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51.
Dewan Abdul Quadir Madan L. Shrestha Tariq Masood Ali Khan Nazlee Ferdousi Mizanur Rahman Abdul Mannan 《Natural Hazards》2004,31(2):561-584
The inter-annual variation and linear trends of the surface air temperature in the regions in and around the Bay of Bengal have been studied using the time series data of monthly and annual mean temperature for 20–40 years period within 1951–1990. The study area extends from Pusma Camp of Nepal in the north and Kuala Lumpur of Malaysia in the south and between 80--100 ° E. The annual variation of temperature has also been studied using the mean monthly temperature for the variable time frames 1961–1975, 1976–1990 and 1961–1990. The trend of temperature has been analyzed using linear regression technique with the data from 1961–1990, which showed that the warming trend is dominant over the study areas except for a few stations. It has been found that Nepal shows predominant warming trends. Bangladesh and the adjacent areas of India and the northern part of Bay of Bengal adjacent to the Bangladesh coast have shown strong warming trends of the annual temperature with maximum at Dhaka (0.037 °C/year). The near equatorial zone, i.e., southern India, Sri Lanka and part of Thailand and Malaysia (Kuala Lumpur) shows warming trends in the annual mean temperature with strong warming at Pamban and Anuradhapura (around 0.04 °C/year). The cooling trends have been observed at a few stations including Port Blair, Yangoon and Cuttack. Further analysis shows the presence of prominent ENSO scale of variations with time period 4–7 years and 2–3 years for almost all the stations. The decadal mode with T >7 years is present in some data series. The results of the variations of temperature with respect to the Southern Oscillation Index (SOI) show that SOI has some negative correlation with temperature for most of the stations except those in the extreme northeast. It has been found that positive anomaly of temperature has been observed for El Niño events and negative anomaly for the La Nina events. 相似文献
52.
Geotectonics - The collision of the Eurasian and Indian plates has resulted in two spatially offset subduction zones, the Makran subduction zone to the south and the Himalayan convergent margin to... 相似文献
53.
Priyanka Tripathi G. Parthasarathy S. Masood Ahmad O. P. Pandey 《International Journal of Earth Sciences》2012,101(5):1385-1395
We report here for the first time geochemical, mineralogical and stable carbon and oxygen isotopic data on the crystalline basement rocks of the 1993 Killari earthquake region of Maharashtra (India), which is covered by a thick suite of Deccan volcanics. Our results revealed the hitherto unknown amphibolite–granulite nature of the 2.5?Ga basement, which contains 2.00–2.28?wt% of CO2. The stable carbon (δ13C) and oxygen (δ18O) isotopic measurements on carbonates separated from two basement samples KIL-13 (440.5?m depth) and KIL-20 (499.6?m depth) collected from the KLR-1 borehole drilled in the epicentral region showed the respective values of ?6.23 and ?6.22‰ versus PDB for δ13C and 7.94 and 8.11‰ versus SMOW for δ18O. The samples plot in the primary igneous carbonatite field, indicating the mantle origin of the carbonates, derived through the process of mantle metasomatism from the deep mantle carbon reservoir. This would suggest large-scale crust-mantle thermal fluid interaction beneath the Killari seismogenic region, which is characterized by massive upwarping of the high-velocity mafic crust and retrograde metamorphism. 相似文献
54.
Relative Sea Level Changes in Maldives and Vulnerability of Land Due to Abnormal Coastal Inundation 总被引:1,自引:0,他引:1
Tariq Masood Ali Khan Dewan Abdul Quadir T. S. Murty Anwarul Kabir Fahmida Aktar Majajul Alam Sarker 《Marine Geodesy》2013,36(1-2):133-143
Oceanic Islands in the Pacific and Indian Oceans have extremely small land areas, usually less than 500 km2, with maximum height about 4 m above sea level. The Republic of Maldives is an independent island nation in the Indian Ocean south of Sri Lanka which stretches vertically in the Indian Ocean from 07° 06'N - 0° 42'S. The land area of this island country is about 300 km2, and none of Maldives' 1190 islands has an elevation more than 3 m above sea level. In fact the Maldives has the distinction of being the flattest country on earth, making it extremely vulnerable to the effects of global warming. Of the south Asian countries, the Maldives is the most vulnerable nation, facing severe consequences as a result of global warming and sea level rise (SLR). Because of their obvious vulnerability to SLR, the Government of Maldives is very much concerned about climate change. As global warming and the related SLR is an important integrated environmental issue, the need of the hour is to monitor and assess these changes. The present article deals mainly with the analysis of the tidal and Sea Surface Temperature (SST) data observed at Male and Gan stations along the Maldives coast in the northern and southern hemispheres, respectively. The objective of the analysis is to study the trends of these parameters. Trend analysis is also performed on the corresponding air temperature data of both stations. The results show that Maldives coastal sea level is rising in the same way (rising trend) as the global sea level. The mean tidal level at Male has shown an increasing trend of about 4.1 mm/year.Similarly at Gan, near the equator,it has registered a positive trend of about 3.9 mm/year.Sea level variations are the manifestations of various changes that are taking place in the Ocean-Atmosphere system. Therefore, the variations in SST and air temperature are intimately linked to sea level rise. It is found that SST and air temperature have also registered an increasing trend at both stations. The evidence of rising trends suggest that careful future monitoring of these parameters is very much required. Tropical cyclones normally do not affect the Maldives coast. However, due to its isolated location, the long fetches in association with swells generated by storms, that originated in the far south have resulted in flooding. Thus the rising rate of sea level with high waves and flat topography have increased the risk of flooding and increased the rate of erosion and alteration of beaches. 相似文献