A5019451992- Arctic and Antarctic ice dynamics
- Oceanographic and Atmospheric Processes
- Methane Hydrates and Related Phenomena
- Geology and Paleoclimatology Research
- Geological Studies and Exploration
- Cryospheric studies and observations
- Climate variability and models
- Climate change and permafrost
- Microplastics and Plastic Pollution
- Geophysics and Gravity Measurements
- Marine and coastal ecosystems
- earthquake and tectonic studies
- Marine and environmental studies
- Arctic and Russian Policy Studies
- Atmospheric and Environmental Gas Dynamics
- Recycling and Waste Management Techniques
- Seismology and Earthquake Studies
- Marine Biology and Environmental Chemistry
- Geological formations and processes
- Mercury impact and mitigation studies
- Environmental Monitoring and Data Management
- Geological and Geophysical Studies
- Marine and fisheries research
- Distributed and Parallel Computing Systems
- Earthquake and Tsunami Effects
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung
2014-2024
University of Bremen
2023
Australian Wool Innovation (Australia)
2020
CMCC Foundation - Euro-Mediterranean Center on Climate Change
2016
Abstract. The Finite Element Sea Ice-Ocean Model (FESOM) is the first global ocean general circulation model based on unstructured-mesh methods that has been developed for purpose of climate research. advantage models their flexible multi-resolution modelling functionality. In this study, an overview main features FESOM will be given; sensitivity experiments a number specific parameter choices explained; and directions future developments outlined. It argued sufficiently mature to explore...
Recent studies have shown that despite its remoteness, the Arctic region harbors some of highest microplastic (MP) concentrations worldwide. Here, we present results a sampling campaign to assess vertical distribution MP particles (>11 μm) at five stations HAUSGARTEN observatory. Water column samples were taken with large volume pumps by filtering 218-561 L seawater two four depth strata (near-surface, ∼300 m, ∼1000 and above seafloor), sediment multiple corer. in water ranged between 0 1287...
Abstract Substantial changes have occurred in the Arctic Ocean last decades. Not only sea ice has retreated significantly, but also ocean at middepth showed a warming tendency. By using simulations we identified mechanism that intensifies upward trend heat supply to through Fram Strait. The reduction export Strait induced by decline increases salinity Greenland Sea, which lowers surface height and strengthens cyclonic gyre circulation Nordic Seas. Atlantic Water volume transport Seas is...
Abstract Eddy driven recirculation of Atlantic Water (AW) in the Fram Strait modifies amount heat that reaches Arctic Ocean, but is difficult to constrain ocean models due very small Rossby radius there. In this study, we explore effect resolved eddies on AW circulation a locally eddy‐resolving simulation global Finite‐Element‐Sea ice‐Ocean Model (FESOM) integrated for years 2000–2009, by focusing seasonal cycle. An eddy‐permitting serves as control run. Our results suggest resolving local...
Abstract A new global climate model setup using FESOM2.0 for the sea ice‐ocean component and ECHAM6.3 atmosphere land surface has been developed. Replacing FESOM1.4 by promises a higher efficiency of compared to its predecessor. The allows long‐term integrations locally eddy‐resolving ocean. Here it is evaluated in terms (1) mean state drift under preindustrial conditions, (2) fidelity simulating historical warming, (3) differences between coarse ocean configurations. results show that...
The ocean moderates the world's climate through absorption of heat and carbon, but how much carbon will continue to absorb remains unknown. North Atlantic Ocean west (Baffin Bay/Labrador Sea) east (Fram Strait/Greenland Greenland features most intense anthropogenic globally; biological pump (BCP) contributes substantially. As Arctic sea-ice melts, BCP changes, impacting global other critical attributes (e.g. biodiversity). Full understanding requires year-round observations across a range...
Abstract Primary production in the Central Arctic Ocean (CAO) is limited by light and bioavailable nutrients. With decline of sea‐ice cover recent decades, resulting increase availability, nitrate limitation has been speculated to become more prominent. We used an eddy‐permitting biogeochemical model simulation estimate advective fluxes at different spatio‐temporal scales (synoptic, mesoscale sub‐mesoscale) over 1985–2015 period. found that pan‐Arctic continental slope contributes...
Abstract The 79 North Glacier (79NG) features Greenland’s largest floating ice tongue. Even though its extent has not changed significantly in recent years, observations have indicated a major thinning of the tongue from below. Both ocean warming and an increase subglacial discharge sheet induced by atmospheric could basal melt; however, available alone cannot tell which these is main driver. Here, we employ global simulation explicitly resolves circulation cavity with 700 m resolution to...
Abstract It is often unclear how to optimally choose horizontal resolution for the oceanic and atmospheric components of coupled climate models, which has implications their ability make best use available computational resources. Here we investigate effect using different combinations resolutions in atmosphere ocean on simulated a global model (Alfred Wegener Institute Climate Model [AWI‐CM]). Particular attention given Atlantic Meridional Overturning Circulation (AMOC). Four experiments...
Abstract. In the framework of developing a global modeling system which can facilitate studies on Arctic Ocean and high- to midlatitude linkage, we evaluate simulated by multi-resolution Finite Element Sea ice-Ocean Model (FESOM). To explore value using high horizontal resolution for modeling, use two meshes differing in only (24 km vs. 4.5 km). The significantly improves model's representation Ocean. most pronounced improvement is intermediate layer, terms both Atlantic Water (AW) mean...
Abstract Submesoscale flows are energetic motions on scales of several kilometers that may lead to substantial vertical motions. Here we present satellite and ship radar as well underway conductivity‐temperature‐depth Acoustic Doppler Current Profiler observations a cyclonic submesoscale filament in the marginal ice zone Fram Strait. The created 500‐m thin 50‐km long sea streak extends >250‐m depth with negative/positive density anomaly within/below halocline. frontal jets 0.5 m/s...
