Observations of an intrusion of a warmer and less saline water mass into a bay

Detailed hydrographic observations were made in Wakasa Bay, Japan, in August 1979 as the first of a series on the topic of bay intrusions. An anomalous water tongue, evident at a depth of 50 m, was observed to move eastward into the bay at a speed of about 10 km day⁻¹. The width of the tongue was about 20 to 30 km in agreement with the Rossby internal radius of deformation. The results of current meter measurements and the observed temporal and spatial evolution of the temperature field near the front of the anomalous water tongue have suggested that ageostrophic cross-frontal motion, in balance with the along-front acceleration, may be important in our understanding of intrusion processes.     

Petrographic and magnetic properties of tephra in a deep-sea core from the northwest Pacific

All the tephra layers sampled from a core in the northwest Pacific have both ortho-and clinopyroxenes as essential minerals, most of them containing hornblende and some of them biotite, zircon, apatite and olivine. Refractive indices of volcanic glass shards range between 1.49 and 1.53. Comparison of the refractive indices with those of artificial glass beads as well as the mineralogical composition of the tephra suggest that its sources are possibly acidic volcanoes in the Japanese island arc. Magnetic and crystallographic features of the ferromagnetic constituents in tephra have also shown that the tephra originated not from oceanic basalt but from acidic volcanoes.     

Recursive computation of oblate spheroidal harmonics of the second kind and their first-, second-, and third-order derivatives

A recursive method is developed to compute the ratios of the oblate spheroidal harmonics of the second kind and their first-, second-, and third-order derivatives. The recurrence formulas consist of three kinds: (1) fixed-degree increasing-order, (2) mixed-degree increasing-order, and (3) fixed-order decreasing-degree. The three seed values are evaluated by rapidly convergent series. The derivatives of the ratios are recursively obtained from the values and lower-order derivatives of the same harmonic order and of the same or higher degrees. The new method precisely and quickly computes the ratios and their low-order derivatives. It provides 13 correct digits of the ratios of degree as high as 262,000 and runs 20–100 times faster than the existing methods.     

New canonical variables for orbital and rotational motions

A new canonical transformation of freedom two was found. By using this, we derived three new sets of canonical variables for the orbital motion and two for the rotational motion. New canonical variables have clear physical meanings and remain well-defined in the case when the classical sets become ill-defined, for example, when the eccentricity and/or the inclination is small for the elliptic orbital motion.     

Gallium content in seaweeds

Analyses of gallium content were made by the fluorometric method on 57 samples of seaweeds which were composed of 30 species. As the result of it, the gallium content was found ranging from 0.02 to 0.64g g^–1 and the average was 0.14g g^–1 in the dried seaweeds.Generally, the gallium content in seaweeds had a close relationship to the aluminium and iron contents. The average weight ratio of Ga/Al was 3.8×10^–4 and one of Ga/Fe was 4.0×10^–4. The average Ga/Al weight ratio (3.8×10^–4) was very similar to that reported for shallow-water deposits (2.1×10^–4), but was definitely lower than that in sea water (1.5×10^–2).     

How does the ocean response to the withdrawal of water from a watergate located at the eastern boundary on a beta-plane?

The formation of the spun up region by the withdrawal of water from a watergate located in the eastern boundary in a homogeneous ocean on a beta-plane at low Rossby number is presented. The spun up region penetrates only westward from the Watergate because of the special character of the generated Rossby waves. The growth rate and the final longitudinal length of the spun up region in the dissipative system is much affected by the watergate scale in the north-south direction.The relation with the experiment ofLong (1952) and the geophysical application are presented.     

Terrestrial heat flow in the Celebes and Sulu Seas

Five heat flow measurements were made in the Asiatic Mediterranean Sea; two in the Celebes Sea and three in the Sulu Sea. The mean of all five values of 2.0 cal/cm² sec is significantly greater than the over-all mean heat flow value for the oceans and is close to the mean value for marginal seas. The measurement indicate that there may be a difference in the flow of heat through the two seas.Contribution of the Scripps Institution of Oceanography, new series.     

Orbital signals found in physical and chemical properties of bottom sediments from Lake Baikal

Physical and chemical properties of two 100 m sediment cores (BDP-93-1, 93-2) obtained from the Buguldeika saddle of Lake Baikal in the eastern Siberia and a ¹⁴C-based age scale for the core show that the core bottom is about 400000 years ago and that the changes in the sedimentological environment of the area during the interval were that comparatively coarse and high C/N ratio sediments accumulated in the lake during interglacial periods, and fine material and low C/N ratio during glacial periods. The tentative age scale suggests that the first excursion in the earth's magnetic field at about 26 m (BDP-93-1 and 93-2) from the sediment surface corresponds to the Blake event. Statistical analyses of the data-sets for the some properties show that the fluctuations have distinct periods; 20000 years, 40000 years and 100000 years, that are related to the Milankovitch parameters and support that the tentative age scale is approximately acceptable.     

Energy spectrum and pitch angle distribution of particles reflected by MHD shock waves of fast mode

To study the macroscopic acceleration process for non-thermal particles at the front of MHD shock waves, two limiting treatments, namely the “adiabatic” and the “kink” treatments have been developed. They correspond to cases of (particle gyroradius)/(width of shock transition region) ? 1 and ? 1, respectively. The effects of the acceleration process on energy and pitch angle distributions of reflected particles are examined by using each of these treatments and results are compared. It is shown that these two treatments give almost the same energy and pitch angle distribution in the case of nearly-perpendicular shock waves. In the case of nearly-parallel shock waves, the pitch angle distributions differ significantly, there being reflected particles in the adiabatic loss cone when the kink treatment is employed, while the ranges of the energy distribution for these two treatments do not differ greatly. Analytic representation for the acceleration in the adiabatic treatment is given for the later usage.