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Objective: To design a multifunctional cooking experimental platform with negative pressure and superheated steam, providing consumers with greener, healthier, and more diverse cooking methods. Methods: The research status of integrated cooking equipment was analyzed, and the application status of superheated steam and negative pressure technology in the food industry was summarized and analyzed. The performance parameters of the multifunctional cooking experimental platform were determined. Based on the characteristics of each function of the experimental platform, the cooking chamber, furnace door and other components were designed, and the overall plan of the experimental platform was developed. Results: The multi-functional cooking experimental platform developed has four functions: negative pressure, steam, microwave, and baking. It can achieve negative pressure extraction of -28 kPa and direct injection of 390 ℃ superheated steam into the cavity. The heating effect of hot air and microwave is good. Conclusion: The multifunctional cooking experimental platform developed has high feasibility and practicality.

The sub‐pixel terrain long‐wave radiative effect (STLRE) plays an important role in the satellite surface‐sensitive infrared brightness temperature (TB) simulation over rugged areas, however, it is absent in current radiative transfer models. This study incorporates a STLRE scheme in the Community Radiative Transfer Model (CRTM) for the FY‐4A/Advanced Geosynchronous Radiation Imager (AGRI). The total surface downwelling long‐wave radiance (SDLR) over rugged areas at sub‐pixel is composed of the radiance from the overlying atmosphere under plane‐parallel radiation condition and the radiance emitted from surrounding terrains, weighted by the sky view factor (SKV). Based on the homogenous assumption, a STLRE scheme is established through constructing terrain correction factors at AGRI pixel scale. The ExpCTL/ExpTOPO experiments with the CRTM adopting the plane‐parallel scheme/STLRE scheme are conducted to evaluate the simulations of AGRI clear‐sky TB over the rugged areas. Results show that considering the STLRE can significantly reduce the orography dependent simulation biases in the plane‐parallel scheme. The reductions of biases for the AGRI channel 11–13 regionally averaged over the rugged areas are 64.2%, 72.7% and 67.6%, respectively. Stable correction performance is found at different times of the day. Meanwhile, the corrections of SDLR are more obvious in winter than in summer, and in barren condition than in the other land cover types. This is theoretically attributed to the land‐air temperature difference and the land surface emissivity, respectively. This pilot study improves the observation operator for infrared TB data assimilation over complex terrain and exhibits broad promotion and application value. Plain Language Summary: Satellite observations are important for modern numerical weather predictions, but underutilized. Many valuable satellite observations near the surface are not used in numerical models, especially over complex terrain regions. The sub‐pixel terrain long‐wave radiative effect (STLRE) plays an important role in the satellite surface‐sensitive infrared TB simulation over rugged areas, however, it is absent in current radiative transfer models. Consequently, the TB simulation by default CRTM exhibits orography dependent biases over rugged areas. This study focuses on improving the data assimilation ability for infrared observations influenced by complex terrains. We incorporate a STLRE scheme into CRTM and explore the potential benefits for FY‐4A/AGRI TB simulation using the 1‐year TB simulation samples over eastern China during 2022–2023. The new scheme considers the obstruction of atmospheric downwelling radiance by terrain and also the emissive radiance from surrounding terrains. More accurate TB simulations are produced for FY‐4A/AGRI. The results of this study suggest a promising avenue for improving satellite data assimilation over complex terrain in the future. Key Points: Default Community Radiative Transfer Model (CRTM) leads to orography dependent simulation biases for FY‐4A /AGRI over rugged areasA sub‐pixel terrain long‐wave radiative effect parameterization scheme is developed in CRTM for FY‐4A/AGRIConsidering the sub‐pixel terrain long‐wave radiative effect can clearly improve the accuracy of infrared simulation over complex terrain [ABSTRACT FROM AUTHOR]

