Changing state of Arctic sea ice across all seasons

Environmental Research Letters, Journal Year: 2018, Volume and Issue: 13(10), P. 103001 - 103001

Published: Sept. 3, 2018

The decline in the floating sea ice cover Arctic is one of most striking manifestations climate change. In this review, we examine ongoing loss across all seasons. Our analysis based on satellite retrievals, atmospheric reanalysis, climate-model simulations and a literature review. We find that relative to 1981–2010 reference period, recent anomalies spring winter coverage have been more significant than any observed drop summer extent (SIE) throughout period. For example, SIE May November 2016 was almost four standard deviations below these months. Decadal during months has accelerated from −2.4 %/decade 1979 1999 −3.4%/decade 2000 onwards. also regional for given region, seasonal larger closer region outer edge cover. Finally, months, identify robust linear relationship between pan-Arctic total anthropogenic CO2 emissions. annual cycle per ton emissions ranges slightly above 1 m2 3 summer. Based extrapolation trends, Ocean will become sea-ice free August September an additional 800 ± 300 Gt emissions, while it becomes July October 1400

Language: Английский

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The Arctic Cloud Puzzle: Using ACLOUD/PASCAL Multiplatform Observations to Unravel the Role of Clouds and Aerosol Particles in Arctic Amplification

Bulletin of the American Meteorological Society, Journal Year: 2018, Volume and Issue: 100(5), P. 841 - 871

Published: Nov. 7, 2018

Abstract Clouds play an important role in Arctic amplification. This term represents the recently observed enhanced warming of relative to global increase near-surface air temperature. However, there are still knowledge gaps regarding interplay between clouds and aerosol particles, surface properties, as well turbulent radiative fluxes that inhibit accurate model simulations climate system. In attempt resolve this so-called cloud puzzle, two comprehensive closely coordinated field studies were conducted: Cloud Observations Using Airborne Measurements during Polar Day (ACLOUD) aircraft campaign Physical Feedbacks Boundary Layer, Sea Ice, Aerosol (PASCAL) ice breaker expedition. Both observational performed framework German Amplification: Climate Relevant Atmospheric Surface Processes, Feedback Mechanisms (AC)3 project. They took place vicinity Svalbard, Norway, May June 2017. ACLOUD PASCAL explored four pieces puzzle: impact on clouds, atmospheric radiation, dynamical processes. The instrumented 5 6 aircraft; icebreaker Research Vessel (R/V) Polarstern ; floe camp including tethered balloon; permanent ground-based measurement station at Ny-Ålesund, employed observe low- mid-level mixed-phase investigate related served a remote sensing observatory examining from above by downward-looking sensors; operated flying situ laboratory sampling inside below clouds. Most collocated 5/6 flights conducted either R/V or over Ny-Ålesund station, both which monitored using similar but upward-looking techniques aircraft. Several carried out underneath satellite tracks. paper motivates scientific objectives ACLOUD/PASCAL observations describes measured quantities, retrieved parameters, applied complementary instrumentation. Furthermore, it discusses selected results poses critical research questions be answered future papers analyzing data campaigns.

Language: Английский

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Understanding Arctic Ocean Circulation: A Review of Ocean Dynamics in a Changing Climate

Journal of Geophysical Research Oceans, Journal Year: 2020, Volume and Issue: 125(4)

Published: March 17, 2020

Abstract The Arctic Ocean is a focal point of climate change, with ocean warming, freshening, sea‐ice decline, and circulation that link to the changing atmospheric terrestrial environment. Major features interconnected nature its wind‐ buoyancy‐driven are reviewed here by presenting synthesis observational data interpreted from perspective geophysical fluid dynamics (GFD). general seen be superposition Atlantic Water flowing into around basin two main wind‐driven interior stratified Ocean: Transpolar Drift Stream Beaufort Gyre. specific drivers these systems, including wind forcing, ice‐ocean interactions, surface buoyancy fluxes, their associated GFD explored. essential understanding guides an assessment how structure might fundamentally change as warms, cover declines, ice remains becomes more mobile.

Language: Английский

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Physical manifestations and ecological implications of Arctic Atlantification

Nature Reviews Earth & Environment, Journal Year: 2021, Volume and Issue: 2(12), P. 874 - 889

Published: Nov. 16, 2021

Language: Английский

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Exceptional warming over the Barents area

Scientific Reports, Journal Year: 2022, Volume and Issue: 12(1)

Published: June 15, 2022

In recent decades, surface air temperature (SAT) data from Global reanalyses points to maximum warming over the northern Barents area. However, a scarcity of observations hampers confidence in this Arctic hotspot region. Here, we study past 20-40 years based on new available SAT and quality controlled comprehensive dataset archipelagos Sea. We identify statistically significant record-high annual up 2.7 °C per decade, with autumn 4.0 decade. Our results are compared most global regional reanalysis sets, as well remote sensing records sea ice concentration (SIC), (SST) high-resolution charts. The pattern is primarily consistent reductions cover confirms general spatial temporal patterns represented by reanalyses. our findings suggest even stronger rate SIC-SAT relation than was known region until now.

