在风暴中经受考验——评20集电视剧《热带风暴》

由中国电视剧制作中心与武警部队电视艺术中心联合摄制的20集电视剧《热带风暴》，通过南方某特区城市武警部队的组建以及发展过程，塑造了一批富有鲜明时代特征而又肩负特殊使命的军人形象，从一个侧面反映了我国武警部队的真实现状，令人感动。

热带风暴

热带风暴，一听就是一个既刺激又有趣的乐园。于是，我和老妈二话不说，一起来到了水的世界一热带风暴：

EFFECTS OF LOW-LATITUDE MONSOON SURGE ON THE INCREASE IN DOWNPOUR FROM TROPICAL STORM BILIS

By using the dataset of CMA-STI Tropical Cyclone Optimal Tracks, NCEP/NCAR reanalysis and intensive surface observations, a study is performed of the influences of a low-latitude monsoon surge on the longer persistence and increase in torrential rains from the landing tropical storm Bilis. Results suggest that the southwest monsoon was anomalously active after Bilis came ashore. The westerly winds in Bilis's south side might give rise to the poleward movement of the SW monsoon, thus enlarging the pressure gradient between Bilis and the anticyclonic circulation to the south with the result of greatly intensified SW monsoon, which fueled plentiful water vapor, heat and momentum into the declining Bilis and allowed its long stay over land instead of erosion and disappearance. Before Bilis's landfall, the 2006 East Asian monsoon surge, characterized by the atmospheric ISO, experienced remarkable northward propagation. After landfall, the strong surge and powerful low frequency vapor convergence were just on the south side of Bilis, resulting in sharply increased rainfall. In addition, a broad belt of high-valued vapor fluxes extended from the eastern Arabian Sea via the Bay of Bengal, Indochina Peninsula and the South China Sea into the south of China. The belt was linked with the SW monsoon surge forming a moist tongue stretching from the Bay of Bengal to the south of China, which supplied continuously abundant vapor for Bilis along with the surge propagating poleward.

A Potential High-Score Scheme for the Prediction of Atlantic Storm Activity

A new empirical approach for the seasonal prediction of annual Atlantic tropical storm number (ATSN) was developed using precipitation and 500 hPa geopotential height data from the preceding January February and April May.The 2.5°×2.5° resolution reanalysis data from both the US National Center for Environmental Prediction/the National Center for Atmospheric Research (NCEP/NCAR) and the European Center for Medium-Range Weather Forecasting (ECMWF) were applied.The model was cross-validated using data from 1979 2002.The ATSN predictions from the two reanalysis models were correlated with the observations with the anomaly correlation coefficients (ACC) of 0.79 (NCEP/NCAR) and 0.78 (ECMWF) and the multi-year mean absolute prediction errors (MAE) of 1.85 and 1.76,respectively.When the predictions of the two models were averaged,the ACC increased to 0.90 and the MAE decreased to 1.18,an exceptionally high score.Therefore,this new empirical approach has the potential to improve the operational prediction of the annual tropical Atlantic storm frequency.

Features of Ocean Surface Winds Observed by the QuikSCAT Satellite Before Tropical Cyclogenesis over the South China Sea

Ocean surface winds observed by the Quick Scatterometer(QuikSCAT) satellite prior to the geneses of 36 tropical cy-clones(TCs) in the South China Sea(SCS) are investigated in this paper. The results show that there are areas with negative mean horizontal divergence around the TC genesis locations three days prior to TC formation. The divergence term [-(f+ζ)(u/x+v/y) ] in the vorticity equation is calculated based upon the QuikSCAT ocean surface wind data. The calculated mean divergence term is about 10.3 times the mean relative vorticity increase rate around the TC genesis position one day prior to TC genesis,which shows the important contributions of the divergence term to the vorticity increase prior to TC formation. It is suggested that criteria related with the divergence and divergence term be applied in early detections of tropical cyclogenesis using the QuikSCAT satellite data.

