Shenzhen:A Window on China

When asked if he had confi-dence in the campaign against cor-ruption,the official replied,"Corrup-tion is a persistent ailment.You can wipe it out today,but it'l be back tomorrow.The only way to deal with it is to just keep fighting against it."

Public Participation in Water Environment Control：the Status and Experience of Shenzhen, Southern China

Public participation is an important part of watershed water environment management. Via public participation, it could enhance public environmental awareness, mobilize multiple forces to reconcile the conflicts among multiple interest groups, supervise corporate environmental be-havior, and overcome the shortcomings of government unilateral decision-making. In this paper, the status quo of public participating in water envi-ronment control is summarized, and the existing problems of public participating in water environment control are analyzed. From the aspects of per-fecting legal system, perfecting water environment information disclosure system, expanding information communication channels, correctly guiding the development of environmental social organization, playing the supervision role of the people＇s congress and political consultative committee, and enriching the forms of publicity and education, the countermeasures and suggestions of public participating in water environment control are proposed, to perfect public participation mechanism, and scientifically and orderly impel comprehensive treatment of water environment.

Factors influencing the concentration of negative air ions during the year in forests and urban green spaces of the Dapeng Peninsula in Shenzhen, China

Negative air ions(NAIs)benefit the mental and physical health of humans,but rapid urbanization can decrease the abundance of NAIs.Quantifying the spatial and seasonal distribution of NAIs and determining the factors that infl uence the concentration during urbanization is thus essential.In the present study of a typical developing urban district in southern China,negative air ion concentrations(NAICs)in 60 forests sites and 30 urban green spaces were quantifi ed on seven consecutive days in each of the four seasons.Large seasonal variations in NAIC were revealed in forests and urban green spaces with trough values in summer.NAIC progressively decreased from forests to urban green spaces and was infl uenced by local land morphology,vegetation characteristics,and climatic factors.The vast,heavily vegetated northeastern region was the richest area for NAIs,whereas the narrow central region(urbanized area)was the poorest,implying dramatic impacts of urbanization on the spatial distribution of NAIs.The relationship between air temperature and NAIC was better fi tted with a quadratic equation than a linear equation.Moreover,the NAIC was more sensitive to local morphology in urban green spaces than in urban forests,indicating the vulnerability of NAIs in urbanized areas.Therefore,the appropriate design of local urban morphology is critical.

Leptolaimus holovachovi sp. nov. (Nematoda) from Shenzhen Mangrove Nature Reserve, Shenzhen, South China

A new free-living marine nematode species of the genus Leptolaimus belonging to the family Leptolaimidae was collected from intertidal sediments of the Shenzhen Mangrove Nature Reserve,Shenzhen,South China,and it is described here as Leptolaimus holovachovi sp.nov.The new species is characterized by body length 734-896μm in males and 822-941μm in females;papilliform cephalic sensilla;circular amphideal fovea;males with 7-14 anterior midventral alveoli in the pharyngeal region,4-5 midventral tubular precloacal supplements and 4-6 alveolar precloacal supplements;spicules slender,slightly arcuate,proximally cephalated and distally pointed.Plate-like gubernaculum without apophyses.The new species differs from other congener species of the genus by the unique feature of having anterior midventral alveoli in the pharyngeal region.

The key elements analysis of Guangdong & Shenzhen ETS & tips for China national ETS construction

