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Advances in Atmospheric Sciences
Journal Prestige (SJR): 0.956
Citation Impact (citeScore): 2
Number of Followers: 42  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 1861-9533 - ISSN (Online) 0256-1530
Published by Springer-Verlag Homepage  [2467 journals]
  • Multi-scale Incremental Analysis Update Scheme and Its Application to
           Typhoon Mangkhut (2018) Prediction

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      Abstract: In the traditional incremental analysis update (IAU) process, all analysis increments are treated as constant forcing in a model’s prognostic equations over a certain time window. This approach effectively reduces high-frequency oscillations introduced by data assimilation. However, as different scales of increments have unique evolutionary speeds and life histories in a numerical model, the traditional IAU scheme cannot fully meet the requirements of short-term forecasting for the damping of high-frequency noise and may even cause systematic drifts. Therefore, a multi-scale IAU scheme is proposed in this paper. Analysis increments were divided into different scale parts using a spatial filtering technique. For each scale increment, the optimal relaxation time in the IAU scheme was determined by the skill of the forecasting results. Finally, different scales of analysis increments were added to the model integration during their optimal relaxation time. The multi-scale IAU scheme can effectively reduce the noise and further improve the balance between large-scale and small-scale increments in the model initialization stage. To evaluate its performance, several numerical experiments were conducted to simulate the path and intensity of Typhoon Mangkhut (2018) and showed that: (1) the multi-scale IAU scheme had an obvious effect on noise control at the initial stage of data assimilation; (2) the optimal relaxation time for large-scale and small-scale increments was estimated as 6 h and 3 h, respectively; (3) the forecast performance of the multi-scale IAU scheme in the prediction of Typhoon Mangkhut (2018) was better than that of the traditional IAU scheme. The results demonstrate the superiority of the multi-scale IAU scheme.
      PubDate: 2023-01-01
       
  • Will the Historic Southeasterly Wind over the Equatorial Pacific in March
           2022 Trigger a Third-year La NiƱa Event'

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      Abstract: Based on the updates of the Climate Prediction Center and International Research Institute for Climate and Society (CPC/IRI) and the China Multi-Model Ensemble (CMME) El Niño-Southern Oscillation (ENSO) Outlook issued in April 2022, La Niña is favored to continue through the boreal summer and fall, indicating a high possibility of a three-year La Niña (2020–23). It would be the first three-year La Niña since the 1998–2001 event, which is the only observed three-year La Niña event since 1980. By examining the status of air—sea fields over the tropical Pacific in March 2022, it can be seen that while the thermocline depths were near average, the southeasterly wind stress was at its strongest since 1980. Here, based on a quaternary linear regression model that includes various relevant air-sea variables over the equatorial Pacific in March, we argue that the historic southeasterly winds over the equatorial Pacific are favorable for the emergence of the third-year La Niña, and both the anomalous easterly and southerly wind stress components are important and contribute ∼50% of the third-year La Niña growth, respectively. Additionally, the possible global climate impacts of this event are discussed.
      PubDate: 2023-01-01
       
  • Estimation of Lightning-Generated NOx in the Mainland of China Based on
           Cloud-to-Ground Lightning Location Data

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      Abstract: Lightning-generated nitrogen oxides (LNOx) have a major influence on the atmosphere and global climate change. Therefore, it is of great importance to obtain a more accurate estimation of LNOx. The aim of this study is to provide a reference for the accurate estimation of the total LNOx in the mainland of China based on cloud-to-ground lightning (CG) location data from 2014 to 2018. The energy of each CG flash was based on the number of return strokes per CG flash, the peak current of each return stroke, and the assumed CG breakdown voltage. The energy of intracloud lightning (IC) was based on the estimated frequencies of IC and the assumed energy of each IC flash. Combining the energy of lightning and the number of nitric oxide (NO) molecules produced by unit energy (ρno), the total LNOx production in the mainland of China was determined. The LNOx in the mainland of China estimated in this study is in the range (0.157–0.321) × 109 kg per year [Tg(N) yr−1], which is on the high end of other scholars’ works. Negative cloud-to-ground lightning (NCG) flashes produce the most moles of NOx, while positive cloud-to-ground lightning (PCG) flashes produce the least total moles of NOx. The breakdown voltage of PCG is greater than that of IC or NCG, while the latter has a greater output of LNOx.
      PubDate: 2023-01-01
       
