Volume 17. Article 1. Oceanography of Long Island Sound.

https://elischolar.library.yale.edu/bulletin_yale_bingham_oceanographic_collection/1157/thumbnail.jp

An unexpected nitrate distribution in the tropical North Atlantic at 18°N, 30°W—implications for new production

During a R.V. Meteor JGOFS-NABE cruise to a tropical site in the northeast Atlantic in spring 1989, three different vertical regimes with respect to nitrate distribution and availability within the euphotic zone were observed. Besides dramatic variations in the depth of the nitracline, a previously undescribed nose-like nitrate maximum within the euphotic zone was the most prominent feature during this study. Both the vertical structure of phytoplankton biomass and the degree of absolute and relative new production were related to the depth of the nitracline, which in turn was dependent on the occurrence/non-occurrence of the subsurface subtropical salinity maximum (S(max)). The mesoscale variability of the nitracline depth, as indicated from a pre-survey grid, and published data on the frequent occurrence of the S(max) in tropical waters suggest higher variability of new production and F-ratio than usually expected for oligotrophic oceans. The importance of salt fingering and double diffusion for nitrate transport into the euphotic zone is discussed

Métodos de muestreo y análisis y nuestro concepto de la dinámica de los océanos

In the last two decades, the increase in multi-nation, multi-ship projects has underlined the importance of intercalibration and intercomparison studies. At the same time, it is becoming obvious that with our present methods of sampling and analysis we can never hope to distinguish the variability in our sampling and analysis techniques from the variability in the universe sampled. The presence of discontinuities in many of the quantities measured suggests that our sampling grid, as maintained by oceanographic vessels, is too limited both in space and in time. Some variety of self-reporting sampling buoy is the obvious answer for physical and chemical parameters, although as yet we do not have detectors for many of the quantities of interest. Even with such buoys, it would seem unlikely that we could construct a grid of such buoys tight enough to measure the local variability of the oceans without the buoys themselves contributing to this variability. The limit finally selected for such a sampling grid will probably be some compromise between scientific capability and economic reality.En las dos últimas décadas en incremento de los proyectos multi-nacionales, con la utilización de muchos barcos ha subrayado la importancia de inter-calibración y comparación de estudios. Al mismo tiempo es obvio que con los métodos actuales de muestreo y análisis no podemos nunca esperar a distinguir la variabilidad de muestreos y análisis de la variabilidad del universo muestreado. la presencia de discontinuidades en muchas de las cantidades determinadas sugiere que nuestra zona de muestreo, realizada desde buques oceanográficos, es demasiado limitada tanto en espacio como en tiempo. La respuesta a la medida de parámetros físico-químicos sería el tipo de boya capaz de muestrear y adquirir datos, aunque no tenemos detectores para muchas de las cantidades de interés. Incluso en este tipo de boyas, no parece posible que se puede construir una red lo suficientemente tupida para medir la variabilidad local de los océanos sin que las boyas contrinuyan a esta variabilidad. El límite finalmente seleccionado por este tipo de red de muestreo radicará en un compromiso antre la capacidad y la realidad económica