The only joint effort area of provincial and municipal governments resides in Guangdong Province and Shenzhen City in China's carbon emission trading system(ETS) pilots,which characterize the national carbon ETS plots.The present study on the operating experience from this area has important reference value for the national carbon ETS.Analysis and comparison of the key elements show many differences in coverage,total allowance,allowance allocation,and MRV mechanism between Guangdong and Shenzhen carbon ETS.The present study provides the following explanation:(1)the design characteristics of carbon ETS(e.g.coverage,total quotas,the allocation,and MRV mechanism) depend on the local geographical conditions and policy goals.The differences of economic structure in Guangdong Province and Shenzhen City result in different coverage,which then result in differences in other management elements.(2)The operating state of the carbon market is affected by overall design of carbon ETS:in the case of tighter total allowance,lower proportion of China Certified Emission Reductions,and harsher punishment,the carbon market is relatively active,which intends to produce carbon financial market.Based on deep analysis of operation characteristics of carbon ETS in Guangdong and Shenzhen,the present study suggests that(1)the allowance should be allocated freely at the beginning stage and then gradually transited to the voluntary paid auction;(2)the allowances assigned to companies shall be linked up with their energy-saving objectives;(3)the output fluctuations and economic influence on the allowance allocation should be properly handled to maintain the fairness and consistence of allowance allocation standards;(4)stable public expectation is one of the key elements to maintain the regular operation of carbon ETS;(5)constrained carbon emission behavior outside ETS can contribute to social justice;and(6)the improvement of professional skills of relevant personnel in the enterprise and independent third party can enhance carbon emissions data reliability.

The diffusion of Hong Kong cultural values to China's Mainland: a case study in Shenzhen

s—Since Shenzhen became a special economic zone in 1980, it has achieved spectacular growth in its economy. At the same time, it has opened its door to the importation of foreign goods and cultures,particularly from its neighboring city,Hong Kong.Nowadays,Hong Kong cultural traits, including materialism, individualism, and the idolization of movie stars and pop singers have become well accepted and commonly followed by the people in Shenzhen. This paper looks into the role of mass communication, particularly television programs, in this process of cultural diffusion, and to assess the cause and effect of such changes on Shenzhen.

Using Urban Landscape Trajectories to Assess Fragmentation in Mountainous Coastal Areas: A Case Study of Shenzhen, China

Rapid urbanization in mountainous coastal areas causes dramatic changes in land use and land cover(LUCC)for their geographic location.To understand changes in landscape trajectories in such regions,we examined temporal and spatial changes in urban landscapes in Shenzhen,China,a city that has undergone rapid urbanization in recent decades,and investigated the drivers of landscape pattern evolution at different scales from LUCC data from 1985,1995,2005,and 2015.The results show that the landscape of Shenzhen has changed dramatically over the 30 years from 1985 to 2015.The proportion of forest area decreased from 50.81%to 37.81%,while the proportion of construction land increased from 17.83%to 48.28%.The changes in the landscape patterns in Shenzhen were driven mainly by human activity.This study is one of the first to assess landscape dynamics of the rapid urbanization from the angle of mountainous coastal area,which plays an important role in the land use and city regulation of the global coastal mountains.

Studies on Ecological Monitoring of Plant Community and Plant Diversity in Shenzhen, Southern China

From Jan. 2013 to Nov. 2018, we carried out the investigation on vegetation studies in the ecological monitoring programs, Shenzhen and totally researched 170 plant communities of mountain areas etc., few areas of street regions and parks etc., for communities’ structural characteristics and plant diversity. We comparatively analyzed natural forests, semi-natural forest and artificial forest composition and structural characters and family, genus and species diversity level and the main affected factors. We also researched and analyzed these communities’ structural characteristics and pant diversity, comparatively analyzed natural forests, semi-natural forest and artificial forest composition and structural characters and family, genus and species diversity level, the main affected factors;researched and analyzed the relationship between plant community structure characteristics with the absorbing ability to PM2.5 pollutants. The result showed that the structure and plant diversity of natural forest were obviously better than artificial disturbed forest or artificial forest, the semi-natural forest was the middle level of the forests, In the indices of height, DBH, coverage and crow width etc. of tree layer, natural forests and semi-natural forests were obvious higher than that of artificial disturbed forest or artificial forest;in some forests of artificial disturbed forest or artificial forest, though their richness indices of family and genus were a slightly higher, but this contribution was majorly due to herb layer plants, and some shrub layer plants. Analyzing three kinds of communities, the number of tree layer species of natural forest was the largest, and their every α-diversity index value was the highest;these characteristics values of semi-natural forest were second, artificial disturbed forests or artificial forests were the lowest;in shrub layer, and herb layer, few α-diversity indices of artificial disturbed forest or artificial forest were a slightly higher than that of some natural forests, but the integral values of the diversity indices of natural forest and semi-natural forest were obviously higher than the former. The research showed that in the artificial disturbed forest or artificial forest, because there have some little scale clearing areas, so some pioneer plant species could enter the community and formed a temporarily increase of species diversity, however, these species major were some shrub and herb plants;but tree layer possessed obviously more, even surpassed several ten times biomass than shrub and herb layers. Therefore, the respects of maintain ecosystem stability and other ecological efficient have major and dominated position and so on;and then this community can be natural recovery and succession, those forementioned new entire plants shall withdraw from the community and are replaced by the original plants of the community;but this process has already caused the ecological efficient loss and ecosystem unstable. Above research results are better evidence and theory reference to the argument problems on that are natural forest and natural restoration forest biodiversity higher? or is artificial forest biodiversity higher? and or is more artificial disturbed forest higher? Our researches showed that used random investigation method set quadrats, and combined typical investigation method, the structural indices in the all layer of community and all diversity indices of tree, shrub and herb layers and the integral values were similar, same or usually these indices in the community which set 600 m2, 800 m2 total quatrat area were higher (α-diversity) than that of more than 3000 m2, 4000 m2 or 7000 m2, even more than 17,000 m2 total quadrat area of communities. These lots of researches further proved that according to minimum area method for vegetation survey, in subtropical region, using random investigation method combined with typical investigation set 400 m2 or 400 m2 - 500 m2 total quad

