Bias-Corrected Short-Range Ensemble Forecasts for Near-Surface Variables during the Summer Season of 2010 in Northern China

A running mean bias （RMB） correction ap- proach was applied to the forecasts of near-surface variables in a seasonal short-range ensemble forecasting experiment with 57 consecutive cases during summer 2010 in the northern China region. To determine a proper training window length for calculating RMB, window lengths from 2 to 20 days were evaluated, and 16 days was taken as an optimal window length, since it receives most of the benefit from extending the window length. The raw and 16-day RMB corrected ensembles were then evaluated for their ensemble mean forecast skills. The results show that the raw ensemble has obvious bias in all near-surface variables. The RMB correction can remove the bias reasonably well, and generate an unbiased ensemble. The bias correction not only reduces the ensemble mean forecast error, but also results in a better spreaderror relationship. Moreover, two methods for computing calibrated probabilistic forecast （PF） were also evaluated through the 57 case dates： 1） using the relative frequency from the RMB-eorrected ensemble; 2） computing the forecasting probabilities based on a historical rank histogram. The first method outperforms the second one, as it can improve both the reliability and the resolution of the PFs, while the second method only has a small effect on the reliability, indicating the necessity and importance of removing the systematic errors from the ensemble.

In-situ experiment investigations of hydrothermal process of highway in deep seasonal frozen soil regions of Inner Mongolia, China

To reveal the influencing factors and changing rules for the hydrothermal interaction process of highway subgrade, the field measurements of Shiwei-Labudalin Highway in Inner Mongolia, China was conducted for 3 years, based on which the freezing-thawing rules and water content changing characteristics were analyzed. The main results show the subgrade presents a frequent freezing-thawing alternation, and the water content of subgrade exhibits an obvious seasonal alternation. The subbase has the maximum water content, while the base has the minimum water content. The change of water flux is concentrated in the thawing period and consistent with the change of temperature gradient. The subbase layer has the most active water flux due to the heat absorption and impermeability of pavement that easily causes the water accumulation in this layer. Therefore, the prevention and treatment for the freezing-thawing disease should be started from heat insulation and water resistance.

THE EFFECTS OF GENERAL CIRCULATION ANOMALIES ON PRECIPITATION IN THE RAINING SEASON OF SHANDONG

Using the monthly mean reanalysis data of height, wind and vertical velocity of NCEP/NCAR from 1958 to 2003, the characteristics of 500hPa height anomalies in the Northern Hemisphere, convergence and divergence on the levels of 200hPa and 925hPa and vertical stream over the Shandong province were studied and compared with that over North China. The study shows that the teleconnection pattern called East Asia-Pacific pattern (EAP) plays important roles in the summer rainfall of Shandong. Weaker Okhotsk sea high, stronger upward stream over tropical areas and Shandong and northward location of subtropical high and stronger Indian low, are likely to lead to more rain in Shandong province in summer, but there are some flood (drought) years in which these characteristics such as the location and intensity of subtropical high change with the least extent. The difference between Shandong and North China in 500hPa height is that there is a teleconnection pattern called Europe / Asia pattern in North China, while there is a negative East Asia Pattern in Shandong during drought years. There is a teleconnection relation between Shandong summer rainfall and convective activities happening in tropical areas in spring and summer accomplished by the Rossby waves. During the flood years in Shandong, the convective activities happening in tropical India Ocean and tropical west Pacific and Walker circulation are much stronger than that during the drought years, but the convective activities happening in tropical east Pacific are weaker than those during the drought years.

Subdaily to Seasonal Change of Surface Energy and Water Flux of the Haihe River Basin in China: Noah and Noah-MP Assessment

The land surface processes of the Noah-MP and Noah models are evaluated over four typical landscapes in the Haihe River Basin(HRB) using in-situ observations. The simulated soil temperature and moisture in the two land surface models(LSMs) is consistent with the observation, especially in the rainy season. The models reproduce the mean values and seasonality of the energy fluxes of the croplands, despite the obvious underestimated total evaporation. Noah shows the lower deep soil temperature. The net radiation is well simulated for the diurnal time scale. The daytime latent heat fluxes are always underestimated, while the sensible heat fluxes are overestimated to some degree. Compared with Noah, Noah-MP has improved daily average soil heat flux with diurnal variations. Generally, Noah-MP performs fairly well for different landscapes of the HRB. The simulated cold bias in soil temperature is possibly linked with the parameterized partition of the energy into surface fluxes. Thus, further improvement of these LSMs remains a major challenge.

