Sea surface temperture reconstruction and planktonic foraminifera of ODP Hole 117-723A

In the western Arabian Sea (WAS), the highest seasonal sea surface temperature (SST) difference presently occurs between May and August. In order to gain an understanding on how monsoonal upwelling modulates the SST difference between these two months, we have computed SST for the months of May and August based on census counts of planktonic foraminifers by using the artificial neural network (ANN) technique. The SST difference between May and August exhibits three distinct phases: i) a moderate SST difference in the late Holocene (0-3.5 ka) is attributable to intense upwelling during August, ii) a minimum SST difference from 4 to 12 ka is due to weak upwelling during the month of August, and iii) the highest SST difference during the last glacial interval (19 to 22 ka) with high Globigerina bulloides % could have been caused by the occurrence of a prolonged upwelling season (from May through July) and maximum difference in the incoming solar radiation between May and August. Overall, variations in the SST difference between May and August show that the timing of intense upwelling in the Western Arabian Sea over the last 22 kyr has been variable over the months of June, July and August.

The sedimentology and diagenesis of Lower Permian (Rotliegend) sediments: (onshore U.K. and southern North Sea). Available in 2 volumes.

The thesis provides a comparative study of both sedimentology and diagenesis of Lower Permian (Rotliegend) strata, onshore and offshore U.K. (Southern North Sea). Onshore formations studied include the Bridgnorth, Penrith and Hopeman Sandstone, and are dominated by aeolian facies, with lesser amounts of interbedded fluvial sediments. Aeolian and fluvial strata in onshore basins typically grade laterally into alluvial fan breccias at basin margins. Onshore basins represent proximal examples of Rotliegend desert sediments. The Leman Sandstone Formation of the Ravenspurn area in the Southern North Sea displays a variety of facies indicative of a distal sedimentological setting; Aeolian, fluvial, sabkha, and playa lake sediments all being present. "Sheet-like" geometry of stratigraphical units within the Leman Sandstone, and alternation of fluvial and aeolian deposition was climatically controlled. Major first order bounding surfaces are laterally extensive and were produced by lacustrine transgression and regression from the north-west. Diagenesis within Permian strata was studied using standard petrographic microscopy, scanning electron microscopy, cold cathodo-Iuminescence, X-ray diffraction clay analysis, X-ray fluorescence spectroscopy, fluid inclusion microthermometry, and K-Ar dating of illites. The diagenesis of Permian sediments within onshore basins is remarkably similar, and a paragenetic sequence of early haematite, illitic clays, feldspar, kaolinite, quartz and late calcite is observed. In the Leman Sandstone formation, authigenic mineralogy is complex and includes early quartz, sulphates and dolomite, chlorite, kaolinite, late quartz, illite and siderite. Primary lithological variation, facies type, and the interdigitation and location of facies within a basin are important initial controls upon diagenesis. Subsequently, burial history, structure, the timing of gas emplacement, and the nature of sediments within underlying formations may also exersize significant controls upon diagenesis within Rotliegend strata.

(Table I-II) Station details and isopoda abundance of samples taken during POLARSTERN cruise ANT-XV/3 to the eastern Weddell Sea and King George Island

Abundance, diversity, and distribution of suprabenthic Isopoda caught from a water layer between 0.27 to 0.60 m above the seafloor were analysed. The samples were taken during the ANT XV/3 cruise on RV Polarstern by means of an epibenthic sledge along two transects in the southern Weddell Sea (Vestkapp and Halley Bay) and another one east of King George Island. At each of these three bathymetric transects, five to six stations were sampled between 200 and 2000 m. In total, 4258 specimens of isopods were sampled at 14 stations standardized to 1000 m2 hauls. 114 species were identified from 49 genera and 23 higher taxa (families and suborders) of Isopoda. Most of them belonged to the suborder Asellota. Dominant families are Munnopsididae (Eurycopinae, Ilyarachninae), Joeropsidae, Munnidae, Paramunnidae, Ischnomesidae and Desmosomatidae. No striking differences were found between areas (Vestkapp, Halley Bay, Kapp Norvegia, and Bransfield Strait). Overall isopod abundances were highest at the shallowest station; species richness was slightly higher above 1000 m depth.