  • Understanding the Development of the 2018/19 Central Pacific El Niño

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      Abstract: A central Pacific (CP) El Niño event occurred in 2018/19. Previous studies have shown that different mechanisms are responsible for different subtypes of CP El Niño events (CP-I El Niño and CP-II El Niño). By comparing the evolutions of surface winds, ocean temperatures, and heat budgets of the CP-I El Niño, CP-II El Niño, and 2018/19 El Niño, it is illustrated that the subtropical westerly anomalies in the North Pacific, which led to anomalous convergence of Ekman flow and surface warming in the central equatorial Pacific, played an important role in the 2018/19 El Niño event as well as in the CP-II El Niño. Although the off-equatorial forcing played a vital role, it is found that the equatorial forcing acted as a driving (damping) term in boreal spring (summer) of the 2018/19 El Niño. The 2018/19 El Niño provides a timely and vivid example that helps illustrate the proposed mechanism of the CP El Niño, which could be leveraged to improve El Niño predictability.
      PubDate: 2023-01-01
       
  • Detection of Anthropogenic CO2 Emission Signatures with TanSat CO2 and
           with Copernicus Sentinel-5 Precursor (S5P) NO2 Measurements: First Results
           

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      Abstract: China’s first carbon dioxide (CO2) measurement satellite mission, TanSat, was launched in December 2016. This paper introduces the first attempt to detect anthropogenic CO2 emission signatures using CO2 observations from TanSat and NO2 measurements from the TROPOspheric Monitoring Instrument (TROPOMI) onboard the Copernicus Sentinel-5 Precursor (S5P) satellite. We focus our analysis on two selected cases in Tangshan, China and Tokyo, Japan. We found that the TanSat XCO2 measurements have the capability to capture the anthropogenic variations in the plume and have spatial patterns similar to that of the TROPOMI NO2 observations. The linear fit between TanSat XCO2 and TROPOMI NO2 indicates the CO2-to-NO2 ratio of 0.8 × 10−16 ppm (molec cm−2)−1 in Tangshan and 2.3 × 10−16 ppm (molec cm−2)−1 in Tokyo. Our results align with the CO2-to-NOx emission ratios obtained from the EDGAR v6 emission inventory.
      PubDate: 2023-01-01
       
  • Evolution of Meteorological Conditions during a Heavy Air Pollution Event
           under the Influence of Shallow Foehn in Urumqi, China

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      Abstract: The air pollution in Urumqi which is located on the northern slope of the Tianshan Mountains in northwestern China, is very serious in winter. Of particular importance is the influence of terrain-induced shallow foehn, known locally as elevated southeasterly gale (ESEG). It usually modulates atmospheric boundary layer structure and wind field patterns and produces favorable meteorological conditions conducive to hazardous air pollution. During 2013–17, Urumqi had an average of 50 d yr−1 of heavy pollution (daily average PM2.5 concentration >150 µg m−3), of which 41 days were in winter. The majority (71.4%) of heavy pollution processes were associated with the shallow foehn. Based on microwave radiometer, wind profiler, and surface observations, the surface meteorological fields and boundary layer evolution during the worst pollution episode in Urumqi during 16–23 February 2013 are investigated. The results illustrate the significant role of shallow foehn in the building, strengthening, and collapsing of temperature inversions. There were four wind field patterns corresponding to four different phases during the whole pollution event. The most serious pollution phase featured shallow foehn activity in the south of Urumqi city and the appearance of an intense inversion layer below 600 m. Intense convergence caused by foehn and mountain-valley winds was sustained during most of the phase, resulting in pollutants sinking downward to the lower boundary layer and accumulating around urban area. The key indicators of such events identified in this study are highly correlated to particulate matter concentrations and could be used to predict heavy pollution episodes in the feature.
      PubDate: 2023-01-01
       
  • Circulation Patterns Linked to the Positive Sub-Tropical Indian Ocean
           Dipole

