Biogenic opal and ice‐rafted detritus (IRD) data from sediments in the Okhotsk Sea and the neighboring North Pacific revealed the remarkable reduction in opal production and southward advancement of sea‐ice covered area during the last glacial maximum, resulting also southward shift of high biological productive area in the northwestern North Pacific. It implies that the substantial reduction in outflux of CO2 to the atmosphere in northwestern North Pacific and the pronounced increase in CO2 sequestering in temperate North Pacific. This could be an additional CO2 reduction mechanism of atmospheric CO2 in the last glacial period.

Abstract. A piston core taken from the Tasman Plateau inthe Southern Ocean has been studied for organic compounds to reconstruct the late Pleistocene marine environments.Here we report paleo sea surface temperature (SST) for the last two deglaciations using the unsaturation degree of alkenones (Uk37 ') preserved in the marine sediments. The Uk37 ' record indicates that the SST was at least 4øC lower than the present SST at the last glacial maximum (LGM), and the amplitude of paleo-SST is at most 5.2øC from the penultimate glacial (MIS-6) to the last interglacial warm period (the Eemian). Our results also demonstrate that the Eemian warm period in the Southern Ocean lasted only 3,000 years followed by a sharp cooling at around 120 kyr B P. The sharp cooling in the Southern Ocean seemed to occur a few millennia (2-3 kyrs) before the beginning of continental ice-sheet growth.

A discrete cosine transform (DCT) can be easily implemented in software and hardware for the JPEG and MPEG formats. However, even though some integer DCTs (IntDCTs) for lossless-to-lossy image coding have been proposed, such transform requires redesigned devices. This paper proposes a hardware-friendly IntDCT that can be applied to both lossless and lossy coding. Our IntDCT is implemented by direct-lifting of DCT and inverse DCT (IDCT). Consequently, any existing DCT device can be directly applied to every lifting block. Although our method requires a small side information block (SIB), it is validated by its application to lossless-to-lossy image coding.

In this paper, the theory, structure, design, and implementation of a new class of linear-phase paraunitary filter banks (LPPUFB's) are investigated. The novel filter banks with filters of different lengths can be viewed as the generalized lapped orthogonal transforms (GenLOT's) with variable-length basis functions. Our main motivation is the application in blocktransform-based image coding. Besides having all of the attractive properties of other lapped orthogonal transforms, the new transform takes advantage of its long, overlapping basis functions to represent smooth signals in order to reduce blocking artifacts, whereas it reserves short basis functions for high-frequency signal components like edges and texture, thereby limiting ringing artifacts. Two design methods are presented, each with its own set of advantages: The first is based on a direct lattice factorization, and the second enforces certain relationships between the lattice coefficients to obtain variable length filters. Various necessary conditions for the existence of meaningful solutions are derived and discussed in both cases. Finally, several design and image coding examples are presented to confirm the validity of the theory.

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We presented the total and inorganic carbon contents of core samples recovered from the Taiwan Chelungpu fault system, which slipped at the 1999 Chi-Chi earthquake, and reported lower contents of inorganic carbon within the black gouge zone in FZB1136 (fault zone at depth 1136 m in Hole B) and in the black-material disks in FZB1194 and FZB1243.

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