Search results for "Indian Ocean"

Design and experimental test of a low costweather buoy

2013

The importance of prevention plans based on realistic inundation scenarios was dramatically highlighted by the Indian Ocean Tsunami of 26 December 2004. But also in the Mediterranean, sea storms basin are a quite common event especially during winter months. These scenarios are generally based on numerical models of tsunami wave propagation that can become more realistic and effective when calibrated with the distribution of true data acquired by special weather buoy. In this paper we present the result of an experimental weather buoy built by DEIM of University of Palermo, that is characterized by small cost and big versatility.

UNCLOS and territorialization of the seas: the case of Indian and Pacific Oceans

2017

The 200-nautical-mile Exclusive Economic Zone created by the 1982 UNCLOS regime generates conflict in areas where the distance between opposite national coasts is less than 400 nautical miles and in marginal seas surrounded by many states and with islands. This is the case of the marginal seas in the Indian and Pacific Oceans. In particular, the EEZ regime has proved troublesome in the South China Sea, leading some authors to ask whether it has actually strengthened or undermined peace and cooperation. Does the problem really lie with UNCLOS? My purpose hereby is to explain that, in truth, UNCLOS is a milestone in the process of territorialization of the seas . The EEZ regime represents the…

Regionalizing rainfall at very high resolution over la Réunion island using a regional climate model.

2014

Abstract Regional climate models (RCMs) should be evaluated with respect to their ability to downscale large-scale climate information to the local scales, which are sometimes strongly modulated by surface conditions. This is the case for La Réunion (southwest Indian Ocean) because of its island context and its complex topography. Large-scale atmospheric configurations such as tropical cyclones (TCs) may have an amplifying effect on local rainfall patterns that only a very high-resolution RCM, forced by the large scales and resolving finescale processes, may simulate properly. This paper documents the capability of the Weather Research and Forecasting Model (WRF) RCM to regionalize rainfall…

Interannual variability of rainfall in the eastern horn of Africa and indicators of atmospheric circulation

1993

Relationships between rainfall variations in the Eastern Horn of Africa, the Southern Oscillation, and the Indian Ocean temperature and pressure surface fields are studied for the period 1932–83. Rainfall data consist of stations and regional indices calculated for three selected areas experiencing quite different rainfall patterns. The results indicate significant negative correlations between northern autumn rains in Somalia and the Southern Oscillation during the same season. These rains are also negatively correlated with pressure in the Western Indian Ocean, and positively correlated in the Eastern Indian Ocean. The reverse pattern is shown with sea-surface temperature. This agrees ver…

Climate Adjustments over Africa Accompanying the Indian Monsoon Onset

2010

Abstract Rainfall and circulation changes accompanying the Indian monsoon onset are examined, focusing on the African continent and neighboring areas. The Indian Meteorological Department official monsoon onset dates over Kerala (MOK; on average on 1 June) are used. Composites are formed at a pentad (5 days) time scale to compare pre- and postonset conditions. Climate Prediction Center (CPC) Merged Analysis of Precipitation (CMAP) data for 1979–2007 indicate that a substantial rainfall decrease over several parts of Africa is associated with MOK. Significant rainfall anomalies, after removal of the mean seasonal cycle, are found in eastern Africa and the nearby western Indian Ocean. Indian …

Element variability in the coralline alga Lithophyllum yemenense as archive of past climate in the Gulf of Aden (NW Indian Ocean)

2017

This study presents the first algal thallus (skeleton) archive of Asian monsoon strength and Red Sea influence in the Gulf of Aden. Mg/Ca, Li/Ca, and Ba/Ca were measured in Lithophyllum yemenense from Balhaf (Gulf of Aden) using laser ablation inductively coupled plasma mass spectrometry, and Mg/Ca ratio oscillation was used to reconstruct the chronology (34 y). Oscillations of element rates corresponding to the algal growth between 1974 and 2008 were compared with recorded climate and oceanographic variability. During this period, sea surface temperatures (SST) in Balhaf recorded a warming trend of 0.55 degrees C, corresponding to an increase in Mg and Li content in the algal thallus of 2.…

Wet periods along the East Africa Coast and the extreme wet spell event of October 1997

2008

Extreme wet spells affect the East Africa Coast (EAC) during March to June (long rains) and October to December (short rains). While these spells are less frequent during the short rains, some of the most extreme wet spells occur at this time of the year. The present study examined the general characteristics of the wet spells during the short rains. A detailed study of the anomalous wet spell event of October 1997, with record rainfall around Mombasa (4.0°S, 39.6°E), was also carried out. Daily rainfall for 1962-1997 and NCEP2 reanalysis data for 1979-1997 were used to study the characteristics of the wet events. A high spatial coherence is found in the rainfall over the EAC. The circulati…

Sahel droughts and Enso dynamics

1996

Correlations between summer Sahel rainfall and Southern Oscillation Index has increased during the last thirty years. At high frequency time scale (periods lower than 8 years), an intertropical Atlantic zonal divergent circulation anomaly is forced by the difference of sea surface temperature (SST) anomalies between the eastern equatorial parts of Pacific and Atlantic. This zonal connection worked well during most of the E1 Nino/Southern Oscillation (ENSO) events occurring after 1970; positive/negative SST anomalies in the eastern Pacific/Atlantic led to rainfall deficits over the whole West Africa. At low frequency time scale (periods greater than 8 years), positive SST anomalies in the In…

The marine geochemical record of the OAE 2 (~94 Ma) at high latitude: Example of the IODP Site U1516 (Exp. 369; Mentelle Basin, SW Australia)

2021

The coralline red alga Lithophyllum kotschyanum f. affine as proxy of climate variability in the Yemen coast, Gulf of Aden (NW Indian Ocean)

2014

Abstract Recent investigations have shown the potential of red coralline algae as paleoclimatic archive. A previously unexplored subfamily of coralline algae, the Lithophylloideae, was investigated from the Gulf of Aden (Balhaf, Yemen). Seasonal changes in Mg/Ca, Li/Ca and Ba/Ca composition of Lithophyllum kotschyanum f. affine were investigated by Laser Ablation-Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS). For the first time in coralline algae, the Li/Ca composition was analyzed and showed a highly significant and positive correlation with Mg/Ca and SST. Monthly algal Mg/Ca and Li/Ca variations indicate a positive correlation with sea surface temperature (SST), and sea surface…