The development course of China's meteorological movie and television was analyzed firstly, and then the improvement strategies of meteorological movie and television services facing public needs were put forward bas...The development course of China's meteorological movie and television was analyzed firstly, and then the improvement strategies of meteorological movie and television services facing public needs were put forward based on the statistical results of a meteorological service questionnaire.展开更多
An ensemble optimal interpolation(EnOI)data assimilation method is applied in the BCCCSM1.1 to investigate the impact of ocean data assimilations on seasonal forecasts in an idealized twin experiment framework.Pseudoo...An ensemble optimal interpolation(EnOI)data assimilation method is applied in the BCCCSM1.1 to investigate the impact of ocean data assimilations on seasonal forecasts in an idealized twin experiment framework.Pseudoobservations of sea surface temperature(SST),sea surface height(SSH),sea surface salinity(SSS),temperature and salinity(T/S)profiles were first generated in a free model run.Then,a series of sensitivity tests initialized with predefined bias were conducted for a one-year period;this involved a free run(CTR)and seven assimilation runs.These tests allowed us to check the analysis field accuracy against the"truth".As expected,data assimilation improved all investigated quantities;the joint assimilation of all variables gave more improved results than assimilating them separately.One-year predictions initialized from the seven runs and CTR were then conducted and compared.The forecasts initialized from joint assimilation of surface data produced comparable SST root mean square errors to that from assimilation of T/S profiles,but the assimilation of T/S profiles is crucial to reduce subsurface deficiencies.The ocean surface currents in the tropics were better predicted when initial conditions produced by assimilating T/S profiles,while surface data assimilation became more important at higher latitudes,particularly near the western boundary currents.The predictions of ocean heat content and mixed layer depth are significantly improved initialized from the joint assimilation of all the variables.Finally,a central Pacific El Ni?o was well predicted from the joint assimilation of surface data,indicating the importance of joint assimilation of SST,SSH,and SSS for ENSO predictions.展开更多
Socialization of meteorological services is important guarantee of servicing national major development strategy,strategic selection of adapting to national reform,urgent need of meeting the development of related ind...Socialization of meteorological services is important guarantee of servicing national major development strategy,strategic selection of adapting to national reform,urgent need of meeting the development of related industries,and necessary way of solving public demand on meticulous,targeted and personalized meteorological services. At present,socialization construction of meteorological services in China still has many problems,such as weak service capability of intelligent weather,inadequate and imbalanced urban-rural and regional development,insufficient sharing and opening of meteorological data,and deficient role of social organization. It should vigorously impel socialization of meteorological services by exploring sharing and opening mechanism of basic meteorological data,establishing policy,regulation and standard system adapting to socialization of meteorological services,establishing operation mechanism for socialization of meteorological services of government dominance combining market,enriching content and means of meteorological socialization service.展开更多
In the conflict dialogue between tradition and modernity,Gaomi City practices the theory of creative transformation and innovative development and explores cultural and tourism integration by combining folk customs an...In the conflict dialogue between tradition and modernity,Gaomi City practices the theory of creative transformation and innovative development and explores cultural and tourism integration by combining folk customs and tourism in practices and application scenarios.展开更多
The Tibet Plateau is one of the regions with the richest solar energy resources in the world.In the process of achieving carbon neutrality in China,the development and utilization of solar energy resources in the regi...The Tibet Plateau is one of the regions with the richest solar energy resources in the world.In the process of achieving carbon neutrality in China,the development and utilization of solar energy resources in the region will play an important role.In this study,the gridded solar resource data with 1km resolution in Tibet were obtained by spatial correction and downscaling of SMARTS model.On this basis,the spatial and temporal distribution characteristics of solar energy resources in the region in the past 30 years(1991–2020)are finely evaluated,and the annual global horizontal radiation resource is calculated.The results show that:1)The average annual global horizontal radiation amount in Tibet is 1816 kWh/m^(2).More than 60%of the area belongs to the“Most abundant”(GHI≥1750 kWh/m^(2))area of China’s solar energy resources category A,and nearly 40%belongs to the“Quite abundant”(1400≤GHI<1750)area of China’s solar energy resource category B.2)In space,the solar energy resources in Tibet increased gradually from north to south and from east to west.Lhasa,Central and Eastern Shigatse,Shannan,and Southwestern Ali are the most abundant cities,with a maximum annual radiation level of 2189 kWh/m2.3)In terms of time,the total horizontal radiation in Tibet was the highest in May and the lowest in December.74%of the total area belongs to the“Very stable”(R_(w)≥0.47)area of solar resource stability category A,and 26%belongs to the“stable”(0.36≤R_(w)<0.47)area of solar resource stability category B.Solar energy resources in the region show the characteristics of both strong and stable.Average solar energy resources in the region have shown a fluctuating downward trend over the past 30 years,with an average decline of about 12.86(kWh/m2)per decade.4)In terms of solar radiation resources reaching the earth’s surface,the theoretical total amount of annual horizontal radiation in Tibet is about 240.07 billion tons of standard coal or 222.91 billion kilowatts on average.展开更多
In the present study,multimodel ensemble forecast experiments of the global horizontal irradiance(GHI)were conducted using the dynamic variable weight technique.The study was based on the forecasts of four numerical m...In the present study,multimodel ensemble forecast experiments of the global horizontal irradiance(GHI)were conducted using the dynamic variable weight technique.The study was based on the forecasts of four numerical models,namely,the China Meteorological Administration Wind Energy and Solar Energy Prediction System,the Mesoscale Weather Numerical Prediction System of China Meteorological Administration,the China Meteorological Administration Regional Mesoscale Numerical Prediction System-Guangdong,and the Weather Research and Forecasting Model-Solar,and observational data from four photovoltaic(PV)power stations in Yangjiang City,Guangdong Province.The results show that compared with those of the monthly optimal numerical model forecasts,the dynamic variable weight-based ensemble forecasts exhibited 0.97%-15.96%smaller values of the mean absolute error and 3.31%-18.40%lower values of the root mean square error(RMSE).However,the increase in the correlation coefficient was not obvious.Specifically,the multimodel ensemble mainly improved the performance of GHI forecasts below 700 W m^(-2),particularly below 400 W m^(-2),with RMSE reductions as high as 7.56%-28.28%.In contrast,the RMSE increased at GHI levels above 700 W m^(-2).As for the key period of PV power station output(02:00-07:00),the accuracy of GHI forecasts could be improved by the multimodel ensemble:the multimodel ensemble could effectively decrease the daily maximum absolute error(AE max)of GHI forecasts.Moreover,with increasing forecasting difficulty under cloudy conditions,the multimodel ensemble,which yields data closer to the actual observations,could simulate GHI fluctuations more accurately.展开更多
