Chunsong Lu

• Homepage: http://fight9898.wixsite.com/chunsonglu
• Professor (Full) at Nanjing University of Information Science and Technology

The Tibetan Plateau (TP) significantly impacts the global climate. TP's unique geographical conditions make it one of the areas with the largest precipitation biases in numerical models. The overestimation and distribution biases of precipitation in models are closely related to the parameterization of convection processes over the TP. In light of...

Turbulent entrainment‐mixing processes profoundly influence the relationship between radar reflectivity factor and liquid water content (Z‐LWC) of cloud droplets. However, quantification of the entrainment‐mixing mechanisms based on the Z‐LWC relationship is still lacking. To address this gap, 12,218 entrainment‐mixing cases are simulated using the...

Plain Language Summary Clouds play a crucial role in regulating Earth's climate, and understanding how they form and evolve is important for accurate weather and climate predictions. One key process affecting cloud development is entrainment, where drier air from outside the cloud mixes into the cloud, influencing its growth. Scientists know that a...

Different turbulent entrainment‐mixing mechanisms between clouds and environment are essential to cloud‐related processes; however, accurate representation of entrainment‐mixing in weather/climate models still poses a challenge. This study exploits the use of machine learning (ML) to address this challenge. Four ML (Light Gradient Boosting Machine...

The Sichuan-Xizang Railway is an important part of the railway network in China, and geological disasters, such as mountain floods and landslides, frequently occur in this region. Precipitation is an important cause of these disasters; therefore, accurate simulation of the precipitation in this region is highly important. In this study, the descrip...

The characteristics of summertime raindrop size distribution (DSD) and associated relations in the semi-arid region over the Inner Mongolian Plateau (IMP) were investigated, utilizing five-year continuous observations by a PARSIVEL2 disdrometer in East Ujimqin County (EUC), China. It is found that only 7.94% of the 15 664 one-min precipitation samp...

The East Asian summer monsoon (EASM) region, teeming with anthropogenic black carbon (BC), lacks clarity on the fast and slow responses of EASM precipitation and other atmospheric water cycle processes to BC forcings. Through Community Earth System Model, version 1, simulations with an atmospheric water tracking (AWT) method, fast atmospheric adjus...

The influence of anthropogenic aerosols on cloud formation and precipitation, through their effects on cloud microphysics and thermodynamics, is crucial for understanding the environmental impacts of human activities. This study uses the WRF-Chem model to simulate a mixed-phase cloud precipitation event during the early Meiyu season over the Yangtz...

Plain Language Summary Understanding how clouds behave is key to improving weather forecasts and climate models. Entrainment and detrainment rates describe how cumulus clouds interact with the atmosphere, and are key parameters in numerical models. While satellite data have been used to estimate entrainment rates, estimating detrainment rates from...

Cloud condensation nuclei (CCN) activation plays a crucial role in regional cloud-precipitation and global climate. However, inaccuracies in CCN activation parameterization, stemming from the presence of unactivated particles in CCN measurements that are mistakenly included in developing CCN activation parameterizations, can introduce biases in mod...

Northwest China (NWC), is characterized by its arid and semi-arid environment, and exhibits high sensitivity to precipitation variations. Recent research indicates a wetting tendency over NWC, yet quantifying its moisture source remains challenging. Here, employing a 40 year simulation with Community Atmosphere Model version 5.1 (CAM5.1) coupled to...

This study investigates the influence of airflow transport pathways on seasonal rainfall in the mountainous region of the Liupan Mountains (LM) during the rainy seasons from 2020 to 2022, utilizing observational data from seven ground gradient stations located on the eastern slopes, western slopes, and mountaintops combined with backward trajectory...

Plain Language Summary Mixed‐phase clouds consist of water vapor, supercooled droplets, and ice particles. The complex liquid‐ice interactions have a substantial influence on the macrophysical and microphysical characteristics of the clouds, which ultimately affect the global water cycle and radiative balance. Observations and model experiments hav...