Intact and core tetraether lipids in water column profiles of suspended particulate matter and of surface sediment samples off Cape Blanc, NW Africa

In the reconstruction of sea surface temperature (SST) from sedimentary archives, secondary sources, lateral transport and selective preservation are considered to be mainly negligible in terms of influencing the primary signal. This is also true for the archaeal glycerol dialkyl glycerol tetraethers (GDGTs) that form the basis for the TEX86 SST proxy. Our samples represent four years variability on a transect off Cape Blanc (NW Africa). We studied the subsurface production, vertical and lateral transport of intact polar lipids and core GDGTs in the water column at high vertical resolution on the basis of suspended particulate matter (SPM) samples from the photic zone, the subsurface oxygen minimum zone (OMZ), nepheloid layers (NL) and the water column between these. Furthermore we compared the water column SPM GDGT composition with that in underlying surface sediments. This is the first study that reports TEX86 values from the precursor intact polar lipids (IPLs) associated with specific head groups (IPL -specific TEX86). We show a clear deviation from the sea surface GDGT composition in the OMZ between 300 and 600 m. Since neither lateral transport nor selective degradation provides a satisfactory explanation for the observed TEX-derived temperature profiles with a bias towards higher temperatures for both core- and IPL -specific TEX86 values, we suggest that subsurface in situ production of archaea with a distinct relationship between lipid biosynthesis and temperature is the responsible mechanism. However, in the NW-African upwelling system the GDGT contribution of the OMZ to the surface sediments does not seem to affect the sedimentary TEX86 as it shows no bias and still reflects the signal of the surface waters between 0 and 60 m.

Extralimital Senegalese species during Marine Isotope Stages 5.5 and 11 in the Canary Islands (29 degrees N): Sea surface temperature estimates

[EN] The presence of Harpa doris Röding, 1798 in marine deposits of the last interglacial period, ~. 130-120. ka (marine isotope stage or MIS 5.5) in the Canary Islands (Gran Canaria, Lanzarote and Fuerteventura) enabled us to compare this occurrence with its present habitat in the Gulf of Guinea and the Cape Verde Islands, well to the south. This comparison leads to the conclusion that sea surface temperatures (SSTs) in the waters around the Canary Islands during the last interglacial period were at least 3.3. °C higher than today. H. doris is found in association with the large gastropod Persististrombus latus (Gmelin, 1791) as well as the coral Siderastrea radians (Pallas, 1766).

On the effect of Arabian Sea and Indian Ocean sea surface temperature anomaly on the monsoon rainfall of south-east of Iran

Southeast region of the country has hot and dry weather which causes to happen heavy rainfall in short time period of warm seasons and to occur river flooding. These precipitations are influenced by monsoon system of India ocean. In these thesis, It was tried to evaluate the relation between thermal anomaly of sea surface in India ocean and Arab sea which effects on southeast monsoon precipitations of Iran, For evaluation of this happening in southeast, data were collected from 7 synoptic observation stations of Bandar Abbas, Minab, Kerman , Bam, Chabahar, Iranshahr, Zahedan and 17 rain gauge stations during June to September of each year from 1980 to 2010. Rainy days were determine and then some information about synoptic circulation models, maps of average pressure of sea surface, geopotential height of 700hP surface, geopotential height of 500hP surface, temperature of 850 hPa surface, humidity of 700 hPa surface, vertical velocity of 700 hPa surface, vertical velocity of 500 hP and humidity of 2 meters height for 6 systems were extracted from NCEP/NCAR website for evaluation. By evaluation of these systems it was determined that the monsoon low pressure system tab brings needed humidity of these precipitations to this region from India ocean and Arab sea with a vast circulation. It is seen that warm air pool locates on Iran and cold air pool locates on west of India at 800 hPa surface. In a rainy day this warm air transfers to high latitudes and influences the temperature trough of southeast cold air pool of the country. In the middle surfaces of 700 and 500 hPa, the connection between low height system above India and low height system above the higher latitudes causes the low height system above India to be strength and developed. By evaluation of humidity at 2 meters height and 700 hPa surface we observe that humidity Increases in the southeast region. With penetrating of the low height system of India above the 700 and 500 hPa surfaces of southeast of Iran, the value of negative omega (Rising vertical velocity) is increased. In the second pace, it was shown the evaluation of how the correlation between sea surface temperature anomaly in India Ocean and Arab sea influences southeast monsoon precipitation of Iran. For this purpose the data of water surface temperature anomaly of Arab sea and India ocean, the data of precipitation anomaly of 7 synoptic stations , mentioned above, and correlation coefficient among the data of precipitation anomaly and water surface temperature anomaly of Arab Sea, east and west of India ocean were calculated. In conclusion it was shown that the maximum correlation coefficient of precipitation anomaly had belonged to India Ocean in June and no meaningful correlation was resulted in July among precipitation anomaly and sea surface temperature anomaly for three regions, which were evaluated.