Since ancient times,calligraphy and meteorology have had an inseparable relationship.Wang Xizhi s Prologue to the Collection of Poems Composed at the Orchid Pavilion records the beautiful scenery of mild wind and brig...Since ancient times,calligraphy and meteorology have had an inseparable relationship.Wang Xizhi s Prologue to the Collection of Poems Composed at the Orchid Pavilion records the beautiful scenery of mild wind and bright sun,as well as the relaxed and joyful mood of people in such weather.Su Shi s Cold Food Calligraphy Copybook records the scenery of solar terms and the author s psychological changes during these solar terms through calligraphy.The Quick Snow and Clear Time Calligraphy Copybook also reflects the grandeur of snowy days and the customs of literati recording weather and sharing it with friends.In Sun Guoting s Shupu,it is clearly stated that the third element of the"five harmony and five obedience"refers to the clear sky,humid air,and pleasant climate,and excellent climatic conditions are conducive to writing.展开更多
BACKGROUND Aberrant methylation is common during the initiation and progression of colorectal cancer(CRC),and detecting these changes that occur during early adenoma(ADE)formation and CRC progression has clinical valu...BACKGROUND Aberrant methylation is common during the initiation and progression of colorectal cancer(CRC),and detecting these changes that occur during early adenoma(ADE)formation and CRC progression has clinical value.AIM To identify potential DNA methylation markers specific to ADE and CRC.METHODS Here,we performed SeqCap targeted bisulfite sequencing and RNA-seq analysis of colorectal ADE and CRC samples to profile the epigenomic-transcriptomic landscape.RESULTS Comparing 22 CRC and 25 ADE samples,global methylation was higher in the former,but both showed similar methylation patterns regarding differentially methylated gene positions,chromatin signatures,and repeated elements.High-grade CRC tended to exhibit elevated methylation levels in gene promoter regions compared to those in low-grade CRC.Combined with RNA-seq gene expression data,we identified 14 methylation-regulated differentially expressed genes,of which only AGTR1 and NECAB1 methylation had prognostic significance.CONCLUSION Our results suggest that genome-wide alterations in DNA methylation occur during the early stages of CRC and demonstrate the methylation signatures associated with colorectal ADEs and CRC,suggesting prognostic biomarkers for CRC.展开更多
Cracking during construction is a common occurrence in modern bridge engineering that can directly impact the overall safety of the bridge.Therefore,it is essential to focus on preventing and controlling cracks.As the...Cracking during construction is a common occurrence in modern bridge engineering that can directly impact the overall safety of the bridge.Therefore,it is essential to focus on preventing and controlling cracks.As the construction technology for bridge engineering has evolved,the internal quality of construction has significantly improved.However,the appearance quality remains a crucial factor that reflects the technical expertise of a construction company.Therefore,minimizing cracks and improving the appearance quality of concrete are critical issues that require the attention of construction units,supervision departments,and construction companies.This article will analyze the causes of cracking and suggest corresponding prevention and treatment methods.展开更多
With consecutive occurrences of drought disasters in China in recent years, it is important to estimate their potential impacts on regional crop production. In this study, we detect the impacts of drought on wheat and...With consecutive occurrences of drought disasters in China in recent years, it is important to estimate their potential impacts on regional crop production. In this study, we detect the impacts of drought on wheat and maize yield and their changes at a 0.5&#176;&#215;0.5&#176; grid scale in the wheat-maize rotation planting area in the North China Plain under the A1B climate change scenario using the Decision Support System for Agrotechnology Transfer (DSSAT) model and the outputs of the regional climate modeling system-Providing Regional Climates for Impacts Studies (PRECIS). Self-calibrating palmer drought severity index was used as drought recognition indicator. Two time slices used for the study were the baseline (1961-1990) and 40 years of 2011-2050. The results indicate that the potential planting region for double crop system of wheat-maize would expend northward. The statistic conclusions of crop simulations varied considerably between wheat and maize. In disaster-affected seasons, wheat yield would increase in the future compared with baseline yields, whereas in opposite for maize yield. Potential crop yield reductions caused by drought would be lower for wheat and higher for maize, with a similar trend found for the ratio of potential crop yield reductions for both crops. It appears that the negative impact of drought on maize was larger than that on wheat under climate change A1B scenario.展开更多
Leveraging the commercial CFD software FLUENT,the fine-scale three-dimensional wind structure over the Paiya Mountains on the Dapeng Peninsula near Shenzhen,a city on the seashore of South China Sea,during the landfal...Leveraging the commercial CFD software FLUENT,the fine-scale three-dimensional wind structure over the Paiya Mountains on the Dapeng Peninsula near Shenzhen,a city on the seashore of South China Sea,during the landfall of Typhoon Molave has been simulated and analyzed.Through the study,a conceptual wind structure model for mountainous areas under strong wind condition is established and the following conclusions are obtained as follows:(1)FLUENT can reasonably simulate a three-dimensional wind structure over mountainous areas under strong wind conditions;(2)the kinetic effect of a mountain can intensify wind speed in the windward side of the mountain and the area over the mountain peak;and(3)in the leeward side of the mountain,wind speed is relatively lower with relatively stronger wind shear and turbulence.展开更多
