Accurate information on the spatial distribution and temporal change of wetlands is vital to devise effective measures for their protection. This study uses satellite images in 1994 and 2001 to assess the effects of t...Accurate information on the spatial distribution and temporal change of wetlands is vital to devise effective measures for their protection. This study uses satellite images in 1994 and 2001 to assess the effects of topography and proximity to channels on wetland change in Maduo County on the Qinghai-Tibet Plateau, western China. In 1994 wetlands in the study area extended over 6,780.0 km2. They were distributed widely throughout the county, with a higher concentration in the south, and were especially prominent close to streams. The pattern of wetlands demonstrated a bell-shaped distribution curve with elevation, ranging over hill slopes with gradients from 0-19°, the commonest gradient being around 3°. Although the aspects of these hill slopes range over all directions, there is a lower concentration of wetlands facing east and southeast. The extent of wetlands in 2001 decreased to 6,181.1 km2. Marked spatial differentiation in the pattern of wetlands is evident, as their area increased by 1,193.3 km2 at lower elevations but decreased by 1,792.2 km2 at higher ground, resulting in a net decrease of 598.8 km2. In areas with a gradient <2° or >9° the area of wetlands remained approximately consistent from 1994-2001. Newly retained wetlands are situated in relatively flat lowland areas, with no evident preference in terms of aspect. Wetlands on north-, east- and northeast-facing hillslopes with a bearing of 1-86° were more prone to loss of area than other orientations. The altered pattern of wetland distribution from higher to lower elevation on north-facing slopes coincided with the doubling of annual temperature during the same period, suggesting that climate warming could be an important cause.展开更多
Abstract Phyllochaetopterus species are widely distributed on the coast of China. Here, Phyllochaetopterus hainanensis n. sp., a new species collected from Hainan Island (China), is reported. It is characterized by ...Abstract Phyllochaetopterus species are widely distributed on the coast of China. Here, Phyllochaetopterus hainanensis n. sp., a new species collected from Hainan Island (China), is reported. It is characterized by having a V-shaped peristomium, two eyespots covered by a pair of large curved peristomial notopodia (cirri located beneath the palps), 13-14 chaetigers in the anterior body region, with three enlarged modified chaetae on the fourth notopodium, and more than five chaetigers in the middle body region. The modified chaeta has a slightly inflated head with an obliquely truncate end. The new species resembles Phyllochaetopterus socialis Clapar6de, 1869, but differs in the shape of peristomial notopodia and peristomium. Twelve species of Phyllochaetopterus have been described from the Pacific Ocean, including the new species described here. An identification key to the known Pacific species is provided together with a brief discussion of the taxonomic value of the eyespots for the genus.展开更多
Based on the simulation with the Ocean-Atmosphere Coupled Model CCSM and Ocean Model POP under the green- house gas emission scenario of the IPCC SRES A2 (IPCC, 2001), and on the earth crust subsidence and glacier m...Based on the simulation with the Ocean-Atmosphere Coupled Model CCSM and Ocean Model POP under the green- house gas emission scenario of the IPCC SRES A2 (IPCC, 2001), and on the earth crust subsidence and glacier melting data, the relative sea level change is obtained along the coast of China in the 21 st century. Using the SRTM elevation data the submergence of coastal low land is calculated under the extreme water level with a 100-year retum period. The total flooding areas are 98.3× 10^3 and 104.9× 10^3 km2 for 2050 and 2080, respectively. For the three regions most vulnerable to extreme sea level rise, i.e., the coast of Bohai Bay, the Yangtze River Delta together with neighboring Jiangsu Province and northern Zhejiang Province, and the Pearl River Delta, the flooded areas are 5.0× 10^3, 64.1×10^3 and 15.3 × 10^3 km2 in 2050 and 5.2 × 10^3, 67.8×10^3 and 17.2 × 10^3 km2 in 2080, respectively.展开更多
An ocean reanalysis system for the joining area of Asia and Indian-Pacific Ocean (AIPO) has been developed and is currently delivering reanalysis data sets for study on the air-sea interaction over AIPO and its climat...An ocean reanalysis system for the joining area of Asia and Indian-Pacific Ocean (AIPO) has been developed and is currently delivering reanalysis data sets for study on the air-sea interaction over AIPO and its climate variation over China in the inter-annual time scale.This system consists of a nested ocean model forced by atmospheric reanalysis,an ensemble-based multivariate ocean data assimilation system and various ocean observations.The following report describes the main components of the data assimilation system in detail.The system adopts an ensemble optimal interpolation scheme that uses a seasonal update from a free running model to estimate the background error covariance matrix.In view of the systematic biases in some observation systems,some treatments were performed on the observations before the assimilation.A coarse resolution reanalysis dataset from the system is preliminarily evaluated to demonstrate the performance of the system for the period 1992 to 2006 by comparing this dataset with other observations or reanalysis data.展开更多
Dominant species of zooplankton community vary with latitude. Though China possesses a vast coastal area in northwestern Pacific, studies on the latitudinal dominant species gradient are rare. We collected zooplankton...Dominant species of zooplankton community vary with latitude. Though China possesses a vast coastal area in northwestern Pacific, studies on the latitudinal dominant species gradient are rare. We collected zooplankton samples from Haizhou Bay(34.56?–35.19?N, 119.51?–120.30?E), Yueqing Bay(28.14?–28.38?N, 121.10?–121.21?E) and Dongshan Bay(23.65?–23.90?N, 117.45?–117.60?E) in May 2012 and May 2013 to preliminarily characterize the latitudinal dominant species distribution. All the samples were collected vertically using a 0.505 mm mesh plankton net with 0.8 m in mouth diameter from bottom to surface. Calanus sinicus, Aidanosagitta crassa, Labidocera euchaeta, Zonosagitta nagae, Acartia pacifica and Paracalanus parvus were found to be dominant. C. sinicus was the most dominant species and the unique one occurred in all three bays. With latitude decreasing, both the abundance and proportion of C. sinicus declined sharply. Cluster analysis showed that the 6 dominant species could be divided into 3 groups, based on their occurrences in the three bays. Our results suggested that the distribution of dominant species along the coast of China has a significant latitudinal gradient. C. sinicus which widely distributes in the coastal water of the northwestern Pacific can well adapt to the temperature at different latitudes. The high abundance in Haizhou Bay indicated that C. sinicus was an exemplary warm-temperate species, and more commonly occurs in the north of China seas. The ecological characteristics of dominant species change from warm-temperate type in high-latitudinal bays to warm water type in low-latitudinal bays.展开更多
