2013武汉购物旅游季拉开序幕 亮点纷呈

集实惠购物、美食、旅游、游乐等为一体、让广大市民和游客尽享幸福欢乐的"2013武汉购物旅游节"9月16日崭新亮相。这次购物旅游节以"展示武汉城市魅力,体验购物旅游乐趣"为主题,从今年9月中旬持续到2014年2月,囊括中秋、国庆、圣诞、元旦和春节等节日,形成节中有节氛围。举全市商贸旅游业之力办好2013武汉购物旅游节,打组合拳。武汉市人民政府主办。

2016马来西亚国际家具展(MIFF)回顾 创销售新高并笑迎众多海外买家

据统计,3月闭幕的2016年马来西亚国际家具展（MIFF）创下9.08亿美元的销售记录,并吸引了众多海外买家,其中包括许多首次到访的国际买家,为2016年的亚洲采购季拉开了序幕。MIFF共有500家来自15个国家和地区的企业参展,并吸引了近20,000买家,凸显了本年度家具展会季中,作为东南亚首要家具商贸展的领头羊地位。MIFF 2016于3月1日至5日,假吉隆坡太子世界贸易中心（PWTC局会展中心）及外贸促进（MECC）举行。到访的国际买家同比增加了3%,达5,340人,其中30%是首次到访的买家。

REASONS FOR THE LATE ONSET AND ANOMALOUS SOUTHWARD PERSISTENCE OF THE SOUTH CHINA SEA SUMMER MONSOON IN 2005

Features of atmospheric circulation and thermal structures are discussed using the NCAR/NCEP data to reveal the reasons for the late onset and anomalous southward persistence of the South China Sea Summer Monsoon(SCSSM) in 2005.The results show that three factors are crucial.First,a strong Arabian High overlaps with a high-latitude blocking high and channels strong cold air to southern Asia.Second,the Tibetan Plateau has a bigger snow cover than usual in spring and the melting of snow cools down the surface.Third,the Somali Jet breaks out at a much later date,being not conducive to convection over Indochina.The former two factors restrict atmospheric sensible heating over the Tibetan Plateau and nearby regions while the third one limits latent heating over Indochina.All of the factors slow down atmospheric warming and postpone the onset of SCSSM.Long after the onset of SCSSM,strong cold air over India advances the Southwest Monsoon northward slowly,resulting in weaker convection and latent heating over the Tibetan Plateau and nearby areas.The negative feedback conversely inhibits further northward movement of Southwest Monsoon.

The Interannual Variations of Summer Precipitation in the Northern Indian Ocean Associated with ENSO

Using rainfall data from the Global Precipita- tion Climatology Project （GPCP）, NOAA extended reconstruction sea surface temperature （ERSST）, and NCEP/NCAR reanalysis, this study investigates the interannual variation of summer rainfall southwest of the Indian Peninsula and the northeastern Bay of Bengal associated with ENSO. The composite study indicates a decreased summer rainfall southwest of the Indian Penin- sula and an increase in the northeastern Bay of Bengal during the developing phase, but vice versa during the decay phase of E1 Nifio. Further regression analysis dem- onstrates that abnormal rainfall in the above two regions is controlled by different mechanisms. Southwest of the Indian Peninsula, the precipitation anomaly is related to local convection and water vapor flux in the decay phase of E1 Nifio. The anomalous cyclone circulation at the lower troposphere helps strengthen rainfall. In the northeastern Bay of Bengal, the anomalous rainfall depends on the strength of the Indian southwest summer monsoon （ISSM）. A strong/weak ISSM in the developing/decay phase of E1 Nifio can bring more/less water vapor to strengthen/weaken the local summer precipitation.

