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Marine cloud brightening (MCB) is the deliberate injection of aerosol particles into shallow marine clouds to increase their reflection of solar radiation and reduce the amount of energy absorbed by the climate system. From the physical science perspective, the consensus of a broad international group of scientists is that the viability of MCB will ultimately depend on whether observations and models can robustly assess the scale-up of local-to-global brightening in todays climate and identify strategies that will ensure an equitable geographical distribution of the benefits and risks associated with projected regional changes in temperature and precipitation. To address the physical science knowledge gaps required to assess the societal implications of MCB, we propose a substantial and targeted program of research-field and laboratory experiments, monitoring, and numerical modeling across a range of scales.

Can long-range strike weapons (LRS) create strategic-level effects? Despite extensive debate about the impact of LRS on contemporary warfare, the question of how such weapons can create strategic-level effects has received limited attention. I identify four strategic functions LRS can fulfil to create strategic-level effects: (1) counter-population, (2) strategic interdiction, (3) counter-leadership, and (4) counterforce. By fulfilling these functions, LRS can undermine the will and/or capacity of the adversary to resist at the strategic level of warfare, independent of warfighting efforts located at the tactical and operational levels. I apply these arguments in an analysis of China's conventional missile arsenal and doctrine. My analysis suggests that Chinese leaders believe that employing LRS for strategic functions constitutes a potentially effective way of subduing their enemies. The findings have implications for scholars' and policymakers' understanding of the role of LRS in international politics and contemporary warfare. [ABSTRACT FROM AUTHOR]

Aerosol–cloud interactions modulate the role of clouds in Earth's climate. We derive, evaluate, and apply a simple model to understand aerosol-mediated cloud water adjustments in stratocumulus based on only two prognostic equations for the integrated cloud water L and droplet number concentration N. The model is solved numerically and analytically and agrees well with documented large-eddy-simulation data and satellite retrievals. A tight relationship between adjustments at low and high N is found, revealing the influence of non-precipitation processes (primarily entrainment) on adjustments in precipitating clouds. Furthermore, it is shown that adjustments in non-precipitating clouds tend to be positively biased by external L or N perturbations, while adjustments in precipitating clouds are barely susceptible. By deliberately reducing the complexity of the underlying system, this study constitutes a way forward to facilitate process-level understanding of cloud water adjustments. [ABSTRACT FROM AUTHOR]

We explore the cloud system evolution of non-precipitating marine stratocumuli with a focus on the impacts of the diurnal cycle and free-tropospheric (FT) humidity based on an ensemble of 244 large-eddy simulations generated by perturbing initial thermodynamic profiles and aerosol conditions. Cases are categorized based on their degree of decoupling and the cloud liquid water path (LWPc, based on model columns with cloud optical depths greater than one). A budget analysis method is proposed to analyze the evolution of cloud water in both coupled and decoupled boundary layers. More coupled clouds start with a relatively low LWPc and cloud fraction (fc) but experience the least decrease in LWPc and fc during the daytime. More decoupled clouds undergo greater daytime reduction in LWPc and fc , especially those with higher LWPc at sunrise because they suffer from faster weakening of net radiative cooling. During the nighttime, a positive correlation between FT humidity and the LWPc emerges, consistent with higher FT humidity reducing both radiative cooling and the humidity jump, both of which reduce entrainment and increase LWPc. The LWPc is more likely to decrease during the nighttime for a larger LWPc and greater inversion base height (zi), conditions under which entrainment dominates as turbulence develops. In the morning, the rate of the LWPc reduction depends on the LWPc at sunrise, zi , and the degree of decoupling, with distinct contributions from subsidence and radiation. [ABSTRACT FROM AUTHOR]

Introduction: The impact of cognitive functions on treatment outcomes in forensic psychiatric patients with substance use disorders is not well understood. This study investigates whether neuropsychological deficits, such as in attention, executive functions, and social-emotional cognition, are associated with impulsivity and criminal history. Methods: 109 male patients with substance use disorders at the Clinic for Forensic Psychiatry in Rostock were screened using inclusion and exclusion criteria, with 30 consenting to participate. The tests included the Cambridge Neuropsychological Test Automated Battery (CANTAB) to assess cognitive functions in the areas of attention, psychomotor speed, social and emotional perception, and executive functions, with a particular focus on decision making, planning and problem solving. The Barratt Impulsiveness Scale (BIS-11) was used to measure impulsiveness. Results: Participants displayed significantly higher impulsivity levels on the BIS-11 compared to the general population and showed marked deficits in attention, psychomotor speed, and executive functions. There was a minimal correlation between impulsivity and cognitive performance, suggesting that impulsivity does not directly predict cognitive impairments. Notably, extensive criminal histories correlated with poorer cognitive performance, particularly in tasks requiring planning and problem-solving. Discussion: We found mixed support for the hypothesized associations between neuropsychological functions and criminal histories among patients with substance use disorders. While tasks related to planning and sustained attention showed clearer links, broader cognitive functions displayed inconsistent correlations. These findings emphasize the complexity of the relationship between cognitive deficits, impulsivity, and criminal history, highlighting the necessity for tailored assessments and rehabilitation strategies to enhance outcomes. Future research should focus on larger, longitudinal studies to validate these findings and refine therapeutic approaches. [ABSTRACT FROM AUTHOR]

