A5051292058- Arctic and Antarctic ice dynamics
- Methane Hydrates and Related Phenomena
- Climate change and permafrost
- Oceanographic and Atmospheric Processes
- Geology and Paleoclimatology Research
- Cryospheric studies and observations
- Marine and coastal ecosystems
- Geological Studies and Exploration
- Marine and environmental studies
- Fish Ecology and Management Studies
- Ocean Acidification Effects and Responses
- Marine and fisheries research
- Arctic and Russian Policy Studies
- Atmospheric and Environmental Gas Dynamics
- Climate variability and models
- Aquatic Ecosystems and Phytoplankton Dynamics
- Hydrology and Sediment Transport Processes
- Mathematical and Theoretical Epidemiology and Ecology Models
- Marine Biology and Ecology Research
- Aquatic and Environmental Studies
- Food Industry and Aquatic Biology
- Indigenous Studies and Ecology
- Hydrology and Watershed Management Studies
- Microbial Community Ecology and Physiology
- Groundwater flow and contamination studies
Fisheries and Oceans Canada
2015-2025
Ocean Institute
1996-2019
American Geosciences Institute
2015
Earth Science Institute of the Slovak Academy of Sciences
2015
University of Manitoba
2015
University of Alaska Fairbanks
2013
North Pacific Marine Science Organization
1990-2008
University of Tennessee at Knoxville
2006
NOAA Pacific Marine Environmental Laboratory
2006
National Oceanic and Atmospheric Administration
2006
Salinity stratification is critical to the vertical circulation of high‐latitude ocean. We here examine control in northern seas, and potential for altering it, by considering budgets storage fresh water Arctic Ocean convective regions south. find that present‐day Greenland Iceland probably also Labrador Sea, are rather delicately poised with respect their ability sustain convection. Small variations supplied gyres from via East Current can alter or stop convection what may be a modern...
Until recently, northern Bering Sea ecosystems were characterized by extensive seasonal sea ice cover, high water column and sediment carbon production, tight pelagic-benthic coupling of organic production. Here, we show that these are shifting away from characteristics. Changes in biological communities contemporaneous with shifts regional atmospheric hydrographic forcing. In the past decade, geographic displacement marine mammal population distributions has coincided a reduction benthic...
Arctic sea-ice loss is a leading indicator of climate change and can be attributed, in large part, to atmospheric forcing. Here, we show that recent ice reductions, weakening the halocline, shoaling intermediate-depth Atlantic Water layer eastern Eurasian Basin have increased winter ventilation ocean interior, making this region structurally similar western Basin. The associated enhanced release oceanic heat has reduced formation at rate now comparable losses from thermodynamic forcing, thus...
The renewal of the deep North Atlantic by various overflows Greenland‐Scotland ridges is only one manifestation convective and mixing processes which occur in basins shelf areas to north: Arctic Ocean Greenland, Iceland, Norwegian seas, collectively called Mediterranean. traditional site ventilation for these Greenland Sea, but a growing body evidence also points as major source water. This water relatively warm saline, it appears be mixture dense, brine‐enriched with intermediate strata...
In the Arctic Ocean, phytoplankton cell sizes have decreased with warming temperatures and fresher surface waters.
We investigate basin‐scale mechanisms regulating anomalies in freshwater content (FWC) the Beaufort Gyre (BG) of Arctic Ocean using historical observations and data collected 2003–2007. Specifically, mean annual cycle interannual decadal FWC variability are explored. The major cause large BG is process Ekman pumping (EP) due to High anticyclonic circulation centered BG. seasonal liquid a result interplay between mechanical thermal (ice transformations) factors has two peaks. One peak occurs...
The spatial pattern of recent ice reduction in the Arctic Ocean is similar to distribution warm Pacific Summer Water (PSW) that interflows upper portion halocline southern Canada Basin. Increases PSW temperature basin are also well‐correlated with onset sea‐ice began late 1990s. However, increases do not correlate upstream source water northeastern Bering Sea, suggesting there another mechanism which controls these concurrent changes cover and ocean temperature. We propose a feedback whereby...
Abstract The Arctic Ocean is a fundamental node in the global hydrological cycle and ocean's thermohaline circulation. We here assess system's key functions processes: (1) delivery of fresh low‐salinity waters to by river inflow, net precipitation, distillation during freeze/thaw cycle, Pacific inflows; (2) disposition (e.g., sources, pathways, storage) freshwater components within Ocean; (3) release export into bordering convective domains North Atlantic. then examine physical, chemical, or...
