Longitude

About: Longitude is a research topic. Over the lifetime, 2260 publications have been published within this topic receiving 54988 citations. The topic is also known as: angle of longitude.

Bathymetric Atlas of the Northcentral Pacific Ocean

Abstract: : The atlas contains 41 bathymetric charts covering the NOrtheastern Pacific Ocean between 4 degrees S and 60 degrees N latitude and from 140 degrees W longitude eastward to the American continental mainland. Sea floor relief is shown by means of 200-fathom contours based on a mean sound velocity of 4800 feet/second. Where sufficient data permits, the 100-fathom and 20-fathom contours are shown. Principal sounding lines used in compilation and analysis of the sea floor relief are indicated by a subdued grey overprint on each chart. The scale of the charts is approximately 1:4,500,000. (Author)

An analytical model of interstellar gas in the heliosphere tailored to interstellar boundary explorer observations

Abstract: The stationary distribution of interstellar neutral gas in the heliosphere subject to solar gravity, solar radiation pressure, photoionization, and charge exchange is investigated analytically assuming ionization rates and radiation pressure that are proportional to R –2, where R is the heliocentric radius. The collisionless hyperbolic trajectories of the individual atoms including ionization losses are combined with Liouville's Theorem to construct the heliospheric phase-space distribution function of an interstellar gas species in the solar reference frame under the assumption that the distribution is a drifting Maxwellian at large distances from the Sun. The distribution is transformed to the Earth (essentially Interstellar Boundary Explorer (IBEX)) frame as a function of solar longitude. The expression is then tailored to the latitudinal scan of IBEX as a function of longitude using the fact that IBEX detects each atom close to perihelion in its hyperbolic orbit. The distribution is further adapted to IBEX by integrating the differential intensity over the entrance aperture solid angle of the IBEX-Lo collimator, and over energy to predict the IBEX count rate of helium. The major features of the predicted count rate are described, including a peak in longitude, a peak in latitude at each longitude, and the widths of the major peak in both latitude and longitude. Analytical formulae for these features are derived for comparison with IBEX observations in order to determine the temperature and bulk velocity of the gas in interstellar space. Based in part on these formulae, the results for helium are presented in the companion paper by Mobius et al.

On the evolution of the thermocline and subthermocline eastward currents in the Equatorial Atlantic

Abstract: [1] Eastward currents in the thermocline and subthermocline layers of the tropical Atlantic Ocean are described using observations obtained during two boreal summer cruises covering the whole equatorial basin. The analysis focuses on the eastward evolution of zonal currents in the thermocline and sub-thermocline. The Equatorial Undercurrent is not found close to the African coast in boreal summer 2000, maybe because of interannual variability. As observed in the Pacific, the South and North Equatorial Undercurrents are shown to shift poleward from west to east, and the two cruises indicate that the North Equatorial Undercurrent does not enter the Gulf of Guinea. The South and North Intermediate Countercurrents are variable with longitude and, contrarily to the observations in the eastern equatorial Pacific, are not found in the east of the Guinea basin.