Antarctic Glacial Retreats and the Records of Sea Level Change in Deposits at the North Bank of the Shenzhen Bay,South China

In view of the huge ice cover of 24. 5× 106 km3 in Antarctica, which accounts for over 90 % by volume of the ice body on earth, the movement of Antarctic glaciers is a major control on global sea-level change and climatic fluctuation. As recorded in the Quaternary deposits in King George Island, West Antarctica, three rapid ablations can be recognized at 11000, 9000 and 6100 years ago and the global climate within the past 6000 years is characterized by small-amplitude warm-cold fluctuation. Intertidal deceits at the north bank of the Shenzhen Bay suggest a periodic variation in sea level in about every 670 years over the last 6000 years with low sea levels recorded in the periods of 5500 - 4900, 3900 - 3600, 2400 2200 and 1300 - 1200 years ago. Between these periods the sea level rised for about 80 cm onaverage. The modern warming climate in the last century corresponds with a rise of sea level atthe rate of 2 - 3 mm/a.

The impact of Internet access on household dietary quality:Evidence from rural China

Over the past few decades,the Internet has rapidly diffused across China.The spread of the Internet has had a profound economic and social impact on Chinese rural areas.Existing research shows that Internet access significantly impacts agricultural production and improves smallholder farmers’income.Beyond these,the Internet can affect other dimensions of social welfare.However,research about the impact of Internet access on dietary quality in rural China remains scarce.This study utilizes multi-period panel data from Fixed Observation Point in rural China from 2009 to 2015 to estimate the impact of Internet access on dietary quality and food consumption of rural households and conducts a causal analysis.Regression models with time and household fixed effects allow robust estimation while reducing potential issues of unobserved heterogeneity.The estimates show that Internet access has significantly increased rural household dietary quality(measured by the Chinese Diet Balance Index).Further research finds that Internet access has increased the consumption of animal products,such as aquatic and dairy products.We also examine the underlying mechanisms.Internet access improves dietary quality and food consumption mainly through increasing household income and food expenditure.These results encourage the promotion of Internet access as a valuable tool for nutritional improvements,especially in rural areas.