Abstract The Beaufort Gyre (BG) is the largest liquid freshwater reservoir of Arctic Ocean. content (FWC) significantly increased in BG 2000s during an anticyclonic wind regime and remained at a high level despite transition to more cyclonic state early 2010s. It not well understood what extent rapid sea ice decline this period has modified trend variability FWC past decade. Our numerical simulations show that about 50% accumulated can be explained by caused atmospheric warming. Among part...
Abstract The freshwater stored in the Arctic Ocean is an important component of global climate system. Currently liquid content (FWC) has reached a record high since beginning last century. In this study we use numerical simulations to investigate impact sea ice decline on FWC and its spatial distribution. unstructured-mesh ocean general circulation model Finite Element Sea Ice–Ocean Model (FESOM) with 4.5-km horizontal resolution region applied. show that increases by freshening through...
Abstract Simulating Arctic Ocean mesoscale eddies in ocean circulation models presents a great challenge because of their small size. This study employs an unstructured‐mesh ocean‐sea ice model to conduct decadal‐scale global simulation with 1‐km Arctic. It provides basinwide overview eddy energetics. Increasing resolution from 4 1 km increases kinetic energy (EKE) and total (TKE) by about 40% 15%, respectively. EKE is the highest along main currents over topography slopes, where strong...
Arctic Ocean sea ice cover is shrinking due to warming. Long-term sediment trap data shows higher export efficiency of particulate organic carbon in regions with seasonal compared without ice. To investigate this sea-ice enhanced export, we how different early summer phytoplankton communities seasonally ice-free and ice-covered the Fram Strait affect vertical dispersal microbes. In situ collected aggregates revealed two-fold diatom-rich regions, Phaeocystis region. Using microbial source...
The volume and freshwater transports through the Canadian Arctic Archipelago (CAA) are assessed using unstructured‐mesh Finite Element Sea ice‐Ocean Model (FESOM) in a global setup with CAA resolved at 5 km scale. hindcast simulation realistically represents fluxes main gates of Ocean sea ice conditions. During period 1968–2007, mean Lancaster Sound Nares Strait amount to 0.86 0.91 Sv, respectively. monthly transport western is highly correlated observational estimate (r = 0.81). seasonal...
Warm and salty Atlantic Water is transported by the Norwegian Current through Nordic Seas. A fraction of it enters Arctic Ocean where contributes significantly to its heat budget. Resolving complex circulation structure in Seas, particular eddies, presents a numerical challenge ocean models. Here, we present hindcast experiment for years 1969–2009 with global configuration Finite Element Sea-ice Model, employing high-resolution mesh Seas (4.5 km). We show that substantial improvements can be...
Abstract Ocean heat transport through the Barents Sea Opening (BSO) has strong impacts on ice extent and climate. In this paper we quantified contributions from different atmospheric forcing components to trend interannual variability of BSO transport. Ocean‐ice model simulations were conducted in which variation was maintained only or outside Arctic two simulations. The sum their anomalies reasonably replicated a hindcast simulation. upward mainly stems increasing ocean temperature subpolar...
Abstract Large amounts of atmospheric carbon can be exported and retained in the deep sea on millennial time scales, buffering global warming. However, while Barents Sea is one most biologically productive areas Arctic Ocean, retention times were thought to short. Here we present observations, complemented by numerical model simulations, that revealed a widespread lateral injection approximately 2.33 kt C d −1 from shelf some 1,200 m Nansen Basin, driven Bottom Water transport. With...
The mesoscale eddies have been studied in the open oceans for decades, identifying and tracking them satellites measuring their hydrographic properties from CTD profiles ships autonomous devices. However, this kind of study is more complex northernmost part world, where ocean's surface ice-covered all year round, leaving in-situ measurements as only way to eddies. In 2019, Multidisciplinary Drifting Observatory Study Arctic Climate (MOSAiC) expedition developed a distributed network devices...
Coupled ice sheet and ocean models are vital for projecting the dynamics of Antarctic Ice Sheet predicting future sea level rise. The Filchner-Ronne sector Antarctica contains a number deep-bedded streams glaciers potentially vulnerable to Marine Instability. Previous work has shown that, in warming climate, mode switch circulation could bring intrusions warm Circumpolar Deep Water (CDW) that would increase basal melt rates near deep grounding lines these glaciers. Furthermore, adjacent...
In the rapidly changing Arctic Ocean, marine primary productivity is tightly linked to balance between light and nutrient limitation. To capture this in ocean general circulation biogeochemical models (OGCBMs), a good representation of physics important due tight bio-physical coupling Arctic. Using horizontal model resolution few kilometers makes it possible resolve an increasing number small scale processes, that otherwise need be parameterized OGCBMs. Such high is, however, commonly not...
Abstract In this study, we investigate eddy dynamics in the northern Greenland Sea and Fram Strait using AVISO altimetry, spaceborne synthetic aperture radar (SAR), Finite Element ice‐Ocean Model (FESOM) high‐resolution numerical model data. region, eddies are thought to play an important role redistribution of warmer saltier Atlantic Water between Arctic Ocean areas deep convection central Sea. We found that detected SAR form two complementary data sets large mesoscale (with typical radii...
Abstract Atlantic Water (AW), which is transported northward by the West Spitsbergen Current (WSC), partly recirculates (i.e., turns westward) in Fram Strait. This determines how much heat and salt reaches Arctic Ocean, joins East Greenland on its southward path. We describe AW recirculation's location, seasonality, mesoscale variability analyzing first observations from moored instruments at five latitudes central Strait, spanning a period August 2016 to July 2018. observe recirculation...