A real-time channel flood forecast model was developed to simulate channel flow in plain rivers based on the dynamic wave theory. Taking into consideration channel shape differences along the channel, a roughness upda...A real-time channel flood forecast model was developed to simulate channel flow in plain rivers based on the dynamic wave theory. Taking into consideration channel shape differences along the channel, a roughness updating technique was developed using the Kalman filter method to update Manning's roughness coefficient at each time step of the calculation processes. Channel shapes were simplified as rectangles, triangles, and parabolas, and the relationships between hydraulic radius and water depth were developed for plain rivers. Based on the relationship between the Froude number and the inertia terms of the momentum equation in the Saint-Venant equations, the relationship between Manning's roughness coefficient and water depth was obtained. Using the channel of the Huaihe River from Wangjiaba to Lutaizi stations as a case, to test the performance and rationality of the present flood routing model, the original hydraulic model was compared with the developed model. Results show that the stage hydrographs calculated by the developed flood routing model with the updated Manning's roughness coefficient have a good agreement with the observed stage hydrographs. This model performs better than the original hydraulic model.展开更多
BACKGROUND Interdigestive migrating motor complexes(MMC)produce periodic contractions in the gastrointestinal tract,but the exact mechanism of action still remains unclear.Intramuscular interstitial cells of Cajal(ICC...BACKGROUND Interdigestive migrating motor complexes(MMC)produce periodic contractions in the gastrointestinal tract,but the exact mechanism of action still remains unclear.Intramuscular interstitial cells of Cajal(ICC-IM)participate in gastrointestinal hormone and neuromodulation,but the correlation between ICCIM and MMC is also unclear.We found that xiangbinfang granules(XBF)mediated the phase III contraction of MMC.Here,the effects of XBF on gastric antrum motility in W/Wv mice and the effects of ICC-IM on gastric antrum MMC are reported.AIM To observe the effects of ICC-IM on gastric antrum motility and to establish the mechanism of XBF in promoting gastric antrum motility.METHODS The density of c-kit-positive ICC myenteric plexus(ICC-MP)and ICC-IM in the antral muscularis of W/Wv and wild-type(WT)mice was examined by confocal microscopy.The effects of XBF on gastric antrum slow waves in W/Wv and WT mice were recorded by intracellular amplification recording.Micro-strain-gauge force transducers were implanted into the gastric antrum to monitor the MMC and the effect of XBF on gastric antrum motility in conscious W/Wv and WT mice.RESULTS In the gastric antrum of W/Wv mice,c-kit immunoreactivity was significantly reduced,and no ICC-IM network was observed.Spontaneous rhythmic slow waves also appeared in the antrum of W/Wv mice,but the amplitude of the antrum slow wave decreased significantly in W/Wv mice(22.62±2.23 mV vs 2.92±0.52 mV,P<0.0001).MMCs were found in 7 of the 8 WT mice but no complete MMC cycle was found in W/Wv mice.The contractile frequency and amplitude index of the gastric antrum were significantly increased in conscious WT compared to W/Wv mice(frequency,3.53±0.18 cpm vs 1.28±0.12 cpm;amplitude index,23014.26±1798.65 mV·20 min vs 3782.16±407.13 mV·20 min;P<0.0001).XBF depolarized smooth muscle cells of the gastric antrum in WT and W/Wv mice in a dose-dependent manner.Similarly,the gastric antrum motility in WT mice was significantly increased after treatment with XBF 5 mg(P<0.05).Atropine(0.1 mg/kg)blocked the enhancement of XBF in WT and W/Wv mice completely,while tetrodotoxin(0.05 mg/kg)partially inhibited the enhancement by XBF.CONCLUSION ICC-IM participates in the regulation of gastric antrum MMC in mice.XBF induces MMC III-like contractions that enhance gastric antrum motility via ICCIM in mice.展开更多
In this paper,new situation faced by meteorological science popularization work of China is analyzed. Based on analyzing the challenges faced by Hubei meteorological science popularization work,the suggestions of Hube...In this paper,new situation faced by meteorological science popularization work of China is analyzed. Based on analyzing the challenges faced by Hubei meteorological science popularization work,the suggestions of Hubei meteorological science popularization work during the " 13 th five-year" period are proposed from four aspects: further optimize operation mechanism of meteorological science popularization work,and improve work efficiency; combine full-time and part-time teams,and promote the fighting capacity of the science popularization team; adapt to the demand of multimedia publicity,and expand the connotation of popular science creation; build brand,and create a stereoscopic science popularization network.展开更多
Assimilation of the Advanced Geostationary Radiance Imager(AGRI)clear-sky radiance in a regional model is performed.The forecasting effectiveness of the assimilation of two water vapor(WV)channels with conventional ob...Assimilation of the Advanced Geostationary Radiance Imager(AGRI)clear-sky radiance in a regional model is performed.The forecasting effectiveness of the assimilation of two water vapor(WV)channels with conventional observations for the“21·7”Henan extremely heavy rainfall is analyzed and compared with a baseline test that assimilates only conventional observations in this study.The results show that the 24-h cumulative precipitation forecast by the assimilation experiment with the addition of the AGRI exceeds 500 mm,compared to a maximum value of 532.6 mm measured by the national meteorological stations,and that the location of the maximum precipitation is consistent with the observations.The results for the short periods of intense precipitation processes are that the simulation of the location and intensity of the 3-h cumulative precipitation is also relatively accurate.The analysis increment shows that the main difference between the two sets of assimilation experiments is over the ocean due to the additional ocean observations provided by FY-4A,which compensates for the lack of ocean observations.The assimilation of satellite data adjusts the vertical and horizontal wind fields over the ocean by adjusting the atmospheric temperature and humidity,which ultimately results in a narrower and stronger WV transport path to the center of heavy precipitation in Zhengzhou in the lower troposphere.Conversely,the WV convergence and upward motion in the control experiment are more dispersed;therefore,the precipitation centers are also correspondingly more dispersed.展开更多
Due to the existence of thermal offsets,global solar irradiances measured by pyranometers are smaller than actual values,and errors are larger in the daytime.Until now,there is no universally-recognized correction met...Due to the existence of thermal offsets,global solar irradiances measured by pyranometers are smaller than actual values,and errors are larger in the daytime.Until now,there is no universally-recognized correction method for thermal offset errors.Therefore,it is imperative to identify a convenient and effective correction method.Five correction methods were evaluated based on the data measured from a field experiment from 23 January to 15 November,2011.Results have shown:1) Temporal variation characteristics of thermal offsets in the four tested pyranometers are consistent.2) Among the five methods,non-dimensional quantity method is suggested for use to correct thermal offsets,because it is convenient and no modification of instruments is required.If collocated net longwave radiation and wind speed data are available and their uncertainties are small,the historical solar radiation datasets can also be corrected.And correction effects by the method are better.展开更多
