A
Digital AtlasThe main task of this project
is to provide a digital atlas of the physical oceanographic
properties of the Black Sea based on a comprehensive update
of available historical hydrological data sets. The atlas,
which will be made available without restriction on a CD-ROM,
will contain gridded climatology statistics, seasonal and
long-term variability assessments, and a hydrological database
that exceeds 100,000 hydrographic casts with a software interface
for convenient access to the primary data. This database will
be the most complete hydrological data set for the Black Sea
in existence.
Studies in Decadal and Inter-Annual
Variability This project will provide for the first
time estimates of decadal and inter-annual variability in
the Black Sea, not only in the coastal zone, but also in deep-water
regions. Hydrological data will be used to compute reliable
and detailed climatological parameters that describe oceano-graphic
features including the thermohaline, cold intermediate layer,
sound speed structure, vertical stability, and circulation
patterns. Long-term signals in the Black Sea can be understood
in terms of the response of an enclosed sea to changes in
the Europe-North Atlantic climate system. This response can,
in turn, influence processes in the interconnected basin of
the Eastern Mediterranean through water exchange. This research
will estimate the degree of confidence and level of uncertainty
associated with such long-term signals.
Background The Black Sea has
been an object of exploration and intensive scientific research
for a historically long period of time. The basin attracts
oceanographers because of a unique hydrographic structure
originating from a combination of restricted exchange with
the Mediterranean and a large fresh water input. The resulting
sharply-stratified, two-layer structure prevents deep convective
mixing of the basin interior and results in the formation
of a permanent anoxic pool beneath the pycnocline. A series
of climatological hydrological atlases, reflecting the available
data, were published in the thirty year period beginning in
the 1950's. The existing Marine Hydrophysical Institute (MHI)
Black Sea data set exceeds 100,000 hydrographic casts and
is two times larger than the one used in the last published
atlas. This set provides an opportunity to estimate climatological
fields more reliably and in greater detail than ever before.
These fields not only have intrinsic value but also are the
basis for investigations of climate processes on scales ranging
from the mesoscale to the decadal.
Regard for a Fragile Ecosystem
During the last decade appreciable political and economical
changes have occurred in the Black Sea region. Two examples
are the rise of the new independent states and the intensification
of oil tanker use in the Sea. These changes have had a profound
influence on the Black Sea ecosystem. Recently, it was found
the ecosystem is under serious threat from environmental changes
resulting from increased discharge of nutrients and pollutants,
land-based activities, and extensive fisheries activity. Ecosystem
changes, manifested in enhanced eutro-phication and reduction
in biodiversity, have stimulated a number of joint international
research projects. Several of these projects involved a substantial
physical oceano-graphy and data collection component but the
aim was not to compute a new climatology or to estimate long-term
trends from available data. In addition, the data sets have
been somewhat limited. There is a clear need for the construction
of a new, comprehensive database.