статья в журнале

En

Physical Oceanography

ISSN:0928-5105
eSSN:1573-160X

2018

10.22449/1573-160X-2018-5-390-400

Discussed are the features of the oxygen and sulfide vertical distribution resulted from the expedition data obtained by Marine Hydrophysical Institute in the northern part of the Black Sea (within the economic zone of Russia) in 1995-2015. In course of the last 20 years, the upper boundary of the sulfide zone in this area, defined by the sulfide isoline 3 mu M, did not change its position in the scale of relative density and is located on sigma(t )= 16.10-16.15 kg/m(3). Closer to the northwest shelf (in the area of the Sevastopol anticyclone), the hydrogen sulfide isoline 3 mu M is slightly lifted to sigma(t) = 15.916.0 kg/m(3) ; there is a single case when its position was recorded at sigma(t) = 15.85 kg/m(3) . Position of the suboxic zone upper boundary (the threshold oxygen isoline 10 mu M) is characterized by spatial and temporal variability. During four expeditions in 2009-2013, in the region of the northwestern shelf the suboxic zone upper boundary was located, regardless of the season, within sigma(t) = 15.6-15.7 kg/m(3) . In November, 2013 in the deep sea part, the threshold oxygen isoline 10 mu M was located on sigma(t) = 15.7 kg/m(3) , whereas in November, 2015 it was considerably higher: on sigma(t) = 15.35 kg/m(3) . The change of location of the threshold oxygen isoline 10 mu M observed in 1995-2015 provides no possibility to assess unambiguously alteration of the suboxic zone thickness in the central part of the sea. Thus within the depths 1750-2000 m in the Black Sea, no significant increase of the sulfide content in 1995-2015 has been recorded.

OXYGEN, SULFIDE, SUBOXIC ZONE, HYDROGEN SULFIDE ZONE, BLACK SEA

2018-12-12 15:49:00