Increasing global temperatures are having a profound impact in the Arctic, including dramatic loss of multiyear sea ice 2007 that has continued to present. The majority life Arctic is microbial and consequences climate-mediated changes on marine food webs, which responsible for biogeochemical cycling support higher trophic levels, unknown. We examined communities over time by using high-throughput sequencing DNA collected between 2003 2010 from subsurface chlorophyll maximum (SCM) layer...
This study was motivated by a strong warming signal seen in mooring‐based and oceanographic survey data collected 2004 the Eurasian Basin of Arctic Ocean. The source this earlier Ocean changes lies interactions between polar sub‐polar basins. Evidence suggests such are abrupt, or pulse‐like, taking form propagating anomalies that can be traced to higher‐latitudes. For example, an anomaly found eastern took ∼1.5 years propagate from Norwegian Sea Fram Strait region, additional ∼4.5–5 reach...
Acidic Ocean One consequence of the historically unprecedented level CO 2 in atmosphere that fossil fuel burning has caused, addition to a warmer climate, is higher concentrations dissolved oceans. This makes oceans more acidic, and thus less saturated with respect calcium carbonate. important ramifications for organisms have carbonate skeletons, which depend their survival on saturation state waters where they live. Yamamoto-Kawai et al. (p. 1098 ) report 2008, surface Canada Basin became...
An important yet still not well documented aspect of recent changes in the Arctic Ocean is associated with advection anomalous sub-Arctic Atlantic- and Pacific-origin waters biota into polar basins, a process which we refer to as borealization. Using 37-year archive observations (1981–2017) demonstrate dramatically contrasting regional responses atlantification (that part borealization related progression anomalies from Atlantic sector seas Ocean) pacification (the counterpart influx Pacific...
Conservation of marine biodiversity in the Beaufort Sea demands that we understand what individual organisms require their physical and geochemical environments order to survive. Specifically, how do extraordinary spatial seasonal variations ice cover, temperature, light, freshwater, turbidity, currents define unique places or times critical life? We start with traditional "bottom-up" approach, which is review strongly forcing system, from it infer resultant oceanographic regimes seasons....
Temperature, salinity, nutrients, oxygen, and halocarbon data collected in the Arctic Ocean reveal a frontal structure previously unrecognized hydrography of Canadian Basin. Samples were on 1300‐km section extending from Beaufort Sea Canada Basin to East Siberian Makarov These data, 1993 aboard CCGS Henry Larsen , lateral boundary between water masses Atlantic Pacific origin. The term “water mass assembly” is introduced describe basic arrangement or vertical stacking found Ocean, recognizing...
Potential temperature (θ) and salinity (S) data obtained along the perimeter of southern Canadian Basin north East Siberian Sea in 1993 aboard CCGS Henry Larsen show higher temperatures waters Atlantic origin than available climatological for Basin. In particular, a front is observed near Mendeleyev Ridge which separates cooler Canada from warmer Makarov The further characterized by change θ/S slope Arctic thermocline water, thermohaline intrusions (θ S reversals) within layer. idea that...
Physical and chemical data collected in the Canada Basin interior from 2003–2009 show that recent increases both Ekman convergence freshwater input, associated with sea ice retreat melt, have affected structure dynamics of upper ocean, such changes accelerated 2007–2009 when salt‐stratification below seasonal mixed layer increased about 25%. This stratification further constrains vertical heat flux winter renewal nutrients into euphotic zone. One consequence is depth nitracline (i.e. where...
Observations of salinity and oxygen isotope composition (δ 18 O) were made for the Beaufort shelf‐Mackenzie estuary waters in September 1990, just prior to ice formation, both water column April–May 1991, at end winter. These measurements are used determine apportioning fresh between its two main sources, runoff sea melt. Changes disposition seasons amounts frozen into growing sheet also derived. Two domains considered order construct a freshwater budget Mackenzie shelf, nearshore within...
Sea ice in the Canada Basin of Arctic Ocean has decreased significantly recent years, and this will likely change properties surface waters. A near‐surface temperature maximum (NSTM) at typical depths 25–35 m been previously described; however, its formation mechanisms, seasonal evolution, interannual variability have not established. Based on summertime conductivity, temperature, depth surveys year‐round Ice‐Tethered Profiler data from 2005 to 2008, we found that NSTM forms when sufficient...