Application of Argo Data in the Analysis of Water Masses in the Northwest Pacific Ocean

The temperature and salinity distributions, and the water mass structures in Northwest Pacific Ocean are studied using the temperature and salinity data obtained by Argo profiling floats. The T-S relation in this region indicates there exist 8 water masses, they are the North Pacific Tropical Surface Water （NPTSW）, North P, acific Subsurface Water （NPSSW）, North Pacific Intermediate Water （NPIW）, North Pacific Subtropical Water （NPSTW）, North Pacific Deep Water （NPDW） and Equatorial Surface Water （ESW）, and the South Pacific Subsurface Water （SPSSW） and South Pacific Intermediate Water （SPIW）.

The first record of Ophioleila elegans (Echinodermata:Ophiuroidea) from a deep-sea seamount in the Northwest Pacific Ocean

The rare ophiuroid species, Ophioleila elegans, was collected by the submersible Jiaolongfrom 1 660 m depth on the Caiwei Guyot located in the Magellan Seamount Chain in the Northwest Pacific Ocean. This is the first published record of this species since the types were described from similar habitat off Hawaii. We provide more detailed morphologic characteristics of arm skeleton and a phylogenetic analysis based on CO 1 sequences. Both morphology and phylogeny results suggest that the genus Ophioleila is more closely related to Ophiactids than Hemieuryalids.

Non-Stationary Variation of Tropical Cyclones Activities in the Northwest Pacific

Based on the analysis of tropical cyclone （TC） database in the Northwest Pacific （NWP） from 1945 to 2008, we not only extract the temporal variation of TC intensity and frequency, but also give their spatial distribution both in the NWP and in the South China Sea （SCS）. The results show that there is an observational increase of TC activities, which manifests as the enhancement of the power dissipation index （PDI） and the growth of TC frequency, especially for typhoons and strong typhoons. The inbomogeneous spatial distributions of TC frequency and intensity are also provided both in the NWP and in the SCS. For example, the region of Zhongsha Islands and Dongsha Islands in the SCS （15°-22°N, 115° - 120°E）, west to the Philippine Islands is the place with frequent occurrence of strong typhoons, among which the wind speed of 7 TCs in 64 years exceeds 60 m/s.

Influences of two types of El Ni?o event on the Northwest Pacific and tropical Indian Ocean SST anomalies

Based on the Had ISST1 and NCEP datasets,we investigated the influences of the central Pacific El Ni?o event(CP-EL)and eastern Pacific El Ni?o event(EP-EL)on the Sea Surface Temperature(SST)anomalies of the Tropical Indian Ocean.Considering the remote ef fect of Indian Ocean warming,we also discussed the anticyclone anomalies over the Northwest Pacific,which is very important for the South China precipitation and East Asian climate.Results show that during the El Ni?o developing year of EP-EL,cold SST anomalies appear and intensify in the east of tropical Indian Ocean.At the end of that autumn,all the cold SST anomaly events lead to the Indian Ocean Dipole(IOD)events.Basin uniform warm SST anomalies exist in the Indian Ocean in the whole summer of EL decaying year for both CP-and EP-ELs.However,considering the statistical significance,more significant warm SST anomalies only appear in the North Indian Ocean among the June and August of EP-EL decaying year.For further research,EP-EL accompany with Indian Ocean Basin Warming(EPI-EL)and CP El Ni?o accompany with Indian Ocean Basin Warming(CPI-EL)events are classified.With the remote ef fects of Indian Ocean SST anomalies,the EPI-and CPI-ELs contribute quite differently to the Northwest Pacific.For the EPI-EL developing year,large-scale warm SST anomalies arise in the North Indian Ocean in May,and persist to the autumn of the El Ni?o decaying year.However,for the CPI-EL,weak warm SST anomalies in the North Indian Ocean maintain to the El Ni?o decaying spring.Because of these different SST anomalies in the North Indian Ocean,distinct zonal SST gradient,atmospheric anticyclone and precipitation anomalies emerge over the Northwest Pacific in the El Ni?o decaying years.Specifically,the large-scale North Indian Ocean warm SST anomalies during the EPI-EL decaying years,can persist to summer and force anomalous updrafts and rainfall over the North Indian Ocean.The atmospheric heating caused by this precipitation anomaly emulates atmospheric Kelvin waves accompanied by low level easterly anomalies over the Northwest Pacific.As a result,a zonal SST gradient with a warm anomaly in the west and a cold anomaly in the east of Northwest Pacific is generated locally.Furthermore,the atmospheric anticyclone and precipitation anomalies over the Northwest Pacific are strengthened again in the decaying summer of EPI-EL.Af fected by the local WindEvaporation-SST(WES)positive feedback,the suppressed East Asian summer rainfall then persists to the late autumn during EPI-EL decaying year,which is much longer than that of CPI-EL.

