Carlos Moffat

University of Delaware researcher studying how warming temperatures in Antarctica could impact our region

WHYY  online

2023-02-18

Oceanographer Carlos Moffat and his graduate students returned to Delaware this month after spending 45 days at sea to better understand ocean warming and melting ice in the West Antarctic Peninsula — one of the fastest-warming regions in the world.

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Analysis | 50F in February? This Is What Climate Change Looks Like

The Washington Post  online

2023-02-15

At the poles, Arctic sea-ice extent was the third-lowest on record, according to the Copernicus Climate Change Service. Worse, Antarctic sea-ice coverage retreated to a record low, due to a stunning temperature surge in the Antarctic Ocean. “Even as somebody who’s been looking at these changing systems for a few decades, I was taken aback by what I saw, by the degree of warming that I saw” in the Antarctic, University of Delaware oceanographer Carlos Moffat told Inside Climate News.

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Enlighten Me: UD professor studies Antarctica’s melting ice

Delaware Public Media  online

2021-04-02

In this week’s Enlighten Me, Delaware Public Media’s Sophia Schmidt talks with coastal physical oceanographer and UD assistant professor Carlos Moffat about his plans for the five-year research and education grant he received from the National Science Foundation.

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At sea in Antarctica | UDaily

University of Delaware  online

2022-06-16

Cappola traveled to Antarctica to study physical oceanography with Carlos Moffat, assistant professor in the School of Marine Science and Policy. Cappola assisted Moffat in building three moorings that were later deployed by another ship, and he also assisted with water sampling operations, ocean profile analysis, and bathymetric sonar profiling. His work contributed to both the Phytoplankton and Optics group led by Oscar Schofield from Rutgers University and Jesse Turner from the University of Connecticut, as well as the Physical Oceanography group that Moffat leads at UD.

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Measuring melting ice | UDaily

University of Delaware  online

2021-02-03

As a coastal physical oceanographer, University of Delaware Assistant Professor Carlos Moffat has been interested in how coastal systems affect the larger climate and has worked on projects that measure the impact of the ocean on glacial ice retreat around the world for quite some time.

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Impact of shallow sills on heat transport and stratification regimes in proglacial fjords

2023 The increased melting and rapid retreat of glaciers is a main contributor to sea level rise. In shallow-silled fjords common in Patagonia, Alaska, and other systems, these bathymetric features may act as the first-order control on the dynamics, constraining fjord-shelf exchange and thereby modulating glacial melting. However, we still lack a clear understanding of how circulation and associated heat transport in shallow-silled glacial fjords are modulated by fjord-glacier geometry and fjord-shelf properties. To address this, idealized numerical simulations are conducted using a coupled plume-ocean fjord model.

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Long‐term patterns in ecosystem phenology near Palmer Station, Antarctica, from the perspective of the Adélie penguin

2023 Climate change is leading to phenological shifts across a wide range of species globally. Polar oceans are hotspots of rapid climate change where sea ice dynamics structure ecosystems and organismal life cycles are attuned to ice seasonality. To anticipate climate change impacts on populations and ecosystem services, it is critical to understand ecosystem phenology to determine species activity patterns, optimal environmental windows for processes like reproduction, and the ramifications of ecological mismatches. Since 1991, the Palmer Antarctica Long‐Term Ecological Research (LTER) program has monitored seasonal dynamics near Palmer Station. Here, we review the species that occupy this region as year‐round residents, seasonal breeders, or periodic visitors.

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Variability and Dynamics of Along‐Shore Exchange on the West Antarctic Peninsula (WAP) Continental Shelf

2022 The continental shelf of the West Antarctic Peninsula (WAP) is characterized by strong along‐shore hydrographic gradients resulting from the distinct influences of the warm Bellingshausen Sea to the south and the cold Weddell Sea water flooding Bransfield Strait to the north. These gradients modulate the spatial structure of glacier retreat and are correlated with other physical and biochemical variability along the shelf, but their structure and dynamics remain poorly understood. Here, the magnitude, spatial structure, seasonal‐to‐interannual variability, and driving mechanisms of along‐shore exchange are investigated using the output of a high‐resolution numerical model and with hydrographic data collected in Palmer Deep.

