The Indonesian Throughflow(ITF), which connects the tropical Pacific and Indian oceans, plays important roles in the inter-ocean water exchange and regional or even global climate variability. The Makassar Strait is t...The Indonesian Throughflow(ITF), which connects the tropical Pacific and Indian oceans, plays important roles in the inter-ocean water exchange and regional or even global climate variability. The Makassar Strait is the main inflow passage of the ITF, carrying about 77% of the total ITF volume transport. In this study, we analyze the simulated ITF in the Makassar Strait in the Simple Ocean Data Assimilation version 3(SODA3) datasets. A total of nine ensemble members of the SODA3 datasets, of which are driven by different surface forcings and bulk formulas, and with or without data assimilation, are used in this study. The annual mean water transports(i.e.,volume, heat and freshwater) are related to the combination of surface forcing and bulk formula, as well as whether data assimilation is employed. The phases of the seasonal and interannual variability in water transports cross the Makassar Strait, are basically consistent with each other among the SODA3 ensemble members. The interannual variability in Makassar Strait volume and heat transports are significantly correlated with El Ni?oSouthern Oscillation(ENSO) at time lags of-6 to 7 months. There is no statistically significant correlation between the freshwater transport and the ENSO. The Makassar Strait water transports are not significantly correlated with the Indian Ocean Dipole(IOD), which may attribute to model deficiency in simulating the propagation of semiannual Kelvin waves from the Indian Ocean to the Makassar Strait.展开更多
The central Pacific(CP) zonal wind divergence and convergence indices are defined, and the forming mechanism of CP El Nio(La Nia) events is discussed preliminarily. The results show that the divergence and converg...The central Pacific(CP) zonal wind divergence and convergence indices are defined, and the forming mechanism of CP El Nio(La Nia) events is discussed preliminarily. The results show that the divergence and convergence of the zonal wind anomaly(ZWA) are the key process in the forming of CP El Nio(La Nia) events. A correlation analysis between the central Pacific zonal wind divergence and convergence indices and central Pacific El Nio indices indicates that there is a remarkable lag correlation between them. The central Pacific zonal wind divergence and convergence indices can be used to predict the CP events. Based on these results, a linear regression equation is obtained to predict the CP El Nio(La Nia) events 5 months ahead.展开更多
The 2002/03 El Ni?o event, a new type of El Ni?o with maximum warm anomaly occurring in the central equatorial Pacific, is known as central-Pacific(CP) El Ni?o. In this study, on the basis of an El Ni?o predicti...The 2002/03 El Ni?o event, a new type of El Ni?o with maximum warm anomaly occurring in the central equatorial Pacific, is known as central-Pacific(CP) El Ni?o. In this study, on the basis of an El Ni?o prediction system, roles of the initial ocean surface and subsurface states on predicting the 2002/03 CP El Ni?o event are investigated to determine conditions favorable for predicting El Ni?o growth and are isolated in three sets of hindcast experiments. The hindcast is initialized through assimilation of only the sea surface temperature(SST)observations to optimize the initial surface condition(Assim_SST), only the sea level(SL) data to update the initial subsurface state(Assim_SL), or both the SST and SL data(Assim_SST+SL). Results highlight that the hindcasts with three different initial states all can successfully predict the 2002/03 El Ni?o event one year in advance and that the Assim_SST+SL hindcast performs best. A comparison between the various sets of hindcast results further demonstrates that successful prediction is significantly affected by both of the initial surface and subsurface conditions, but in different developing phases of the 2002/03 El Ni?o event. The accurate initial surface state can easier trigger the prediction of the 2002/03 El Ni?o, whereas a more reasonable initial subsurface state can contribute to improving the prediction in the growth of the warm event.展开更多
