What's Happening Archive

July 29 - August 4: A team of NOAA and University of Washington Cooperative Institute scientists flew over Alaskan waters to conduct renewed research on Arctic ocean heat flows. Scientists deployed 30 floats from NOAA aircraft that will provide key temperature data to better understand how the Arctic ocean is warming. 

The team completed the second leg of the 2022 mission from the northernmost point of Alaska, Utqiagvik. They deployed 24 temperature profilers, Airborne eXpendable Bathy Thermographs (AXBTs), in groups of six along four different sections of an ocean slope region. AXBTs are small probes that measure ocean temperature as a function of depth as they travel through the water column. The ocean floor contains a narrow channel where warm water flows into the Arctic, eventually splitting into two flows moving left and right. The goal of this research is to measure the water temperature along this slope and determine the total heat content that each pathway is guiding, including how much of that heat moves in each direction. Determining the heat flow (in both directions) provides important information that contributes to sea ice formation and retreat, as well as effects on downstream algal blooms.

In June, the team began the first flights from Prudhoe Bay to Kotzebue and deployed eight floats that measure ocean temperature to support data collection efforts of the Distributed Biological Observatory. The team deployed 8 AXBTs that will provide critical data in this undersampled area for the next few years. 2 of the 8 floats are transmitting ocean temperature data and measurements were collected between sampling locations.    

This work is a fresh take on efforts established by the late Dr. Kevin Wood. Dr. Wood was deeply committed to understanding and communicating the nuances of science in a way that inspired and motivated people to work to mitigate climate change. To continue his legacy, special funding was brought together from NOAA PMEL, NOAA OMAO, and the University of Washington CICOES to support these flights.

An annual survey is underway to provide baseline fisheries and oceanographic data to support sustainable management of living resources in the Bering Sea and the rapidly changing US Arctic ecosystem. These surveys provide key data in understanding and monitoring events such as sea-ice loss and the cold pool and how these are impacting the Arctic ecosystem.  

This spring mooring cruise brings together scientists from NOAA’s PMEL and Alaska Fisheries Science Center, University of Washington, US Fish and Wildlife, and the University of Alaska. While aboard the NOAA Ship Oscar Dyson, the scientists will service a biophysical mooring array in the Bering Sea, collect conductivity, temperature, depth (CTD) profiles, zooplankton and ichthyoplankton samples and conduct special projects related to harmful algal blooms and zooplankton machine learning. Results from these observations and experiments will help describe important ecosystem linkages among climate, plankton, fishes, birds and mammals.  

EcoFOCI will be field testing and using several technologies this summer, including pop-up floats, a remote access sampler and a new shallow-water glider. These technologies aim to enhance shipboard and mooring research with more data collection in a fine scale region. 

NOAA’s EcoFOCI program is leading 5 research cruises this March to October in the Alaska region.

Find blog updates on the NOAA Alaska Fisheries Science Center webpage: https://www.fisheries.noaa.gov/region/alaska#science

After spending 8 months under water and ice, two of NOAA’s three Arctic-deployed pop-up floats have successfully surfaced in the Chukchi Sea and are transmitting data on temperature, pressure, photosynthetic active radiation (PAR), and chlorophyll fluorescence. These data are from measurements taken while the float is anchored to the seafloor, while it rises through the water column, and while it is trapped under the ice at the water-ice boundary.  

The two floats were initially deployed in the fall of 2020 by the scientists and crew of NOAA Ship Oscar Dyson. These are part of the 4th cohort of deployments since 2017, and the second cohort deployed in the Chukchi Sea.  The first float to surface has transmitted data from the four months it spent on the seafloor, just over a month of data from when it was trapped under ice, and about half of the photos it took while under ice. The second float has transmitted about five months of data from the seafloor, just over four months of data from under the ice along with the under-ice photos it captured, and 7 days of open ocean sea surface temperature. 

Pop-up floats provide an inexpensive method to explore a unique micro-ecosystem under floating ice. The floats collect ocean health data to help researchers better understand the rapidly changing Arctic ecosystem. They collect data during the ice-covered winter and spring months, a time during which it isn’t possible for researchers to penetrate the ice from above to study the water underneath. The water column data they collect on their rise up from seafloor to surface is essential for researchers to monitor ongoing ecosystem changes in the Arctic, such as watching for harmful algal blooms and documenting biodiversity in the environment. The floats can also help researchers measure the extent of the cold pool, an area of cold water about 30 meters deep that results from melting Arctic ice from the previous season.

NOAA PMEL began development of these floats in 2015. The float is an orange sphere equipped with sensors to measure temperature, pressure, and other ocean conditions as well as cameras to capture under ice imagery. It is deployed during the ice-free summer months and anchors to the seafloor measuring bottom-ocean conditions. It stays here collecting measurements throughout the winter and early spring. It then rises up through the water column at a pre-programmed time, in this case early March to mid-April, capturing data at various depths to create a profile of the water column. The floats are then trapped under ice when it reaches the surface, and will continue collecting data and images of conditions at the water-ice boundary. When the ice melts in mid-May and early June, the floats can emerge fully from the ice to reach the surface and begin transmitting their stored data, while continuing to monitor sea surface temperature. 

Read more about the 2020 pop-up deployments in Arctic Today and on the ITAE website.

The Beaufort Gyre in the western Arctic Ocean is the largest oceanic freshwater reservoir in the Northern Hemisphere. It has increased its freshwater content by 40% over the past two decades. The fate of the excess freshwater and how and where this water will flow into the Atlantic Ocean is important for local and global ocean conditions. A new paper in Nature Communications, researchers from the University of Washington, NOAA's Pacific Marine Environmental Laboratory and the Department of Energy Los Alamos National Laboratory, show that a historical release during 1983-1996 freshened the western Labrador Sea by as much as 0.2 parts per thousand. The results imply that a future release of the current high volume of Beaufort Gyre freshwater could even be more impactful. 

This study is the first that quantifies the fate of the Beaufort Gyre freshwater after it is released and its downstream impact. The study shows that this freshwater travels through the Canadian Archipelago to reach the Labrador Sea, rather than through the wider marine passageways that connect to seas in Northern Europe. The results are based on passive tracers implemented in a global intermediate-resolution ocean sea-ice model, which is performed at the High Performance Computing facility at Los Alamos National Laboratory. 

“The Canadian Archipelago is a major conduit between the Arctic and the North Atlantic,” said lead author Jiaxu Zhang, a UW postdoctoral researcher at the Cooperative Institute for Climate, Ocean and Ecosystem Studies who began this work at Los Alamos National Laboratory. “In the future, if the winds get weaker and the freshwater gets released, there is a potential for this high amount of water to have a big influence in the Labrador Sea region.”

The finding has implications for the Labrador Sea marine environment, since Arctic water tends to be fresher but also rich in nutrients. This pathway also affects larger oceanic currents, namely a conveyor-belt circulation in the Atlantic Ocean in which colder, heavier water sinks in the North Atlantic and comes back along the surface as the Gulf Stream. Fresher, lighter water entering the Labrador Sea could slow that overturning circulation.

“We know that the Arctic Ocean has one of the biggest climate change signals,” said co-author Wei Cheng at the UW-based Cooperative Institute for Climate, Ocean and Atmosphere Studies. “Right now this freshwater is still trapped in the Arctic. But once it gets out, it can have a very large impact."

The exact impact is unknown. The study focused on past events, and current research is looking at where today’s freshwater buildup might end up and what changes it could trigger.

Read the full University of Washington News Release.