In this study, the clear sky hourly global and net solar irradiances at the surface determined using SUNFLUX, a simple parameterization scheme, for three stations (Gaize, Naqu, and Lhasa) on the Tibetan Plateau were...In this study, the clear sky hourly global and net solar irradiances at the surface determined using SUNFLUX, a simple parameterization scheme, for three stations (Gaize, Naqu, and Lhasa) on the Tibetan Plateau were evaluated against observation data. Our modeled results agree well with observations. The correlation coefficients between modeled and observed values were 〉 0.99 for all three stations. The relative error of modeled results, in average was 〈 7%, and the root-mean-square variance was 〈 27 W m-2. The solar irradiances in the radiation model were slightly overestimated compared with observation data; there were at least two likely causes. First, the radiative effects of aerosols were not included in the radiation model. Second, solar irradiances determined by thermopile pyranometers include a thermal offset error that causes solar radiation to be slightly underestimated. The solar radiation absorbed by the ozone and water vapor was estimated. The results show that monthly mean solar radiation absorbed by the ozone is 〈 2% of the global solar radiation (〈 14 W m-2). Solar radiation absorbed by water vapor is stronger in summer than in winter. The maximum amount of monthly mean solar radiation absorbed by water vapor can be up to 13% of the global solar radiation (95 W m-2). This indicates that water vapor measurements with high precision are very important for precise determination of solar radiation.展开更多
Based on the previous statistical analysis of mesoscale convective systems(MCSs)over the second-step terrain along Yangtze-Huaihe River Valley,eight representative long-lived eastward-propagating MCSs are selected for...Based on the previous statistical analysis of mesoscale convective systems(MCSs)over the second-step terrain along Yangtze-Huaihe River Valley,eight representative long-lived eastward-propagating MCSs are selected for model-based sensitivity testing to investigate the initiation and evolution of these types of MCSs as well as their impact on downstream areas.We subject each MCS to a semi-idealized(CNTL)simulation and a sensitivity(NOLH)simulation that neglects condensational heating in the formation region.The CNTL experiment reveals convection forms in the region downstream of a shortwave trough typified by persistent southwesterly winds in the low-to midtroposphere.Upon merging with other convective systems,moist convection develops into an MCS,which propagates eastward under the influence of mid-tropospheric westerlies,and moves out of the second-step terrain.The MCS then merges with pre-existing local convection over the plains;the merged convection reinforces the cyclonic wind perturbation into a mesoscale vortex at 850 hPa.While this vortex moves eastward to regions with local vortex at 850 hPa,another vortex at 925 hPa is also intensified.Finally,the vortices at 850 and 925 hPa merge together and develop into a mesoscale convective vortex(MCV).In contrast,MCSs fail to form and move eastward in the NOLH experiment.In the absence of eastward-propagating MCSs,moist convection and mesoscale vortices still appear in the plains,but the vortex strength and precipitation intensity are significantly weakened.It is suggested the eastward-propagating MCSs over the second-step terrain significantly impact the development and enhancement of moist convection and vortices in the downstream areas.展开更多
In this study, the water balance-based Precipitation-Evapotranspiration-Runoff (PER) method combined with the land surface model Variable Infiltration Capacity (VIC) was used to estimate the spatiotemporal variations ...In this study, the water balance-based Precipitation-Evapotranspiration-Runoff (PER) method combined with the land surface model Variable Infiltration Capacity (VIC) was used to estimate the spatiotemporal variations of terrestrial water storage (TWS) for two periods, 1982-2005 (baseline) and 2071-2100, under future climate scenarios A2 and B2 in the Yangtze River basin. The results show that the estimated TWS during the baseline period and under the two future climate scenarios have similar seasonal amplitudes of 60-70 mm. The higher values of TWS appear in June during the baseline period and under the B2 scenario, whereas the TWS under A2 shows two peaks in response to the related precipitation pattern. It also shows that the TWS is recharged from February to June during the baseline period, but it is replenished from March to June under the A2 and B2 scenarios. An analysis of the standard derivation of seasonal and interannual TWS time series under the three scenarios demonstrates that the seasonal TWS of the southeastern part of the Yangtze River basin varies remarkably and that the southeastern and central parts of the basin have higher variations in interannual TWS. With respect to the first mode of the Empirical Orthogonal Function (EOF), the inverse-phase change in seasonal TWS mainly appears across the Guizhou-Sichuan-Shaanxi belt, and the entire basin generally represents a synchronous change in interannual TWS. As a whole, the TWS under A2 presents a larger seasonal variation whereas that under B2 displays a greater interannual variation. These results imply that climate change could trigger severe disasters in the southeastern and central parts of the basin.展开更多
The objective of this study is to evaluate the performance of three models for estimating daily evapotranspiration(ET) by employing flux observation data from three years(2007, 2008 and 2009) during the growing season...The objective of this study is to evaluate the performance of three models for estimating daily evapotranspiration(ET) by employing flux observation data from three years(2007, 2008 and 2009) during the growing seasons of winter wheat and rice crops cultivated in a farmland ecosystem(Shouxian County) located in the Huai River Basin(HRB), China. The first model is a two-step model(PM-Kc);the other two are one-step models(e.g., Rana-Katerji(R-K) and advection-aridity(AA)). The results showed that the energy closure degrees of eddy covariance(EC) data during winter wheat and rice-growing seasons were reasonable in the HRB, with values ranging from 0.84 to 0.91 and R2 of approximately 0.80. Daily ET of winter wheat showed a slow decreasing trend followed by a rapid increase, while that of rice presented a decreasing trend after an increase. After calibrating the crop coefficient(Kc), the PM–Kc model performed better than the model using the Kc recommended by the Food and Agricultural Organization(FAO). The calibrated key parameters of the R-K model and AA model showed better universality. After calibration, the simulation performance of the PM-Kc model was satisfactory. Both the R-K model and AA model underestimated the daily ET of winter wheat and rice. Compared with that of the R-K model, the simulation result of the AA model was better, especially in the simulation of daily ET of rice. Overall, this research highlighted the consistency of the PM-Kc model to estimate the water demand for rice and wheat crops in the HRB and in similar climatic regions in the world.展开更多
文摘The development course of China's meteorological movie and television was analyzed firstly, and then the improvement strategies of meteorological movie and television services facing public needs were put forward based on the statistical results of a meteorological service questionnaire.
