US Navy transitions global ocean forecast system for public use

This Image from the Navy Global Ocean Forecast System (GOFS) portrays sea surface temperature (SST) on Jan. 15, 2014. 

The warm tropical waters can be seen to flow through the Gulf of Mexico and northward along the eastern US seaboard where the Gulf Stream separates at Cape Hatteras, off the coast of North Carolina, and flows to the east. 

This warm water "conveyer-belt" alters the ice cover across the north Atlantic. 

Without the ocean transport of heat, global climate and weather would be dramatically changed. 

Credit: U.S. Naval Research Laboratory-Oceanography Division

The U.S. Naval Research Laboratory (NRL) and the National Center for Environmental Prediction (NCEP) within the National Ocean and Atmospheric Administration (NOAA) have entered into a formal agreement that results in NCEP using Navy developed global ocean forecast model technology to make environmental ocean forecasts for public use.

"Development of an advanced global ocean prediction system has been a long-term Navy interest," said Dr. Gregg Jacobs, head, NRL Ocean Dynamics and Prediction Branch.

"This use of Navy developed systems for global ocean forecasting represents dual use technology that will benefit civilian interests and is an excellent example of the cutting edge research that is enabled through Navy sponsored investments."

The Navy has had requirements for predicting the ocean environment for its purposes including estimating acoustic propagation, placement of sonar arrays, determining currents for mine drift and burial, drift for search and rescue, and safety of operations on and under the ocean surface.

NRL has enabled Navy operational ocean prediction of tactically relevant information.

To accomplish this task, Jacobs says three critical components are necessary to predict the open ocean environment.


Ocean Circulation Models - Gregg Jacobs.

"The first is access to satellite observations that measure precise sea surface height, sea surface temperature and ice concentration with in situ observations from public sources and Navy ships; second, numerical models representing the dynamical processes capable of understanding the physics of the ocean and numerical methods for efficiently representing those physics; and lastly, the third critical component is the technology to correct the numerical models using the observations through data assimilation."

The new agreement will allow NCEP to use software developed by NRL to assimilate data necessary to maintain daily forecast accuracy that enables safe, at-sea operations, hazard mitigation, resource management, and emergency response.

"This is an example of complementary missions across agencies that through coordinated application leads to protecting our service personnel, who ensure the high seas are safe, and protecting our resources and citizens at home." Jacobs said.

NASA: NOAA Arctic Cyclone Breaks Up Sea Ice

The storm cut off a large section of sea ice north of the Chukchi Sea and pushed it south to warmer waters that made it melt entirely. It also broke vast extensions of ice into smaller pieces more likely to melt.

NASA has released the following animation which shows how the winds of a large Arctic cyclone broke up the thinning sea ice cover of the Arctic Ocean in early August 2012.

According to NASA the storm likely contributed to the ice cap's shrinking to the smallest recorded extent in the past three decades.

The frozen cap of the Arctic Ocean likely reached its annual summertime minimum extent and broke a new record low on Sept. 16, the National Snow and Ice Data Center (NSIDC) at the University of Colorado in Boulder has reported.

Analysis of satellite data by NASA and the NASA-supported NSIDC showed that the sea ice extent shrunk to 1.32 million square miles (3.41 million square kilometers), or 293,000 square miles less than the previous lowest extent in the satellite record, set in mid-September, 2007.

Arctic Cyclone Breaks Up Sea Ice.

"Climate models have predicted a retreat of the Arctic sea ice; but the actual retreat has proven to be much more rapid than the predictions," said Claire Parkinson, a climate scientist at NASA Goddard Space Flight Center, Greenbelt, Md.

"There continues to be considerable inter-annual variability in the sea ice cover, but the long-term retreat is quite apparent."

This year, the cyclone formed off the coast of Alaska and moved on Aug. 5 to the center of the Arctic Ocean, where it churned the weakened ice cover for several days.

"The storm definitely seems to have played a role in this year's unusually large retreat of the ice," Parkinson said.

"But that exact same storm, had it occurred decades ago when the ice was thicker and more extensive, likely wouldn't have had as prominent an impact, because the ice wasn't as vulnerable then as it is now."

Sea ice data courtesy of the Defense Meteorological Satellite Program (DMSP). Wind data courtesy of the National Centers for Environmental Prediction (NCEP).

Visualization credit: Scientific Visualization Studio/NASA Goddard Space Flight Cente