Hydrological Processes in the Huaihe River Basin, China： Seasonal Variations, Causes and Implications

Understanding streamflow changes in terms of trends and periodicities and relevant causes is the first step into scientific management of water resources in a changing environment. In this study, monthly streamflow variations were analyzed using Modified Mann-Kendall(MM-K) trend test and Continuous Wavelet Transform(CWT) methods at 9 hydrological stations in the Huaihe River Basin. It was found that: 1) streamflow mainly occurs during May to September, accounting for 70.4% of the annual total streamflowamount with Cv values between 0.16–0.85 and extremum ratio values between 1.70–23.90; 2) decreased streamflow can be observed in the Huaihe River Basin and significant decreased streamflow can be detected during April and May, which should be the results of precipitation change and increased irrigation demand; 3) significant periods of 2–4 yr were detected during the 1960 s, the 1980 s and the 2000 s. Different periods were found at stations concentrated within certain regions implying periods of streamflow were caused by different influencing factors for specific regions; 4) Pacific Decadal Oscillation(PDO) has the most significant impacts on monthly streamflow mainly during June. Besides, Southern Oscillation Index(SOI), North Atlantic Oscillation(NAO) and the Ni?o3.4 Sea Surface Temperature(Ni?o3.4) have impacts on monthly streamflow with three months lags, and was less significant in time lag of six months. Identification of critical climatic factors having impacts on streamflow changes can help to predict monthly streamflow changes using climatic factors as explanatory variables. These findings were well corroborated by results concerning impacts of El Nino-Southern Oscillation(ENSO) regimes on precipitation events across the Huaihe River Basin. The results of this study can provide theoretical background for basin-scale management of water resources and agricultural irrigation.

The Rise and Fall of Social Networking Sites： A Comparative Study of Cyworld and Facebook

This study examines why some social networking sites （SNSs） stagnate while other SNSs grow by comparing Cyworld with Facebook. Cyworld was one of the most successful SNSs in the world, but its international expansion efforts failed. Facebook＇s open technology has had considerable influence on various sectors of the economy and society and allowed it to become a dominant SNS at the global level, whereas Cyworld has remained a local SNS. Facebook＇s open platform and application programming interface （API） pose a serious challenge to Cyworld＇s walled-garden approach. Cyworld is based on strong ties fostering close relationships, whereas Facebook expands social networks through its open and weak ties and has more network power than Cyworld. Therefore, openness is the main reason behind the rise of Facebook and the fall of Cyworld.

A Portable Fall Detection and Alerting System Based on k-NN Algorithm and Remote Medicine

This paper presents information on a portable fall detection and alerting system mainly consisting of a custom vest and a mobile smart phone. A wearable motion detection sensor integrated with tri-axial accelerometer, gyroscope and Bluetooth is built into a custom vest worn by elderly. The vest can capture the reluctant acceleration and angular velocity about the activities of daily living(ADLs) of elderly in real time. The data via Bluetooth is then sent to a mobile smart phone running a fall detection program based on k-NN algorithm. When a fall occurs the phone can alert a family member or health care center through a call or emergent text message using a built in Global Positioning System. The experimental results show that the system discriminates falls from ADLs with a sensitivity of 95%, and a specificity of 96.67%. This system can provide remote monitoring and timely help for the elderly.

Does regional air–sea coupling improve the simulation of the summer monsoon over the western North Pacific in the WRF4 model?

