Cells of Meridional Circulation During the Extreme Events of Antarctic Sea Ice

Author(s)

Camila Bertoletti Carpenedo ^[1] ; Tércio Ambrizzi ^[2]

Affiliation

^[1] Universidade de São Paulo. Instituto de Astronomia, Geofísica e Ciências Atmosféricas. Departamento de Ciências Atmosféricas - Brasil

^[2] Universidade de São Paulo. Instituto de Astronomia, Geofísica e Ciências Atmosféricas. Departamento de Ciências Atmosféricas - Brasil

• Document type: Journal article
• Source: Revista Brasileira de Meteorologia; v. 31, n. 3, p. 251-261, 2016-09-00.

Abstract

Abstract Because the Antarctic sea ice edge is located in a region quite sensible, under the Antarctic Polar Front, there is a great potential of sea ice variability to affect the atmospheric circulation. The objective of this study was to investigate possible relationships between the extreme events of Antarctic sea ice and the cells of meridional circulation over the Southeastern Pacific, where there is intense climate variability on various time scales. The results show that when there are extreme events of sea ice expansion in the Ross Sea sector there is cooling of the SST, which results in the surrounding atmosphere cools, increasing the thermal gradient between the edge of sea ice and the open water region. The southern pressure gradients are strengthened, which strengthens the circumpolar low pressure belt and the polar jet. So there is a strengthening of the ascending branch of the Ferrel cell over the Southern Ocean while there is a weakening in midlatitudes via conservation of mass. We observe the opposite pattern in extreme events of sea ice decrease in the Ross Sea sector and expansion in the Weddell Sea sector. (AU)

• FAPESP's process: 12/17370-2 - Atmospheric blockings associated with the extreme variability of Antarctic sea ice and impacts in South America
• Grantee: Camila Bertoletti Carpenedo
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 08/58101-9 - Impact of the Southwestern Atlantic Ocean on South American climate for the 20th and 21st centuries
• Grantee: Tercio Ambrizzi
• Support Opportunities: Research Program on Global Climate Change - Thematic Grants