Differences in spring precipitation over southern China associated with multiyear La Ni?a events

Composite analyses were performed in this study to reveal the difference in spring precipitation over southern China during multiyear La Ni?a events during 1901 to 2015. It was found that there is significantly below-normal precipitation during the first boreal spring, but above-normal precipitation during the second year. The difference in spring precipitation over southern China is correlative to the variation in western North Pacific anomalous cyclone(WNPC), which can in turn be attributed to the different sea surface temperature anomaly(SSTA) over the Tropical Pacific. The remote forcing of negative SSTA in the equatorial central and eastern Pacific and the local air-sea interaction in the western North Pacific are the usual causes of WNPC formation and maintenance.SSTA in the first spring is stronger than those in the second spring. As a result, the intensity of WNPC in the first year is stronger, which is more likely to reduce the moisture in southern China by changing the moisture transport, leading to prolonged precipitation deficits over southern China. However, the tropical SSTA signals in the second year are too weak to induce the formation and maintenance of WNPC and the below-normal precipitation over southern China. Thus, the variation in tropical SSTA signals between two consecutive springs during multiyear La Ni?a events leads to obvious differences in the spatial pattern of precipitation anomaly in southern China by causing the different WNPC response.

The Origin of Mesozoic A-type Granitoids,Fujian Province,Southeast China:Insights from Geochronology,Mineralogy and Geochemistry

The magma sources,origins and precise forming ages of the miarolite from Qishan and Kuiqi intrusions are still uncertain.New results reveal that,miarolites from the Qishan and Kuiqi intrusions yield crystallization ages of~101 and~98 Ma,and they have a high formation temperature(~910℃)and low oxygen fugacity value,indicating crystallization condition at low pressure in the upper crust with temperature of 678℃.The Qishan and Kuiqi miarolites are characterized by enrichment in SiO_(2) and high-K alkali,depletion in Ca and Mg,and belong to the high-K weak peraluminous rock series.The samples are enriched in HFSEs(i.e.,Ta,Zr and Hf)and LILEs(i.e.,Ba,P and Sr),depleted in Ba and Sr with the negative anomaly of Eu.In the primitive mantle normalized trace element spider diagram,the samples show a right-inclined‘seagull-type’pattern,combined the ratios of(La/Yb)_(N),10000×Al/Ga,Rb/Nb and Nb/Ta etc.,they were proved to be alkaline A-type granite.Combined the characterize of the trace elements,they were derived from clay-rich source accompanied pelite melting,and subjected to K-feldspar crystallization fractional.The values of ε_(Hf)(t)and tDM2 are distributed in the range of-2.8 to 3.3 with~1.2 Ga,and-6.0 to 4.0 with~1.2 Ga,revealing that they were generated from the Mesoproterozoic Cathaysia basement rocks.The comprehensive research reveals the Kuiqi and Qishan intrusions derived from crust-mantle mixing and partial melting of the crust,respectively,resulting from lithospheric extension generated by the Paleo-Pacific Plate subducted into the European-Asian Plate.

Trace elements in magmatic and hydrothermal quartz:Implications on the genesis of the Xingluokeng Tungsten Deposit,South China

The Xingluokeng deposit is the largest gran-ite-related tungsten deposit within the Wuyi metallogenic belt in South China.The Xingluokeng intrusion primarily consists of porphyritic biotite granite,biotite granite,andfine-grained granite.The deposit is represented by veinlet-disseminated mineralization with K-feldspathization and biotitization,alongside quartz-vein mineralization with gre-isenization and sericitization.This study investigates in-situ analyses of quartz compositions from both the intrusion and hydrothermal veinlets and veins.Trace element correlations indicate that trivalent Al^(3+)and Fe^(3+)replace Si^(4+)within the quartz lattice,with monovalent cations(such as Li^(+),Na^(+),and K^(+))primarily serving as charge compensators.Low Ge/Al ratios(<0.013)of quartz from granites suggest a mag-matic origin.The low Al/Ti and Ge/Ti ratios,accompanied by high Ti contents in quartz,suggest that the porphyritic biotite granite and biotite granite are characterized by rela-tively low levels of differentiation and high crystallization temperatures.In contrast,thefine-grained granite exhibits a higher degree of fractionation,lower crystallization tem-peratures,and a closer association with tungsten miner-alization.Ti contents in quartz from quartz veins indicate Qz-Ⅰformed at temperatures above 400°C,while Qz-Ⅱto Qz-Ⅴformed at temperatures below 350°C.Variations in different generations of quartz,as indicated by Al content and(Al+Fe)/(Li+Na+K)ratio,suggest that Qz-Ⅰprecipi-tated from a less acidicfluid with a stable pH,whereas Qz-Ⅱto Qz-Ⅴoriginated from a more acidicfluid with notable pH variations.Consequently,alkaline alteration and acidic alteration supplied the essential Ca and Fe for the precipita-tion of scheelite and wolframite,respectively,highlighting a critical mechanism in tungsten mineralization at the Xin-gluokeng deposit.

