 |
| Titel |
Mixed layer variability and chlorophyll a biomass in the Bay of Bengal |
| VerfasserIn |
J. Narvekar, S. Prasanna Kumar |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1726-4170
|
| Digitales Dokument |
URL |
| Erschienen |
In: Biogeosciences ; 11, no. 14 ; Nr. 11, no. 14 (2014-07-22), S.3819-3843 |
| Datensatznummer |
250117519
|
| Publikation (Nr.) |
 copernicus.org/bg-11-3819-2014.pdf |
|
|
|
|
|
| Zusammenfassung |
| The mixed layer is the most variable and dynamically active part of the
marine environment that couples the underlying ocean to the atmosphere and
plays an important role in determining the oceanic primary productivity. We
examined the basin-scale processes controlling the seasonal variability of
mixed layer depth in the Bay of Bengal and its association with chlorophyll
using a suite of in situ as well as remote sensing data. A coupling between
mixed layer depth and chlorophyll was seen during spring intermonsoon and
summer monsoon, but for different reasons. In spring intermonsoon the
temperature-dominated stratification and associated shallow mixed layer makes
the upper waters of the Bay of Bengal nutrient depleted and oligotrophic. In
summer, although the salinity-dominated stratification in the northern Bay of
Bengal shallows the mixed layer, the nutrient input from adjoining rivers
enhance the surface chlorophyll. This enhancement is confined only to the
surface layer and with increase in depth, the chlorophyll biomass decreases
rapidly due to reduction in sunlight by suspended sediment. In the south,
advection of high salinity waters from the Arabian Sea and westward
propagating Rossby waves from the eastern Bay of Bengal led to the formation
of deep mixed layer. In contrast, in the Indo–Sri Lanka region, the shallow
mixed layer and nutrient enrichment driven by upwelling and Ekman pumping
resulted in chlorophyll enhancement. The mismatch between the nitrate and
chlorophyll indicated the inadequacy of present data to fully unravel its
coupling to mixed layer processes. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|