基金The National Key Research and Development Program of China under contract Nos 2016YFA0602102 and2016YFC1401702the Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)under contract No.GML2019ZD0306+1 种基金the National Natural Science Foundation of China under contract No.41306005CAS Pioneer Hundred Talents Program Startup Fund by South China Sea Institute of Oceanology under contract No.Y9SL011001。
文摘An ensemble optimal interpolation(EnOI)data assimilation method is applied in the BCCCSM1.1 to investigate the impact of ocean data assimilations on seasonal forecasts in an idealized twin experiment framework.Pseudoobservations of sea surface temperature(SST),sea surface height(SSH),sea surface salinity(SSS),temperature and salinity(T/S)profiles were first generated in a free model run.Then,a series of sensitivity tests initialized with predefined bias were conducted for a one-year period;this involved a free run(CTR)and seven assimilation runs.These tests allowed us to check the analysis field accuracy against the"truth".As expected,data assimilation improved all investigated quantities;the joint assimilation of all variables gave more improved results than assimilating them separately.One-year predictions initialized from the seven runs and CTR were then conducted and compared.The forecasts initialized from joint assimilation of surface data produced comparable SST root mean square errors to that from assimilation of T/S profiles,but the assimilation of T/S profiles is crucial to reduce subsurface deficiencies.The ocean surface currents in the tropics were better predicted when initial conditions produced by assimilating T/S profiles,while surface data assimilation became more important at higher latitudes,particularly near the western boundary currents.The predictions of ocean heat content and mixed layer depth are significantly improved initialized from the joint assimilation of all the variables.Finally,a central Pacific El Ni?o was well predicted from the joint assimilation of surface data,indicating the importance of joint assimilation of SST,SSH,and SSS for ENSO predictions.
基金Supported by Soft Science Research Project of Hubei Meteorological Bureau in 2018(02)
文摘Socialization of meteorological services is important guarantee of servicing national major development strategy,strategic selection of adapting to national reform,urgent need of meeting the development of related industries,and necessary way of solving public demand on meticulous,targeted and personalized meteorological services. At present,socialization construction of meteorological services in China still has many problems,such as weak service capability of intelligent weather,inadequate and imbalanced urban-rural and regional development,insufficient sharing and opening of meteorological data,and deficient role of social organization. It should vigorously impel socialization of meteorological services by exploring sharing and opening mechanism of basic meteorological data,establishing policy,regulation and standard system adapting to socialization of meteorological services,establishing operation mechanism for socialization of meteorological services of government dominance combining market,enriching content and means of meteorological socialization service.
文摘In the conflict dialogue between tradition and modernity,Gaomi City practices the theory of creative transformation and innovative development and explores cultural and tourism integration by combining folk customs and tourism in practices and application scenarios.
基金This work was supported by the Major Science and Technology Project of the Science and Technology Department of Tibet under Grant Number XZ202101ZD0015Gthe Second Tibet Plateau Scientific Expedition and Research Program(STEP)under Grant Number 2019QZKK0804.
文摘The Tibet Plateau is one of the regions with the richest solar energy resources in the world.In the process of achieving carbon neutrality in China,the development and utilization of solar energy resources in the region will play an important role.In this study,the gridded solar resource data with 1km resolution in Tibet were obtained by spatial correction and downscaling of SMARTS model.On this basis,the spatial and temporal distribution characteristics of solar energy resources in the region in the past 30 years(1991–2020)are finely evaluated,and the annual global horizontal radiation resource is calculated.The results show that:1)The average annual global horizontal radiation amount in Tibet is 1816 kWh/m^(2).More than 60%of the area belongs to the“Most abundant”(GHI≥1750 kWh/m^(2))area of China’s solar energy resources category A,and nearly 40%belongs to the“Quite abundant”(1400≤GHI<1750)area of China’s solar energy resource category B.2)In space,the solar energy resources in Tibet increased gradually from north to south and from east to west.Lhasa,Central and Eastern Shigatse,Shannan,and Southwestern Ali are the most abundant cities,with a maximum annual radiation level of 2189 kWh/m2.3)In terms of time,the total horizontal radiation in Tibet was the highest in May and the lowest in December.74%of the total area belongs to the“Very stable”(R_(w)≥0.47)area of solar resource stability category A,and 26%belongs to the“stable”(0.36≤R_(w)<0.47)area of solar resource stability category B.Solar energy resources in the region show the characteristics of both strong and stable.Average solar energy resources in the region have shown a fluctuating downward trend over the past 30 years,with an average decline of about 12.86(kWh/m2)per decade.4)In terms of solar radiation resources reaching the earth’s surface,the theoretical total amount of annual horizontal radiation in Tibet is about 240.07 billion tons of standard coal or 222.91 billion kilowatts on average.
基金Innovation and Development Project of China Meteorological Administration(CXFZ2023J044)Innovation Foundation of CMA Public Meteorological Service Center(K2023002)+1 种基金“Tianchi Talents”Introduction Plan(2023)Key Innovation Team for Energy and Meteorology of China Meteorological Administration。
文摘In the present study,multimodel ensemble forecast experiments of the global horizontal irradiance(GHI)were conducted using the dynamic variable weight technique.The study was based on the forecasts of four numerical models,namely,the China Meteorological Administration Wind Energy and Solar Energy Prediction System,the Mesoscale Weather Numerical Prediction System of China Meteorological Administration,the China Meteorological Administration Regional Mesoscale Numerical Prediction System-Guangdong,and the Weather Research and Forecasting Model-Solar,and observational data from four photovoltaic(PV)power stations in Yangjiang City,Guangdong Province.The results show that compared with those of the monthly optimal numerical model forecasts,the dynamic variable weight-based ensemble forecasts exhibited 0.97%-15.96%smaller values of the mean absolute error and 3.31%-18.40%lower values of the root mean square error(RMSE).However,the increase in the correlation coefficient was not obvious.Specifically,the multimodel ensemble mainly improved the performance of GHI forecasts below 700 W m^(-2),particularly below 400 W m^(-2),with RMSE reductions as high as 7.56%-28.28%.In contrast,the RMSE increased at GHI levels above 700 W m^(-2).As for the key period of PV power station output(02:00-07:00),the accuracy of GHI forecasts could be improved by the multimodel ensemble:the multimodel ensemble could effectively decrease the daily maximum absolute error(AE max)of GHI forecasts.Moreover,with increasing forecasting difficulty under cloudy conditions,the multimodel ensemble,which yields data closer to the actual observations,could simulate GHI fluctuations more accurately.