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      Abstract: The positive phase of the subtropical Indian Ocean dipole (SIOD) is one of the climatic modes in the subtropical southern Indian Ocean that influences the austral summer inter-annual rainfall variability in parts of southern Africa. This paper examines austral summer rain-bearing circulation types (CTs) in Africa south of the equator that are related to the positive SIOD and the dynamics through which specific rainfall regions in southern Africa can be influenced by this relationship. Four austral summer rain-bearing CTs were obtained. Among the four CTs, the CT that featured (i) enhanced cyclonic activity in the southwest Indian Ocean; (ii) positive widespread rainfall anomaly in the southwest Indian Ocean; and (iii) low-level convergence of moisture fluxes from the tropical South Atlantic Ocean, tropical Indian Ocean, and the southwest Indian Ocean, over the south-central landmass of Africa, was found to be related to the positive SIOD climatic mode. The relationship also implies that positive SIOD can be expected to increase the amplitude and frequency of occurrence of the aforementioned CT. The linkage between the CT related to the positive SIOD and austral summer homogeneous regions of rainfall anomalies in Africa south of the equator showed that it is the principal CT that is related to the inter-annual rainfall variability of the south-central regions of Africa, where the SIOD is already known to significantly influence its rainfall variability. Hence, through the large-scale patterns of atmospheric circulation associated with the CT, the SIOD can influence the spatial distribution and intensity of rainfall over the preferred landmass through enhanced moisture convergence.
      PubDate: 2023-01-01
       
  • The Importance of the Shape Parameter in a Bulk Parameterization Scheme to
           the Evolution of the Cloud Droplet Spectrum during Condensation

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      Abstract: The shape parameter of the Gamma size distribution plays a key role in the evolution of the cloud droplet spectrum in the bulk parameterization schemes. However, due to the inaccurate specification of the shape parameter in the commonly used bulk double-moment schemes, the cloud droplet spectra cannot reasonably be described during the condensation process. Therefore, a newly-developed triple-parameter condensation scheme with the shape parameter diagnosed through the number concentration, cloud water content, and reflectivity factor of cloud droplets can be applied to improve the evolution of the cloud droplet spectrum. The simulation with the new parameterization scheme was compared to those with a high-resolution Lagrangian bin scheme, the double-moment schemes in a parcel model, and the observation in a 1.5D Eulerian model that consists of two cylinders. The new scheme with the shape parameter varying with time and space can accurately simulate the evolution of the cloud droplet spectrum. Furthermore, the volume-mean radius and cloud water content simulated with the new scheme match the Lagrangian analytical solutions well, and the errors are steady, within approximately 0.2%.
      PubDate: 2023-01-01
       
  • Alternation of the Atmospheric Teleconnections Associated with the
           Northeast China Spring Rainfall during a Recent 60-Year Period

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      Abstract: Northeast China (NEC) is China’s national grain production base, and the local precipitation is vital for agriculture during the springtime. Therefore, understanding the dynamic origins of the NEC spring rainfall (NECSR) variability is of socioeconomic importance. This study reveals an interdecadal change in the atmospheric teleconnections associated with the NECSR during a recent 60-year period (1961–2020). Before the mid-1980s, NECSR had been related to a Rossby wave train that is coupled with extratropical North Atlantic sea surface temperature (SST), whereas, since the mid-1980s, NECSR has been linked to a quite different Rossby wave train that is coupled with tropical North Atlantic SST. Both Rossby wave trains could lead to enhanced NECSR through anomalous cyclones over East Asia. The weakening of the westerly jet over North America is found to be mainly responsible for the alternation of the atmospheric teleconnections associated with NECSR during two epochs.
      PubDate: 2023-01-01
       
  • Assimilation of Ocean Surface Wind Data by the HY-2B Satellite in GRAPES:
           Impacts on Analyses and Forecasts

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      Abstract: The ocean surface wind (OSW) data retrieved from microwave scatterometers have high spatial accuracy and represent the only wind data assimilated by global numerical models on the ocean surface, thus playing an important role in improving the forecast skills of global medium-range weather prediction models. To improve the forecast skills of the Global/Regional Assimilation and Prediction System Global Forecast System (GRAPES_GFS), the HY-2B OSW data is assimilated into the GRAPES_GFS four-dimensional variational assimilation (4DVAR) system. Then, the impacts of the HY-2B OSW data assimilation on the analyses and forecasts of GRAPES_GFS are analyzed based on one-month assimilation cycle experiments. The results show that after assimilating the HY-2B OSW data, the analysis errors of the wind fields in the lower-middle troposphere (1000–600 hPa) of the tropics and the southern hemisphere (SH) are significantly reduced by an average rate of about 5%. The impacts of the HY-2B OSW data assimilation on the analysis fields of wind, geopotential height, and temperature are not solely limited to the boundary layer but also extend throughout the entire troposphere after about two days of cycling assimilation. Furthermore, assimilating the HY-2B OSW data can significantly improve the forecast skill of wind, geopotential height, and temperature in the troposphere of the tropics and SH.
      PubDate: 2023-01-01
       