Tidal harmonic analysis of TOPEX/POSEIDON data in the Northwest Pacific by introducing difference-ratio relations

The difference-ratio relations are introduced to separate tidal constituents that are aliaseddue to the sampling interval and sampling span of the TOPEX/POSEIDON altimeter. It is found that some tidal constituents such as K_1 and SSA, though aliased at along track points, are not aliased at crossover points beeause the data at crossover points are double those at along track points. So the harmonic analysis method can be employed directly for the analysis of time series at crossover points. Then the difference-ratio relations from crossover points are introduced to analyze the time series at along track points. The TOPEX/POSEIDON data in the Northwest Pacific are analyzed with this method. The results from this method agree well with tidal constants from tidal gauges.

New Stage of the Northwest China 330 kV Power System Development - A Brief Introduction of System Planning in Northwest China to the Year 2000

The system planning of the Northwest China 330 kV Power System from present to the year 2000 is introduced in this paper. Some technical problems arising from the system planning, such as network configuration, system stability and reactive power compensation etc. are also briefly summarized.

Using Bayesian Bio-economic model to evaluate the management strategies of Ommastrephes bartramii in the Northwest Pacific Ocean

The neon flying squid(Ommastrephes bartramii)in the Northwest Pacific Ocean is one economically important cephalopod,largely exploited by squid jigging fleets from Chinese Mainland,Japan,and Chinese Taibei.In this study,a Bayesian Bio-economic model was developed using fishery data from Chinese Mainland,Japan,and Chinese Taibei,and relevant fishery economic data from Chinese Mainland.The stock assessment and risk analysis of alternative management strategies for O.bartramii were carried out.Three prior distributions(i.e.,uniform,normal and logarithmic normal)for model parameters were assumed in different scenarios.The results showed that the estimated model parameters and reference points such as maximum sustainable yield(MSY),maximum economic yield(MEY),bio-economic balance point(BE)and fishing mortality were similar in the scenarios of normal and logarithmic normal prior assumptions.However,the estimates were larger in the scenario of uniform prior assumption.The fishing mortalities and annual catches from 1996 to 2008 were lower than the reference points F_(0.1) and MSY in all the three scenarios,indicating that O.bartramii stock is at sustainable exploited level.The results of decision analysis indicated that under the same harvest rate,the catch and biomass in 2023 from the uniform assumption were the highest.However,the highest probability of the collapse was found for squid resources after 2023.Our findings suggested that the harvest rate of 0.4 appeared to be the best management regulation under the uniform assumption,and the MSY would be 200 thousand tons.In addition,the harvest rate of 0.5 would be the best management regulation under the other two assumptions,and the MSY would be 180 thousand tons,which balanced the desire for high yields and the healthy population.The results of this study could be used to provide management suggestions for neon flying squid in the Northwest Pacific Ocean.

