On average 1–2 tropical cyclones form over the Arabian Sea each year, and few of these storms are intense enough to be classified as very severe or super cyclonic storms. As such, few studies have explicitly identified the seasonal to interannual changes in environmental conditions that are associated with Arabian Sea tropical cyclogenesis. However, over the last 30 yr several intense Arabian s...

[1] Sr and Nd isotopic composition of silicate fractions of sediments have been measured in two well dated gravity cores from the eastern Arabian Sea archiving a depositional history of ∼29 and ∼40 ka. The Sr/Sr and "Nd in the northern core (SS‐3104G; 12.8°N, 71.7°E) ranges from 0.71416 to 0.71840 and −8.8 to −12.8; these variations are limited compared to those in the southeastern core (SS‐310...

Ammonia-oxidizing archaea (AOA) have been reported at high abundance in much of the global ocean, even in environments, such as pelagic oxygen minimum zones (OMZs), where conditions seem unlikely to support aerobic ammonium oxidation. Due to the lack of information on any potential alternative metabolism of AOA, the AOA community composition might be expected to differ between oxic and anoxic e...

We computed high-resolution (1 latitude × 1 longitude) seasonal and annual nitrous oxide (N2O) concentration fields for the Arabian Sea surface layer using a database containing more than 2400 values measured between December 1977 and July 1997. N2O concentrations are highest during the southwest (SW) monsoon along the southern Indian continental shelf. Annual emissions range from 0.33 to 0.70 ...

[1] Monthly oxygen budgets for the subsurface Arabian Sea (100–1000 m) are constructed on the basis of Modular Ocean Model and recently collected oxygen data. The model results are in agreement with the observed pattern. The model results revealed that oxygen minimum zone (OMZ) in the Arabian Sea is regulated largely by physical processes in association with biogeochemical cycling of oxygen. Th...

Coastal versus open-ocean denitrification in the Arabian Sea S. W. A. Naqvi, H. Naik, A. Pratihary, W. D’ Souza ∗ , P. V. Narvekar, D. A. Jayakumar ∗∗ , A. H. Devol, T. Yoshinari, and T. Saino National Institute of Oceanography, Dona Paula, Goa 403 004, India School of Oceanography, University of Washington, Seattle, WA 98195, USA Wadsworth Center, New York State Department of Health, PO Box 50...

The Arabian Sea harbours one of the three major oxygen minimum zones (OMZs) in the world’s oceans, and it alone is estimated to account for∼10–20 % of global oceanic nitrogen (N) loss. While actual rate measurements have been few, the consistently high accumulation of nitrite (NO−2 ) coinciding with suboxic conditions in the central-northeastern part of the Arabian Sea has led to the general be...

This work presents a shallow water ambient noise analysis and modeling effort in the Arabian Sea. Real ambient noise recording at very shallow depths has been analyzed for two environmentally unique periods when the sound velocity profile and the wind conditions present distinct characteristics. Ambient noise data were collected for January and March in the shallow water of Arabian Sea between ...

A dust aerosol model was developed and its performance validated against pre-INDOEX measurements. This model was incorporated in the NCMRWF T80 global model. A five-day integration was performed with the assumption that light mineral dust is present over Arabian Sea. Mean shortwave dust forcings were computed from the forecast. In general, at surface, a negative dust forcing was noted. At the t...

Tropical cyclones over the Arabian Sea in the pre-monsoon season (May–June) have intensified since 1997 (ref. 1, Fig. 1a) owing to significant reductions in storm-ambient vertical wind shear (VWS) in the troposphere; these reductions have decreased on average by about 3m s from the pre-1997 epoch (1979–1997) to the recent epoch (1998–2010). The authors attribute the reduction of premonsoon VWS ...