Deep-sea hydrothermal vent fields are areas on the seafloor with high biological productivity fueled by microbial chemosynthesis. Members of the Aquificales genus Persephonella are obligately chemosynthetic bacteria, and appear to be key players in carbon, sulfur, and nitrogen cycles in high temperature habitats at deep-sea vents. Although this group of bacteria has cosmopolitan distribution in...

introduction climate change is an important environmental hazard that has been discussed in recent years. increasing the number or frequency of extreme climatic events such as severe droughts, floods, storms, heat and cold waves and heavy rains are the evidences of climate change. any of these events, due to the severity and persistence and their spread are a natural hazard that adverse effects...

in this research, the correlation between precipitation change in southern coasts of caspian sea and variability of sea level pressure have been analyzed by using environmental to circulation approach at time period 1339- 1383. in this respect, we make use of daily precipitation data of the 12 synoptic stations of studied area at surface data base section and prepare the time series matrix of p...

Although the rare earth element (REE) geochemistry of hydrothermal systems have intensively been investigated at mid-oceanic ridges, studies are relatively few at the converging plate zones like the Okinawa Trough. The “chimney” deposits obtained by using submersible “SHINKAI 2000” from the Iheya Ridge site, Okinawa Trough are largely composed of massive carbonates and silicates with minor amou...

Using monthly gridded 500-hPa data, two synoptic indices are defined to better understand the principle mechanisms controlling intraseasonal to multiannual winter climate variability in New England (NE). The ‘‘trough axis index’’ (TAI) is created to quantify the mean longitudinal position of the common East Coast pressure trough, and the ‘‘trough intensity index’’ (TII) is calculated to estimat...

To validate the abundance of scenarios of large earthquakes in the Nankai Trough, we examined the effects of both lateral and vertical expansions of the source areas on maximum tsunami heights along the Pacific coast and Seto Inland Sea. The recently proposed Nankai Trough earthquake scenario (Mw = 9) has a maximum slip of 20 m near the trough axis. However, the predicted tsunami heights exceed...

i introduction convective systems are atmospheric events that are associated with hazardous consequences, such as strong wind drafts, lightning, heavy rainfall, hail, or even tornado. they are manifested in the atmosphere within a broad range of spatial and temporal scales. a convection cell is composed of two distinct regions: the actual convective part which consists of the coldest intense ve...

abstract many people know the important effects of caspian sea winds and storms on the economy of three provinces of iran including gilan, mazandaran, and golestan that they form one exclusive and extent area which have moderate and humid climate. this paper used a synoptic climatologically approach, which combine a number of atmospheric factors. using daily and monthly winds data including the...

During late boreal summer (July–October), the intraseasonal oscillation (ISO) exhibits maximum variability over the western North Pacific (WNP) centered in the South China Sea and Philippine Sea, but many numerical models have difficulty in simulating this essential feature of the ISO. To understand why this maximum variability center exists, the authors advance a simple box model to elaborate ...