Temperature Inversion in the Bay of Bengal Prior to the Summer Monsoon Onsets in 2010 and 2011

Freshwater input such as runoff and rainfall can enhance stratification in the Bay of Bengal(BOB) through the formation of a "barrier layer",which can lead to the formation of a temperature inversion.The authors focused on the temperature inversion in spring,especially before the onset of the summer monsoon,because previous research has mainly focused on the temperature inversion in winter.Using the hydrographic data from two cruises performed during 24-30 April 2010 and 1-4 May 2011,the authors found that inversions appeared at two out of nine Conductivity-Temperature-Depth Recorder(CTD) stations across the 10°N section and at seven out of 13 CTD stations across the 6°N section in the BOB.In 2010,the inversions(at stations N02 and N05) occurred at depths of approximately 50-60 meters,and their formation was caused by the advection of cold water over warm water.In 2010,the N02 inversion was mainly influenced by the warm saline water from the east sinking below the cold freshwater from the west,while the N05 inversion was affected by the warm saline water from its west sinking below the cold freshwater from its east.In 2011,the inversions appeared at depths of 20-40 meters(at stations S01,S02,S07,S08,and S09) and near 50 m(S12 and S13).The inversions in 2011 were mainly caused by the net heat loss of the ocean along the 6°N section.

Intensity of the Trough over the Bay of Bengal and Its Impact on the Southern China Precipitation in Winter

In this study, the intensity of the trough over the Bay of Bengal (BBT) and its association with the southern China precipitation, the Madden-Julian Oscillation (MJO) and the Rossby wave propagation along the African-Asian subtropical Jet stream (AASJ) are investigated on the intraseasonal time scale. The results show that the intensity of the BBT affects the southern China precipitation more directly and to a greater degree than the MJO. The peak amplitude of the BBT tended to occur in phase-3 of the MJO. The strong BBT was substantially modulated by the Rossby wave propagation along the AASJ, which was triggered by the anomalous upstream circulation similar to the pattern of the North Atlantic Oscillation (NAO). Therefore, from the perspective of medium- and extended-range weather forecasts, the NAO- like pattern may be regarded as a precursory signal for the strong BBT and thus the southern China precipitation.

Maintenance and development of the Ural high and its contribution to severe cold wave activities in winter 2020/21

Two successive severe cold waves invaded eastern China from the end of 2020 to early 2021,leading to an extensive,severe,and persistent drop in temperature.The paper investigates the features and formation mechanisms of the two cold waves.The main results are as follows:(1)An anticlockwise turning of the transverse trough was observed in both cold waves.However,a broad ridge was maintained over the Ural area from mid-December 2020 till mid-January 2021.No breakdown or discontinuous westward shift of the blocking high was observed,which is different from typical cold waves in eastern Asia.(2)The maintenance and strengthening of northerly winds in front of the Ural high led to an increase in baroclinicity in-situ.In the downstream region,the gradient of the geopotential height contour in the south of the transverse trough rapidly increased and the advection of cold temperature consistently enhanced and advanced southwards.This in turn caused the intensification and southward expansion of the Siberian high.(3)Energy propagation of the quasi-stationary wave was a reason for the development and persistence of the Ural blocking.Prior to the occurrence of the two cold waves,the energy of the low-frequency stationary wave originating from near 0°E(or even to the west)propagated eastwards,which helped the Ural ridge intensify and maintain.Meanwhile,it also contributed to the development of the trough downstream of the ridge and resulted in the anticlockwise turning of the transverse trough,providing a favorable condition for the southward outbreak of cold air.

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.

The Onset of the Monsoon over the Bay of Bengal:The Observed Common Features for 2008-2011

In situ buoy observation data spanning four years(2008-2011) were collected and used to perform a composite analysis of the monsoon onset process in the Bay of Bengal(BoB).The sea surface temperature(SST) in the central BoB increases dramatically during the monsoon transition period and reaches its annual maximum just before the onset of the monsoon.This process is illustrated by the northward-propagating deep convection phase of the intraseasonal oscillation and the establishment of a steady southwest wind.It is argued that the SST peak plays a potential role in triggering the onset of the monsoon in the BoB and its vicinity.The general picture of the BoB monsoon onset summarized here reveals the possibility of regional land-ocean-atmosphere interaction.This possibility deserves further examination.

