TY - JOUR

T1 - Многолетние изменения крупномасштабной циркуляции в Северной Атлантике на основе спутниковых альтиметрических измерений

AU - Федоров, Александр Михайлович

AU - Кубряков, А.А.

AU - Белоненко, Татьяна Васильевна

PY - 2017/12/30

Y1 - 2017/12/30

N2 - We analyze the variability of large-scale surface geostrophic circulation in the North Atlantic Ocean using satellite altimetry for the period 1993-2015. Quantitative and qualitative evaluation of linear trends of current variability is performed. The analysis of the trends of zonal and meridional velocity components is used to understand changes in direction of the currents. It is shown that the currents weaken over the major part of the basin. Maximum weakening is observed in the Gulf Stream, where it reaches 0.017 m/s per year. For the Gulf Stream, we show that an increase in current intensity is observed mainly at its southern periphery, while at the northern periphery, there is a significant decrease in its intensity. Constant weakening is also observed in the Caribbean Current, where velocity has decreased by ~ 10% over the investigated period. We have developed a field comparison of the "first" and "last" moments, calculated using trends, as fields at the beginning of 1993 and end of 2015. Comparison of these fields allow to identify the spatial variation of large-scale circulation in the North Atlantic Ocean. By using such kind of analysis, it was found that Subtropical Gyre becomes wider in the east-west direction. North Equatorial current and Equatorial Countercurrent shift north. Also, we can note that large-scale currents change their direction almost in each part of the observed area. Direction variations occur in Antilles, Azores, and Northern-Atlantic currents.

AB - We analyze the variability of large-scale surface geostrophic circulation in the North Atlantic Ocean using satellite altimetry for the period 1993-2015. Quantitative and qualitative evaluation of linear trends of current variability is performed. The analysis of the trends of zonal and meridional velocity components is used to understand changes in direction of the currents. It is shown that the currents weaken over the major part of the basin. Maximum weakening is observed in the Gulf Stream, where it reaches 0.017 m/s per year. For the Gulf Stream, we show that an increase in current intensity is observed mainly at its southern periphery, while at the northern periphery, there is a significant decrease in its intensity. Constant weakening is also observed in the Caribbean Current, where velocity has decreased by ~ 10% over the investigated period. We have developed a field comparison of the "first" and "last" moments, calculated using trends, as fields at the beginning of 1993 and end of 2015. Comparison of these fields allow to identify the spatial variation of large-scale circulation in the North Atlantic Ocean. By using such kind of analysis, it was found that Subtropical Gyre becomes wider in the east-west direction. North Equatorial current and Equatorial Countercurrent shift north. Also, we can note that large-scale currents change their direction almost in each part of the observed area. Direction variations occur in Antilles, Azores, and Northern-Atlantic currents.

KW - Altimetry

KW - Currents

KW - Large-scale circulation

KW - The Gulf Stream

KW - The North Atlantic Ocean

KW - Trends

UR - http://www.scopus.com/inward/record.url?scp=85041072061&partnerID=8YFLogxK

U2 - 10.21046/2070-7401-2017-14-7-225-237

DO - 10.21046/2070-7401-2017-14-7-225-237

M3 - статья

AN - SCOPUS:85041072061

VL - 14

SP - 225

EP - 237

JO - СОВРЕМЕННЫЕ ПРОБЛЕМЫ ДИСТАНЦИОННОГО ЗОНДИРОВАНИЯ ЗЕМЛИ ИЗ КОСМОСА

JF - СОВРЕМЕННЫЕ ПРОБЛЕМЫ ДИСТАНЦИОННОГО ЗОНДИРОВАНИЯ ЗЕМЛИ ИЗ КОСМОСА

SN - 2070-7401

IS - 7

ER -