Synergistic Interdecadal Evolution of Precipitation over Eastern China and the Pacific Decadal Oscillation during 1951-2015

By using the multi-taper method(MTM)of singular value decomposition(SVD),this study investigates the interdecadal evolution(10-to 30-year cycle)of precipitation over eastern China from 1951 to 2015 and its relationship with the North Pacific sea surface temperature(SST).Two significant interdecadal signals,one with an 11-year cycle and the other with a 23-year cycle,are identified in both the precipitation and SST fields.Results show that the North Pacific SST forcing modulates the precipitation distribution over China through the effects of the Pacific Decadal Oscillation(PDO)-related anomalous Aleutian low on the western Pacific subtropical high(WPSH)and Mongolia high(MH).During the development stage of the PDO cold phase associated with the 11-year cycle,a weakened WPSH and MH increased the precipitation over the Yangtze River Basin,whereas an intensified WPSH and MH caused the enhanced rain band to move northward to North China during the decay stage.During the development stage of the PDO cold phase associated with the 23-year cycle,a weakened WPSH and MH increased the precipitation over North China,whereas an intensified WPSH and the weakened MH increased the precipitation over South China during the decay stage.The 11-year and 23-year variabilities contribute differently to the precipitation variations in the different regions of China,as seen in the 1998flooding case.The 11-year cycle mainly accounts for precipitation increases over the Yangtze River Basin,while the 23-year cycle is responsible for the precipitation increase over Northeast China.These results have important implications for understanding how the PDO modulates the precipitation distribution over China,helping to improve interdecadal climate prediction.

Spatial patterns of zooplankton abundance,biovolume,and size structure in response to environmental variables:a case study in the Yellow Sea and East China Sea

The Yellow Sea(YS)and East China Sea(ECS)are highly dynamic marginal seas of the northwestern Pacific Ocean.To gain an in-depth understanding of zooplankton community structure,zooplankton abundance,biovolume,and size structure in summer 2017 in the YS and ECS were assessed using ZooScan imaging analysis.Zooplankton abundance and biovolume ranged 2.94–1187.14 inds./m^(3)and 3.13–3438.51 mm^(3)/m^(3),respectively.Based on the biovolume data of the categorized size classes of 26 identified taxonomic groups,the zooplankton community was classified into five groups,and each group was coupled with distinctive oceanographic features.Under the influence of the Yellow Sea Cold Water Mass,the Yellow Sea offshore group featured the lowest bottom temperature(10.84±3.42℃)and the most abundant Calanoids(mainly in the 2–3 mm size class).In the Yellow Sea inshore group,Hydrozoans showed the largest biovolume and dominated in the 3–4-mm and>5-mm size classes.The East China Sea offshore group,which was affected by the Kuroshio Branch Current,featured high temperature and salinity,and the lowest bottom dissolved oxygen(2.58±0.5 mg/L).The lowest values of zooplankton abundance and biovolume in the East China Sea offshore group might be attributed to the bottom dissolved oxygen contents.The East China Sea inshore group,which was mainly influenced by the Zhejiang-Fujian Coastal Current and Changjiang Diluted Water,was characterized by high chlorophyll a and the largest biovolume of carnivorous Siphonophores(280.82±303.37 mm^(3)/m^(3)).The Changjiang River estuary offshore group showed the most abundant Cyclopoids,which might be associated with the less turbid water mass in this region.Seawater temperature was considered the most important factor in shaping the size compositions of Calanoids in different groups.