ERA5 reanalysis data, precipitation data from China, and National Oceanic and Atmospheric Administration (NOAA) monthly sea surface temperature (SST) data are used to analyse the impact of the meridional position of the East Asian subtropical jet (EASJ) on summer precipitation in China and its correlation with Atlantic SST. The results indicate that when the EASJ significantly shifts northward, the western North Pacific subtropical high (WNPSH) weakens with an eastward displacement. Upper‐level convergence and moisture divergence, corresponding to descending motion, lead to decreased precipitation in the Yangtze River Valley (YRV). Meanwhile, upper‐level divergence occurs over South China (SC), the Hexi Corridor (HC), and Northeast China (NEC), where moisture converges and ascends, favouring an increase in precipitation. Conversely, when the EASJ undergoes a significant southward shift, the WNPSH strengthens and expands westward. Opposing atmospheric circulation patterns in these four regions result in reversed precipitation anomalies compared with those observed when the jet shifts northward. The meridional position of the EASJ is closely related to the summer subtropical Atlantic SST. The positive (negative) SST anomaly (SSTA) over the subtropical Atlantic induces negative (positive) geopotential height anomaly in the upper troposphere over the North Atlantic by modulating the atmospheric meridional circulation. Geopotential height anomalies trigger eastward‐propagating Rossby waves, generating anomalous cyclones and anticyclones over East Asia. These anomalous cyclones and anticyclones lead to zonal wind anomalies, which alter the strength of the westerlies on both sides of the climatological jet axis, thereby changing the jet's meridional position. Additionally, the difference in the propagation direction of wave activity flux between positive and negative SSTA alters the distribution of wave energy convergence and divergence in the EASJ region, further affecting the intensity of the average westerly winds on both sides of the climatological jet axis, ultimately producing the changes in the meridional position of the EASJ. [ABSTRACT FROM AUTHOR]

The sea breeze characteristics for 30 years of summer (1981–2010) in the coastal region of Jiangsu Province were analysed in this study, using the four‐step filter method based on ECMWF Fifth‐Generation Reanalysis (ERA5) data. The results showed that the filtering method reasonably identified three types of sea breeze. Additionally, approximately 23% of the total summer days remained; the corkscrew type dominates the three types of sea breeze; and the backdoor sea breeze was the least common. Except for the type of backdoor sea breeze, the other two types had relatively fixed dominant weather types on three coastlines. The synoptic weather patterns in the 500‐hPa level corresponding to each sea breeze type were different. Further, the details of the diurnal cycle of lower tropospheric circulation indicated the strength of the onshore wind and the location of the large potential temperature gradient at noon being influenced by sea breeze type and coastal location. The wind strength for the three types of sea breeze on the middle coastline was stronger than that on the other two coastlines. On the three coastlines, strong onshore winds were concentrated in areas near the coastline, where they reached their maximum strengths around noon. On the southern coastline, strong onshore winds moved further inland. [ABSTRACT FROM AUTHOR]

It's of great significance to study features of raindrop size distribution (DSD) during different stages of the summer monsoon for understanding the precipitation mechanism, which is regarded as credible reference to improve and refine ainfall retrieval algorithms based on satellite and radar observations and the parameterization of microphysics scheme in numerical model. Characteristics of DSD during summer (June to August) of 2015-2017 are investigated using measurements from a ground-based disdrometer in Nanjing. Results show different micro and macro precipitation characteristics among three stages of summer monsoon. Precipitation before Meiyu is characterized by the highest (among the three stages) mean mass-weighted raindrop diameter, average minutely rainfall rate, and intense minutely and strong hourly rainfall occurrences. Despite generally weak convection intensity in this stage, the persistent support from large-scale synoptic conditions, sufficient condensation and the weakened influence from evaporation, breaking-up and entrainment processes are beneficial to produce large raindrops and improve precipitation efficiency. In contrast, precipitation after Meiyu is identified with the greatest frequency of large raindrop and extreme minutely rainfall occurrences. This is mainly caused by severe convective activities under hot and humid atmospheric conditions. Stronger convection is also associated with higher frequency of smaller raindrops. In pace with the northward advancement of the summer monsoon, the convection intensity enhances gradually and breaking-up processes of raindrops heighten as well, which lead to higher ratio of small-raindrop samples with the largest value during the stage after Meiyu. From many aspects of these raindrop and rainfall characteristics, convective precipitation during Meiyu is inferior comparing to that in the other two stages. However, rainfall rates are highest and raindrops are largest during stratiform precipitation due to sufficient coalescence processes under favorable synoptic forcing conditions. The concentration of small raindrops is usually high but the ratio of small raindrops is the lowest in this stage. Among three stages, the binomial relationship between the shape index and slope parameter also differ significantly, depending on the value of the shape index. Compared with Meiyu of 2009-2011, the frequency of intense rainfall occurrence and its contribution to total precipitation decrease while those for weak rainfall increase in terms of both minutely and hourly rainfall. Simultaneously, the binomial relationship of the shape index and slope parameter changes significantly as well.