A new regional coupled ocean–atmosphere model,WRF4-LICOM,was used to investigate the impacts of regional air–sea coupling on the simulation of the western North Pacific summer monsoon(WNPSM),with a focus on the normal WNPSM year 2005.Compared to WRF4,WRF4-LICOM improved the simulation of the summer mean monsoon rainfall,circulations,sea surface net heat fluxes,and propagations of the daily rainband over the WNP.The major differences between the models were found over the northern South China Sea and east of the Philippines.The warmer SST reduced the gross moist stability of the atmosphere and increased the upward latent heat flux,and then drove local ascending anomalies,which led to the increase of rainfall in WRF4-LICOM.The resultant enhanced atmospheric heating drove a low-level anomalous cyclone to its northwest,which reduced the simulated circulation biases in the stand-alone WRF4 model.The local observed daily SST over the WNP was a response to the overlying summer monsoon.In the WRF4 model,the modeled atmosphere exhibited passive response to the underlying daily SST anomalies.With the inclusion of regional air–sea coupling,the simulated daily SST–rainfall relationship was significantly improved.WRF4-LICOM is recommended for future dynamical downscaling of simulations and projections over this region.

Oxygen Stable Isotopic Ratio in Precipitations in Niigata Prefecture, Japan

Time-course of oxygen stable isotopic ratios （i.e., δ^18O） as well as seasonal variation of δ^18O has been examined to investigate the characteristics, sources and the passing route of precipitations in Niigata Prefecture. The precipitation samples have been mainly collected with a filtrating bulk sampler at the rooftop of Niigata University. Furthermore, backward trajectories analyses have been also conducted for these samples taken sequentially for a short period. Consequently, the following features have been mainly clarified for the precipitations in Niigata Prefecture： （1） the δ^18O values varied between -14.57%o and -3.86%0 in the precipitations of Niigata University; （2） as for the comparison among sampling points, the mean value of δ^18O at seaside spots （i.e., Niigata City： -6.93%0） is larger than that of inland spots （Sanjyo City： -8.68%0）; （3） δ^18O value was generally small in the rainy or typhoon season, and relatively large in summer; （4） decreasing δ^18O content with time is a predominant feature of sequentially sampled rainfalls as predicted by Rayleigh models of atmospheric vapor condensation.

Fluridone： An Effective Approach to Control Phelipanche aegyptiaca in Potato Crop

Field studies were conducted to evaluate the efficacy of fluridone （PestanalR） for Phelipanche aegyptiaca control and the tolerance of potato cultivar to single or repeated foliar application of fluridone during 2012 and 2013 growing seasons. Fluridone was sprayed on potato leaves at rates of l, 5, 10, 20 and 30 μM/ha. Each rate was tested for single and sequential application at 20 d and 35 d after potato emergence. Results indicated that fluridone at all the tested rates （single or sequential applications） significantly reduced Phelipanche infestation and shoot number compared to the control. Fluridone at 10 μM/ha reduced Phelipanche infestation by 99% when applied twice （20 d and 35 d after potato emergence）. All tested rates except for fluridone at 30μM/ha （single or two applications） were selective in potato and had no negative effect on potato growth and yield as compared to the control.

Spatial and seasonal dynamics of soil loss ratio in mountain rangelands of south-western Kyrgyzstan

Vegetation cover is the main factor of soil loss prevention.The C-factor of the RUSLE(Revised Universal Soil Loss Equation) was predicted with NDVI,ground data and exponential regression equation for mountain rangelands of Kyrgyzstan.Time series of C-factor,precipitation and temperature were decomposed into seasonal and trend components with STL(seasonal decomposition by loess) to assess their interrelations.C-factor,precipitation and temperature trend components indicated significant lagged correlation,whereas seasonal components indicated more complex relations with climate factors which can be promoting as well as limiting factors for vegetation development,depending on the season.Rainy springs and hot summers may increase soil loss dramatically,whereas warm and dry springs with rainy summers can decrease it.Steep slopes indicated higher soil loss ratio,whereas flat areas were better protected by vegetation.