The skewness of subsurface temperature anomaly in the equatorial Pacific Ocean shows a significant asymmetry between the east and west. A positive temperature skewness appears in the equatorial eastern Pacific, while ...The skewness of subsurface temperature anomaly in the equatorial Pacific Ocean shows a significant asymmetry between the east and west. A positive temperature skewness appears in the equatorial eastern Pacific, while the temperature skewness in the western and central Pacific is primarily negative. There is also an asymmetry of the temperature skewness above and below the climatological mean therrnocline in the central and western Pacific. A positive skewness appears below the thermocline, but the skewness is negative above the thermocline. The distinctive vertical asymmetry of the temperature skewness is argued to be attributed to the asymmetric temperature response to upward and downward thermocline displacement in the presence of the observed upper-ocean vertical thermal structure. Because of positive (negative) second derivative of temperature with respect to depth below (above) the thermocline, an upward and a downward shift of the thermocline with equal displacement would lead to a negative temperature skewness above the thermocline but a positive skewness below the thermocline. In the far eastern equatorial Pacific, the thermocline is close to the base of the mixed layer, the shape of the upper-ocean vertical temperature profile cannot be kept. Positive skewness appears in both below the thermocline and above the thermocline in the far eastern basin. Over the central and eastern Pacific, the anomalies of the subsurface waters tend to entrain into the surface mixed layer (by climatological mean upwelling) and then affect the SST. Hence, the positive (negative) subsurface skewness in the far eastern (central) Pacific may favor positive (negative) SST skewness, which is consistent with the observational fact that more La Nina (EI Nino) occur in the central (eastern) Pacific. The present result implies a possible new paradigm for EI Nino and La Nina amplitude asymmetry in the eastern Pacific.展开更多
The variation of winter snowfall intensity over Northeast China and its relationship with the autumn North Pacific SST are investigated for the period 1960–2012. An upward trend is apparent for the winter snowfall in...The variation of winter snowfall intensity over Northeast China and its relationship with the autumn North Pacific SST are investigated for the period 1960–2012. An upward trend is apparent for the winter snowfall intensity over Northeast China during the last half-century, coinciding with an increasing autumn SST over the North Pacific. Their interannual correlation coefficient reaches up to 0.58 for the past five decades, and 0.42 after their trends are removed. Further analyses indicate that the warming SST during autumn may persist into winter. Correspondingly, large parts of East Asia and the North Pacific are dominated by an anticyclonic anomaly, which can induce an anomalous southeasterly over Northeast China, weaken the northerly wind, then warm the surface, increase the water vapor content and intensify snowfall events. Thus, the autumn North Pacific SST can be considered as a key predictor for winter snowfall events over Northeast China. Results from leaveone-out cross-validation and independent validation both show a significant correlation and a small RMSE between prediction and observation. Therefore, the autumn SST over the North Pacific is suggested as a potential predictor for winter snowfall intensity in Northeast China.展开更多
Trends in temperature and precipitation extremes from 1961 to 2008 have been investigated over Circum-Bohai-Sea region, China using daily temperature and precipitation data of 63 meteorological stations. The re- suits...Trends in temperature and precipitation extremes from 1961 to 2008 have been investigated over Circum-Bohai-Sea region, China using daily temperature and precipitation data of 63 meteorological stations. The re- suits show that at most stations, there is a significant increase in the annual frequency of warm days and warm nights, as well as a significant decrease in the annual frequency of cold days, cold nights, frost days, and annual diurnal tem- perature range (DTR). Their regional averaged changes are 2.06 d/1 0yr, 3.95 d/10yr, -1.88 d/10yr, -4.27 d/10yr, -4.21 d/10yr and -0.20℃/10yr, respectively. Seasonal changes display similar patterns to the annual results, but there is a large seasonal difference. A significant warming trend is detected at both annual and seasonal scales, which is more contributed by changes of indices defined by daily minimum temperature than those defined by daily maximum tem- perature. For precipitation indices, the regional annual extreme precipitation displays a weak decrease in terms of magnitude and frequency, i.e. extreme precipitation days (RD95p), intensity (RINTEN), proportion (RPROP) and maximum consecutive wet days (CWD), but a slight increase in the maximum consecutive dry days (CDD), which are consistent with changes of annual total precipitation (PRCPTOT). Seasonally, PRCPTOT and RD95p both exhibit an increase in spring and a decrease in other seasons with the largest decrease in summer, but generally not significant. In summary, this study shows a pronounced warming tendency at the less rainy period over Circum-Bohai-Sea region, which may affect regional economic development and ecological protection to some extent.展开更多
Collaboration of interannual variabilities and the climate mean state determines the type of E1 Nifio. Recent studies highlight the impact of a La Nifia-like mean state change, which acts to suppress the convection an...Collaboration of interannual variabilities and the climate mean state determines the type of E1 Nifio. Recent studies highlight the impact of a La Nifia-like mean state change, which acts to suppress the convection and low-level convergence over the central Pacific, on the predominance of central Pacific (CP) E1 Nifio in the most recent decade. However, how interannual variabilities affect the climate mean state has been less thoroughly investigated. Using a linear shallow-water model, the ef- fect of decadal changes of air-sea interaction on the two types of El Nifio and the climate mean state over the tropical Pacific is examined. It is demonstrated that the predominance of the eastem Pacific (EP) and CP E1 Nino is dominated mainly by relationships between anomalous wind stresses and sea surface temperature (SST). Furthermore, changes between air-sea interactions from 1980-98 to 1999-2011 prompted the generation of the La Ninalike pattern, which is similar to the background change in the most recent decade.展开更多