Mono- and binuclear Cu(I) complexes were isolated employing 2,1,3-benzoselenadiazole (BSeD) as the N-donor ligand, and triphenylphosphine or bis[(2-diphenylphosphino)phenyl] ether (DPEphos) as P-donors. Then, 77Se NMR was measured for the free ligand and the corresponding Cu(I) derivatives, and the related signal was downshifted by 12.86 ppm in the case of [Cu(BSeD)(PPh3)2(ClO4)], and around 15 ppm for the binuclear species. The structure of [Cu(BSeD)(PPh3)2(ClO4)] and [Cu2(μ2-BSeD)(DPEphos)2(ClO4)2] was confirmed by single-crystal X-ray diffraction. The geometry of the Cu(I) complexes was optimized through DFT calculations, and the nature of the Cu···O interaction was investigated through AIM analysis. The three Cu(I) complexes were characterized by intense absorption under 400 nm and, after being excited with blue irradiation, [Cu(BSeD)(PPh3)2(ClO4)] and [Cu2(μ2-BSeD)(PPh3)4(ClO4)2] exhibited weak red emissions centered at 700 nm. The lifetimes comprised between 121 and 159 μs support the involvement of triplet excited states in the emission process. The photoluminescent properties of [Cu(BSeD)(PPh3)2(ClO4)] were supported by TDDFT computations, and the emission was predicted at 710 nm and ascribed to a metal-to-ligand charge transfer (3MLCT) process, in agreement with the experimental data. [ABSTRACT FROM AUTHOR]

Understanding how entrainment and mixing shape the cloud droplet size distribution (DSD) is crucial for understanding the optical properties and precipitation efficiency of clouds. Different mixing scenarios, mainly homogeneous and inhomogeneous, shape the DSD in a distinct way and alter the cloud's impact on climate. However, the prevalence of these mixing scenarios and how they vary in space and time is still uncertain, as underlying processes are commonly unresolved by conventional numerical models. To overcome this challenge, we employ the L3 model, which considers supersaturation fluctuations and turbulent mixing down to the finest relevant lengthscales, making it possible to represent different mixing scenarios realistically. We investigate the spatial and temporal evolution of mixing scenarios over the life cycle of shallow cumulus clouds for varying boundary layer humidities and aerosol concentrations. Our findings suggest homogeneous mixing is generally predominant in cumulus clouds, while different mixing scenarios occur concurrently in the same cloud. Notably, inhomogeneous mixing increases over the cloud life cycle across all analyzed cases. The mean and standard deviation of supersaturation are found to be the most capable indicators of this evolution, providing a comprehensive insight into the characteristics of mixing scenarios. Finally, we show inhomogeneous mixing is more prevalent in drier boundary layers and for higher aerosol concentrations, underscoring the need for a more comprehensive investigation of how these mixing dynamics evolve in a changing climate. Plain Language Summary: Clouds play a crucial role in Earth's climate system by influencing the radiation balance and moisture transfer. When clouds mix with their environment, which occurs during a process known as entrainment and mixing, the number and size of cloud droplets change, affecting cloud optical properties and their ability to precipitate. This mixing can happen in two major ways: either the cloud and environmental air are rapidly mixed (homogeneous mixing) or slowly mixed (inhomogeneous mixing). However, accurately representing these effects, particularly inhomogeneous mixing, is challenging in nearly all atmospheric models, including weather or climate models, as essential scales and processes are unresolved. By applying a high‐resolution model that resolves all essential scales and processes, we investigate how mixing scenarios evolve over the cloud life cycle. We show that while homogeneous mixing prevails, older (mature or dissipating) clouds tend to mix more inhomogeneously. Moreover, clouds in drier and more polluted environments are shown to favor inhomogeneous mixing. In these environments, inhomogeneous mixing becomes the predominant mixing scenario for older clouds, emphasizing the need for further investigations on the impact of different mixing scenarios in a changing climate. Key Points: The evolution of predominant mixing scenarios during the shallow cumulus life cycle is investigatedWhile homogeneous mixing is prevalent, inhomogeneous mixing gradually increases as the cloud agesInhomogeneous mixing is more favored for higher aerosol concentrations and in drier boundary layers [ABSTRACT FROM AUTHOR]

We explore the impacts of the diurnal cycle, free-tropospheric (FT) humidity values, and interactive surface fluxes on the cloud system evolution of non-precipitating marine stratocumuli based on a large ensemble of large-eddy simulations. Cases are separated into three categories based on their degree of decoupling and cloud liquid water path (LWPc). A new budget analysis method is proposed to analyze the evolution of LWPc under both coupled and decoupled conditions. More coupled clouds start with relatively low LWPc and cloud fraction (f c) but experience the least decrease in LWPc and f c during the daytime. More decoupled clouds undergo greater daytime reduction in LWPc and f c, especially those with higher LWPc at sunrise because they suffer from faster weakening of a net radiative cooling. During the nighttime, a positive correlation between FT humidity and LWPc emerges, consistent with higher FT humidity reducing both radiative cooling and the humidity jump, both of which reduce entrainment and increase LWPc. The time rate of change in the LWPc is more likely to be negative for higher LWPc and greater inversion base height (z i), conditions under which entrainment dominates as turbulence develops. In the morning, the rate of the LWPc reduction depends on the LWPc at sunrise, z i, and the degree of decoupling, with distinct contributions from subsidence and radiation. Under well-mixed conditions, it takes about 10 h for the surface fluxes to offset 15 % of the changes in entrainment warming and drying, assuming no changes in transfer coefficients or surface wind speed. [ABSTRACT FROM AUTHOR]