The Southern Ocean encircles the continent of Antarctica and extends northward to which latitude?

The correct option is

60 degrees south latitude

Explanation

The Southern Ocean, also known as the Antarctic Ocean, comprises the southernmost waters of the World Ocean. While its boundaries have historically varied, the modern definition relies on specific latitudinal limits established to distinguish it from the Atlantic, Indian, and Pacific Oceans.

Detailed Analysis

The International Hydrographic Organization (IHO) redefined the limits of the oceans in 2000. According to this standard:

• The Southern Ocean completely encircles the continent of Antarctica.
• Its northern limit is defined as 60 degrees south latitude.
• This boundary was chosen to encompass the unique oceanographic characteristics of the region, such as the Antarctic Circumpolar Current, although the current itself fluctuates geographically.
• The 60°S latitude also aligns with the jurisdiction of the Antarctic Treaty System.

Therefore, options 40 degrees south latitude, 50 degrees south latitude, and 70 degrees south latitude are incorrect as they do not correspond to the officially recognized northern boundary.

Key Takeaway: The Southern Ocean is defined as the waters extending from the coast of Antarctica northward to 60°S latitude.