TYPICAL STRONG AND WEAK SOUTH ASIAN SUMMER MONSOON YEARS AND SEA SURFACE TEMPERATURE OF ARABIAN SEA

The South Asian Summer Monsoon （SASM） is an important member of the monsoon system for Asia. It is made up of low-level subsystems of the Mascarene high in the Southern Hemisphere, cross-equatorial Somali jet stream, 850-hPa westerly jet over the Arabian Sea, Indian monsoon trough north of the Bay of Bengal through west India and upper-level tropical easterly jet centered at 5°N and South Asia high centered at 30°N. During the summer monsoon, convection is intense in South Asia, with large scale and in association with abundant amount of latent heat release from condensation. Its anomalies affect not only the industrial and agricultural production and people＇s life in South Asia, but also the southwestern part of China. SASM is therefore drawing attention from quite a number of meteorologists from home and abroad. For instance, in their search for indicators of the summer monsoon in the region, Parthasarathy et al. Webster et al. and Goswami et al. defined a number of indexes based on precipitation and circulation. Wang et al.studied existing, widely-used indexes and came up with different regional indexes for the circulation and convection of SASM. Hahn et al.worked on the effect of topography on SASM. With wind field data, Wang et al. divided the years by the intensity of SASM and analyzed the characteristics of interannual variation and circulation for strong and weak years of monsoon. They found that the SASM intensified and weakened as a whole and there were four types of monsoon, being wholly strong and weak, stronger in the west than in the east and weaker in the west than in the east. Yan et al.discow,＇red sharp differences in individual members of the SASM at upper and lower levels over middle and lowe,r latitudes in both strong and weak years of the monsoon. Using, the dynamics method, Zhu et al. took the South Asia winter and summer monsoons as two stable equilibrium states and discussed the formation mechanism from the viewpoint of non-linear equilibrium theory. Their result further shows that in addition to thermal difference between land and sea, the topographic effect of South Asia also has significant restraints and influence on the formation and activity of the monsoon

Intraseasonal variation of the East Asian summer monsoon in La Ni?a years

Based on the composite result of six major the intraseasonal variation of the East Asian La Nina events during 1979-2012, the authors reveal summer monsoon （EASM） and summer rainfall in East Asia in La Nino years. Due to a higher SST over the western Pacific warm pool in the proceeding winter and spring, warm pool convection in summer is enhanced, leading to a cyclonic anomaly in the subtropical western Pacific. As a result, the western Pacific subtropical high is located more northeastward, and the seasonal march in East Asia is thus accelerated.This anomalous pattern tends to change with the seasonal march, with a maximum anomaly in July. Besides, there is less Mei-yu rainfall in the Yangtze River basin, with an earlier start and termination. The rainfall distribution in East Asia during La Nino years is characterized bya zonal pattern of less rainfall in eastern China and more rainfall over the oceanic region of the western Pacific. By comparison, a meridional pattern is found during El Nino years, with less rainfall in the tropics and more rainfall in the subtropics and midlatitudes. Therefore, the influence of La Nino on the EASM cannot be simply attributed to an antisymmetric influence of El Nino.

The Characteristics of Mesoscale Convective Systems (MCSs) over East Asia in Warm Seasons

Mesoscale convective system (MCS) cloud clusters,defined using an objective recognition analysis based on hourly geostationary infrared satellite data over East Asia during the warm seasons of 1996-2008 (except 2004),were investigated in this study.The geographical pattern of MCS distribution over East Asia shows several high-frequency centers at low latitudes,including the Indo-China peninsula,the Bay of Bengal,the Andaman Sea,the Brahmaputra river delta,the south China coastal region,and the Philippine Islands.There are several middle-frequency centers in the middle latitudes,e.g.,the central-east of the Tibet Plateau,the Plateau of west Sichuan,Mount Wuyi,and the Sayan Mountains in Russia;whereas in Lake Baikal,the Tarim Basin,the Taklimakan Desert,the Sea of Japan,and the Sea of Okhotsk,rare MCS distributions are observed.MCSs are most intensely active in summer,with the highest monthly frequency in July,which is partly associated with the breaking out and prevailing of the summer monsoon in East Asia.An obvious diurnal cycle feature is also found in MCS activities,which shows that MCSs are triggered in the afternoon,mature in the evening,and dissipate at night.MCS patterns over East Asia can be characterized as small,short-lived,or elongated,which move slowly and usually lead to heavy rains or floods.