With the development of refined numerical forecasts, problems such as score distortion due to the division of precipitation thresholds in both traditional and improved scoring methods for precipitation forecasts and the increasing subjective risk arising from the scale setting of the neighborhood spatial verification method have become increasingly prominent. To address these issues, a general comprehensive evaluation method (GCEM) is developed for cross-scale precipitation forecasts by directly analyzing the proximity of precipitation forecasts and observations in this study. In addition to the core indicator of the precipitation accuracy score (PAS), the GCEM system also includes score indices for insufficient precipitation forecasts, excessive precipitation forecasts, precipitation forecast biases, and clear/rainy forecasts. The PAS does not distinguish the magnitude of precipitation and does not delimit the area of influence; it constitutes a fair scoring formula with objective performance and can be suitable for evaluating rainfall events such as general and extreme precipitation. The PAS can be used to calculate the accuracy of numerical models or quantitative precipitation forecasts, enabling the quantitative evaluation of the comprehensive capability of various refined precipitation forecasting products. Based on the GCEM, comparative experiments between the PAS and threat score (TS) are conducted for two typical precipitation weather processes. The results show that relative to the TS, the PAS better aligns with subjective expectations, indicating that the PAS is more reasonable than the TS. In the case of an extreme-precipitation event in Henan, China, two high-resolution models were evaluated using the PAS, TS, and fraction skill score (FSS), verifying the evaluation ability of PAS scoring for predicting extreme-precipitation events. In addition, other indices of the GCEM are utilized to analyze the range and extent of both insufficient and excessive forecasts of precipitation, as well as the precipitation forecasting ability for different weather processes. These indices not only provide overall scores similar to those of the TS for individual cases but also support two-dimensional score distribution plots which can comprehensively reflect the performance and characteristics of precipitation forecasts. Both theoretical and practical applications demonstrate that the GCEM exhibits distinct advantages and potential promotion and application value compared to the various mainstream precipitation forecast verification methods. [ABSTRACT FROM AUTHOR]

The use of remote sensing methods to accurately measure cloud properties and their spatiotemporal changes has been widely welcomed in many fields of atmospheric research. The Nanjing Joint Institute for Atmospheric Sciences (NJIAS) Himawari-8/9 Cloud Feature Dataset (HCFD) provides a comprehensive description of cloud features over the East Asia and west North Pacific regions for the 7-year period from April 2016 to December 2022. Multiple cloud variables, such as cloud mask, phase/type, top height, optical thickness, and particle effective radius, as well as snow, dust, and haze masks, were generated from the visible and infrared measurements of the Advanced Himawari Imager (AHI) on board the Japanese geostationary satellites Himawari-8 and Himawari-9 using a series of recently developed cloud retrieval algorithms. Verifications with the Cloud–Aerosol Lidar with Orthogonal Polarization (CALIOP) 1 km cloud layer product and the Moderate Resolution Imaging Spectroradiometer (MODIS) Level-2 cloud product (MYD06) demonstrate that the NJIAS HCFD gives higher skill scores than the Japanese Himawari-8/9 operational cloud product for all cloud variables except for cloud particle effective radius. The NJIAS HCFD even outperforms the MYD06 in nighttime cloud detection; cloud-top height, pressure, and temperature estimation; and infrared-only cloud-top phase determination. All evaluations are performed at the nominal 2 km scale, not including the effects of sub-pixel cloudiness or very thin cirrus. Two examples are presented to demonstrate applications of the NJIAS HCFD for climate and typhoon research. The NJIAS HCFD has been published in the Science Data Bank (https://doi.org/10.57760/sciencedb.09950 , Zhuge 2023a; https://doi.org/10.57760/sciencedb.09953 , Zhuge 2023b; https://doi.org/10.57760/sciencedb.09954 , Zhuge 2023c; https://doi.org/10.57760/sciencedb.10158 , Zhuge 2023d; https://doi.org/10.57760/sciencedb.09945 , Zhuge 2023e). [ABSTRACT FROM AUTHOR]

