skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

Explore Research Products in the PAR
It may take a few hours for recently added research products to appear in PAR search results.


  • NSF Public Access
  • Search Results
  • Changes at the Edge: Trends in sea ice, ocean temperature, and ocean color at the Northwest Atlantic/Southern Arctic interface
Title: Changes at the Edge: Trends in sea ice, ocean temperature, and ocean color at the Northwest Atlantic/Southern Arctic interface
Spatial and temporal trends of remotely sensed sea-ice cover, sea surface temperatures, chlorophyll-a concentration and primary production in the Baffin Bay, Davis Strait and Labrador Sea were analyzed for the 1998–2017 period. We found spatial variability in the trends of these cryospheric, biologic and oceanographic phenomena. For example, in the northern Baffin Bay, we observed decreases in annual sea-ice persistence, yet increases along the Labrador Sea-ice edge during winter, with the latter having significant correlations with broader atmospheric patterns. In general, we observed increases in summer sea surface temperatures across the study region, except a small area of cooling along the southern Greenlandic coast. We also found significant negative trends in April chlorophyll-a and primary production followed by significant positive trends for both biological phenomena in May, owing to anomalously high values in 2014 and 2015. Notably, we found a significant positive correlation between days of monthly sea ice presence in April with May primary production quantities. Finally, we found a significant positive trend in total annual primary production over the study period. This novel finding suggests an important relationship between the timing of breakup along the sea-ice edge and peaks in biological production.  more » « less
Award ID(s):
1702137
PAR ID:
10237302
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Annals of Glaciology
ISSN:
0260-3055
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. ; ; ; ; ; (, PLOS ONE)
    Westergaard-Nielsen, Andreas (Ed.)
    Massive declines in sea ice cover and widespread warming seawaters across the Pacific Arctic region over the past several decades have resulted in profound shifts in marine ecosystems that have cascaded throughout all trophic levels. The Distributed Biological Observatory (DBO) provides sampling infrastructure for a latitudinal gradient of biological “hotspot” regions across the Pacific Arctic region, with eight sites spanning the northern Bering, Chukchi, and Beaufort Seas. The purpose of this study is two-fold: (a) to provide an assessment of satellite-based environmental variables for the eight DBO sites (including sea surface temperature (SST), sea ice concentration, annual sea ice persistence and the timing of sea ice breakup/formation, chlorophyll- a concentrations, primary productivity, and photosynthetically available radiation (PAR)) as well as their trends across the 2003–2020 time period; and (b) to assess the importance of sea ice presence/open water for influencing primary productivity across the region and for the eight DBO sites in particular. While we observe significant trends in SST, sea ice, and chlorophyll- a /primary productivity throughout the year, the most significant and synoptic trends for the DBO sites have been those during late summer and autumn (warming SST during October/November, later shifts in the timing of sea ice formation, and increases in chlorophyll- a /primary productivity during August/September). Those DBO sites where significant increases in annual primary productivity over the 2003–2020 time period have been observed include DBO1 in the Bering Sea (37.7 g C/m 2 /year/decade), DBO3 in the Chukchi Sea (48.0 g C/m 2 /year/decade), and DBO8 in the Beaufort Sea (38.8 g C/m 2 /year/decade). The length of the open water season explains the variance of annual primary productivity most strongly for sites DBO3 (74%), DBO4 in the Chukchi Sea (79%), and DBO6 in the Beaufort Sea (78%), with DBO3 influenced most strongly with each day of additional increased open water (3.8 g C/m 2 /year per day). These synoptic satellite-based observations across the suite of DBO sites will provide the legacy groundwork necessary to track additional and inevitable future physical and biological change across the region in response to ongoing climate warming. 
    more » « less
  2. ; ; (, Remote Sensing)
    The offshore transport of Greenland coastal waters influenced by freshwater input from ice sheet melting during summer plays an important role in ocean circulation and biological processes in the Labrador Sea. Many previous studies over the last decade have investigated shelfbreak transport processes in the region, primarily using ocean model simulations. Here, we use 27 years of surface geostrophic velocity observations from satellite altimetry, modified to include Ekman dynamics based on atmospheric reanalysis, and virtual particle releases to investigate seasonal and interannual variability in transport of coastal water in the Labrador Sea. Two sets of tracking experiments were pursued, one using geostrophic velocities only, and another using total velocities including the wind effect. Our analysis revealed substantial seasonal variability, even when only geostrophic velocities were considered. Water from coastal southwest Greenland is generally transported northward into Baffin Bay, although westward transport off the west Greenland shelf increases in fall and winter due to winds. Westward offshore transport is increased for water from southeast Greenland so that, in some years, water originating near the east Greenland coast during summer can be transported into the central Labrador Sea and the convection region. When wind forcing is considered, long-term trends suggest decreasing transport of Greenland coastal water during the melting season toward Baffin Bay, and increasing transport into the interior of the Labrador Sea for water originating from southeast Greenland during summer, where it could potentially influence water column stability. Future studies using higher-resolution velocity observations are needed to capture the role of submesoscale variability in transport pathways in the Labrador Sea. 