文摘Since ancient times,calligraphy and meteorology have had an inseparable relationship.Wang Xizhi s Prologue to the Collection of Poems Composed at the Orchid Pavilion records the beautiful scenery of mild wind and bright sun,as well as the relaxed and joyful mood of people in such weather.Su Shi s Cold Food Calligraphy Copybook records the scenery of solar terms and the author s psychological changes during these solar terms through calligraphy.The Quick Snow and Clear Time Calligraphy Copybook also reflects the grandeur of snowy days and the customs of literati recording weather and sharing it with friends.In Sun Guoting s Shupu,it is clearly stated that the third element of the"five harmony and five obedience"refers to the clear sky,humid air,and pleasant climate,and excellent climatic conditions are conducive to writing.
基金the National Natural Science Foundation of China,No.81960504the“Xingdian Talents”Support Project of Yunnan Province,No.RLQB20200002+2 种基金the Medical Discipline Reserve Talents of Yunnan Province,No.H-2018015the Applied Basic Research Projects-Union Foundation of Kunming Medical University,No.2017FE467(-132)the Talent Introduction Project of Hubei Polytechnic University,No.21xjz34R。
文摘BACKGROUND Aberrant methylation is common during the initiation and progression of colorectal cancer(CRC),and detecting these changes that occur during early adenoma(ADE)formation and CRC progression has clinical value.AIM To identify potential DNA methylation markers specific to ADE and CRC.METHODS Here,we performed SeqCap targeted bisulfite sequencing and RNA-seq analysis of colorectal ADE and CRC samples to profile the epigenomic-transcriptomic landscape.RESULTS Comparing 22 CRC and 25 ADE samples,global methylation was higher in the former,but both showed similar methylation patterns regarding differentially methylated gene positions,chromatin signatures,and repeated elements.High-grade CRC tended to exhibit elevated methylation levels in gene promoter regions compared to those in low-grade CRC.Combined with RNA-seq gene expression data,we identified 14 methylation-regulated differentially expressed genes,of which only AGTR1 and NECAB1 methylation had prognostic significance.CONCLUSION Our results suggest that genome-wide alterations in DNA methylation occur during the early stages of CRC and demonstrate the methylation signatures associated with colorectal ADEs and CRC,suggesting prognostic biomarkers for CRC.
文摘Cracking during construction is a common occurrence in modern bridge engineering that can directly impact the overall safety of the bridge.Therefore,it is essential to focus on preventing and controlling cracks.As the construction technology for bridge engineering has evolved,the internal quality of construction has significantly improved.However,the appearance quality remains a crucial factor that reflects the technical expertise of a construction company.Therefore,minimizing cracks and improving the appearance quality of concrete are critical issues that require the attention of construction units,supervision departments,and construction companies.This article will analyze the causes of cracking and suggest corresponding prevention and treatment methods.
基金supported by the National Basic Research Program of China(2010CB951502)the Key Technologies R&D Program of China during the 12th Five-Year Plan period(2013BAC09B04)
文摘With consecutive occurrences of drought disasters in China in recent years, it is important to estimate their potential impacts on regional crop production. In this study, we detect the impacts of drought on wheat and maize yield and their changes at a 0.5&#176;&#215;0.5&#176; grid scale in the wheat-maize rotation planting area in the North China Plain under the A1B climate change scenario using the Decision Support System for Agrotechnology Transfer (DSSAT) model and the outputs of the regional climate modeling system-Providing Regional Climates for Impacts Studies (PRECIS). Self-calibrating palmer drought severity index was used as drought recognition indicator. Two time slices used for the study were the baseline (1961-1990) and 40 years of 2011-2050. The results indicate that the potential planting region for double crop system of wheat-maize would expend northward. The statistic conclusions of crop simulations varied considerably between wheat and maize. In disaster-affected seasons, wheat yield would increase in the future compared with baseline yields, whereas in opposite for maize yield. Potential crop yield reductions caused by drought would be lower for wheat and higher for maize, with a similar trend found for the ratio of potential crop yield reductions for both crops. It appears that the negative impact of drought on maize was larger than that on wheat under climate change A1B scenario.
基金National Natural Science Foundation of China(91215302,51278308)Open Project for State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry,Institute of Atmospheric Physics(LAPC)
文摘Leveraging the commercial CFD software FLUENT,the fine-scale three-dimensional wind structure over the Paiya Mountains on the Dapeng Peninsula near Shenzhen,a city on the seashore of South China Sea,during the landfall of Typhoon Molave has been simulated and analyzed.Through the study,a conceptual wind structure model for mountainous areas under strong wind condition is established and the following conclusions are obtained as follows:(1)FLUENT can reasonably simulate a three-dimensional wind structure over mountainous areas under strong wind conditions;(2)the kinetic effect of a mountain can intensify wind speed in the windward side of the mountain and the area over the mountain peak;and(3)in the leeward side of the mountain,wind speed is relatively lower with relatively stronger wind shear and turbulence.
