins Cove Reservoir, Virginia, USA from 2019-2024

   https://doi.org/10.6073/pasta/a4289f0a0ae95385c68973e583a2a2f6  

   Carey, Cayelan C; Breef-Pilz, Adrienne; Howard, Dexter W; Bauer, Carly E (January 2025, Environmental Data Initiative)

   Discharge rates at multiple inflow streams into Falling Creek Reservoir (Vinton, Virginia, USA), Beaverdam Reservoir (Vinton, Virginia, USA), Carvins Cove Reservoir (Roanoke, Virginia, USA), and one outflow at Falling Creek Reservoir were measured manually using multiple methods from 2019-2024. Falling Creek Reservoir, Beaverdam Reservoir, and Carvins Cove Reservoir are owned and operated by the Western Virginia Water Authority as drinking water sources for Roanoke, Virginia. The dataset consists of discharge rates calculated using one of four methods: handheld flowmeter, salt injection, velocity float, or bucket method. Data were collected weekly to monthly from February through October 2019 at Falling Creek and Beaverdam Reservoir, and approximately monthly to seasonally at Falling Creek and Carvins Cove from 2020-2024. 

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5. Impact of industrial versus biomass burning aerosols on the Atlantic Meridional Overturning Circulation

   https://doi.org/10.1038/s41612-024-00602-8  

   Allen, Robert J.; Vega, Claire; Yao, Eva; Liu, Wei (March 2024, npj Climate and Atmospheric Science)

   Abstract The ocean’s major circulation system, the Atlantic Meridional Overturning Circulation (AMOC), is slowing down. Such weakening is consistent with warming associated with increasing greenhouse gases, as well as with recent decreases in industrial aerosol pollution. The impact of biomass burning aerosols on the AMOC, however, remains unexplored. Here, we use the Community Earth System Model version 1 Large Ensemble to quantify the impact of both aerosol types on the AMOC. Despite relatively small changes in North Atlantic biomass burning aerosols, significant AMOC evolution occurs, including weakening from 1920 to ~1970 followed by AMOC strengthening. These changes are largely out of phase relative to the corresponding AMOC evolution under industrial aerosols. AMOC responses are initiated by thermal changes in sea surface density flux due to altered shortwave radiation. An additional dynamical mechanism involving the North Atlantic sea-level pressure gradient is important under biomass-burning aerosols. AMOC-induced ocean salinity flux convergence acts as a positive feedback. Our results show that biomass-burning aerosols reinforce early 20th-century AMOC weakening associated with greenhouse gases and also partially mute industrial aerosol impacts on the AMOC. Recent increases in wildfires suggest biomass-burning aerosols may be an important driver of future AMOC variability. 

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