An Analysis of the Characteristics of Monsoon Onset over the Bay of Bengal and the South China Sea in 2010

Based on NCEP/NCAR daily reanalysis and the Tropical Rainfall Measuring Mission data, the back- ground atmospheric circulation and the characteristics of meteorological elements during the period of the Bay of Bengal monsoon （BOBM） and the South China Sea （SCS） monsoon （SCSM） in 2010 are studied. The impacts of the BOBM onset on the SCSM onset and the relationship between the two monsoons are also analyzed. The two main results are as follows： （l） The BOBM onset obvi- ously occurs earlier than the SCSM onset in 2010, which is a typical onset process of the Asian monsoon. During the BOBM＇s onset, northward jump, and eastward expansion, convective precipitation and southwest winds occurred over the SCS, which resulted in the onset of the SCSM. （2） The relationship among strong convection, heavy rainfall, and vertical circulation configuration is obtained during the monsoon onsets over the BOB and SCS, and it is concluded that the South Asian High plays an important role in this period.

Association of Indian Ocean ITCZ Variations with the Arctic Oscillation during Boreal Winter

In this study,the authors analyzed the associations between the Arctic Oscillation(AO)and the tropical Indian Ocean(TIO)intertropical convergence zone(ITCZ)in boreal winter for the period 1979–2009.A statistically significant AO-TIO ITCZ linkage was found.The ITCZ vertical air motion is significantly associated with the AO,with upward(downward)air motion corresponding to the positive(negative)AO phase.The Arabian Sea anticyclone plays a crucial role in linking the AO and the TIO ITCZ.The Arabian Sea vorticity is strongly linked to high-latitude disturbances in conjunction with jet stream waveguide effects of disturbance trapping and energy dispersion.During positive(negative)AO years,the Arabian Sea anticyclone tends to be stronger(weaker).The mean vorticity over the Arabian Sea,averaged from 850hPa to 200 hPa,has a significant negative correlation with AO(r=0.63).The anomalous anticyclone over the Arabian Sea brings stronger northeastern winds,which enhance the ITCZ after crossing the equator and result in greater-than-normal precipitation and minimum outgoing long-wave radiation.

Reversal of monthly East Asian winter air temperature in 2020/21 and its predictability

In this study,the reversal of monthly East Asian winter air temperature(EAWT) in 2020/21 and its predictability were investigated.The reversal of monthly EAWT in 2020/21 was characterized by colder temperatures in early winter(December 2020 to mid-January 2021) and warmer temperatures in late winter(mid-January to February 2021).Results show that the reversal in the intensity of the Siberian high(SH) also occurred between early and late winter in 2020/21.In early winter,as the Barents-Laptev sea ice in the previous September(i.e., in2020) reached a minimum for the period 1981-2020,the SH was strengthaned via a reduction of the meridional gradient between the Arctic and East Asia.In late winter,as a sudden stratospheric warming occurred on 5 January 2021,the stratospheric polar vortex weakened,with the weakest center shifting to North America in January.Subsequently,the negative Arctic Oscillation-like structure shifted towards North America in the middle and lower troposphere,which weakened the SH in late winter.Furthermore,the predictability of the reversal in EAWT in 2020/21 was validated based on monthly and daily predictions from NCEP-CFSv2(National Centers for Environment Prediction-Climate Forecast System,version 2).The results showed that the model was unable to reproduce the monthly reversal of EAWT.However,it was able to forecast the reversal date(18 January 2021)of EAWT at lead times of 1-20 days on the daily scale.

Reproductive Seasonality of Opsaridium microlepis （Mpasa） in the Linthipe River in Central Malawi

Opsaridium microlepis migrates for spawning during the rainy season （November to May） to major affluent rivers. Linthipe River is one of the major rivers, into which this species migrates. Determination of reproductive seasonality of O. microlepis is paramount in the improved management of this endangered species. Reproductive seasonality ofO. microlepis in the Linthipe River in Central Malawi was estimated using 546 specimens for 12 months. The GSI （Gonadosomatic Index） ranged between 5.6% and 13% for females and between 0.3% and 1.4% for males, respectively. GSI variation between the months was significantly different （one-way ANOVA （analysis of variance）, P 〈 0.05）. The peak breeding activity was observed between January to April. This was at the onset of rainy season while the condition factor of O. microlepis was found to be variable with lowest value in the month of August. The study revealed that for O. microlepis fishery to be sustainably exploited, proper management regimes should be instituted along the migratory rivers during the peak breeding periods. These sustainable methods need to be managed in a participatory manner together with the majority of people living along these rivers.