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A Recirculating Eddy Promotes Subsurface Particle Retention in an Antarctic Biological Hotspot

2021 Palmer Deep Canyon is one of the biological hotspots associated with deep bathymetric features along the West Antarctic Peninsula. The upwelling of nutrient‐rich Upper Circumpolar Deep Water to the surface mixed layer in the submarine canyon has been hypothesized to drive increased phytoplankton biomass, attracting krill, penguins and other top predators to the area. However, observations in Palmer Deep Canyon lack a clear in‐situ upwelling signal, laboratory experiments do not illustrate a physiological response by phytoplankton to Upper Circumpolar Deep Water, and surface residence times are too short for phytoplankton populations to reasonably respond to any locally upwelled nutrients. This suggests that local upwelling may not be the mechanism that links Palmer Deep Canyon to increased biological activity.

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Reframing Antarctica’s ice loss: impacts of cryospheric change on local human activity

2021 Physical scientists, social scientists, humanities scholars, and journalists have all framed Antarctica as a place of global importance—as a laboratory for scientific research, as a strategic site for geopolitical agendas, and more recently as a source of melting ice that could catastrophically inundate populations worldwide. Yet, the changing cryosphere impacts society within Antarctica as well, and this article expands the focus of Antarctic ice research to include human activities on and around the continent. It reframes Antarctica as a place with human history and local activities that are being affected by melting ice, even if the consequences are much smaller in scale than the effects of global sea level rise.

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Moffat, C., Meredith, M., 2018. Shelf–ocean exchange and hydrography west of the Antarctic Peninsula: a review

Moffat, C., Meredith, M.

2023-11-08

The West Antarctic Peninsula (WAP) is a highly productive marine ecosystem where extended periods of change have been observed in the form of glacier retreat, reduction of sea-ice cover and shifts in marine populations, among others. The physical environment on the shelf is known to be strongly influenced by the Antarctic Circumpolar Current flowing along the shelf slope and carrying warm, nutrient-rich water, by cold waters flooding into the northern Bransfield Strait from the Weddell Sea, by an extensive network of glaciers and ice shelves, and by strong seasonal to inter-annual variability in sea-ice formation and air–sea interactions, with significant modulation by climate modes like El Niño–Southern Oscillation and the Southern Annular Mode. However, significant gaps have remained in understanding the exchange processes between the open ocean and the shelf, the pathways and fate of oceanic water intrusions, the shelf heat and salt budgets, and the long-term evolution of the shelf properties and circulation. Here, we review how recent advances in long-term monitoring programmes, process studies and newly developed numerical models have helped bridge these gaps and set future research challenges for the WAP system.

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Wind-driven modulation of warm water supply to a proglacial fjord, Jorge Montt Glacier, Patagonia

Moffat, C.

2023-11-08

Projections of sea level rise due to ice loss from the land to the ocean have been hampered by a lack of understanding of the role the ocean is playing in glacier retreat, including the processes that contribute to the supply of warm water to the ice-ocean interface. Here shipboard, moored, and weather station data collected off Jorge Montt, a rapidly retreating glacier in Patagonia, are analyzed to understand the influence of wind forcing. During summer, synoptic-scale down-fjord wind events enhance an estuarine-like two-layer flow, increasing the inflow of oceanic deep water. During up-fjord wind events, the inflow of deep water is significantly reduced, and a three-layer exchange flow develops. Overall, along-fjord wind forcing is shown to modulate the inflow of warm water to the fjord by a factor of 2.5 The results suggest that local, channelized winds can be an important process modulating warm water supply and melting of tidewater glaciers.

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Variability and Dynamics of Along‐Shore Exchange on the West Antarctic Peninsula (WAP) Continental Shelf

Wang, X., Moffat, C., Dinniman, M.S., Klinck, J.M., Sutherland, D., Aguiar‐González, B.