Climate and topography regulate the spatial pattern of soil salinization and its effects on shrub community structure in Northwest China

Soil salinization may affect biodiversity and species composition,leading to changes in the plant community structure.However,few studies have explored the spatial pattern of soil salinization and its effects on shrub community structure at the ecosystem scale.Therefore,we conducted a transect sampling of desert shrublands in Northwest China during the growing season(June–September)in 2021.Soil salinization(both the degree and type),shrub community structure(e.g.,shrub density and height),and biodiversity parameters(e.g.,Simpson diversity,Margalf abundance,Shannon-Wiener diversity,and Pielou evenness indices)were used to assess the effects of soil salinization on shrub community structure.The results showed that the primary degree of soil salinization in the study area was light salinization,with the area proportion of 69.8%.Whereas the main type of soil salinization was characterized as sulfate saline soil,also accounting for 69.8%of the total area.Notably,there was a significant reduction in the degree of soil salinization and a shift in the type of soil salinization from chloride saline soil to sulfate saline soil,with an increase in longitude.Regional mean annual precipitation(MAP),mean annual evapotranspiration(MAE),elevation,and slope significantly contributed to soil salinization and its geochemical differentiation.As soil salinization intensified,shrub community structure displayed increased diversity and evenness,as indicated by the increases in the Simpson diversity,Shannon-Wiener diversity,and Pielou evenness indices.Moreover,the succulent stems and leaves of Chenopodiaceae and Tamaricaceae exhibited clear advantages under these conditions.Furthermore,regional climate and topography,such as MAP,MAE,and elevation,had greater effects on the distribution of shrub plants than soil salinization.These results provide a reference for the origin and pattern of soil salinization in drylands and their effects on the community structure of halophyte shrub species.

Paleogene transgression process and environmental evolution in the deepwater area of the Baiyun Depression in the northern South China Sea

Multiple borehole samples are collected from the Baiyun Depression in deep-water area of the northern South China Sea(SCS)in an effort to reconstruct transgression processes during the Paleogene based on palynalgal analysis.This study indicates that the Baiyun Depression generated a large group of palynopore assemblages and fluvial/lacustrine-related algae during the early and middle Eocene when the Wenchang Formation was deposited.The entire depression was dominated by fluvial and lacustrine facies before transgression.Its eastern and southeastern sags transitioned to shallow marine environment by generating a large abundance of marine dinoflagellates during the Enping deposition of the late Eocene.Meanwhile,the southern uplift zone simply yielded fluvial/lacustrine-related palynopores and algae,and was dominated by the fluvial and lacustrine environment during the early stage of the Enping Formation,prior to shifting into transitional setting in the later period.Northwestern sags remained extensive fluvial and delta facies without existence of marine dinoflagellates.It was until the depositional stage of the Zhuhai Formation(Oligocene)that the overall depression was strongly impacted from transgression process.Both eastern and southeastern sags were mainly under deep marine setting on a continental slope while northwestern and southern areas developed transitional facies.Although distribution and accumulation patterns varied greatly among sub-sags,the overall Baiyun Depression was characterized by widespread development of marine dinoflagellates.It should be noted that the northwestern sag also partly generated large-scale river delta deposits.Due to the eustatic rise and change of SCS spreading axis,the overall Baiyun Depression was mostly influenced by the deep marine environment on a continental slope during the early Miocene.Both northwestern sag and southern uplift zone were found plentiful marine dinoflagellates.In summary,transgression initiated from the eastern and southeastern Baiyun Depression before subsequently progressing into the farther west.Evolution of transgression process is also greatly consistent with the gradual westward expansion of the SCS.

