Portland, Maine (AP) — Ocean temperatures off the northeast United States have reached a record high.

The National Oceanic and Atmospheric Administration said Tuesday that the average sea surface temperature for the Northeast continental shelf ecosystem, from North Carolina to Maine, was a little over 50.5 degrees for the first half of 2012. The previous record high for the first six months of a year was set in 1951.

Scientists at NOAA's Northeast Fisheries Science Center say the warming temperatures impact virtually all ocean life. Atlantic cod, for instance, have been shifting northeast from their historical distribution center in recent years because of warming waters.

Scientist Kevin Friedland of the fisheries science center says it's unclear if the temperature rise will continue for the long term or is a short-term anomaly.