This paper probes into the feasibility of equilibrating pressure of water distribution network through (using auto-control valves) in theory and in the economy. An optimal valve control model is designed to minimize t...This paper probes into the feasibility of equilibrating pressure of water distribution network through (using auto-control valves) in theory and in the economy. An optimal valve control model is designed to minimize the sum of squares of residual pressure in the network. Such an analog simulation has been performed on the year 2003 programming network of a certain littoral district in North China, through which this paper confirms that it is feasible to equilibrate pressure with auto-control valves in theory. The research work has brought about a discovery of applicable conditions of valves in economic feasibility, which avoids a great economic loss due to the wild use of auto-control valve. In addition, simulated annealing algorithm is applied to optimize valve settings and shown to identify global optimum or near-optimum.展开更多
A typhoon-induced storm surge simulation system was developed for the Qingdao area, including a typhoon diagnostic model for the generation of wind and pressure fields and a 2D Advanced Circulation(ADCIRC) model for s...A typhoon-induced storm surge simulation system was developed for the Qingdao area, including a typhoon diagnostic model for the generation of wind and pressure fields and a 2D Advanced Circulation(ADCIRC) model for simulating the associated storm surge with a 200 m resolution along the Qingdao coastline. The system was validated by an extreme surge event Typhoon Mamie(8509) and the parameters of Typhoon Mamie were used to investigate the sensitivity of typhoon paths to Qingdao storm surges with four selected paths: the paths of Typhoons Mamie(8509), Opal, 3921 and 2413, the selection being made according to their relative position to Qingdao. Experiments based on the Typhoon Mamie(8509) storm surge were also conducted to study the possible influences of future climate changes, including the sea level rise and sea surface temperature(SST) rise, on storm surges along the Qingdao coast. Storm surge conditions under both present day and future(the end of the 21 st century) climate scenarios associated with the four selected paths were simulated. The results show that with the same intensity, when typhoons follow the paths of 3921 and 2413, they would lead to the most serious disasters in different areas of Qingdao. Sea level and SST affect storm surges in different ways: sea level rise affects storm surge mainly through its influence on the tide amplitude, while the increased SST has direct impact on the intensity of the surges. The possible maximum risk of storm surges in 2100 in the Qingdao area caused by typhoons like Mamie(8509) was also estimated in this study.展开更多
The CVI (coastal vulnerability index) was developed and used to assess the vulnerability of the coastline of the Kingdom of Bahrain main islands to future SLR (sea level rise). A total of 717 km of the coastline w...The CVI (coastal vulnerability index) was developed and used to assess the vulnerability of the coastline of the Kingdom of Bahrain main islands to future SLR (sea level rise). A total of 717 km of the coastline was evaluated. Six spatial factors acting on the coastal area: erosion/accretion patterns (shoreline change), topography (elevation above mean sea level), geology, geomorphology, slope, and mean sea level rise were incorporated and ranked to develop the CVI. This index was classified into four levels of vulnerability: low, moderate, high, and very high. Vulnerable hotspots are located along the central portions of the western and eastern coastlines. The vulnerability of these areas is mostly driven by their characteristically shallow coastal slopes, low elevations, and erosion-prone nature of the sandy soils presents, comprising about 54 km of the studied shoreline. Another 33 km of coastline were classified as highly vulnerable and located along the eastern coast. In addition, the western coast of the southern tip of the main island (Bahrain) was also classified as a highly vulnerable shoreline. Twenty-two km was classified as the moderate vulnerable. The remaining coastal areas were classified as low to moderately vulnerable comprising about 608 km of the total length of the coastline. Identifying those hotspots susceptible to SLR is essential for more effective coastal zone management and to help in reducing the impacts of SLR on both infrastructure and human beings.展开更多
Tidal data from Weizhou, Zhapo, and Shanwei stations between 1969 and 2010 and from five gauging stations in the western Pacific Ocean provided by PSMSL, and the global mean sea level data recorded between December 19...Tidal data from Weizhou, Zhapo, and Shanwei stations between 1969 and 2010 and from five gauging stations in the western Pacific Ocean provided by PSMSL, and the global mean sea level data recorded between December 1992 and December 2010 by TOPEX and Jason satellites were compiled and analyzed. The results show that the perennial mean sea level near Weizhou Island is 211.7 cm(relative to the water gauge zero), and the relative mean sea level rising rate is 2.2 mm yr-1 from 1969 to 2010, which is consistent with the relative mean sea level rising rate recorded at other gauging stations in the western Pacific regions and with the global mean sea level rising rate. The absolute mean sea level rising rate at Weizhou Island is 3.0 mm yr-1 from 1993 to 2010, also conforming with the global mean sea level rising rate(3.1±0.4 mm yr-1) during the same time period. The highest annual tide level at Weizhou Island has a rising rate of 4.6 mm yr-1 and shows a 20-year quasi-periodic variation from 1966 to 2010. The primary cause of the mean sea level rising is global warming.展开更多
This paper analyzes the seismicity and seismic risk distribution in the Bohai Sea. Based on the seismic design parameters of 46 platforms in the Bohai Sea, a statistic analysis is made on the ratios of the peak accele...This paper analyzes the seismicity and seismic risk distribution in the Bohai Sea. Based on the seismic design parameters of 46 platforms in the Bohai Sea, a statistic analysis is made on the ratios of the peak accelerations for different probability levels. In accordance with the two-stage design method, a scheme of two design seismic levels is proposed, and two fortification goals are established respectively for strength level earthquakes and ductility level earthquakes. Through analogy and comparison to the Chinese seismic code for buildings, it is proposed that the probability level for the strength and ductility level earthquakes takes return periods of 200a and 1000~2500a respectively, and we further expounded on its rationality. Finally, the fortification parameters in the sub-regions of Bohai Sea area are given in the light of seismic risk zonation and ground motion division. This article is a summary of experiences from many years of offshore platform seismic fortification work, and an exploratory study on the seismic fortification standards of offshore platforms in China, which may provide some references for the establishment of the standard.展开更多