To study how the air and sea interact with each other during El Nifio/La Nifia onsets, extended associate pattern analysis (EAPA) is adopted with the simple ocean data assimilation (SODA) data. The results show th...To study how the air and sea interact with each other during El Nifio/La Nifia onsets, extended associate pattern analysis (EAPA) is adopted with the simple ocean data assimilation (SODA) data. The results show that as El Niйo/La Niйa's parents their behaviors are quite different, there does not exist a relatively independent tropical atmosphere but does exist a relatively independent tropical Pacific Ocean because the air is heated from the bottom surface instead of the top surface and of much stronger baroclinic instability than the sea and has a very large inter-tropical convergence zone covering the most tropical Pacific Ocean. The idea that it is the wester burst and wind convergence, coming from middle latitudes directly that produce the seawater eastward movement and meridional convergence in the upper levels and result in the typical E1 Nifio sea surface temperature warm signal is confirmed again.展开更多
Wadi El Assiuti represents a promising area for agricultural development and building new communities far from the overpopulated areas in the Nile Val-ley. An integrated approach of satellite-based data and geophysica...Wadi El Assiuti represents a promising area for agricultural development and building new communities far from the overpopulated areas in the Nile Val-ley. An integrated approach of satellite-based data and geophysical data with borehole data was used for defining the area of interest, the sediment thick-ness, delineating the subsurface structures, and mapping the depth to the basement rocks, and defining the groundwater aquifers. Findings are: 1) Dramatic changes are detected in the anthropogenic activities at the entrance area of the wadi, making stress and heavy exploitation of the groundwater resources. However, the central and northeastern regions show no development;2) Several structural trends in the directions of NNW, NW, NE, and E-W are cutting the basement rocks and sedimentary cover;3) The depth to the basement rocks is increasing eastward from ~2.24 km to ~4.84 km;4) Three groundwater-bearing reservoirs are represented by the shallow Qua-ternary, the fractured limestone, and the deep Nubian sandstone aquifers;5) The deep-seated faults are affecting the area and rising groundwater from the deeper Nubian aquifer along its sub-vertical trend;and 6) The results are in-formative and used to define the suitable sites for water well drilling.展开更多
The area around Aswan-Berenice Road southeast Aswan is geophysically studied to delineate the subsurface structures and to evaluate the tectonic framework of the basement rocks and the overlying sedimentary cover. Thi...The area around Aswan-Berenice Road southeast Aswan is geophysically studied to delineate the subsurface structures and to evaluate the tectonic framework of the basement rocks and the overlying sedimentary cover. This area comprises a variety of igneous, metamorphic and sedimentary rocks, ranging in age from Precambrian to Quaternary time. The interpretation of the aeromagnetic data around Aswan-Berenice Road was carried out using GM-SYS modeling technique. Many methods were performed to the RTP aeromagnetic map of the study area such as filtering and trend analysis techniques. The tracing upward and downward of the deduced subsurface structures was investigated using trend analysis for the surface geology and filtered magnetic maps. The locating and determination of the approximate depth of the causative bodies were done using Euler deconvolution, Werner deconvolution and 2.5 dimension magnetic modeling techniques. The obtained results indicate that the most significant tectonic trends are N-S and E-W, which they are in accordance with the local trends of River Nile and Kalabsha fault respectively. Less common trends as NW-SE and NE-SW directions are also detected. Also, the depth to the basement rocks ranges from 0 km at the exposed parts to 1.4 km at the covered parts.展开更多
The objective of this paper is to utilize images of spatial and temporal fluctuations of temperature over the Earth to study the global climate variation. We illustrated that monthly temperature observations from weat...The objective of this paper is to utilize images of spatial and temporal fluctuations of temperature over the Earth to study the global climate variation. We illustrated that monthly temperature observations from weather stations could be decomposed as components with different time scales based on their spectral distribution. Kolmogorov-Zurbenko (KZ) filters were applied to smooth and interpolate gridded temperature data to construct global maps for long-term (≥ 6 years) trends and El Nino-like (2 to 5 years) movements over the time period of 1893 to 2008. Annual temperature seasonality, latitude and altitude effects have been carefully accounted for to capture meaningful spatiotemporal patterns of climate variability. The result revealed striking facts about global temperature anomalies for specific regions. Correlation analysis and the movie of thermal maps for El Nino-like component clearly supported the existence of such climate fluctuations in time and space.展开更多