  • Unprecedented Heatwave in Western North America during Late June of 2021:
           Roles of Atmospheric Circulation and Global Warming

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      Abstract: An extraordinary and unprecedented heatwave swept across western North America (i.e., the Pacific Northwest) in late June of 2021, resulting in hundreds of deaths, a massive die-off of sea creatures off the coast, and horrific wildfires. Here, we use observational data to find the atmospheric circulation variabilities of the North Pacific and Arctic-Pacific-Canada patterns that co-occurred with the development and mature phases of the heatwave, as well as the North America pattern, which coincided with the decaying and eastward movement of the heatwave. Climate models from the Coupled Model Intercomparison Project (Phase 6) are not designed to simulate a particular heatwave event like this one. Still, models show that greenhouse gases are the main reason for the long-term increase of average daily maximum temperature in western North America in the past and future.
      PubDate: 2023-01-01
       
  • Changes in Water Use Efficiency Caused by Climate Change, CO2
           Fertilization, and Land Use Changes on the Tibetan Plateau

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      Abstract: Terrestrial ecosystem water use efficiency (WUE) is an important indicator for coupling plant photosynthesis and transpiration, and is also a key factor linking the carbon and water cycles between the land and atmosphere. However, under the combination of climate change and human intervention, the change in WUE is still unclear, especially on the Tibetan Plateau (TP). Therefore, satellite remote sensing data and process-based terrestrial biosphere models (TBMs) are used in this study to investigate the spatiotemporal variations of WUE over the TP from 2001 to 2010. Then, the effects of land use and land cover change (LULCC) and CO2 fertilization on WUE from 1981–2010 are assessed using TBMs. Results show that climate change is the leading contributor to the change in WUE on the TP, and temperature is the most important factor. LULCC makes a negative contribution to WUE (−20.63%), which is greater than the positive contribution of CO2 fertilization (11.65%). In addition, CO2 fertilization can effectively improve ecosystem resilience on the TP. On the northwest plateau, the effects of LULCC and CO2 fertilization on WUE are more pronounced during the driest years than the annual average. These findings can help researchers understand the response of WUE to climate change and human activity and the coupling of the carbon and water cycles over the TP.
      PubDate: 2023-01-01
       
  • The Coordinated Influence of Indian Ocean Sea Surface Temperature and
           Arctic Sea Ice on Anomalous Northeast China Cold Vortex Activities with
           Different Paths during Late Summer

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      Abstract: The Northeast China cold vortex (NCCV) during late summer (from July to August) is identified and classified into three types in terms of its movement path using machine learning. The relationships of the three types of NCCV intensity with atmospheric circulations in late summer, the sea surface temperature (SST), and Arctic sea ice concentration (SIC) in the preceding months, are analyzed. The sensitivity tests by the Community Atmosphere Model version 5.3 (CAM5.3) are used to verify the statistical results. The results show that the coordination pattern of East Asia-Pacific (EAP) and Lake Baikal high pressure forced by SST anomalies in the North Indian Ocean dipole mode (NIOD) during the preceding April and SIC anomalies in the Nansen Basin during the preceding June results in an intensity anomaly for the first type of NCCV. While the pattern of high pressure over the Urals and Okhotsk Sea and low pressure over Lake Baikal during late summer—which is forced by SST anomalies in the South Indian Ocean dipole mode (SIOD) in the preceding June and SIC anomalies in the Barents Sea in the preceding April—causes the intensity anomaly of the second type. The third type is atypical and is not analyzed in detail. Sensitivity tests, jointly forced by the SST and SIC in the preceding period, can well reproduce the observations. In contrast, the results forced separately by the SST and SIC are poor, indicating that the NCCV during late summer is likely influenced by the coordinated effects of both SST and SIC in the preceding months.
      PubDate: 2023-01-01
       
  • Kinetic Energy Budgets during the Rapid Intensification of Typhoon
           Rammasun (2014)