基金supported by the Special Fund for Public Welfare (Meteorology) of China (Grants No. GYHY201006037 and GYHY200906007)
文摘A real-time channel flood forecast model was developed to simulate channel flow in plain rivers based on the dynamic wave theory. Taking into consideration channel shape differences along the channel, a roughness updating technique was developed using the Kalman filter method to update Manning's roughness coefficient at each time step of the calculation processes. Channel shapes were simplified as rectangles, triangles, and parabolas, and the relationships between hydraulic radius and water depth were developed for plain rivers. Based on the relationship between the Froude number and the inertia terms of the momentum equation in the Saint-Venant equations, the relationship between Manning's roughness coefficient and water depth was obtained. Using the channel of the Huaihe River from Wangjiaba to Lutaizi stations as a case, to test the performance and rationality of the present flood routing model, the original hydraulic model was compared with the developed model. Results show that the stage hydrographs calculated by the developed flood routing model with the updated Manning's roughness coefficient have a good agreement with the observed stage hydrographs. This model performs better than the original hydraulic model.
文摘BACKGROUND Interdigestive migrating motor complexes(MMC)produce periodic contractions in the gastrointestinal tract,but the exact mechanism of action still remains unclear.Intramuscular interstitial cells of Cajal(ICC-IM)participate in gastrointestinal hormone and neuromodulation,but the correlation between ICCIM and MMC is also unclear.We found that xiangbinfang granules(XBF)mediated the phase III contraction of MMC.Here,the effects of XBF on gastric antrum motility in W/Wv mice and the effects of ICC-IM on gastric antrum MMC are reported.AIM To observe the effects of ICC-IM on gastric antrum motility and to establish the mechanism of XBF in promoting gastric antrum motility.METHODS The density of c-kit-positive ICC myenteric plexus(ICC-MP)and ICC-IM in the antral muscularis of W/Wv and wild-type(WT)mice was examined by confocal microscopy.The effects of XBF on gastric antrum slow waves in W/Wv and WT mice were recorded by intracellular amplification recording.Micro-strain-gauge force transducers were implanted into the gastric antrum to monitor the MMC and the effect of XBF on gastric antrum motility in conscious W/Wv and WT mice.RESULTS In the gastric antrum of W/Wv mice,c-kit immunoreactivity was significantly reduced,and no ICC-IM network was observed.Spontaneous rhythmic slow waves also appeared in the antrum of W/Wv mice,but the amplitude of the antrum slow wave decreased significantly in W/Wv mice(22.62±2.23 mV vs 2.92±0.52 mV,P<0.0001).MMCs were found in 7 of the 8 WT mice but no complete MMC cycle was found in W/Wv mice.The contractile frequency and amplitude index of the gastric antrum were significantly increased in conscious WT compared to W/Wv mice(frequency,3.53±0.18 cpm vs 1.28±0.12 cpm;amplitude index,23014.26±1798.65 mV·20 min vs 3782.16±407.13 mV·20 min;P<0.0001).XBF depolarized smooth muscle cells of the gastric antrum in WT and W/Wv mice in a dose-dependent manner.Similarly,the gastric antrum motility in WT mice was significantly increased after treatment with XBF 5 mg(P<0.05).Atropine(0.1 mg/kg)blocked the enhancement of XBF in WT and W/Wv mice completely,while tetrodotoxin(0.05 mg/kg)partially inhibited the enhancement by XBF.CONCLUSION ICC-IM participates in the regulation of gastric antrum MMC in mice.XBF induces MMC III-like contractions that enhance gastric antrum motility via ICCIM in mice.
文摘In this paper,new situation faced by meteorological science popularization work of China is analyzed. Based on analyzing the challenges faced by Hubei meteorological science popularization work,the suggestions of Hubei meteorological science popularization work during the " 13 th five-year" period are proposed from four aspects: further optimize operation mechanism of meteorological science popularization work,and improve work efficiency; combine full-time and part-time teams,and promote the fighting capacity of the science popularization team; adapt to the demand of multimedia publicity,and expand the connotation of popular science creation; build brand,and create a stereoscopic science popularization network.
基金supported by the National Key R&D Program of China(Grant Nos.2017YFC1501803 and 2017YFC1502102)。
文摘Assimilation of the Advanced Geostationary Radiance Imager(AGRI)clear-sky radiance in a regional model is performed.The forecasting effectiveness of the assimilation of two water vapor(WV)channels with conventional observations for the“21·7”Henan extremely heavy rainfall is analyzed and compared with a baseline test that assimilates only conventional observations in this study.The results show that the 24-h cumulative precipitation forecast by the assimilation experiment with the addition of the AGRI exceeds 500 mm,compared to a maximum value of 532.6 mm measured by the national meteorological stations,and that the location of the maximum precipitation is consistent with the observations.The results for the short periods of intense precipitation processes are that the simulation of the location and intensity of the 3-h cumulative precipitation is also relatively accurate.The analysis increment shows that the main difference between the two sets of assimilation experiments is over the ocean due to the additional ocean observations provided by FY-4A,which compensates for the lack of ocean observations.The assimilation of satellite data adjusts the vertical and horizontal wind fields over the ocean by adjusting the atmospheric temperature and humidity,which ultimately results in a narrower and stronger WV transport path to the center of heavy precipitation in Zhengzhou in the lower troposphere.Conversely,the WV convergence and upward motion in the control experiment are more dispersed;therefore,the precipitation centers are also correspondingly more dispersed.
基金National Science Foundation of China for Young Scholars(40905071)National Natural Science Foundation of China for General Program(41275114)
文摘Due to the existence of thermal offsets,global solar irradiances measured by pyranometers are smaller than actual values,and errors are larger in the daytime.Until now,there is no universally-recognized correction method for thermal offset errors.Therefore,it is imperative to identify a convenient and effective correction method.Five correction methods were evaluated based on the data measured from a field experiment from 23 January to 15 November,2011.Results have shown:1) Temporal variation characteristics of thermal offsets in the four tested pyranometers are consistent.2) Among the five methods,non-dimensional quantity method is suggested for use to correct thermal offsets,because it is convenient and no modification of instruments is required.If collocated net longwave radiation and wind speed data are available and their uncertainties are small,the historical solar radiation datasets can also be corrected.And correction effects by the method are better.
