Mean Sea Level Variability of the Oman Sea and its response to monsoon and the North Atlantic Oscillation index from Tide Gauge measurements

Sea level analysis along the Northern Coast of the Oman Sea has been investigated on the basis of tide gauge measurements. Meteorological parameters, along with monsoon and NAO indices are used to study the response of sea level to local and global forcing.  The relation between sea level and forces are examined. The low correlation coefficient (-0.35) between sea level and atmospheric pressure at Chabahar indicates that the response to atmospheric pressure is not an inverse barometric. The nature of local inverse barometric effects are examined through a series of statistical models. Analysis between sea level and atmospheric pressure reveals a significant coherence, which means that the Oman Sea mean level responds to atmospheric pressure as an inverse barometer. One can notice that the   between atmospheric pressure and mean sea level is due to alongshore wind stress forcing and is consistent with that expected from Ekman dynamics. The four EOF modes capture 87.16% for the x-component and 94.70% for the y-component of the total variance and are statistically significant.  Linear regression and ARIMA model forecasts were fitted to sea level and compared to the actual data. Even though both models gave similar results, the ARIMA model performed considerably bette

An estimate of the surface heat fluxes transfer of the Persian Gulf with the overlying atmosphere

The ocean heat exchange process is a key mechanism in climate variations over a broad time – scale. In this study, the long–term mean surface heat fluxes over the Persian Gulf have been estimated by the empirical relations using data derived from National Oceanic and Atmospheric Administration (NOAA). The basin-averaged annual mean values of heat transfer due to solar radiation, sensible heat flux, long-wave radiation flux and latent fluxes are about 219,−14, −75 and −136, respectively. Therefore, the long – term annual mean net heat flux is about −6 W m−2 (negative sign means upward heat flux) and shows a very good agreement with the direct measured advective value through the Hormuz Strait. The spatial distribution of the surface heat fluxes, which has not been investigated before, show relatively large spatial variation in latent heat flux. The annual mean net heat flux spatial distribution varies from about −30 to 10 W m−2, with greatest heat loss in southeastern and northwestern regions of the Gulf. In mid – winter (January), the northern region along the Iranian coast loses heat (about 20–80 W m−2) but southern and northwestern shallow regions gain heat (about 15 W m−2) from the atmosphere. In mid-summer (July) the spatial variation in net heat flux is weak and is positive at most all over the Gulf