We studied the impact of sea surface temperature anomaly(SSTA) in the Japan Sea and the sea area east of Japan on the winter rainfall and air temperature in Northeast(NE) China using the singular value decomposition(S...We studied the impact of sea surface temperature anomaly(SSTA) in the Japan Sea and the sea area east of Japan on the winter rainfall and air temperature in Northeast(NE) China using the singular value decomposition(SVD) and empirical orthogonal function(EOF). The monthly-mean rainfall data observed at 160 stations in China, monthly-mean sea surface temperature(SST) of the Hadley Center for Climate Prediction and Research and monthly-mean air temperature from the NCEP reanalysis during 1960–2011 were used. Correlation analysis indicates that the SSTAs in the Japan Sea in September may last for three or four months and are an important index for forecasting the winter rainfall and air temperature in NE China. Positive SSTAs in the central Japan Sea and in the sea area east of Tokyo correspond to positive rainfall anomaly and negative air temperature anomaly in NE China. With the rise of SST in the Japan Sea, a weak cyclone appears over the Japan Sea. The northeasterly wind transports water vapor from the Okhotsk to NE China, resulting in more rainfall and lower air temperature. Negative SSTA years are accompanied by warmer air temperature and less snow in NE China. The 1000 h Pa geopotential height anomaly and wind anomaly fields are simulated by IAP-9L model, which supports the analysis results.展开更多
The sea level derived from TOPEX/Poseidon (T/P) altimetry data shows prominent long term trend and inter-annual variability. The global mean sea level rising rate during 1993-2003 was 2.9mm a^-1. The T/P sea level t...The sea level derived from TOPEX/Poseidon (T/P) altimetry data shows prominent long term trend and inter-annual variability. The global mean sea level rising rate during 1993-2003 was 2.9mm a^-1. The T/P sea level trend maps the geographical variability. In the Northern Hemisphere (15°-64°N), the sea level rise is very fast at the mid-latitude (20°-40°N) but much slower at the high-latitude, for example, only 0.5 mm a^-1 in the latitude band 40°-50°N. In the Southern Hemisphere, the sea level shows high rising rate both in mid-latitude and high-latitude areas, for example, 5.1 mm a^-1 in the band 40°- 50°S. The global thermosteric sea level (TSL) derived from Ishii temperature data was rising during 1993-2003 at a rate of 1.2 mm a^-1 and accounted for more than 40% of the global T/P sea level rise. The contributions of the TSL distribution are not spatially uniform; for instance, the percentage is 67% for the Northern Hemisphere and only 29% for the Southern Hemisphere (15°-64°S) and the maximum thermosteric contribution appears in the Pacific Ocean, which contributes more than 60% of the global TSL. The sea level change trend in tropical ocean is mainly caused by the thermosteric effect, which is different from the case of seasonal variability in this area. The TSL variability dominates the T/P sea level rise in the North Atlantic, but it is small in other areas, and shows negative trend at the high-latitude area (40°-60°N, and 50°-60°S). The global TSL during 1945-2003 showed obvious rising trend with the rate of about 0.3 mm a-l and striking inter-annual and decadal variability with period of 20 years. In the past 60 years, the Atlantic TSL was rising continuously and remarkably, contributing 38% to the global TSL rising. The TSL in the Pacific and Indian Ocean rose with significant in- ter-annual and decadal variability. The first EOF mode of the global TSL from Ishii temperature data was the ENSO mode in which the time series of the first mode showed steady rising trend. Among the three oceans, the first mode of the Pacific TSL presented the ENSO mode; there was relatively steady rising trend in the Atlantic Ocean, and no dominant mode in the Indian Ocean.展开更多
Dew and fog play major roles in providing the atmospheric moisture for plants and arthropods living in arid regions all over the world. Studies are needed to discriminate between dew and fog. A radiation system was de...Dew and fog play major roles in providing the atmospheric moisture for plants and arthropods living in arid regions all over the world. Studies are needed to discriminate between dew and fog. A radiation system was developed for measuring the incoming and outgoing solar (shortwave) radiation using two CM21 Kipp & Zonen pyranometers (one inverted), and the incoming (atmospheric) and outgoing (terrestrial) longwave radiation using two CG1 pyrgeometers in Logan (41047' N, 111~51' W, 1,460 m above mean sea level), Utah, USA, continuously since 1995. These instruments are ventilated with heated air to prevent precipitation of dew and frost on the sensors, which otherwise would disturb the measurements. Based upon these measurements and an algorithm, the cloud base height, the cloud base temperature and percent of cloudiness can be parameterized at local scale. A cloud base height around zero would indicate fog at the local scale. In 1999, Bowen ratio system was added to measure the evapotranspiration, dew and frost continuously throughout the year at the same location close to the radiation system. Combining these two systems (radiation and Bowen ratio) has yielded a reasonable approach to differentiate between the atmospheric moistures collected by dew and fog.展开更多
On the Pacific coast of Russia implementation of the methodology of the integrated nature management has a number of peculiarities. On the one hand, these districts are characterized by severe hydrometeorological cond...On the Pacific coast of Russia implementation of the methodology of the integrated nature management has a number of peculiarities. On the one hand, these districts are characterized by severe hydrometeorological conditions. On the other hand, Russia has no applicable legislation on coastal issues. Thus, to prepare informational, theoretical and methodical bases for organization of sustained nature management in coastal zones of the Russian Federation, we developed hierarchy structure of delimitation of coastal areas and recommendations for their development on the basis of nature resource and social-economic zoning. Zoning of the Russian Far East is suggested to include two major directions: (1) planning of sustainable development of the region and (2) solving contradictions between fisheries and productions of oil and gas in the coastal zones.展开更多