Variation law of microscopic pore of loess-like soil after several freeze-thaw cycles in seasonal frozen soil region

In seasonal frozen soil region,the engineering geological properties of loess-like soil will be deteriorated after freeze-thaw cycles.Through the freeze-thaw cycle experiment of remolded loess-like soil,under different freezing temperatures,the authors carried out freeze-thaw cycle tests for 3 times and 20 times,respectively.With mercury intrusion porosimetry and granulometric analysis,from the micro-structure,the authors studied the law that freeze-thaw cycle times and frozen temperature effect on the variation of microscopic pore of loesslike soil.This result can provide theoretical basis for comprehensive treatment of problems in the construction of the project in seasonal frozen loess-like soil region.

Rainfall and Tillage Impacts on Soil Erosion of Sloping Cropland with Subtropical Monsoon Climate- A Case Study in Hilly Purple Soil area, China

Under global warming, storm events tend to intensify, particularly in monsoon-affected regions. As an important agricultural area in China, the purple soil region in the Sichuan Basin, where it has a prevailing monsoon climate, is threatened by serious soil erosion. Tillage operations alter runoff and soil erosion processes on croplands by changing the physical properties of the soil surface. To clarify the relationship between tillage and soil erosion in the purple soil region, three different tillage practices in this region were investigated at the plot scale over 4 years： bare land with minimum tillage （BL）, conventional tillage （CT） and seasonal no-tillage ridges （SNTR） which was initially designed to prevent soil erosion by contoured ridges and no-tillage techniques. The results showed that although there were no significant differences in the surface runoff and soil erosion among the three oractices, BL caused relatively high surface runoff and soil erosion, followed by CT and SNTR. Classification and comparison of the rainfall events based on cluster analysis （CA） verified that the surface runoff was not significantly different between most intensive event and long intensive events but was significantly different between most intensive and short and medium-duration events. Only the rainfall events with the highest rainfall intensity could trigger serious soil erosion, up to 1000 kg ha^-1 in the region. Further detailed investigations on the effects of tillage operations on the soil erosion in a subtropical region with a monsoon climate are needed to provide a basis for modeling catchments and designing better management practices.

Study on measures for water prevention and control in Chengchao Iron Mine,China

The gush-out water in the mineral pit endangers the underground mine safety directly. It is an important task for underground mine to guarantee its safety during the flood season. The authors analyzed the status of water prevention and control in Chengchao Iron Mine,China,and put forward the necessary measures. The hydrogeological parameter controls the design of mine water prevention and affects the mineral well safety in operation. Enhance supervision and control,keeping the current facilities intact,using the existing pump house and the underground tunnel to adjust and control the amount of water and improving the hydrogeological conditions in the mine are the practical and remedial measures.

A DIAGNOSTIC ANALYSIS OF THE WEAKENING OF WEST PACIFIC SUBTROPICAL ANTICYCLONE DURING THE PERIOD OF SOUTH CHINA SEA SUMMER MONSOON ONSET IN 1998

The onset of South China Sea summer monsoon in 1998 occurred on May 21st. Using the U.S. National Centers for Environmental Prediction reanalysis data, this paper examines the physical process of the weakening of a subtropical anticyclone in West Pacific during the onset period using the Zwack-Okossi vorticity equation. Results show that during the pre-onset period, the positive vorticity advection in front of an upper tropospheric trough was the most dominant physical mechanism for the increase of the cyclonic vorticity on the 850-hPa layer over the South China Sea and its nearby region. The secondary contribution to the increase of the cyclonic vorticity was the warm-air advection. After the onset, the magnitude of the latent-heat warming term rapidly increased and its effect on the increase of the cyclonic vorticity was about the same as the positive-vorticity advection. The adiabatic term and divergence term contributed negatively to the increase of the cyclonic vorticity most of the time. Thus, the positive vorticity advection is the most important physical mechanism for the weakening of the West Pacific subtropical anticyclone over the South China Sea during the onset period.