VARIATION CHARACTERISTICS OF TROPICAL CYCLONES MAKING LANDFALL IN CHINA AT DIFFERENT INTENSITIES

According to the national standard(2006)on tropical cyclone(TC)intensity,TCs are categorized into six intensity types,namely,tropical depression(TD),tropical storm(TS),severe tropical storm(STS), typhoon(TY),severe typhoon(STY),and super severe typhoon(SSTY).Fifty-eight years(1949–2006)of the datasets from the Yearbook of Typhoons and Yearbook of Tropical Cyclones were used to study the variation characteristics of TCs making landfalls in China's Mainland,Hainan and Taiwan islands.The main results are as follows.First,interannual or interdecadal variations in the number of landfalling TCs at different intensities exist.As far as long-term trends are concerned,the TD and TS frequencies show a significant linearly decreasing trend while those of STY show a significant linearly increasing trend.Second, a significant period of 6–8 years exist in the variations of annual landfalling TD,TS,and STS frequencies while quasi-16-year periods are found in the annual TY frequency.Third,TD and TS are generated mostly over the South China Sea,while TY,STY,and SSTY mostly over the waters southeast of the Bashi Channel and the ocean to the east of the Philippines.Fourth,as far as interdecadal trends are concerned,the frequencies of landfalling TD and TS generated over the South China Sea show significant linearly decreasing trends.However,TY and STY show significant linearly increasing trends.

Statistical Analysis of Tropical Disturbances over the South China Sea During 1997-2006

Tropical disturbances over the South China Sea (SCS) during the period of 1997-2006 are analyzed using the Tropical Storm and Hurricane WX products. A total of 158 tropical disturbances were formed over the SCS from 1997 to 2006, with 54 de-veloping tropical disturbances which developed into tropical depressions and 104 non-developing tropical disturbances which never developed into tropical depressions. The development rate of tropical disturbances into tropical depressions was 34.18% in these ten years. During the period of this study, total annual numbers of tropical disturbances and developing tropical disturbances over the SCS had significant decreasing trends; however, the development rate of tropical disturbances had an insignificant increasing trend.

ANALYSIS OF AMBIENT FIELDS AND SATELLITE IMAGERY CHARACTERISTICS OF EFFECT OF BAY OF BENGAL STORMS ON LOW- LATITUDE PLATEAU

Based on the composite analysis method, 12 rainstorms triggered by Bay of Bengal storms (shortened as B-storms hereafter) across the whole province of Yunnan were studied, and some interesting results of rain and circulation characteristics influenced by the storms were obtained for low-latitude plateau. Usually, when a rainstorm weather occurs in low-latitude plateau, the B-storm center locates in the central, east or north parts of the Bay of Bengal. At the same time, the subtropical high ridge moves to 15°N– 20°N and the west ridge point moves to the Indo-china Peninsula from the South China Sea and the low-latitude plateau is controlled by southwest air streams coming from the front of the trough and the periphery of the subtropical high. The southwest low-level jet stream from the east side of the bay storm has great effect on heavy rains. On the one hand, the southwest low-level jet stream is playing the role of transporting water vapor and energy. On the other hand, the southwest low-level jet stream is helpful to keep essential dynamical condition. From the analysis of the satellite cloud imagery, it is found that mesoscale convection cloud clusters will keep growing and moving into the low-latitude plateau to cause heavy rains when a storm forms in the Bay of Bengal.

SIMULATION STUDY ON CAUSES OF TROPICAL STORM FITOW (0114) HEAVY RAIN

With PSU/NCAR nonhydrostatic mesoscale model MM5, the rainfall process of tropical storm Fitow(0114) is simulated for 00:00 UTC 31 Aug. – 00:00 UTC 2 Sept. 2001. Mesoscale separation is performed on the results with the filtering scheme. Analyses show that the MM5 model well reproduced the position and intensity of heavy rain. Mesoscale characteristics of heavy rain were well represented in rainfall time scale, rainfall area, stream field and divergence at lower and upper levels. The interaction between inverted typhoon troughs and the mesoscale systems lead to heavy rain occurrence. The distribution of divergence fields at lower and upper levels can have a kind of indication for the rainfall. Heavy rains are closely associated with topography and land-sea distribution in South China. Weak instability is favorable to the generation of heavy rain.

