CAROL STEPIEN: We have Phyllis Stabeno speaking on the Bering Sea Ecosystem, Dramatic Shifts in the Bering Sea and its Impacts on Fisheries. 

PHYLLIS STABENO: Good morning. As Carol said, my name is Phyllis Stabeno. Janet Duffy-Anderson, who is in the back, from the Alaska Fisheries Science Center and I are the co-leads of the EcoFOCI program. EcoFOCI is an interdisciplinary cross-line office program. Our focus is in Alaskan waters. 

Alaska is huge. 80% of the US coastline is found here. Over 50%, by area, of the continental shelves are found here. This is a very large area. FOCI is an extensive field operation. We participate in six or more cruises a year, totaling 100 days at sea. 

In addition, we maintain 10 long-term biophysical moorings in these waters. These include NOAA's only long-term mooring in the US Arctic. This presentation focuses on the Bering Sea shown here. The Bering Sea is a very rich ecosystem. NOAA has many missions here. The two that are really pertinent to EcoFOCI are it manages the vast and valuable fisheries resources here. And it also protects the large number of marine mammals that exist here. 

EcoFOCI collects data, analyzes the data, integrates it with other ecosystem data, and provides that data to managers, both federal and state, and to many stakeholders, including local communities, the fishing industry, et cetera. So the Bering Sea is interesting. It consists almost equally of a large eastern shelf and a basin. And our focus is on this eastern shelf. 

Sea ice dominates this system. It sets up the whole ecosystem. In the summer, it's ice free. In the winter, frigid winds out of the north force the ice south. And in cold years, sea ice can cover the entire eastern Bering Sea shelf. Shown here are the time series that we have-- been used as an index of how much ice we had. The last decade has shown extremes. 

2012 had the highest ice extent in the satellite era. Six years later, we had the lowest ice extent we've ever seen. Shown on the right is a maximum ice extent. From 2018 and 2012-- the difference between these is half a million square kilometers, larger than the State of California. So underneath this ice, the water column gets very cold-- -1.7. In the summer, when this retreats-- when the ice retreats, it forms a surface mix layer. 

And this surface mix layer insulates the bottom and keeps these temperatures at the bottom cold throughout the summer. This is called the cold pool when the temperatures are below 2 degrees. Showing on the right-- on the left, pardon me-- is the iciest part of the cold pool extent. You see 2012, it's huge, 2018, almost non-existent. This data comes from our colleagues at Fisheries. [INAUDIBLE] provided this. 

The interesting part is the modeling group of EcoFOCI, its predictions of the extent of the cold pool in 2050. What we're seeing in 2018 is a sneak preview of what the middle of the century is expected to look like. So why is the cold pool important? 

It's a barrier-- it forms a barrier to adult fish, who don't like the cold temperatures below about 1 degree. It's a refuge for young of the year, who can tolerate them. 

And it's a corridor for arctic species to come to the southern Bering Sea. So this is data from M8, which is our northernmost mooring in the Bering Sea. And it's 15 years of data. You can see all the gray lines, all the early years. Temperatures never got above two degrees. The last three years, we're beginning to see these warm temperatures intrude on this system, with 2018 reaching over 4 degrees, which was not expected until late in the century. 

This was a shocking event to everybody who works up there. So I'd like to shift a little bit. As I said, we have an extensive field project. But we also have this modeling group. And shown here in the upper right is a hindcast of the cold pool extent. It provides us information on mechanisms and it gives the short-term predictions. But one of the most important parts of the modeling components that we do is we collaborate with our colleagues in Fisheries. 

Shown below is the prediction for pollock-- the stock. Using the ROMS model was forced-- downscaled by the large Arctic models. And what we see is a real decrease in pollock. Pollock is important to the sea. This is a primary forage fish. And it provides about 1/3 of the revenue for the $2 billion industry that is the fishing industry of the Bering Sea. Shown in the top here is what happens when pollock [INAUDIBLE]? Cold pool is shown in pink. 

And in 2010, extensive ice sheet-- all the pollock are on this slope. 2018, basically no cold pool-- they spread out. This means they spread their intermingling. But at the end of the year, pollock have a dreadful habit of eating their children-- 

[LAUGHTER]

Bad habits. 

And so this year, a very different arrangement. The pollock went to the Arctic. The Russians commercially fished pollock last year. These changes we've seen have huge impacts from nutrient supply to massive bird die-offs and to communities. The data PMEL, or EcoFOCI, provides provides information to all of these groups to help to manage this ecosystem. Thank you. 

[APPLAUSE]