With the development of refined numerical forecasts, the problems such as the score distortion due to the division of precipitation thresholds in both traditional and improved scoring methods for precipitation forecast and the increasing subjective risk arisen from the scale setting of the neighbourhood spatial verification method have become increasingly prominent. To solve this issue, a general comprehensive evaluation method (GCEM) has been developed for cross-scale precipitation forecasts by directly analysing the proximity of precipitation forecasts and observations in this study. In addition to the core element of the precipitation forecast accuracy score (PAS) index, the GCEM system also includes score indices for insufficient precipitation forecasts, excessive precipitation forecasts, precipitation forecast biases and clear/rainy forecasts. The PAS does not distinguish the magnitude of precipitation and delimit the area of influence, it constitutes a fair scoring formula with objective performance and can be suitable for evaluating the rainfall events such as general and extreme precipitation. The PAS can be used to calculate the accuracy of numerical models or quantitative precipitation forecasts, enabling the quantitative evaluation of the comprehensive capability of various refined precipitation forecasting products. Based on the GCEM, comparative experiments between the PAS and TS are conducted for two typical precipitation weather processes. The results show that relative to TS, the PAS aligns with subjective expectations much more, indicating that the PAS is more reasonable than the TS. In addition, other indices of the GCEM are utilized to analyse the range and extent of both insufficient and excessive forecasts of precipitation, as well as the precipitation forecast ability in two weather processes. These indices not only provide overall scores for individual cases similar to the TS but also offer two-dimensional score distribution plots, which can comprehensively reflect the performance and characteristics of precipitation forecasts. Both theoretical and practical applications demonstrate that the GCEM exhibits distinct advantages and potential promotion and application value compared to the various mainstream precipitation forecast verification methods. [ABSTRACT FROM AUTHOR]

In this study, a new way to assimilate clear-sky Advanced Himawari Imager (AHI) surface-sensitive brightness temperature (TB) observations over land is investigated for improving quantitative precipitation forecasts (QPFs) in eastern China. To alleviate problems arising from inaccurate surface temperature in radiance simulations, surface station observations of land surface skin temperature (LSST) together with conventional and AMSU-A observations are assimilated to improve AHI surface-sensitive TB simulations of the Community Radiative Transfer Model (CRTM) before AHI data assimilation. First, the Gridpoint Statistical Interpolation (GSI) three-dimensional variational (3DVar) system is updated with the additional control variable of surface temperature and its background error covariances. Second, surface temperature and emissivity sensitivity checks are designed for the quality control of the surface-sensitive AHI channels. Finally, the impacts of a two-time data assimilation strategy are assessed for a local convection rainfall case and a synoptic-scale precipitation case. The experiment in which AHI data are assimilated after assimilating LSST data (ExpL2) outperforms the traditional experiment in which the LSST is not updated (ExpL) in terms of its 24-h QPF skill score. A better description of atmospheric instability and moisture convergence forcing is obtained in ExpL2 than in ExpL. Both experiments show additional low-level temperature and humidity adjustments compared to the experiment that does not assimilate AHI surface-sensitive channels (ExpNL). Lower AHI TB simulation biases are found in the ExpL2 experiment, which improve the analyzed field and subsequent QPFs. The results in this study suggest the importance of proper utilization of LSST observations for AHI surface-sensitive TB assimilations over land. [ABSTRACT FROM AUTHOR]