The super-droplet method (SDM) is a Lagrangian particle-based numerical scheme for cloud microphysics. In this work, a series of simulations based on the DYCOMS-II (RF02) setup with different horizontal and vertical resolutions are conducted to explore the grid convergence of the SDM simulations of marine stratocumulus. The results are compared wit...

Entrainment and detrainment rates (ε and δ) constitute the most critical free parameters in mass flux schemes commonly employed for cumulus parameterizations. Recently, Zhu et al. (2021) introduced a new approach that utilizes aircraft observations to simultaneously estimate ε and δ for cumulus clouds, overcoming the limitation of other observation...

Mixed‐phase stratiform clouds contain numerous liquid, mixed‐phase, and ice clusters, quantifying the cluster scales is potentially helpful to improve the parameterizations of microphysics and radiation models. However, the scales of hydrometeor clusters at different levels of stratiform clouds are not well understood. In this study, using airborne...

As one of important large-scale systems in south Asia, the Indian summer monsoon (ISM) can affect the moisture budget and cloud processes over the Tibetan Plateau (TP). The influneces of ISM on cloud and precipitation of the Eastern TP (ETP) are discussed via a cloud-resolving model. The outbreak of ISM can activate the moisture transport between T...

Since the distinct thermostability difference of sulfate ammonium and nitrate ammonium aerosols, their distributions, evolutions and sources could be unpredictable on a long‐range transport condition. Here, we highlighted the 3‐D structures and sources of SO4²⁻, NO3⁻ and NH4⁺ (SNA) during two cold front episodes in east China. Cold fronts effective...

Plain Language Summary Entrainment‐mixing is one of the key processes controlling cloud life cycle and the spatial distribution of hydrometeor. It is known that inhomogeneous entrainment mixing would enhance the clustering of particle distribution in cumulus clouds, but the scales of droplet and ice clusters induced by inhomogeneous entrainment hav...

Entrainment-mixing processes of fog with the surrounding ambient air are extremely intricate and impose significant effects on the microphysical and radiative properties of fog. However, it is difficult to utilize the default Thompson scheme of the atmospheric chemistry model GRAPES_Meso5.1/CUACE to examine the effects of different entrainment-mixi...

The Northwest China (NWC) is located in an arid and semi-arid inland region, making its ecosystem highly vulnerable to changes of precipitation. Previous studies have revealed the wetting trend and potential moisture sources of the NWC, while not clearly quantified the moisture (water vapor and precipitation) sources and its interannual variability...

As an essential moisture transport channel over the Tibetan Plateau (TP), accurate simulation of precipitation over the southeastern TP (SETP) is crucial for downstream moisture transport and water resource assessment. To improve SETP’s precipitation simulation accuracy, a Turbulent Orographic Form Drag (TOFD) scheme, which represents the TOFD effe...

Cloud lifecycles are influenced by interactions among clouds and mixing with cloud‐free environments. Cloud shapes dictate the length of cloud boundaries, which affects these interactions. This study uses a large eddy simulation to examine the relationships between the shallow cumulus cloud shapes, processes at their boundaries, and lifecycles. To...

Plain Language Summary In mixed‐phase clouds, the coexistence of liquid and ice has significant impacts on the cloud lifecycle and radiative properties, but the phase partitioning in mixed‐phase cloud is still not fully understood. In cumulus clouds, one of the major factors controlling the microphysics across cloud edges is the entrainment of dry...

Aerosol–cloud interaction (ACI) in fog and planetary boundary layer (PBL) conditions plays critical roles in the fog life cycle. However, it is not clear how ACI in the first fog (Fog1) affects the PBL and subsequently affects ACI in the second fog (Fog2), which is important information for understanding the interaction between ACI and the PBL, as...

The process of entrainment-mixing between cumulus clouds and the ambient air is important for the development of cumulus clouds. Accurately obtaining the entrainment rate (λ) is particularly important for its parameterization within the overall cumulus parameterization scheme. In this study, an improved bulk-plume method is proposed by solving the...

Relative dispersion (ɛ) is a key expression used to parameterize various cloud processes in global circulation models (GCMs) and meteorological mesoscale models. Aerosols, updraft velocity (w), and different growth stages of warm clouds are known to affect relative dispersion. A two-dimensional detailed bin microphysical cloud model is used to inve...