基金supported by the National Natural Science Foundation of China(GrantNos.40905038,40921003,40775020,and40905071)
文摘In this study, the clear sky hourly global and net solar irradiances at the surface determined using SUNFLUX, a simple parameterization scheme, for three stations (Gaize, Naqu, and Lhasa) on the Tibetan Plateau were evaluated against observation data. Our modeled results agree well with observations. The correlation coefficients between modeled and observed values were 〉 0.99 for all three stations. The relative error of modeled results, in average was 〈 7%, and the root-mean-square variance was 〈 27 W m-2. The solar irradiances in the radiation model were slightly overestimated compared with observation data; there were at least two likely causes. First, the radiative effects of aerosols were not included in the radiation model. Second, solar irradiances determined by thermopile pyranometers include a thermal offset error that causes solar radiation to be slightly underestimated. The solar radiation absorbed by the ozone and water vapor was estimated. The results show that monthly mean solar radiation absorbed by the ozone is 〈 2% of the global solar radiation (〈 14 W m-2). Solar radiation absorbed by water vapor is stronger in summer than in winter. The maximum amount of monthly mean solar radiation absorbed by water vapor can be up to 13% of the global solar radiation (95 W m-2). This indicates that water vapor measurements with high precision are very important for precise determination of solar radiation.
基金supported by the National Key R&D Program of China(Grant No.2018YFC1507200)the National Natural Science Foundation of China(Grant No.41975057).
文摘Based on the previous statistical analysis of mesoscale convective systems(MCSs)over the second-step terrain along Yangtze-Huaihe River Valley,eight representative long-lived eastward-propagating MCSs are selected for model-based sensitivity testing to investigate the initiation and evolution of these types of MCSs as well as their impact on downstream areas.We subject each MCS to a semi-idealized(CNTL)simulation and a sensitivity(NOLH)simulation that neglects condensational heating in the formation region.The CNTL experiment reveals convection forms in the region downstream of a shortwave trough typified by persistent southwesterly winds in the low-to midtroposphere.Upon merging with other convective systems,moist convection develops into an MCS,which propagates eastward under the influence of mid-tropospheric westerlies,and moves out of the second-step terrain.The MCS then merges with pre-existing local convection over the plains;the merged convection reinforces the cyclonic wind perturbation into a mesoscale vortex at 850 hPa.While this vortex moves eastward to regions with local vortex at 850 hPa,another vortex at 925 hPa is also intensified.Finally,the vortices at 850 and 925 hPa merge together and develop into a mesoscale convective vortex(MCV).In contrast,MCSs fail to form and move eastward in the NOLH experiment.In the absence of eastward-propagating MCSs,moist convection and mesoscale vortices still appear in the plains,but the vortex strength and precipitation intensity are significantly weakened.It is suggested the eastward-propagating MCSs over the second-step terrain significantly impact the development and enhancement of moist convection and vortices in the downstream areas.
基金supported by the National Basic Research Program of China under Grants 2010CB951001 and 2010CB428403the National Natural Science Foundation of China under Grant 41075062the R&D Special Fund for Public Welfare Industry (Meteorology) under Grant GYHY201006037
文摘In this study, the water balance-based Precipitation-Evapotranspiration-Runoff (PER) method combined with the land surface model Variable Infiltration Capacity (VIC) was used to estimate the spatiotemporal variations of terrestrial water storage (TWS) for two periods, 1982-2005 (baseline) and 2071-2100, under future climate scenarios A2 and B2 in the Yangtze River basin. The results show that the estimated TWS during the baseline period and under the two future climate scenarios have similar seasonal amplitudes of 60-70 mm. The higher values of TWS appear in June during the baseline period and under the B2 scenario, whereas the TWS under A2 shows two peaks in response to the related precipitation pattern. It also shows that the TWS is recharged from February to June during the baseline period, but it is replenished from March to June under the A2 and B2 scenarios. An analysis of the standard derivation of seasonal and interannual TWS time series under the three scenarios demonstrates that the seasonal TWS of the southeastern part of the Yangtze River basin varies remarkably and that the southeastern and central parts of the basin have higher variations in interannual TWS. With respect to the first mode of the Empirical Orthogonal Function (EOF), the inverse-phase change in seasonal TWS mainly appears across the Guizhou-Sichuan-Shaanxi belt, and the entire basin generally represents a synchronous change in interannual TWS. As a whole, the TWS under A2 presents a larger seasonal variation whereas that under B2 displays a greater interannual variation. These results imply that climate change could trigger severe disasters in the southeastern and central parts of the basin.
基金supported by the National Natural Science Foundation of China (41905100)the Anhui Provincial Natural Science Foundation, China (1908085QD171)+3 种基金the Anhui Agricultural University Science Foundation for Young Scholars, China (2018zd07)the Anhui Agricultural University Introduction and Stabilization of Talent Fund, China (yj2018-57)the National Key Research and Development Program of China (2018YFD0300905)the Postgraduate Research and Practice Innovation Program of Jiangsu Province, China (KYCX17_0885)。
文摘The objective of this study is to evaluate the performance of three models for estimating daily evapotranspiration(ET) by employing flux observation data from three years(2007, 2008 and 2009) during the growing seasons of winter wheat and rice crops cultivated in a farmland ecosystem(Shouxian County) located in the Huai River Basin(HRB), China. The first model is a two-step model(PM-Kc);the other two are one-step models(e.g., Rana-Katerji(R-K) and advection-aridity(AA)). The results showed that the energy closure degrees of eddy covariance(EC) data during winter wheat and rice-growing seasons were reasonable in the HRB, with values ranging from 0.84 to 0.91 and R2 of approximately 0.80. Daily ET of winter wheat showed a slow decreasing trend followed by a rapid increase, while that of rice presented a decreasing trend after an increase. After calibrating the crop coefficient(Kc), the PM–Kc model performed better than the model using the Kc recommended by the Food and Agricultural Organization(FAO). The calibrated key parameters of the R-K model and AA model showed better universality. After calibration, the simulation performance of the PM-Kc model was satisfactory. Both the R-K model and AA model underestimated the daily ET of winter wheat and rice. Compared with that of the R-K model, the simulation result of the AA model was better, especially in the simulation of daily ET of rice. Overall, this research highlighted the consistency of the PM-Kc model to estimate the water demand for rice and wheat crops in the HRB and in similar climatic regions in the world.