基金The Fund of Laoshan Laboratory under contract No. LSKJ202202700the National Natural Science Foundation of China under contract Nos 42076023, 42076024 and 41876027the Global Change and Air-Sea Interaction Ⅱ Project under contract No.GASI-01-AIP-STwin。
文摘The Indonesian Throughflow(ITF), which connects the tropical Pacific and Indian oceans, plays important roles in the inter-ocean water exchange and regional or even global climate variability. The Makassar Strait is the main inflow passage of the ITF, carrying about 77% of the total ITF volume transport. In this study, we analyze the simulated ITF in the Makassar Strait in the Simple Ocean Data Assimilation version 3(SODA3) datasets. A total of nine ensemble members of the SODA3 datasets, of which are driven by different surface forcings and bulk formulas, and with or without data assimilation, are used in this study. The annual mean water transports(i.e.,volume, heat and freshwater) are related to the combination of surface forcing and bulk formula, as well as whether data assimilation is employed. The phases of the seasonal and interannual variability in water transports cross the Makassar Strait, are basically consistent with each other among the SODA3 ensemble members. The interannual variability in Makassar Strait volume and heat transports are significantly correlated with El Ni?oSouthern Oscillation(ENSO) at time lags of-6 to 7 months. There is no statistically significant correlation between the freshwater transport and the ENSO. The Makassar Strait water transports are not significantly correlated with the Indian Ocean Dipole(IOD), which may attribute to model deficiency in simulating the propagation of semiannual Kelvin waves from the Indian Ocean to the Makassar Strait.
基金The National Basic Research Program(973 Program)of China under contract No.2012CB417402the Strategic Priority Research Program of the Chinese Academy of Sciences under contract No.XDA11010102
文摘The central Pacific(CP) zonal wind divergence and convergence indices are defined, and the forming mechanism of CP El Nio(La Nia) events is discussed preliminarily. The results show that the divergence and convergence of the zonal wind anomaly(ZWA) are the key process in the forming of CP El Nio(La Nia) events. A correlation analysis between the central Pacific zonal wind divergence and convergence indices and central Pacific El Nio indices indicates that there is a remarkable lag correlation between them. The central Pacific zonal wind divergence and convergence indices can be used to predict the CP events. Based on these results, a linear regression equation is obtained to predict the CP El Nio(La Nia) events 5 months ahead.
基金The National Program for Support of Top-notch Young Professionalsthe Project of Global Change and Air-Sea Interaction+1 种基金the National Basic Research Program(973 Program)of China under contract No.2012CB417404the Project"Western Pacific Ocean System:Structure,Dynamics and Consequences"(WPOS)of Chinese Academy Sciences under contract No.XDA10010405
文摘The 2002/03 El Ni?o event, a new type of El Ni?o with maximum warm anomaly occurring in the central equatorial Pacific, is known as central-Pacific(CP) El Ni?o. In this study, on the basis of an El Ni?o prediction system, roles of the initial ocean surface and subsurface states on predicting the 2002/03 CP El Ni?o event are investigated to determine conditions favorable for predicting El Ni?o growth and are isolated in three sets of hindcast experiments. The hindcast is initialized through assimilation of only the sea surface temperature(SST)observations to optimize the initial surface condition(Assim_SST), only the sea level(SL) data to update the initial subsurface state(Assim_SL), or both the SST and SL data(Assim_SST+SL). Results highlight that the hindcasts with three different initial states all can successfully predict the 2002/03 El Ni?o event one year in advance and that the Assim_SST+SL hindcast performs best. A comparison between the various sets of hindcast results further demonstrates that successful prediction is significantly affected by both of the initial surface and subsurface conditions, but in different developing phases of the 2002/03 El Ni?o event. The accurate initial surface state can easier trigger the prediction of the 2002/03 El Ni?o, whereas a more reasonable initial subsurface state can contribute to improving the prediction in the growth of the warm event.