2023-11-08

The continental shelf of the West Antarctic Peninsula (WAP) exhibits significant variations in water properties due to the influence of the warm Bellingshausen Sea in the south and the cold Weddell Sea water in the north, flowing through Bransfield Strait. These variations impact glacier retreat and other environmental factors, but their dynamics are not well understood. A study using a high-resolution numerical model and hydrographic data from Palmer Deep investigates the seasonal and interannual changes in along-shore transport. It reveals a seasonal pattern of water movement, with cold water moving towards the central WAP in winter and warmer water flowing towards Bransfield Strait in summer. The strength and direction of this flow are influenced by the Southern Annual Mode (SAM) and wind patterns, leading to variations in water temperature along the WAP continental shelf. This study underscores the importance of along-shore exchange in shaping the hydrographic conditions in the region.

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Variability and change in the west Antarctic Peninsula marine system: Research priorities and opportunities.

Henley, S.F., Schofield, O.M., Hendry, K.R., Schloss, I.R., Steinberg, D.K., Moffat, C., Peck, L.S., Costa, D.P., Bakker, D.C.E., Hughes, C., Rozema, P.D., Ducklow, H.W., Abele, D., Stefels, J., Van Leeuwe, M.A., Brussaard, C.P.D., Buma, A.G.J., Kohut, J., Sahade, R., Friedlaender, A.S., Stammerjohn, S.E., Venables, H.J., Meredith, M.P.

2023-11-08

The West Antarctic Peninsula (WAP) region has experienced significant temperature and sea ice dynamics changes since the mid-twentieth century, impacting the local ecosystem, ocean chemistry, and hydrographic conditions. Although changes in these trends have been observed in the 21st century, their effects on ocean physics, chemistry, and the high-productivity shelf ecosystem are not fully understood. The WAP shelf is crucial for krill stocks and higher trophic levels, making it a valuable model for studying how climate and sea ice variations may affect high-latitude ecosystems. Despite being one of the best-studied shelf regions in Antarctica, there are still gaps in spatial and temporal data needed to comprehend the complex system's dynamics and evolution. The summary outlines the current state of knowledge, identifies cross-disciplinary research priorities, and underscores the importance of defining the causes, extent, and timing of variability and change throughout the system. A coordinated observing system is necessary to monitor and understand these changes in the future.

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Global Drivers on Southern Ocean Ecosystems: Changing Physical Environments and Anthropogenic Pressures in an Earth System

Morley, S.A., Abele, D., Barnes, D.K.A., Cárdenas, C.A., Cotté, C., Gutt, J., Henley, S.F., Höfer, J., Hughes, K.A., Martin, S.M., Moffat, C., Raphael, M., Stammerjohn, S.E., Suckling, C.C., Tulloch, V.J.D., Waller, C.L., Constable, A.J.

2023-11-08

The manuscript examines the present and future global drivers of Southern Ocean (SO) ecosystems. Notably, atmospheric ozone depletion over Antarctica, beginning in the 1970s, has been a crucial factor, leading to stratospheric cooling and a stronger polar vortex, which in turn increases the occurrence of the Southern Annular Mode's positive phases (SAM). This results in warm air moving over the Western Antarctic Peninsula and cold air over the West Pacific sector. SAM and El Niño events also influence the Amundsen Sea Low, causing sea ice anomalies in the Pacific sectors. Strengthened westerly winds are associated with the upwelling of warmer water onto continental shelves, particularly in the East Pacific and Atlantic sectors. Melting glaciers and ice sheets have created ice-free areas that may enhance iron availability, potentially overcoming a limiting factor for primary production in much of the SO. Increasing CO2 is a significant anthropogenic driver with future effects on marine ecosystems, and the presence of persistent organic pollutants (POPs) and plastics is growing in the SO due to increased marine traffic and weaker ocean barriers. While the ongoing recovery of the ozone hole adds uncertainty to sea ice trends, the manuscript highlights the certain impacts of the current rate of change in physical and anthropogenic drivers on the Marine Ecosystem Assessment of the Southern Ocean (MEASO) in the near future, affecting a wide range of marine ecosystem aspects.

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