A DIAGNOSTIC STUDY OF AN EXPLOSIVELY DEEPENING OCEANIC CYCLONE OVER THE NORTHWEST PACIFIC

The vertical motions and secondary circulation of an explosively deepening oceanic cyclone,which oc- curred over the Northwest Pacific Ocean and was in conjunction with 200 hPa-level jet stream and has central pressure falls of 33.9 hPa/24h,have been computed from seven-level nonlinear balance model and Saw- yer-Eliassen-Shapiro equation for the transverse ageostrophic circulation.The vertical motions are partitioned into contributions from large-scale latent heat release,effect of cumulus heating,thermal advection,differen- tial vorticity advection,etc.,while the secondary circulation stream function is partitioned into contributions from geostrophic deformation,transfer of momentum and heat in the area of cumulus and diabatic heating. The principal results are the following.Large-scale latent heat release is very crucial to the explosive de- velopment of cyclones.If there is enough transfer of moisture,the positive feedback process between ascent of air and large-scale heating would work.The cumulus heating and the transfer of momentum and heat in the area of cumulus play an important role during the explosively deepening stage.Thermal advection is the initial triggering condition for large-scale heating and the conditional instability for the convection of cumulus.

MEDIUM-RANGE OSCILLATION AND TELECONNECTION OF THE ATMOSPHERIC CIRCULATION SYSTEMS OVER THE NORTHWEST PACIFIC AND SOUTH INDIAN OCEANS

This paper aims to demonstrate some characteristics of the 20-50 day oscillations of certain circulation systems in low latitudes during the northern summer seasons.The teleconnection between the variations of the Mascarene high and the Northwest Pacific high and its physical mechanism are studied.How the Mas- carene high plays an important role in the interaction between the atmospheric circulations of both hemispheres is discussed.

Estimation of extreme wind speed in SCS and NWP by a non-stationary model

In offshore engineering design, it is considerably significant to have an adequately accurate estimation of marine environmental parameters, in particular, the extreme wind speed of tropical cyclone （TC） with different return periods to guarantee the safety in projected operating life period. Based on the 71-year （1945-2015） TC data in the Northwest Pacific （NWP） by the Joint Typhoon Warning Center （JTWC） of US, a notable growth of the TC intensity is observed in the context of climate change. The fact implies that the traditional stationary model might be incapable of predicting parameters in the extreme events. Therefore, a non-stationary model is proposed in this study to estimate extreme wind speed in the South China Sea （SCS） and NWP. We find that the extreme wind speeds of different return periods exhibit an evident enhancement trend, for instance, the extreme wind speeds with different return periods by non- stationary model are 4.1%-4.4% higher than stationary ones in SCS. Also, the spatial distribution of extreme wind speed in NWP has been examined with the same methodology by dividing the west sea areas of the NWP 0°-45°N, 105°E-130°E into 45 subareas of 5° × 5°, where oil and gas resources are abundant. Similarly, remarkable spacial in-homogeneity in the extreme wind speed is seen in this area： the extreme wind speed with 50-year return period in the subarea （15°N-20°N, 115°E-120°E） of Zhongsha and Dongsha Islands is 73.8 m/s, while that in the subarea of Yellow Sea （30°N-35°N, 120°E-125°E） is only 47.1 m/s. As a result, the present study demonstrates that non-stationary and in-homogeneous effects should be taken into consideration in the estimation of extreme wind speed.

The ecological system and the regionalization of landscape reconstruction in northwest of China

The northwest of China is a vast area with abundant resources and significant potential for development.However,the ecological system is extremely vulnerable to damage and must be managed carefully.Thus,the Chinese government is strengthening research on improvement and reconstruction of the ecological system and landscape in northwest of China while moving forward with large-scale development in west China.The disadvantages and vulnerabilities in the northwest area in China are presented.It is suggested that the reconstruction of landscape should be conducted by step by step regionalization across the various ecological systems in the 3.04 million km^(2) northwest area of China.The first level regionalization results of reconstruction of landscape are discussed.