Tsunamis in Mexico are a real threat, still unknown to many, mainly by people living in or visiting the coast. The Tsunami Warning Center in Mexico recently created (September 19, 2011) monitors earthquakes and sea ...Tsunamis in Mexico are a real threat, still unknown to many, mainly by people living in or visiting the coast. The Tsunami Warning Center in Mexico recently created (September 19, 2011) monitors earthquakes and sea level change caused by these same. Sea level on the west coast of the Mexican Pacific was analyzed after the occurrence of local, regional and distant earthquakes, in order to determine the existence of an anomaly due to the quake itself. Variations in sea level due to local registered earthquakes Mw 6.0 to 7.4 range was from 0.10 to 0.30 m; for regional earthquakes of Mw 7.3 and 8.2 were 0.12 and 0.22 m respectively and to the distant earthquake of Mw 8.0 recorded in Solomon Islands, the change in sea level of the maximum recorded was 0.20 m in Manzanillo, Colima. It is important to know that earthquakes whether local, regional or distant whose magnitudes are in the range specified here, did not present a risk to the Mexican coast, but do not rely, having to monitor variations in sea level that earthquakes can produce and be aware that you may perhaps occur as a tsunami in Indonesia in 2004 or Japan in 2011.展开更多
基金supported by the International Science & Technology Cooperation Program of China (Grant No. 2011DFG93160,2011DFA20820)the National Natural Sciences Foundation of China (Grant No.41161084)the Scientific Research Collaboration and Training of Top Scientists project (Document No. 2009-1599),Department of International Exchange & Cooperation of the Chinese Ministry of Education
文摘Accurate information on the spatial distribution and temporal change of wetlands is vital to devise effective measures for their protection. This study uses satellite images in 1994 and 2001 to assess the effects of topography and proximity to channels on wetland change in Maduo County on the Qinghai-Tibet Plateau, western China. In 1994 wetlands in the study area extended over 6,780.0 km2. They were distributed widely throughout the county, with a higher concentration in the south, and were especially prominent close to streams. The pattern of wetlands demonstrated a bell-shaped distribution curve with elevation, ranging over hill slopes with gradients from 0-19°, the commonest gradient being around 3°. Although the aspects of these hill slopes range over all directions, there is a lower concentration of wetlands facing east and southeast. The extent of wetlands in 2001 decreased to 6,181.1 km2. Marked spatial differentiation in the pattern of wetlands is evident, as their area increased by 1,193.3 km2 at lower elevations but decreased by 1,792.2 km2 at higher ground, resulting in a net decrease of 598.8 km2. In areas with a gradient <2° or >9° the area of wetlands remained approximately consistent from 1994-2001. Newly retained wetlands are situated in relatively flat lowland areas, with no evident preference in terms of aspect. Wetlands on north-, east- and northeast-facing hillslopes with a bearing of 1-86° were more prone to loss of area than other orientations. The altered pattern of wetland distribution from higher to lower elevation on north-facing slopes coincided with the doubling of annual temperature during the same period, suggesting that climate warming could be an important cause.
基金Supported by the Ocean Public Welfare Scientific Research Project(No.201105012)
文摘Abstract Phyllochaetopterus species are widely distributed on the coast of China. Here, Phyllochaetopterus hainanensis n. sp., a new species collected from Hainan Island (China), is reported. It is characterized by having a V-shaped peristomium, two eyespots covered by a pair of large curved peristomial notopodia (cirri located beneath the palps), 13-14 chaetigers in the anterior body region, with three enlarged modified chaetae on the fourth notopodium, and more than five chaetigers in the middle body region. The modified chaeta has a slightly inflated head with an obliquely truncate end. The new species resembles Phyllochaetopterus socialis Clapar6de, 1869, but differs in the shape of peristomial notopodia and peristomium. Twelve species of Phyllochaetopterus have been described from the Pacific Ocean, including the new species described here. An identification key to the known Pacific species is provided together with a brief discussion of the taxonomic value of the eyespots for the genus.
基金supported by the National Key Technology R&D Program(No.2007BAC03A06)the National Natural Science Foundation of China(NSFC)project(No.40976006)+2 种基金the National Marine Public Welfare Research Project of China(No.201005019)Key Laboratory Project(Key Laboratory of Coastal Disasters and Defence,Ministry of Education,No.200808)Laboratory of Coastal Disasters and Defence,Ministry of Education)(No.200802)
文摘Based on the simulation with the Ocean-Atmosphere Coupled Model CCSM and Ocean Model POP under the green- house gas emission scenario of the IPCC SRES A2 (IPCC, 2001), and on the earth crust subsidence and glacier melting data, the relative sea level change is obtained along the coast of China in the 21 st century. Using the SRTM elevation data the submergence of coastal low land is calculated under the extreme water level with a 100-year retum period. The total flooding areas are 98.3× 10^3 and 104.9× 10^3 km2 for 2050 and 2080, respectively. For the three regions most vulnerable to extreme sea level rise, i.e., the coast of Bohai Bay, the Yangtze River Delta together with neighboring Jiangsu Province and northern Zhejiang Province, and the Pearl River Delta, the flooded areas are 5.0× 10^3, 64.1×10^3 and 15.3 × 10^3 km2 in 2050 and 5.2 × 10^3, 67.8×10^3 and 17.2 × 10^3 km2 in 2080, respectively.
基金supported by the Chinese Academy of Sciences (Grant No. KZCX2-YW-202)the 973 Pro-gram (Grant No. 2006CB403606),the 863 Program (Grant No.2009AA12Z138)the National Natural Science Foundation of China (Grant Nos. 40606008,40437017,and 40221503)
文摘An ocean reanalysis system for the joining area of Asia and Indian-Pacific Ocean (AIPO) has been developed and is currently delivering reanalysis data sets for study on the air-sea interaction over AIPO and its climate variation over China in the inter-annual time scale.This system consists of a nested ocean model forced by atmospheric reanalysis,an ensemble-based multivariate ocean data assimilation system and various ocean observations.The following report describes the main components of the data assimilation system in detail.The system adopts an ensemble optimal interpolation scheme that uses a seasonal update from a free running model to estimate the background error covariance matrix.In view of the systematic biases in some observation systems,some treatments were performed on the observations before the assimilation.A coarse resolution reanalysis dataset from the system is preliminarily evaluated to demonstrate the performance of the system for the period 1992 to 2006 by comparing this dataset with other observations or reanalysis data.
