North Brazil Current
The North Brazil Current (NBC) is a warm water
Track
The current begins around 10°S and 31°W, where the split of the South Equatorial Current becomes apparent. The split is forced once the continental shelf begins, and happens quite abruptly. At this point, the current moves quite quickly at 21-23 Sv. Around 5°S, it merges with a northern branch of the South Equatorial Current (SEC) and increases its volume to 37 Sv, with its peak between 100m and 200m deep. Here, the current is at its maximum extent of about 300 kilometers wide. The current continues to about 7°N and 52°W, where it becomes the Guiana Current.[2]
Characteristics
The general speed of the current is between 60 and 100 centimeters per second. A peak recorded speed of 110 centimeters per second was recorded about 100 m below the surface of the ocean, in the vicinity of where the NBC merges with the SEC. Average temperatures are in the range of 22 °C to 28.5 °C, and tend to be warmest during the northern hemisphere's summer.[3]
The strength of the current is dependent on the season. During the northern hemisphere's spring, there is a minimum of 13 Sv in the current, which jumps to 36 Sv as the easterlies strengthen. The average is about 26 Sv for the whole year.[4]
The average
The depth of the NBC is dependent on the depth of the
North Brazil Current Rings
From July to February, it is quite common for the current to separate from the coast and curve back into itself. Since the current can be quite large, it is easy for large anticyclonic rings to generate, which separate from the main mass of the current and move northwestward with the prevailing winds.[7] The mean diameter of the rings is about 300 kilometers, and move between 8 and 30 kilometers per day depending on the strength of the flow surrounding the ring. The rings are relatively shallow and move typically less than 1 Sv of water. The rings will eventually spin down after 100 days. Most rings make it to within the vicinity of the Caribbean Sea, and it is even possible for some to move into the lake, given that they are small enough to fit between the Lesser Antilles.[2]
References
- .
- ^ .
- ^ .
- .
- S2CID 58924049.
- .
- .
See also
- Ocean current
- Oceanic gyres
- Physical oceanography