Different ENSO Impacts on Eastern China Precipitation Patterns in Early and Late Winter Associated with Seasonally-Varying Kuroshio Anticyclonic Anomalies

Winter precipitation over eastern China displays remarkable interannual variability,which has been suggested to be closely related to El Niño-Southern Oscillation(ENSO).This study finds that ENSO impacts on eastern China precipitation patterns exhibit obvious differences in early(November-December)and late(January-February)winter.In early winter,precipitation anomalies associated with ENSO are characterized by a monopole spatial distribution over eastern China.In contrast,the precipitation anomaly pattern in late winter remarkably changes,manifesting as a dipole spatial distribution.The noteworthy change in precipitation responses from early to late winter can be largely attributed to the seasonally varying Kuroshio anticyclonic anomalies.During the early winter of El Niño years,anticyclonic circulation anomalies appear both over the Philippine Sea and Kuroshio region,enhancing water vapor transport to the entirety of eastern China,thus contributing to more precipitation there.During the late winter of El Niño years,the anticyclone over the Philippine Sea is further strengthened,while the one over the Kuroshio dissipates,which could result in differing water vapor transport between northern and southern parts of eastern China and thus a dipole precipitation distribution.Roughly the opposite anomalies of circulation and precipitation are displayed during La Niña winters.Further analysis suggests that the seasonally-varying Kuroshio anticyclonic anomalies are possibly related to the enhancement of ENSO-related tropical central-eastern Pacific convection from early to late winter.These results have important implications for the seasonal-tointerannual predictability of winter precipitation over eastern China.

Spatio-Temporal Characteristics of Heavy Precipitation Forecasts from ECMWF in Eastern China

This study examines the spatio-temporal characteristics of heavy precipitation forecasts in eastern China from the European Centre for Medium-Range Weather Forecasts(ECMWF) using the time-domain version of the Method for Object-based Diagnostic Evaluation(MODE-TD). A total of 23 heavy rainfall cases occurring between 2018 and 2021 are selected for analysis. Using Typhoon “Rumbia” as a case study, the paper illustrates how the MODE-TD method assesses the overall simulation capability of models for the life history of precipitation systems. The results of multiple tests with different parameter configurations reveal that the model underestimates the number of objects’ forecasted precipitation tracks, particularly at smaller radii. Additionally, the analysis based on centroid offset and area ratio tests for different classified precipitation objects indicates that the model performs better in predicting large-area, fast-moving, and longlifespan precipitation objects. Conversely, it tends to have less accurate predictions for small-area, slow-moving, and shortlifespan precipitation objects. In terms of temporal characteristics, the model overestimates the forecasted movement speed for precipitation objects with small-area, slow movement, or both long and short lifespans while underestimating it for precipitation with fast movement. In terms of temporal characteristics, the model tends to overestimate the forecasted movement speed for precipitation objects with small-area, slow movement, or both long and short lifespans while underestimating it for precipitation with fast movement. Overall, the model provides more accurate predictions for the duration and dissipation of precipitation objects with large-area or long-lifespan(such as typhoon precipitation) while having large prediction errors for precipitation objects with small-area or short-lifespan. Furthermore, the model’s simulation results regarding the generation of precipitation objects show that it performs relatively well in simulating the generation of large-area and fast-moving precipitation objects. However, there are significant differences in the forecasted generation of small-area and slow-moving precipitation objects after 9 hours.

Assessment of International GNSS Service Global Ionosphere Map products over China region based on measurements from the Crustal Movement Observation Network of China

The global ionosphere maps(GIM)provided by the International GNSS Service(IGS)are extensively utilized for ionospheric morphology monitoring,scientific research,and practical application.Assessing the credibility of GIM products in data-sparse regions is of paramount importance.In this study,measurements from the Crustal Movement Observation Network of China(CMONOC)are leveraged to evaluate the suitability of IGS-GIM products over China region in 2013-2014.The indices of mean error(ME),root mean square error(RMSE),and normalized RMSE(NRMSE)are then utilized to quantify the accuracy of IGS-GIM products.Results revealed distinct local time and latitudinal dependencies in IGS-GIM errors,with substantially high errors at nighttime(NRMSE:39%)and above 40°latitude(NRMSE:49%).Seasonal differences also emerged,with larger equinoctial deviations(NRMSE:33.5%)compared with summer(20%).A preliminary analysis implied that the irregular assimilation of sparse IGS observations,compounded by China’s distinct geomagnetic topology,may manifest as error variations.These results suggest that modeling based solely on IGS-GIM observations engenders inadequate representations across China and that a thorough examination would proffer the necessary foundation for advancing regional total electron content(TEC)constructions.