基金funded by the National Natural Science Foundation of China (No. 41176131)the National Special Research Fund for Non-Profit Marine Sector (No. 201305027-8)
文摘Dominant species of zooplankton community vary with latitude. Though China possesses a vast coastal area in northwestern Pacific, studies on the latitudinal dominant species gradient are rare. We collected zooplankton samples from Haizhou Bay(34.56?–35.19?N, 119.51?–120.30?E), Yueqing Bay(28.14?–28.38?N, 121.10?–121.21?E) and Dongshan Bay(23.65?–23.90?N, 117.45?–117.60?E) in May 2012 and May 2013 to preliminarily characterize the latitudinal dominant species distribution. All the samples were collected vertically using a 0.505 mm mesh plankton net with 0.8 m in mouth diameter from bottom to surface. Calanus sinicus, Aidanosagitta crassa, Labidocera euchaeta, Zonosagitta nagae, Acartia pacifica and Paracalanus parvus were found to be dominant. C. sinicus was the most dominant species and the unique one occurred in all three bays. With latitude decreasing, both the abundance and proportion of C. sinicus declined sharply. Cluster analysis showed that the 6 dominant species could be divided into 3 groups, based on their occurrences in the three bays. Our results suggested that the distribution of dominant species along the coast of China has a significant latitudinal gradient. C. sinicus which widely distributes in the coastal water of the northwestern Pacific can well adapt to the temperature at different latitudes. The high abundance in Haizhou Bay indicated that C. sinicus was an exemplary warm-temperate species, and more commonly occurs in the north of China seas. The ecological characteristics of dominant species change from warm-temperate type in high-latitudinal bays to warm water type in low-latitudinal bays.
基金Supported by the National Basic Research Program of China (973 Program)(No 2007CB816005)the National Natural Science Foundation of China (No 40706003)+1 种基金International S&T Cooperation Project of the Ministry of Science and Technology of China (No2009DFA21430)the COPES in China (GYHY200706005)
文摘The skewness of subsurface temperature anomaly in the equatorial Pacific Ocean shows a significant asymmetry between the east and west. A positive temperature skewness appears in the equatorial eastern Pacific, while the temperature skewness in the western and central Pacific is primarily negative. There is also an asymmetry of the temperature skewness above and below the climatological mean therrnocline in the central and western Pacific. A positive skewness appears below the thermocline, but the skewness is negative above the thermocline. The distinctive vertical asymmetry of the temperature skewness is argued to be attributed to the asymmetric temperature response to upward and downward thermocline displacement in the presence of the observed upper-ocean vertical thermal structure. Because of positive (negative) second derivative of temperature with respect to depth below (above) the thermocline, an upward and a downward shift of the thermocline with equal displacement would lead to a negative temperature skewness above the thermocline but a positive skewness below the thermocline. In the far eastern equatorial Pacific, the thermocline is close to the base of the mixed layer, the shape of the upper-ocean vertical temperature profile cannot be kept. Positive skewness appears in both below the thermocline and above the thermocline in the far eastern basin. Over the central and eastern Pacific, the anomalies of the subsurface waters tend to entrain into the surface mixed layer (by climatological mean upwelling) and then affect the SST. Hence, the positive (negative) subsurface skewness in the far eastern (central) Pacific may favor positive (negative) SST skewness, which is consistent with the observational fact that more La Nina (EI Nino) occur in the central (eastern) Pacific. The present result implies a possible new paradigm for EI Nino and La Nina amplitude asymmetry in the eastern Pacific.
基金jointly supported by the National Basic Research Program of China[grant number 2012CB955401]National Natural Science Foundation of China[grant numbers 41305061 and 41210007]
文摘The variation of winter snowfall intensity over Northeast China and its relationship with the autumn North Pacific SST are investigated for the period 1960–2012. An upward trend is apparent for the winter snowfall intensity over Northeast China during the last half-century, coinciding with an increasing autumn SST over the North Pacific. Their interannual correlation coefficient reaches up to 0.58 for the past five decades, and 0.42 after their trends are removed. Further analyses indicate that the warming SST during autumn may persist into winter. Correspondingly, large parts of East Asia and the North Pacific are dominated by an anticyclonic anomaly, which can induce an anomalous southeasterly over Northeast China, weaken the northerly wind, then warm the surface, increase the water vapor content and intensify snowfall events. Thus, the autumn North Pacific SST can be considered as a key predictor for winter snowfall events over Northeast China. Results from leaveone-out cross-validation and independent validation both show a significant correlation and a small RMSE between prediction and observation. Therefore, the autumn SST over the North Pacific is suggested as a potential predictor for winter snowfall intensity in Northeast China.
基金Under the auspices of National Natural Science Foundation of China (No.40901028)
文摘Trends in temperature and precipitation extremes from 1961 to 2008 have been investigated over Circum-Bohai-Sea region, China using daily temperature and precipitation data of 63 meteorological stations. The re- suits show that at most stations, there is a significant increase in the annual frequency of warm days and warm nights, as well as a significant decrease in the annual frequency of cold days, cold nights, frost days, and annual diurnal tem- perature range (DTR). Their regional averaged changes are 2.06 d/1 0yr, 3.95 d/10yr, -1.88 d/10yr, -4.27 d/10yr, -4.21 d/10yr and -0.20℃/10yr, respectively. Seasonal changes display similar patterns to the annual results, but there is a large seasonal difference. A significant warming trend is detected at both annual and seasonal scales, which is more contributed by changes of indices defined by daily minimum temperature than those defined by daily maximum tem- perature. For precipitation indices, the regional annual extreme precipitation displays a weak decrease in terms of magnitude and frequency, i.e. extreme precipitation days (RD95p), intensity (RINTEN), proportion (RPROP) and maximum consecutive wet days (CWD), but a slight increase in the maximum consecutive dry days (CDD), which are consistent with changes of annual total precipitation (PRCPTOT). Seasonally, PRCPTOT and RD95p both exhibit an increase in spring and a decrease in other seasons with the largest decrease in summer, but generally not significant. In summary, this study shows a pronounced warming tendency at the less rainy period over Circum-Bohai-Sea region, which may affect regional economic development and ecological protection to some extent.
基金supported by the National Program for Support of Top-notch Young Professionals,the National Basic Research Program of China (Grant Nos. 2012CB955202 and 2012CB417404)"Western Pacific Ocean System: Structure, Dynamics, and Consequences" of the Chinese Academy Sciences (WPOS+1 种基金 Grant No. XDA10010405)the National Natural Science Foundation of China (Grant No. 41176014)
文摘Collaboration of interannual variabilities and the climate mean state determines the type of E1 Nifio. Recent studies highlight the impact of a La Nifia-like mean state change, which acts to suppress the convection and low-level convergence over the central Pacific, on the predominance of central Pacific (CP) E1 Nifio in the most recent decade. However, how interannual variabilities affect the climate mean state has been less thoroughly investigated. Using a linear shallow-water model, the ef- fect of decadal changes of air-sea interaction on the two types of El Nifio and the climate mean state over the tropical Pacific is examined. It is demonstrated that the predominance of the eastem Pacific (EP) and CP E1 Nino is dominated mainly by relationships between anomalous wind stresses and sea surface temperature (SST). Furthermore, changes between air-sea interactions from 1980-98 to 1999-2011 prompted the generation of the La Ninalike pattern, which is similar to the background change in the most recent decade.