Cloud microphysical processes occur at the smallest end of scales among cloud-related processes and thus must be parameterized not only in large-scale global circulation models (GCMs) but also in various higher-resolution limited-area models such as cloud-resolving models (CRMs) and large-eddy simulation (LES) models. Instead of giving a comprehens...

Understanding cloud droplet relative dispersion is critical for mitigating the confounding effect of aerosol‐cloud interactions in the simulation of the global climatic patterns. Diverse dispersion effects, meaning that the correlation between relative dispersion (ε) and fog droplet number concentration (Nf) changes from positive to negative as Nf...

Marine stratocumulus clouds play an important role in the planet’s radiation budget by reflecting the incident solar radiation. Some studies have shown that the uncertainty in temperature projections in global warming simulations is mainly caused by the representation of marine low clouds in global climate models. Using the Super Droplet Method (SD...

The characteristics of the raindrop size distribution (DSD) during regional freezing rain (FR) events that occur throughout the phase change (from liquid to solid) are poorly understood due to limited observations. We investigate the evolution of microphysical parameters and the key formation mechanisms of regional FR using the DSDs from five disdr...

Desert dust and sand storms from the Sahara can sometimes be transported thousands of kilometers, causing social and economic damages throughout their path, deteriorating the air quality, and affecting human health. The seasonal climatology and transport pathways of dust aerosols are, therefore, essential to a deeper understanding of the impact of...

Aerosol–fog interactions (AFIs) play pivotal roles in the fog cycle. However, few studies have focused on the differences in AFIs between two successive radiation fog events and the underlying mechanisms. To fill this knowledge gap, our study simulates two successive radiation fog events in the Yangtze River Delta, China, using the Weather Research...

A field campaign in Liupan Mountains was carried out by the Weather Modification Center of the China Meteorological Administration to study the impact of terrain on precipitation in Northwest China. The vertical structures and microphysical characteristics of a mixed cloud and precipitation process, which means stratiform clouds with embedded conve...

Understanding aerosol particle activation is essential for evaluating aerosol indirect effects (AIEs) on climate. Long-term measurements of aerosol particle activation help to understand the AIEs and narrow down the uncertainties of AIEs simulation. However, they are still scarce. In this study, more than 4 years of comprehensive aerosol measuremen...

The impacts of the ice-crystal size distribution shape parameter (μi) were considered in the two-moment bulk cloud microphysics scheme of the Community Atmosphere Model Version 6 (CAM6). The μi's impact on the statistical mean radii of ice crystals can be analyzed based on their calculating formulas. Under the same mass (qi) and number (Ni), the ra...

In this study, the aerosol optical depth (AOD) from the Moderate Resolution Imaging Spectroradiometer (MODIS) Collection 6.1 (C6.1) product was compared with ground-based measurements at five sites of the Aerosol Robotic Network (AERONET) in North Africa. The MODIS AOD showed a good correlation coefficient of ~0.78, a very small mean bias error of...

The relationships between mean terminal velocity and volume mean diameter of different hydrometeors, as well as how they change with different background aerosol concentrations have been investigated with numerical simulations of tropical deep convection from the Weather Forecast and Research Model (WRF), coupled with spectral bin microphysics. The...

Cloud microphysical properties are significantly affected by entrainment and mixing processes. However, it is unclear how the entrainment rate affects the relative dispersion of cloud droplet size distribution. Previously, the relationship between relative dispersion and entrainment rate was found to be positive or negative. To reconcile the contra...

Using the Weather Research and Forecasting (WRF) model, a series of sensitivity experiments were conducted to study the individual and overall effects of the various topographic uplifts of the Tibetan Plateau (TP) on regional climate variability. The presence of the southern slope of the TP facilitates the maintenance and development of the South A...

Understanding aerosol particle activation is essential for evaluating aerosol 14 indirect effects (AIEs) on climate. Long-term measurements on aerosol particle 15 activation help to understand the AIEs and narrow down the uncertainties of AIEs 16 simulation; however, they are still scarce. In this study, more than 4-year aerosol 17 comprehensive me...