Language: Английский

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The Role of Atlantic Heat Transport in Future Arctic Winter Sea Ice Loss

Journal of Climate, Journal Year: 2019, Volume and Issue: 32(11), P. 3327 - 3341

Published: March 13, 2019

Abstract During recent decades Arctic sea ice variability and retreat during winter have largely been a result of variable ocean heat transport (OHT). Here we use the Community Earth System Model (CESM) large ensemble simulation to disentangle internally externally forced variability, assess what extent future trends are driven by Atlantic transport. We find that OHT into Barents Sea has been, is at present, major source internal predictability. In warming world (RCP8.5), remains good predictor although relation weakens as retreats beyond Sea. Warm water gradually spreads downstream from farther Ocean, leading reduced cover substantial changes in thickness. The long-term increase carried warmer current itself found weaken. weakening inflow contrast strengthening Nordic Seas circulation, thus not directly related slowdown meridional overturning circulation (AMOC). weakened rather results regional atmospheric acting change relative strength pathways Arctic. Internal associated with both upstream changes, including AMOC, large-scale anomalies reminiscent Oscillation.

Language: Английский

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Climate effects on temporal and spatial dynamics of phytoplankton and zooplankton in the Barents Sea

Progress In Oceanography, Journal Year: 2020, Volume and Issue: 185, P. 102320 - 102320

Published: April 8, 2020

Temporal and spatial dynamics of phytoplankton zooplankton in the Barents Sea have been investigated during last three decades using remote sensing situ observations. Satellite-derived sea surface temperatures increased period 1998–2017 by 1.0 °C as an average for Sea. We found significant positive relationships between ice-free conditions (open water area duration) satellite-based net primary production (NPP). The estimated annual NPP more than doubled over period, from around 40 to 100 Tg C. strong increase is result reduction ice, extending both available production. In areas where ice extent has decreased, satellite-derived chlorophyll a shows that timing peak spring bloom advanced month. Our results reveal ecosystem changing rapidly this change driven mainly bottom-up climatic processes. Autumn mesozooplankton biomass showed interannual variability 1990s, displaying inverse relationship with capelin biomass, most abundant planktivorous fish. some regions, e.g. Central Bank, explained up 50% 1989–2017. Though varied considerably, remained rather stable since mid-2000s (6–8 g dry wt. m−2), resulting weakening negative recent years. indicates favorable (prolonged/increased NPP) production, partly counteracting high predation levels. Overall, we observed trends phenology were strongly associated changes cover fluctuations temperature regime, trend may intensify should become even warmer due climate change. Further reductions algae expected adverse effects on sympagic fauna dependent species Arctic food web. promote further Atlantification (or borealization) plankton fish communities

Language: Английский

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Arctic Ocean Amplification in a warming climate in CMIP6 models

Science Advances, Journal Year: 2022, Volume and Issue: 8(30)

Published: July 27, 2022

Arctic near-surface air temperature warms much faster than the global average, a phenomenon known as Amplification. The change of underlying Ocean could influence climate through its interaction with sea ice, atmosphere, and ocean, but it is less well understood. Here, we show that upper 2000 m at 2.3 times mean rate within this depth range averaged over 21st century in Coupled Model Intercomparison Project Phase 6 Shared Socioeconomic Pathway 585 scenario. We call “Arctic Amplification.” amplified warming can be attributed to substantial increase poleward ocean heat transport, which will continue outweighing surface loss future. Amplification both atmosphere indicates whole one Earth’s regions most susceptible change.

Language: Английский

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Mechanisms and Impacts of Earth System Tipping Elements

Reviews of Geophysics, Journal Year: 2023, Volume and Issue: 61(1)

Published: Feb. 16, 2023

Abstract Tipping elements are components of the Earth system which may respond nonlinearly to anthropogenic climate change by transitioning toward substantially different long‐term states upon passing key thresholds or “tipping points.” In some cases, such changes could produce additional greenhouse gas emissions radiative forcing that compound global warming. Improved understanding tipping is important for predicting future risks and their impacts. Here we review mechanisms, predictions, impacts, knowledge gaps associated with 10 notable proposed be elements. We evaluate approaching critical whether shifts manifest rapidly over longer timescales. Some have a higher risk crossing points under middle‐of‐the‐road pathways will possibly affect major ecosystems, patterns, and/or carbon cycling within 21st century. However, literature assessing scenarios indicates strong potential reduce impacts many through mitigation. The studies synthesized in our suggest most do not possess abrupt years, exhibit behavior, rather responding more predictably directly magnitude forcing. Nevertheless, uncertainties remain elements, highlighting an acute need further research modeling better constrain risks.

Language: Английский

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Weakening of Cold Halocline Layer Exposes Sea Ice to Oceanic Heat in the Eastern Arctic Ocean

Journal of Climate, Journal Year: 2020, Volume and Issue: 33(18), P. 8107 - 8123

Published: Aug. 17, 2020

Abstract A 15-yr duration record of mooring observations from the eastern (>70°E) Eurasian Basin (EB) Arctic Ocean is used to show and quantify recently increased oceanic heat flux intermediate-depth (~150–900 m) warm Atlantic Water (AW) surface mixed layer sea ice. The upward release AW regulated by stability overlying halocline, which we has weakened substantially in recent years. Shoaling also contributed, with winter 2017–18 showing at only 80 m depth, just below wintertime layer, shallowest our records. weakening halocline for several months this time implies that was linked convection associated brine rejection during ice formation. This resulted a substantial increase season, an average 3–4 W −2 2007–08 >10 2016–18. seasonal loss EB equivalent more than twofold reduction growth. These changes imply positive feedback as reduced cover permits mixing, augmenting summer-dominated ice-albedo feedback.

Language: Английский

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