ACTUALS PROBLEMS OF THE RESEARCH OF WORLD OCEAN LEVEL

Abstract

The features of the sea level changes and the related dynamics of the coastal zone are the subject of the discussions in the economic planning as in the regionally as in globally scale. The work’s purpose is analysis of changes of World Ocean level under the influence of different factors from the viewpoint of physical geography – the interdependence of nature of the ocean and continents, large-scale connections between oceanosphera and other elements of the Earth’s environment and evaluation of the modern established knowledge about thetendencies of the development of processes in the coastal zone. The object of research is the dynamical system of the World Ocean in the period of current climate’s changes. The subject of research is the changes of the World Ocean level for whole observation period. During the work the averaging by data series of annual level heights for 172 stations separately for the Atlantic (37 stations along the west coast and 31 – along the east), Pacific (35 and 36) andIndian (33 stations) oceans has been done. The results of researches of long-term changes of level according to different authors have shown that the observed modern sea level rise is not uniform. Our evaluation of temporal variability of the fluctuations in the level of Atlantic, Pacific and Indian oceans, and the whole World Ocean during 1880 – 2010 years period has shown their coordinated behavior. It is noted that the trend of ocean levels grows uneven with alternating stages of the weak and intense increases it. There is a slight difference in levels’ increasing in different oceans: the trend in the Atlantic Ocean was 1.85 mm·yr-1, in the Pacific and Indian oceans smaller – respectively 1.71 and 1.79 mm·yr-1 and in general for the World Ocean – 1.76 mm yr-1. The maxima of level rising in the generalized series of average annual heights of oceans (which displayed with approximately quasi decade cycles) are due to the peculiar display of the El Niño phenomenon in the Pacific Ocean. The satellite measurements of sea level have not shown increasing of the World Ocean level in 2002-2008. The falling of level on observation data in separate coastal areas of the World Ocean in the early 21st century is consistent with our estimates. The situation with the ocean level and its prognosis is not unambiguous so constant monitoring of the coastal processes is needed.