Coral Bleaching in Arrecifes de Cozumel National Park after Tropical Storm Rina in October 2011

Extensive bleaching of Montastrea annularis spp. group and several other scleractinian taxa occurred on the reefs within the Arrecifes de Cozumel National Park of Cozumel, Mexico, after the passage of Hurricane/Tropical Storm Rina. We conducted six drift dives at five different dive sites （-13 h of scuba diving） and photographed a variety of reefs scenes at depths of 10-28 m. Bleaching was noted at depths of 10-40 m in a variety of scleractinian species, including M. annularis species group, especially M. faveolata and Siderastrea siderea. Considering that local dive guides had not observed bleaching prior to the storm and the sea surface temperature did not exceed the local bleaching threshold, it is probable that the extensive rainfall associated with Hurricane/Tropical Storm Rina lowered salinity sufficiently via subsurface freshwater springs to cause bleaching in susceptible species. This suggests the need to monitor not only subsurface sea temperature but also subsurface salinity in localities where freshwater springs occur adjacent to or within coral reefs.

Determination of design parameter for three-product heavy-medium cyclone

Analyzed the selected raw coal nature and forecasted the number quality of its separated product. Considering each product＇s density, volume, and suspending liquid assignment, combining the separating mechanism of the cyclone and the rela- tive formulas obtained from scientific experimentation and practice, the structure parameter was determined by calculation. This provides a more scientific reasonable method for determining the structure parameter of the unpressurized feeding three-product heavy-medium cyclone.

Investigating the Effect of Winds and Storms on Shoreline Erosion along the Coast of Tanzania

Wind data spanning 28 years （1977-2004） from four meteorological stations （Tanga, Zanzibar, Dar es Salaam and Mtwara） were analyzed to elucidate the effect of winds on coastal erosion along the coast of Tanzania. The investigation entailed wavelet analysis of the time series of winds which were related with past erosion events at each site. The study also analyzed qualitatively the incidences of tropical storms in relation to coastal erosion events along the coast. The results revealed that most of the critical erosion incidents in the past few decades were associated with periods of occurrence of extreme wind speeds and tropical storms. Furthermore, the results indicated that the wind speeds and the frequency and intensity of tropical storms had generally been increasing during the past three decades. The findings were consistent to those recently reported for the coast of Dar es Salaam. The increasing trends of winds and storms are considered to have direct impact on the wave climate with increased risk of shoreline wave-induced erosion that is already affecting relatively many parts of Tanzania.

An Elliptical Wind Field Model of Typhoons

An elliptical wind field model of typhoons is put forward based on the characteristics of the typhoon wind fields occurring in the Yellow Sea and Bohai Sea. By contrasting it with the circular typhoon wind field model, it is found that the elliptical model can adequately represent the real wind field and trace the process of a typhoon storm surge. The numerically simulated results of storm surges by using the elliptical model are in good agreement with the observations and markedly better than those by using the circular model.

DIAGNOSTIC ANALYSIS OF A RAINSTORM IN SHANDONG PENINSULA INFLUENCED BY A DISTANT TROPICAL DEPRESSION

Based on the observational data as well as data of satellite, NCEP reanalysis and moist potential vortex, the heavy rainfall event that occurred away from the outer cycle of tropical depression Kaemi (No.0605) on July 27, 2006 in Shandong Peninsula has been analyzed. The results show that there are three severe convective cloud clusters during the heavy rainfall. The uprightness of coupling pattern between upper-layer jet and low jet and a divergence area, which appeared in the right of upper-layer jet, provided favorable environmental conditions for convective cloud clusters. The strong convective weather happens over the prefrontal warm sector and the storm rainfall mainly distributes in the front of a high-energy area. Positive vorticity distribution and transportation of warm advection in low levels provide dynamic and thermal conditions for the rainstorm. The spatial-temporal evolvements of physical variable fields and MPV2 as the horizontal component of moist potential vorticity show that the rain intensity change is determined by upper and low level jets and the area of MPV2>0 occurs at the front of the low jet cores.