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      Abstract: In this study, Typhoon Rammasun (2014) was simulated using the Weather Research and Forecasting model to examine the kinetic energy during rapid intensification (RI). Budget analyses revealed that in the inner area of the typhoon, the conversion from symmetric divergent kinetic energy associated with the collocation of strong cyclonic circulation and inward flow led to an increase in the symmetric rotational kinetic energy in the lower troposphere. The increase in the symmetric rotational kinetic energy in the mid and upper troposphere resulted from the upward transport of symmetric rotational kinetic energy from the lower troposphere. In the outer area, both typhoon and Earth’s rotation played equally important roles in the conversion from symmetric divergent kinetic energy to symmetric rotational kinetic energy in the lower troposphere. The decrease in the symmetric rotational kinetic energy in the upper troposphere was caused by the conversion to asymmetric rotational kinetic energy through the collocation of symmetric tangential rotational winds and the radial advection of asymmetric tangential rotational winds by radial environmental winds.
      PubDate: 2023-01-01
       
  • New Progress and Challenges in Cloud-Aerosol-Radiation-Precipitation
           Interactions: Preface for a Special Issue

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      PubDate: 2022-12-01
       
  • Decomposition of Fast and Slow Cloud Responses to Quadrupled CO2 Forcing
           in BCC-AGCM2.0 over East Asia

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      Abstract: In this study, the decomposed fast and slow responses of clouds to an abruptly quadrupled CO2 concentration (approximately 1139 ppmv) in East Asia (EA) are obtained quantitatively by using a general circulation model, BCC–AGCM2.0. Our results show that in the total response, the total cloud cover (TCC), low cloud cover (LCC), and high cloud cover (HCC) all increased north of 40°N and decreased south of 40°N except in the Tibetan Plateau (TP). The mean changes of the TCC, LCC, and HCC in EA were −0.74%, 0.38%, and −0.38% in the total response, respectively; 1.05%, −0.03%, and 1.63% in the fast response, respectively; and −1.79%, 0.41%, and −2.01% in the slow response, respectively. By comparison, we found that changes in cloud cover were dominated by the slow response in most areas in EA due to the changes in atmospheric temperature, circulation, and water vapor supply together. Overall, the changes in the cloud forcing over EA related to the fast and slow responses were opposite to each other, and the final cloud forcing was dominated by the slow response. The mean net cloud forcing (NCF) in the total response over EA was −1.80 W m−2, indicating a cooling effect which partially offset the warming effect caused by the quadrupled CO2. The total responses of NCF in the TP, south China (SC), and northeast China (NE) were −6.74 W m−2, 6.11 W m−2, and −7.49 W m−2, respectively. Thus, the local effects of offsetting or amplifying warming were particularly obvious.
      PubDate: 2022-12-01
       
  • Application of a Neural Network to Store and Compute the Optical
           Properties of Non-Spherical Particles

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      Abstract: Radiative transfer simulations and remote sensing studies fundamentally require accurate and efficient computation of the optical properties of non-spherical particles. This paper proposes a deep learning (DL) scheme in conjunction with an optical property database to achieve this goal. Deep neural network (DNN) architectures were obtained from a dataset of the optical properties of super-spheroids with extensive shape parameters, size parameters, and refractive indices. The dataset was computed through the invariant imbedding T-matrix method. Four separate DNN architectures were created to compute the extinction efficiency factor, single-scattering albedo, asymmetry factor, and phase matrix. The criterion for designing these neural networks was the achievement of the highest prediction accuracy with minimal DNN parameters. The numerical results demonstrate that the determination coefficients are greater than 0.999 between the prediction values from the neural networks and the truth values from the database, which indicates that the DNN can reproduce the optical properties in the dataset with high accuracy. In addition, the DNN model can robustly predict the optical properties of particles with high accuracy for shape parameters or refractive indices that are unavailable in the database. Importantly, the ratio of the database size (∼127 GB) to that of the DNN parameters (∼20 MB) is approximately 6810, implying that the DNN model can be treated as a highly compressed database that can be used as an alternative to the original database for real-time computing of the optical properties of non-spherical particles in radiative transfer and atmospheric models.
      PubDate: 2022-12-01
       
  • Characteristics of Pre-summer Daytime Cloud Regimes over Coastal South
           China from the Himawari-8 Satellite