Geomorphology, sedimentary processes and development of the Zenisu deep-sea channel, northern Philippine Sea

The Zenisu deep-sea channel originates on the Izu-Ogasawara island arc, and disappears in the Shikoku Basin of the Philippine Sea. The geomorphology, sedimentary processes, and the development of the Zenisu deep-sea channel were investigated on the basis of swath bathymetry, side-scan sonar imagery, submersible observations, and seismic data. The deep-sea channel can be divided into three segments according to the downslope gradient and channel orientation. They are the Zenisu Canyon, the E-W fan channel, and the trough-axis channel. The sediment fill is characterized by turbidite and debrite deposition and blocky-hummocky avalanche deposits on the flanks of the Zenisu Ridge. In the Zenisu Canyon and the Zenisu deep-sea channel, sediment transport by turbidity currents generates sediment waves (dunes) observed during the Shinkai 6500 dive 371. The development of the Zenisu Canyon is controlled by a N-S shear fault, whereas the trough-axis channel is controlled by basin subsidence associated with the Zenisu Ridge. The E-W fan channel was probably affected by the E-W fault and the basement morphology.

Long-term annual primary production in the Ulleung Basin as a biological hot spot in the East/Japan Sea

Although the Ulleung Basin is an important biological hot spot in East/Japan Sea (hereafter the East Sea), very limited knowledge for seasonal and annual variations in the primary productivity exists. In this study, a recent decadal trend of primary production in the Ulleung Basin was analyzed based on MODIS-derived monthly primary production for a better annual production budget. Based on the MODIS-derived primary production, the mean daily primary productivity was 766.8 mg C m-2 d-1 (SD=+/- 196.7 mg C m-2 d-1) and the annual primary productivity was 280.2 g C m-2 yr-1 (SD=+/- 14.9 g C m-2 yr-1) in the Ulleung Basin during the study period. The monthly contributions of primary production were not largely variable among different months, and a relatively small interannual production variability was also observed in the Ulleung Basin, which indicates that the Ulleung Basin is a sustaining biologically productive region called as hot spot in the East Sea. However, a significant recent decline in the annual primary production was observed in the Ulleung Basin after 2006. Although no strong possibilities were found in this study, the current warming sea surface temperature and a negative phase PDO index were suggested for the recent declining primary production. For a better understanding of subsequent effects on marine ecosystems, more intensive interdisciplinary field studies will be required in the Ulleung Basin.

Strontium measurements and sea surface temperatures of corals from Xisha Island, South China Sea

A Porites coral collected from Xisha Island, South China Sea, represents a skeleton secreted in the period from 1906 to 1994. The Sr contents of the coral vary linearly with the instrument-measured sea-surface temperature (SST), giving a Sr thermometer: SST = -1.9658 x Sr + 193.26. The reconstructed SST data show that the late 20th century was warmer (about 1°C) than the early 20th century and that two cooling (1915/1916 and 1947/1948) and three warming (1935/1936, 1960/1961, and 1976/1977) shifts occurred in the century. The temperature shifts are more pronounced for winters, implying a close effect of the west Pacific warm pool and Asian monsoon and suggesting that the former is a primary force controlling the climatic system of the region. Results of this study and previously published data indicate a close link of temperature shifts between the boreal summer and the austral winter or the boreal winter and the austral summer. The annual SST anomalies in the South China Sea and the South Pacific reveal the existence of harmonic but opposite SST variations between the two regions. On the decadal scale the comparative annual SST anomalies for the South China Sea and for the equatorial west Pacific show a similarity in temperature variations, implying that the South China Sea climate is coherent with climatic regime of the tropical west Pacific.