Numerical Model of Storm Surge and Inundation in Bohai Bay

A two-dimensional numerical model of extratropical storm surge and inundation in Bohai Bay was built based on the unsteady flow Navier-Stokes equations. The model included two sections, one was for the simulation of storm surge tidal level and the other for the simulation of storm surge inundation in the coastal area. While simulating the storm surge tidal level, the alternating direction implicit (ADI) method was applied to dispersing and solving 2D storm surge equations. In the simulation of storm surge inundation, the 2D unsteady flow equations were dispersed and solved using the structureless grids of finite volume method (FVM). A coupling calculation mode of the process of inundation and storm surge tidal level variation was proposed, therefore the storm surge inundation process and area could be calculated while simulating and forecasting the process of storm surge tidal setup. Furthermore, an extratropical storm surge and inundation in Bohai Bay were simulated using this numerical model. Simulation results are in good agreement with the measured data, which shows that this numerical model provides a new method of simulating and forecasting storm surge and inundation in Bohai Bay.

诗词四首

热带风暴 风生水起浪打墙， 鼠窜鱼惊舟泊航。 行人匆匆寻蔽所，

Can the tropical storms originated from the Bay of Bengal impact the precipitation and soil moisture over the Tibetan Plateau?

This study investigates the impacts of tropical storms originated from the Bay of Bengal(BOBTSs) on the precipitation and soil moisture over the Tibetan Plateau(TP) in April–June(AMJ) and September–December(SOND) during 1981–2011 based on the best track dataset provided by Joint Typhoon Warning Centre(JTWC). Results indicate that there are about 1.35 BOBTSs influence the TP in each year and most of them occurred in May and October, and the BOBTSs in AMJ influence the TP with larger extension and higher latitudes than those in SOND. The maximum regional precipitation induced by the BOBTSs accounts for more than 50% for the total precipitation in the corresponding month and about 20% for the season. Further analysis reveals that the surface soil moisture anomalies induced by the BOBTSs can persist only 20–25 days in AMJ, and the case is also true for the snow depth in SOND. Numerical simulations by using the regional climate model of Weather Research and Forecasting(WRF) suggest that the soil moisture anomalies in the sub-surface can last 2 months whereas for the surface it can persist only about 20 days, which agrees well with the observation analysis. Overall, the effect of the preceding BOBTSs on the snow depth and soil moisture anomalies over the TP cannot maintain to summer, and there is no robust connection between the BOBTSs and summer precipitation anomalies in East China. Moreover, since the mid-1990 s, the spring rainfall induced by the BOBTSs over the TP seems to be enhanced to a certain degree because of the intensified BOBTSs.

Tropical storm-forced near-inertial energy dissipation in the southeast continental shelf region of Hainan Island

Near-inertial motion is an important dynamic process in the upper ocean and plays a significant role in mass, heat, and energy transport across the thermocline. In this study, the dissipation of wind-induced near-inertial energy in the thermocline is investigated by using observation data collected in July and August 2005 during the tropical storm Washi by a moored system at(19°35′N, 112°E) in the continental shelf region off Hainan Island. In the observation period, the near-inertial part dominated the observed ocean kinetic energy and about 80% of the near-inertial energy dissipated in the upper layer. Extremely strong turbulent mixing induced by near-inertial wave was observed in the thermocline, where the turbulent energy dissipation rate increased by two orders of magnitude above the background level. It is found that the energy loss of near-inertial waves in the thermocline is mainly in the large-scales. This is different from the previous hypothesis based on "Kolmogorov cascade" turbulence theory that the kinetic energy is dissipated mainly by small-scale motions.