Parameters for Use of BEWAB＋ Programme to Schedule Irrigation of Pea （Pisum sativum L,）

A large portion of irrigation farmers make use of subjective （intuition） irrigation scheduling methods as supposed to objective or scientific irrigation scheduling methods, which need to be changed. The BEsproeiingsWAterbestuursprogram （BEWAB＋） irrigation scheduling programme is based on the water balance equation and needs： （1） a crop production function; （2） a relative consumptive water demand curve and （3） an allowable depletion subroutine. The objective of this paper was to describe research aimed at obtaining information on （1） and （2） for pea and also to describe the effect of water application on yield and water use of pea. BEWAB＋ uses this information to estimate the daily irrigation water requirements for a particular soil-crop-atmosphere system under irrigation. A field experiment, based on published line-source irrigation methodology, was conducted on a 3 m deep loamy fine sand Bainsvlei or Ustic Quartzipsamment soil near Bloemfontein （26°08′S; 29°01′E） in South Africa. Results showed that there is a linear relationship of the form Ys = 8.07ET - 249 （r2 = 0.91）, where Ys is the seed yield of pea （kg/ha） and ET is evapotranspiration for the growing season （mm）. The relative consumptive water demand curve is represented by the following third order polynomial function that describes the relationship between time and relative ET for a pea growing season of 120 days： ETrelx = 0.09419646 - 0.01302413x ＋ 0.00059008x2 - 0.00000371x3. ETrelz denotes relative ET and x denotes time in days. A workable balance between practical problem solving and advanced irrigation science has been established with BEWAB＋. Pre-plant irrigation schedules can be made for semi-arid areas with the BEWAB＋ programme using easily obtainable inputs, like target yield, soil depth and soil particle size distribution information.

Predicting climate anomalies:A real challenge

In recent decades,the damage and economic losses caused by climate change and extreme climate events have been increasing rapidly.Although scientists all over the world have made great efforts to understand and predict climatic variations,there are still several major problems for improving climate prediction.In 2020,the Center for Climate System Prediction Research(CCSP) was established with support from the National Natural Science Foundation of China.CCSP aims to tackle three scientific problems related to climate prediction—namely,El Ni?o-Southern Oscillation(ENSO) prediction,extended-range weather forecasting,and interannual-to-decadal climate prediction—and hence provide a solid scientific basis for more reliable climate predictions and disaster prevention.In this paper,the major objectives and scientific challenges of CCSP are reported,along with related achievements of its research groups in monsoon dynamics,land-atmosphere interaction and model development,ENSO variability,intraseasonal oscillation,and climate prediction.CCSP will endeavor to tackle key scientific problems in these areas.

The Onset of the Monsoon over the Bay of Bengal:The Year-to-Year Variations

In situ buoy observation data spanning four years(2008-2011) were used to demonstrate the year-to-year variations of the monsoon onset processes in the Bay of Bengal(BoB).A significant early(late) monsoon onset event in 2009(2010) was analyzed in detail.It is found that the year-to-year variations of monsoon onset can be attributed to either the interannual variability in the BoB SST or the irregular activities of the intra-seasonal oscillation(ISO).This finding raises concern over the potential difficulties in simulating or predicting the monsoon onset in the BoB region.This uncertainty largely comes from the unsatisfactory model behavior at the intra-seasonal time scale.

Mathematical Modelling of Charge/Discharge Process in Seasonal Heat Storage Tank

The seasonal heat storage tank is the most important component of the SDH （solar district heating） system, which allows significant increase in the share of solar energy in heat supply in comparison with conventional solar systems with short-term accumulation of heat. The adverse impact of their investment sophistication on competitiveness may be compensated by the increased use. For example： Cooperation with heat pump allows to increase the accumulation capacity of the seasonal heat storage tank and causes the direct use of heating energy and accumulation of cooling energy produced by heat pump. In the final stage of the heating period, it can be used to remote cooling supplied buildings. Experimentation on mathematical model is possible to obtain valuable insights about the dynamics of the processes of charging and discharging in the seasonal storage tank and subsequently used in the design, implementation and operation.

《槐园梦忆》:举梦齐眉

《槐园梦忆》是梁实秋对逝去时光的深切回忆,书中文字皆源于生活中的一些零零碎碎的琐事,却蕴含着革故鼎新、发人深省的道理,足以让人看懂看透世事,教人感念至深。在他眼里,妻子程季淑是一个“轻柔而低缓”的女子.