The impacts of the ice crystal size distribution shape parameter (μi) were considered in the two-moment bulk cloud microphysics scheme of the Community Atmosphere Model Version 6 (CAM6). The calculating formulas of statistical mean radii indicate that, under the same mass (qi) and number (Ni) of ice crystals, the ratios of the mass-weighted radius...

The entrainment rate (λ) is difficult to estimate, and its uncertainties cause a significant error in convection parameterization and precipitation simulation, especially over the Tibetan Plateau, where observations are scarce. The λ over the Tibetan Plateau, and its adjacent regions, is estimated for the first time using five-year satellite data a...

Different entrainment–mixing processes can occur in clouds; however, a homogeneous mixing mechanism is often implicitly assumed in most commonly used microphysics schemes. Here, we first present a new entrainment–mixing parameterization that uses the grid mean relative humidity without requiring the relative humidity of the entrained air. Then, the...

The current study used seven optimization algorithms such as stochastic gradient descent (SGD), root mean square propagation (RMSprop), adaptive grad (AdaGrad), adaptive delta (AdaDelta), adaptive moment estimation (Adam), adaptive maximum (Adamax), and Nesterov-accelerated adaptive moment estimation (Nadam) and eight learning rates (1, 0.1, 0.01,...

Both the stratiform and convective regions play important roles in the development of mesoscale convective systems (MCSs). In this study, the impacts of hydrometeors and water vapor in stratiform region on the evolution of MCSs during a heavy rainfall event over South China are investigated by the Weather Research and Forecasting (WRF) model with T...

Spatial and temporal variation of aerosol optical depth (AOD) and optical depth of different aerosol types derived from the second Modern-Era Retrospective analysis for Research and Applications (MERRA-2) over the South China Sea (SCS) between 1980 and 2020 were studied. AOD distribution showed different characteristics throughout the entire SCS. S...

This study examines the vertical variations of cloud microphysical relationships and their implications to cloud microphysical processes in marine stratocumulus clouds using in‐situ aircraft observations during the Aerosol and Cloud Experiments in Eastern North Atlantic (ACE‐ENA) field campaign. A new diagram with a coordinate system based on cloud...

Spectral relative dispersion of different hydrometeors is vital to accurately describe sedimentation. Here, the Weather Research and Forecasting model with spectral bin microphysics is used to simulate convective clouds in Shouxian of Anhui province in China to study the spectral relative dispersion of different hydrometeors. Firstly, regardless of...

Different entrainment-mixing processes can occur in clouds; however, a homogeneous mixing mechanism is often implicitly assumed in most commonly used microphysics schemes. Here, we first present a new entrainment-mixing parameterization that uses the grid-mean relative humidity without requiring the relative humidity of the entrained air. Second, t...

We conducted a three-month field experiment focusing on the physical and chemical characteristics of fog in a tropical rainforest in Xishuangbanna, Southwest China, in the winter of 2019. In general, the fog would form at midnight and persist because of the increased long-wave radiative cooling combined with the high relative humidity, gentle breez...

The seasonal and diurnal variations of cloud systems are profoundly affected by the large-scale and local environments. In this study, a one-year-long simulation was conducted using a two-dimensional cloud-resolving model over the Eastern Tibetan Plateau (ETP) and two subregions of Eastern China: Southern East China and Central East China. Deep con...

The precipitation is divided into the warm-rain and cold-rain processes according to the microphysical mechanism, but which processes are more important in a heavy precipitation even? An approach that quantitatively separates the warm-rain from total-rain processes is proposed by adding a set of new variables in microphysics schemes of the Weather...

A new approach is developed for estimating entrainment and detrainment rates in cumulus clouds based on aircraft observations. Equations relating entrainment and detrainment rates to gross entrainment and detrainment are derived. This approach is applied to the Holistic Interactions of Shallow Clouds, Aerosols, and Land‐Ecosystems field campaign, s...