文摘This paper probes into the feasibility of equilibrating pressure of water distribution network through (using auto-control valves) in theory and in the economy. An optimal valve control model is designed to minimize the sum of squares of residual pressure in the network. Such an analog simulation has been performed on the year 2003 programming network of a certain littoral district in North China, through which this paper confirms that it is feasible to equilibrate pressure with auto-control valves in theory. The research work has brought about a discovery of applicable conditions of valves in economic feasibility, which avoids a great economic loss due to the wild use of auto-control valve. In addition, simulated annealing algorithm is applied to optimize valve settings and shown to identify global optimum or near-optimum.
基金supported by the Marine Industry Research Special Funds for Public Welfare Projects (No. 200905013)
文摘A typhoon-induced storm surge simulation system was developed for the Qingdao area, including a typhoon diagnostic model for the generation of wind and pressure fields and a 2D Advanced Circulation(ADCIRC) model for simulating the associated storm surge with a 200 m resolution along the Qingdao coastline. The system was validated by an extreme surge event Typhoon Mamie(8509) and the parameters of Typhoon Mamie were used to investigate the sensitivity of typhoon paths to Qingdao storm surges with four selected paths: the paths of Typhoons Mamie(8509), Opal, 3921 and 2413, the selection being made according to their relative position to Qingdao. Experiments based on the Typhoon Mamie(8509) storm surge were also conducted to study the possible influences of future climate changes, including the sea level rise and sea surface temperature(SST) rise, on storm surges along the Qingdao coast. Storm surge conditions under both present day and future(the end of the 21 st century) climate scenarios associated with the four selected paths were simulated. The results show that with the same intensity, when typhoons follow the paths of 3921 and 2413, they would lead to the most serious disasters in different areas of Qingdao. Sea level and SST affect storm surges in different ways: sea level rise affects storm surge mainly through its influence on the tide amplitude, while the increased SST has direct impact on the intensity of the surges. The possible maximum risk of storm surges in 2100 in the Qingdao area caused by typhoons like Mamie(8509) was also estimated in this study.
文摘The CVI (coastal vulnerability index) was developed and used to assess the vulnerability of the coastline of the Kingdom of Bahrain main islands to future SLR (sea level rise). A total of 717 km of the coastline was evaluated. Six spatial factors acting on the coastal area: erosion/accretion patterns (shoreline change), topography (elevation above mean sea level), geology, geomorphology, slope, and mean sea level rise were incorporated and ranked to develop the CVI. This index was classified into four levels of vulnerability: low, moderate, high, and very high. Vulnerable hotspots are located along the central portions of the western and eastern coastlines. The vulnerability of these areas is mostly driven by their characteristically shallow coastal slopes, low elevations, and erosion-prone nature of the sandy soils presents, comprising about 54 km of the studied shoreline. Another 33 km of coastline were classified as highly vulnerable and located along the eastern coast. In addition, the western coast of the southern tip of the main island (Bahrain) was also classified as a highly vulnerable shoreline. Twenty-two km was classified as the moderate vulnerable. The remaining coastal areas were classified as low to moderately vulnerable comprising about 608 km of the total length of the coastline. Identifying those hotspots susceptible to SLR is essential for more effective coastal zone management and to help in reducing the impacts of SLR on both infrastructure and human beings.
基金supported by the Youth Ocean Science Foundation of SOA, China (2010208)the National Natural Science Foundation of China (41030856)
文摘Tidal data from Weizhou, Zhapo, and Shanwei stations between 1969 and 2010 and from five gauging stations in the western Pacific Ocean provided by PSMSL, and the global mean sea level data recorded between December 1992 and December 2010 by TOPEX and Jason satellites were compiled and analyzed. The results show that the perennial mean sea level near Weizhou Island is 211.7 cm(relative to the water gauge zero), and the relative mean sea level rising rate is 2.2 mm yr-1 from 1969 to 2010, which is consistent with the relative mean sea level rising rate recorded at other gauging stations in the western Pacific regions and with the global mean sea level rising rate. The absolute mean sea level rising rate at Weizhou Island is 3.0 mm yr-1 from 1993 to 2010, also conforming with the global mean sea level rising rate(3.1±0.4 mm yr-1) during the same time period. The highest annual tide level at Weizhou Island has a rising rate of 4.6 mm yr-1 and shows a 20-year quasi-periodic variation from 1966 to 2010. The primary cause of the mean sea level rising is global warming.
基金Supported by Special Scientific Research of Public Welfare Profession of Ministry of Finance,the People's Republic of China(200708055)
文摘This paper analyzes the seismicity and seismic risk distribution in the Bohai Sea. Based on the seismic design parameters of 46 platforms in the Bohai Sea, a statistic analysis is made on the ratios of the peak accelerations for different probability levels. In accordance with the two-stage design method, a scheme of two design seismic levels is proposed, and two fortification goals are established respectively for strength level earthquakes and ductility level earthquakes. Through analogy and comparison to the Chinese seismic code for buildings, it is proposed that the probability level for the strength and ductility level earthquakes takes return periods of 200a and 1000~2500a respectively, and we further expounded on its rationality. Finally, the fortification parameters in the sub-regions of Bohai Sea area are given in the light of seismic risk zonation and ground motion division. This article is a summary of experiences from many years of offshore platform seismic fortification work, and an exploratory study on the seismic fortification standards of offshore platforms in China, which may provide some references for the establishment of the standard.