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      Abstract: Using the high spatiotemporal resolution (2 km-and-10 min) data from the Advanced Himawari Imager onboard the Himawari-8 satellite, this study documents the fine-scale characteristics of daytime cloud regimes (CRs) over coastal South China during the pre-summer rainy season (April–June). Six CRs (CR1–CR6) are identified based on the joint frequency distribution of cloud top brightness temperature and cloud optical thickness, namely, the optically thin-to-moderate cloud mixture, optically thin warm clouds with cirrus, optically thick warm clouds, weak convective cloud mixture, strong convective clouds, and extreme, deep convective clouds. The optically thick warm clouds are the major CR during April and May, with higher frequencies over land, especially along the urban agglomeration, rather than the offshore which may be an indicator of the higher aerosol concentrations being a contributing factor over the cities. The CRs with weak convective cloud mixtures and strong convective clouds appear more frequently over the land, while the two CRs with optically thinner clouds occur mainly offshore. Synoptic flow patterns (SPs) are objectively identified and examined focusing on those favoring the two major rain-producing CRs (CR5 and CR6) and the highly reflective CR with optically thick warm clouds (CR3). The two SPs favoring CR5 and CR6 are characterized by abundant moisture with low-level jets after monsoon onset, and a northwest high-southeast low pattern with strong dynamic convergence along the coastline, respectively. The non-convective CR3 with high reflectance is related to a SP that features the western North Pacific subtropical high extending more westward, leading to a moderate moisture supply and a wide range of convective available potential energy, but also, large convective inhibition.
      PubDate: 2022-12-01
       
  • Identification of Convective and Stratiform Clouds Based on the Improved
           DBSCAN Clustering Algorithm

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      Abstract: A convective and stratiform cloud classification method for weather radar is proposed based on the density-based spatial clustering of applications with noise (DBSCAN) algorithm. To identify convective and stratiform clouds in different developmental phases, two-dimensional (2D) and three-dimensional (3D) models are proposed by applying reflectivity factors at 0.5° and at 0.5°, 1.5°, and 2.4° elevation angles, respectively. According to the thresholds of the algorithm, which include echo intensity, the echo top height of 35 dBZ (ET), density threshold, and ε neighborhood, cloud clusters can be marked into four types: deep-convective cloud (DCC), shallow-convective cloud (SCC), hybrid convective-stratiform cloud (HCS), and stratiform cloud (SFC) types. Each cloud cluster type is further identified as a core area and boundary area, which can provide more abundant cloud structure information. The algorithm is verified using the volume scan data observed with new-generation S-band weather radars in Nanjing, Xuzhou, and Qingdao. The results show that cloud clusters can be intuitively identified as core and boundary points, which change in area continuously during the process of convective evolution, by the improved DBSCAN algorithm. Therefore, the occurrence and disappearance of convective weather can be estimated in advance by observing the changes of the classification. Because density thresholds are different and multiple elevations are utilized in the 3D model, the identified echo types and areas are dissimilar between the 2D and 3D models. The 3D model identifies larger convective and stratiform clouds than the 2D model. However, the developing convective clouds of small areas at lower heights cannot be identified with the 3D model because they are covered by thick stratiform clouds. In addition, the 3D model can avoid the influence of the melting layer and better suggest convective clouds in the developmental stage.
      PubDate: 2022-12-01
       
  • Evaluating the Impacts of Cloud Microphysical and Overlap Parameters on
           Simulated Clouds in Global Climate Models

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      Abstract: The improvement of the accuracy of simulated cloud-related variables, such as the cloud fraction, in global climate models (GCMs) is still a challenging problem in climate modeling. In this study, the influence of cloud microphysics schemes (one-moment versus two-moment schemes) and cloud overlap methods (observation-based versus a fixed vertical decorrelation length) on the simulated cloud fraction was assessed in the BCC_AGCM2.0_CUACE/Aero. Compared with the fixed decorrelation length method, the observation-based approach produced a significantly improved cloud fraction both globally and for four representative regions. The utilization of a two-moment cloud microphysics scheme, on the other hand, notably improved the simulated cloud fraction compared with the one-moment scheme; specifically, the relative bias in the global mean total cloud fraction decreased by 42.9%–84.8%. Furthermore, the total cloud fraction bias decreased by 6.6% in the boreal winter (DJF) and 1.64% in the boreal summer (JJA). Cloud radiative forcing globally and in the four regions improved by 0.3%–1.2% and 0.2%–2.0%, respectively. Thus, our results showed that the interaction between clouds and climate through microphysical and radiation processes is a key contributor to simulation uncertainty.
      PubDate: 2022-12-01
       
 
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