The parameterization of cloud entrainment rate has been problematic for many years, hindering the accurate representation of convective processes in large‐scale models. Here, we extend our previous work on individual shallow convection to ensemble deep convection. Entrainment rate is estimated based on three‐dimensional convective clouds from Augus...

Different entrainment-mixing processes of turbulence are crucial to processes related to clouds; however, only a few qualitative studies have been concentrated on the vertical distributions of entrainment-mixing mechanisms with low vertical resolutions. To quantitatively study vertical profiles of entrainment-mixing mechanisms with a high resolutio...

With their extensive coverage, marine low clouds greatly impact global climate. Presently, marine low clouds are poorly represented in global climate models, and the response of marine low clouds to changes in atmospheric greenhouse gases and aerosols remains the major source of uncertainty in climate simulations. The Eastern North Atlantic (ENA) i...

Entrainment‐mixing process significantly affects cloud micro/macrophysics and the evaluation of aerosol indirect effects. However, it is still an open question as to how to quantify entrainment‐mixing mechanism for broad cloud droplet size distributions (CDSDs). Here, CDSDs with different spectral widths are used to initialize the Explicit Mixing P...

A three‐dimensional variational (3DVAR) data assimilation method for the aerosol variables of the community multiscale air quality (CMAQ) model was developed. This 3DVAR system uses PM2.5 and PM2.5‐10 (the difference between PM10 and PM2.5) as control variables and used the AERO6 aerosol chemical mechanism in the CMAQ model. Two parallel experiment...

Different entrainment-mixing processes of turbulence are crucial to processes related to clouds; however, only a few qualitative studies have been concentrated on the vertical distributions of entrainment-mixing mechanisms with low vertical resolutions. To quantitatively study vertical profiles of entrainment-mixing mechanisms with a high resolutio...

In part I, the clear air echo in front of the squall line is caused by turbulence diffraction, which makes the ZDR echo characteristics different from particle scattering. To study the turbulence deformation phenomenon that is affected by environmental wind, the turbulence-related method is used to analyze the characteristics of three-dimensional t...

A flight of shallow convective clouds during the SCMS95 (Small Cumulus Microphysics Study 1995) observation project is simulated by the large eddy simulation (LES) version of the Weather Research and Forecasting Model (WRF-LES) with spectral bin microphysics (SBM). This study focuses on relative dispersion of cloud droplet size distributions, since...

Marine stratocumulus clouds contribute significantly to the Earth's radiation budget due to their extensive coverage and high albedo. Yet, subgrid variability in cloud properties, such as aerosol concentration, droplet number, and precipitation rates, lead to considerable errors in global climate models. While these clouds usually have small vertic...

Unactivated particles mixed in cloud condensation nuclei (CCN) measurements lead to inaccurate activation parameterization, thereby overestimating aerosol indirect effects in current models. Data from five CCN field campaigns in Eastern China are analyzed to identify unactivated particles. The lower temperature, lower aerosol hygroscopicity (κ), an...

Plain Language Summary Aerosols, the suspensions of solid or liquid particles in the air, affect clouds through aerosol–cloud interaction (ACI) and aerosol–radiation interaction (ARI). The ARI refers to that aerosols affect the meteorological conditions in clouds by scattering and absorbing radiation. The ACI refers to that clouds form on aerosols...

Ambient exposure to particulate matter (PM) air pollution is known to have an adverse effect on public health worldwide. Rapid increase rates of economic and urbanization, industrial development, and environmental change in China have exacerbated the occurrence of air pollution. This study examines the temporal and spatial distribution of PM on nat...

Entrainment‐mixing mechanisms significantly affect cloud droplet number concentration, radius, and spectral shape. Quantitative examination of entrainment‐mixing effects on cloud droplet spectral width is lacking. This study examines the effects of entrainment‐mixing processes on cloud microphysics by 12,218 different setups, each simulated 10 time...

Numerical simulations often overpredict precipitation over the Tibetan Plateau (TP). To examine the factors causing precipitation overprediction, different parameterizations of liquid‐phase microphysical processes (accretion, autoconversion, and entrainment mixing) are implemented into the Morrison microphysics scheme to simulate a TP precipitation...