基金supported by Innovation and Research Foundation of Ocean University of China(No.201261009)the National Natural Science Foundation of China(Nos.40930844 and 10735030)the National Basic Research Program of China(the 973 Program)under grant No.2005CB422 301
文摘We studied the impact of sea surface temperature anomaly(SSTA) in the Japan Sea and the sea area east of Japan on the winter rainfall and air temperature in Northeast(NE) China using the singular value decomposition(SVD) and empirical orthogonal function(EOF). The monthly-mean rainfall data observed at 160 stations in China, monthly-mean sea surface temperature(SST) of the Hadley Center for Climate Prediction and Research and monthly-mean air temperature from the NCEP reanalysis during 1960–2011 were used. Correlation analysis indicates that the SSTAs in the Japan Sea in September may last for three or four months and are an important index for forecasting the winter rainfall and air temperature in NE China. Positive SSTAs in the central Japan Sea and in the sea area east of Tokyo correspond to positive rainfall anomaly and negative air temperature anomaly in NE China. With the rise of SST in the Japan Sea, a weak cyclone appears over the Japan Sea. The northeasterly wind transports water vapor from the Okhotsk to NE China, resulting in more rainfall and lower air temperature. Negative SSTA years are accompanied by warmer air temperature and less snow in NE China. The 1000 h Pa geopotential height anomaly and wind anomaly fields are simulated by IAP-9L model, which supports the analysis results.
基金supported by the National Basic Research Program of China (No 2007CB411807)the NSFC project (Nos 40976006 and 40906002)+1 种基金the National Key Technology R&D Program (No 2007BAC03A06-06)the project of Key Laboratory of Coastal Disasters and Defence (No 200802)
文摘The sea level derived from TOPEX/Poseidon (T/P) altimetry data shows prominent long term trend and inter-annual variability. The global mean sea level rising rate during 1993-2003 was 2.9mm a^-1. The T/P sea level trend maps the geographical variability. In the Northern Hemisphere (15°-64°N), the sea level rise is very fast at the mid-latitude (20°-40°N) but much slower at the high-latitude, for example, only 0.5 mm a^-1 in the latitude band 40°-50°N. In the Southern Hemisphere, the sea level shows high rising rate both in mid-latitude and high-latitude areas, for example, 5.1 mm a^-1 in the band 40°- 50°S. The global thermosteric sea level (TSL) derived from Ishii temperature data was rising during 1993-2003 at a rate of 1.2 mm a^-1 and accounted for more than 40% of the global T/P sea level rise. The contributions of the TSL distribution are not spatially uniform; for instance, the percentage is 67% for the Northern Hemisphere and only 29% for the Southern Hemisphere (15°-64°S) and the maximum thermosteric contribution appears in the Pacific Ocean, which contributes more than 60% of the global TSL. The sea level change trend in tropical ocean is mainly caused by the thermosteric effect, which is different from the case of seasonal variability in this area. The TSL variability dominates the T/P sea level rise in the North Atlantic, but it is small in other areas, and shows negative trend at the high-latitude area (40°-60°N, and 50°-60°S). The global TSL during 1945-2003 showed obvious rising trend with the rate of about 0.3 mm a-l and striking inter-annual and decadal variability with period of 20 years. In the past 60 years, the Atlantic TSL was rising continuously and remarkably, contributing 38% to the global TSL rising. The TSL in the Pacific and Indian Ocean rose with significant in- ter-annual and decadal variability. The first EOF mode of the global TSL from Ishii temperature data was the ENSO mode in which the time series of the first mode showed steady rising trend. Among the three oceans, the first mode of the Pacific TSL presented the ENSO mode; there was relatively steady rising trend in the Atlantic Ocean, and no dominant mode in the Indian Ocean.
文摘Dew and fog play major roles in providing the atmospheric moisture for plants and arthropods living in arid regions all over the world. Studies are needed to discriminate between dew and fog. A radiation system was developed for measuring the incoming and outgoing solar (shortwave) radiation using two CM21 Kipp & Zonen pyranometers (one inverted), and the incoming (atmospheric) and outgoing (terrestrial) longwave radiation using two CG1 pyrgeometers in Logan (41047' N, 111~51' W, 1,460 m above mean sea level), Utah, USA, continuously since 1995. These instruments are ventilated with heated air to prevent precipitation of dew and frost on the sensors, which otherwise would disturb the measurements. Based upon these measurements and an algorithm, the cloud base height, the cloud base temperature and percent of cloudiness can be parameterized at local scale. A cloud base height around zero would indicate fog at the local scale. In 1999, Bowen ratio system was added to measure the evapotranspiration, dew and frost continuously throughout the year at the same location close to the radiation system. Combining these two systems (radiation and Bowen ratio) has yielded a reasonable approach to differentiate between the atmospheric moistures collected by dew and fog.
文摘On the Pacific coast of Russia implementation of the methodology of the integrated nature management has a number of peculiarities. On the one hand, these districts are characterized by severe hydrometeorological conditions. On the other hand, Russia has no applicable legislation on coastal issues. Thus, to prepare informational, theoretical and methodical bases for organization of sustained nature management in coastal zones of the Russian Federation, we developed hierarchy structure of delimitation of coastal areas and recommendations for their development on the basis of nature resource and social-economic zoning. Zoning of the Russian Far East is suggested to include two major directions: (1) planning of sustainable development of the region and (2) solving contradictions between fisheries and productions of oil and gas in the coastal zones.
文摘Tsunamis in Mexico are a real threat, still unknown to many, mainly by people living in or visiting the coast. The Tsunami Warning Center in Mexico recently created (September 19, 2011) monitors earthquakes and sea level change caused by these same. Sea level on the west coast of the Mexican Pacific was analyzed after the occurrence of local, regional and distant earthquakes, in order to determine the existence of an anomaly due to the quake itself. Variations in sea level due to local registered earthquakes Mw 6.0 to 7.4 range was from 0.10 to 0.30 m; for regional earthquakes of Mw 7.3 and 8.2 were 0.12 and 0.22 m respectively and to the distant earthquake of Mw 8.0 recorded in Solomon Islands, the change in sea level of the maximum recorded was 0.20 m in Manzanillo, Colima. It is important to know that earthquakes whether local, regional or distant whose magnitudes are in the range specified here, did not present a risk to the Mexican coast, but do not rely, having to monitor variations in sea level that earthquakes can produce and be aware that you may perhaps occur as a tsunami in Indonesia in 2004 or Japan in 2011.