Recent Climatic Effects on Seasonal Rice Yields in Bangladesh： A Statistical Overview

Expecting that agricultural yield is highly dependent on climatic conditions, particularly water availability and suitable temperature, an agroclimatic study was carried out on rice crops during three different seasons in four regions of Bangladesh. Data on climate （surface air temperature and precipitation） and seasonal rice production were examined for the period 1986-2006 from 18 rice growth observatories. The relationship between climate and rice production was statistically analyzed by removing long-term trends so that the effects of improved irrigation, which results in a general increase in crop production, may be removed. The analysis involved both single and multiple regressions. The results suggested that, during monsoon and summer, higher temperatures had negative effects on rice production, especially in the northwestern （NW） region. In winter, positive effects were observed throughout Bangladesh. Since the annual mean temperature was positively correlated with those in the three seasons individually, the annual temperature had negative effects on the annual rice production only in the NW region, while it had positive effects in the central and southern regions. With the exception of the NW region, it was basically dry, excessive rainfall both in summer and monsoon yielded floods and reduced rice yield. In winter, more rainfall showed positive effects on crop production only in the central region, which was least irrigated. These findings suggested that accelerated atmospheric warming would result in serious damage to crops during summer and monsoon. Reliable prediction of future crop production will rely on the temperature and rainfall trends in individual seasons.

Seasonal waterbird population changes in Lashihai Lake in northwest Yunnan, China

We studied the waterbird population at Lashihai Lake, Yunnan Province, China, which is a Ramsar Site(Wetland of International Importance), to determine seasonal variation in the species composition and size of the waterbird population. The study was conducted at five selected spots along Lashihai Lake at the same time each week from August 2011 to September 2013. In total, 62 waterbird species were recorded, of which 38.71%, 35.48%, 16.13%, and 9.68% were winter migrants, passage visitors, residents, and summer migrants, respectively. We found important seasonal changes in waterbird species composition and population size. Waterbird species richness was highest from September to the following April, with the total species numbers peaking in December. Total individual numbers peaked twice from late November to early December and mid-to-late February. However, waterbird species and individual numbers were comparatively lower from May to August. The change in species composition was determined by the arrival and departure dynamics of winter migrants and passage visitors. Winter migrants primarily caused the periodic changes in population size. Of concern,species and overall waterbird numbers seemed to be lower than the numbers in historical records. The decline of waterbird numbers implies that environmental changes caused by the implementation of the dam upstream of Lashihai Lake may have had adverse effects on this waterbird population. This study confirms the existence of major seasonal changes in species composition and size of the waterbird population at Lashihai Lake. Furthermore, the findings demonstrate that this wetland is of high conservation importance for waterbirds using the Central Asian–Indian and Asian–Pacific migratory routes.

Influence of Summer Monsoon on Asymmetric Bimodal Pattern of Tropical Cyclogenesis Frequency over the Bay of Bengal

The influence of summer monsoon on tropical cyclone (TC) genesis over the Bay of Bengal (BoB) is explored using an empirical genesis potential (GP) index. The annual cycle of cyclogenesis frequency over the BoB shows an asymmetric bimodal pattern with the maximum genesis number appearing in late October and the second largest in early May. The two peaks correspond to the withdrawal and onset of the BoB summer monsoon, respectively. The semimonthly GP index calculated without TC days over the BoB is consistent with TC genesis frequency, indicating that the index captures the monsoon-induced changes in the environment that are responsible for the seasonal variation of TC genesis frequency. Of the four environmental variables (i.e., low-level vorticity, mid-level relative humidity, potential intensity, and vertical wind shear) that enter into the GP index, the potential intensity makes the largest contribution to the bimodal distribution, followed by vertical wind shear due to small wind speed during the summer monsoon onset and withdrawal. The difference in TC genesis frequency between autumn and late spring is mainly owing to the relative humid-ity difference because a divergence (convergence) of horizontal moisture flux associated with cold dry northerlies (warm wet wester-lies) dominates the BoB in late spring (autumn).