文摘To study how the air and sea interact with each other during El Nifio/La Nifia onsets, extended associate pattern analysis (EAPA) is adopted with the simple ocean data assimilation (SODA) data. The results show that as El Niйo/La Niйa's parents their behaviors are quite different, there does not exist a relatively independent tropical atmosphere but does exist a relatively independent tropical Pacific Ocean because the air is heated from the bottom surface instead of the top surface and of much stronger baroclinic instability than the sea and has a very large inter-tropical convergence zone covering the most tropical Pacific Ocean. The idea that it is the wester burst and wind convergence, coming from middle latitudes directly that produce the seawater eastward movement and meridional convergence in the upper levels and result in the typical E1 Nifio sea surface temperature warm signal is confirmed again.
文摘Wadi El Assiuti represents a promising area for agricultural development and building new communities far from the overpopulated areas in the Nile Val-ley. An integrated approach of satellite-based data and geophysical data with borehole data was used for defining the area of interest, the sediment thick-ness, delineating the subsurface structures, and mapping the depth to the basement rocks, and defining the groundwater aquifers. Findings are: 1) Dramatic changes are detected in the anthropogenic activities at the entrance area of the wadi, making stress and heavy exploitation of the groundwater resources. However, the central and northeastern regions show no development;2) Several structural trends in the directions of NNW, NW, NE, and E-W are cutting the basement rocks and sedimentary cover;3) The depth to the basement rocks is increasing eastward from ~2.24 km to ~4.84 km;4) Three groundwater-bearing reservoirs are represented by the shallow Qua-ternary, the fractured limestone, and the deep Nubian sandstone aquifers;5) The deep-seated faults are affecting the area and rising groundwater from the deeper Nubian aquifer along its sub-vertical trend;and 6) The results are in-formative and used to define the suitable sites for water well drilling.
文摘The area around Aswan-Berenice Road southeast Aswan is geophysically studied to delineate the subsurface structures and to evaluate the tectonic framework of the basement rocks and the overlying sedimentary cover. This area comprises a variety of igneous, metamorphic and sedimentary rocks, ranging in age from Precambrian to Quaternary time. The interpretation of the aeromagnetic data around Aswan-Berenice Road was carried out using GM-SYS modeling technique. Many methods were performed to the RTP aeromagnetic map of the study area such as filtering and trend analysis techniques. The tracing upward and downward of the deduced subsurface structures was investigated using trend analysis for the surface geology and filtered magnetic maps. The locating and determination of the approximate depth of the causative bodies were done using Euler deconvolution, Werner deconvolution and 2.5 dimension magnetic modeling techniques. The obtained results indicate that the most significant tectonic trends are N-S and E-W, which they are in accordance with the local trends of River Nile and Kalabsha fault respectively. Less common trends as NW-SE and NE-SW directions are also detected. Also, the depth to the basement rocks ranges from 0 km at the exposed parts to 1.4 km at the covered parts.
文摘The objective of this paper is to utilize images of spatial and temporal fluctuations of temperature over the Earth to study the global climate variation. We illustrated that monthly temperature observations from weather stations could be decomposed as components with different time scales based on their spectral distribution. Kolmogorov-Zurbenko (KZ) filters were applied to smooth and interpolate gridded temperature data to construct global maps for long-term (≥ 6 years) trends and El Nino-like (2 to 5 years) movements over the time period of 1893 to 2008. Annual temperature seasonality, latitude and altitude effects have been carefully accounted for to capture meaningful spatiotemporal patterns of climate variability. The result revealed striking facts about global temperature anomalies for specific regions. Correlation analysis and the movie of thermal maps for El Nino-like component clearly supported the existence of such climate fluctuations in time and space.