    more » « less
  3. (, American Geophysical Union 2024 Fall Meeting)
    Recent low sea ice extents across Distributed Biological Observatory (DBO) sites in the northern Bering, Chukchi, and Beaufort seas of the Pacific Arctic region have been due to both later fall/winter freeze-up and earlier spring breakup, which in turn have important cascading impacts on the physical, biological, and biogeochemical state of the overall marine environment throughout this region. Satellite observations of the DBO sites that span across a large latitudinal gradient (~62–72°N) include sea surface temperature (SST), sea ice concentration, annual sea ice persistence and the timing of sea ice breakup/formation, chlorophyll-a concentrations, and primary productivity. While we observe significant trends in SST, sea ice, and chlorophyll-a/primary productivity throughout the year, the most significant and synoptic trends for the DBO sites have been those during late summer and autumn (warming SST during October/November, later shifts in the timing of sea ice formation, and increases in chlorophyll-a/primary productivity during August/September). Measurements of the transmittance of solar radiation through the ocean water column is also one of the critical elements for understanding the potential implications of these recent shifts in sea ice, including impacts on primary production, damaging effects of UV radiation on phytoplankton, photodegradation of dissolved organic matter, and upper ocean heating. Field-based observations of downwelling irradiance and upwelling radiance profiles in the top ~30-50 meters of ocean waters are also presented, collected at discrete stations across DBO sites 1–5 in the northern Bering and Chukchi Seas. Profiles were collected during July 2018, 2019, 2021, 2022, and 2023 as part of the DBO program onboard the Canadian Coast Guard Ship (CCGS) Sir Wilfrid Laurier, and represent a first time series of optical measurements across these DBO sites. Continued monitoring of the transmittance of solar radiation through the water column at these DBO sites will be crucial for understanding changes in the underwater light field as the duration of the open water season continues to lengthen with declining seasonal sea ice cover. 
    more » « less
  4. ; ; ; ; (, Journal of Geophysical Research: Oceans)
    Abstract Baffin Bay is the travel destination of most icebergs calving from west Greenland. They commonly follow the bay's cyclonic circulation and might end up far south along the coast of Newfoundland and Labrador, where many shipping routes converge. Given the hazard that icebergs pose to marine transportation, understanding their distribution is fundamental. One of the forces driving iceberg drift arises from the presence of sea ice. Observations in the Southern Ocean indicate that icebergs get locked in thick and concentrated sea ice. We present observations that support the occurrence of this sea ice locking mechanism (SIL) in Baffin Bay as well. Most iceberg models, however, represent the sea ice force over an iceberg as a simple drag force. Here, we implement a new parameterization in the iceberg module of the Nucleus for European Modeling of the Ocean (NEMO‐ICB) to represent SIL. We show that, by using this new parameterization, icebergs are more likely to travel outside of the Baffin Island Current during winter, which is supported by satellite observations. There is a slight improvement in the representation of iceberg severity along the coast of Newfoundland and Labrador and a slight shift of iceberg melt toward this region and Lancaster Sound/Hudson Strait. Although the impacts of icebergs on sea ice are still not represented, and targeted observations are needed for model calibration regarding sea ice concentration thresholds from which icebergs get locked, we are confident that this model improvement takes iceberg modeling one step forward toward reality. 
    more » « less
  5. ; ; ; ; ; ; ; ; ; ; et al (, Geophysical research letters)
    Baffin Bay exports Arctic Water to the North Atlantic while receiving northward flowing Atlantic Water. Warm Atlantic Water has impacted the retreat of tidewater glaciers draining the Greenland Ice Sheet. Periods of enhanced Atlantic Water transport into Baffin Bay have been observed, but the oceanic processes are still not fully explained. At the end of 2010 the net transport at Davis Strait, the southern gateway to Baffin Bay, reversed from southward to northward for a month, leading to significant northward oceanic heat transport into Baffin Bay. This was associated with an extreme high in the Greenland Blocking Index and a stormtrack path that shifted away from Baffin Bay. Thus fewer cyclones in the Irminger Sea resulted in less frequent northerly winds along the western coast of Greenland, allowing anomalous northward penetration of warm waters, reversing the volume and heat transport at Davis Strait. 
    more » « less
  • Citation Formats
  • MLA
  • APA
  • Chicago
  • BibTeX
  • Save / Share this Record
  • Send to Email