The MOSAiC Distributed Network: Observing the coupled Arctic system with multidisciplinary, coordinated platforms

Elementa Science of the Anthropocene, Год журнала: 2024, Номер 12(1)

Опубликована: Янв. 1, 2024

Central Arctic properties and processes are important to the regional global coupled climate system. The Multidisciplinary drifting Observatory for Study of Climate (MOSAiC) Distributed Network (DN) autonomous ice-tethered systems aimed bridge gaps in our understanding temporal spatial scales, particular with respect resolution Earth system models. By characterizing variability around local measurements made at a Observatory, DN covers both interactions involving ocean-ice-atmosphere interfaces as well three-dimensional ocean, sea ice, atmosphere. more than 200 instruments (“buoys”) were varying complexity set up different sites mostly within 50 km Observatory. During an exemplary midwinter month, observations captured atmospheric on sub-monthly time but less so monthly means. They show significant snow depth ice thickness, provide temporally spatially resolved characterization motion deformation, showing coherency scale smaller scales. Ocean data background gradient across dependent due mixed layer sub-mesoscale mesoscale processes, influenced by variable cover. second case (May–June 2020) illustrates utility during absence manually obtained providing continuity physical biological this key transitional period. We examples synergies between extensive MOSAiC remote sensing numerical modeling, such estimating skill drift forecasts evaluating modeling. has been proven enable analysis atmosphere-ice-ocean potential improve model parameterizations important, unresolved future.

Язык: Английский

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Cloud radiative effect dominates variabilities of surface energy budget in the dark Arctic

Scientific Reports, Год журнала: 2025, Номер 15(1)

Опубликована: Янв. 23, 2025

Climate models simulate a wide range of temperatures in the Arctic. Here we investigate one main drivers changes surface temperature: net heat flux models. We show that winter months dark Arctic, there is more than two-fold difference fluxes among models, and this dominated by downward infrared radiation from clouds. Owing to small amount water vapor clouds transmits easily Arctic at other latitudes, resulting large cloud radiative effect surface. The dominant role also found transient variability flux. Results demonstrate accurate simulation crucial for determining flux, which turn affects temperature sea ice properties

Язык: Английский

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Comparison of selected surface level ERA5 variables against in‐situ observations in the continental Arctic

Quarterly Journal of the Royal Meteorological Society, Год журнала: 2024, Номер 150(761), С. 2123 - 2146

Опубликована: Апрель 1, 2024

Abstract In this study, data from 17 ground‐based, continental Arctic observatories are used to evaluate the performance of European Centre for Medium‐Range Weather Forecasts Reanalysis version 5 (ERA5) reanalysis model. Three aspects evaluated: (i) overall reproducibility variables at all stations seasons one‐hour time resolution; (ii) seasonal performance; and (iii) between different temporal resolutions (one hour one month). Performance is evaluated based on slope, R 2 value, root‐mean‐squared error (RMSE). We focus surface meteorological including 2‐m air temperature (temperature), relative humidity (RH), pressure, wind speed, zonal meridional speed components, short‐wave downward (SWD) radiation flux. The comparison revealed best results pressure (0.98 ± 0.02, mean standard deviation [ σ ]), followed by (0.94 0.02), SWD flux (0.87 0.03) while (0.49 0.12), RH (0.42 0.20), (0.163 0.15) (0.129 0.17) displayed poor results. also found that certain (surface meridional, speed) showed no dependency others (temperature, RH, flux) performed better during seasons. Improved were observed when decreasing resolution month temperature, However, (RH pressure) comparatively worse monthly resolution. Overall, ERA5 performs well in Arctic, but caution needs be taken with which has implications use global climate models. Our useful scientific community as it assesses confidence placed each produced ERA5.

Язык: Английский

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Surface Energy Balance Responses to Radiative Forcing in the Central Arctic From MOSAiC and Models

Journal of Geophysical Research Atmospheres, Год журнала: 2025, Номер 130(6)

Опубликована: Март 10, 2025

Abstract The Arctic surface energy budget (SEB) couples the atmosphere with sea ice, making it useful for both studying processes as well evaluating models. Improved understanding of atmosphere‐ice interactions is required to improve models, requiring year‐round observations address seasonally dependent biases. This work uses novel from MOSAiC expedition quantify responses fluxes radiative forcing over ice throughout a complete annual cycle. We identify two primary regimes flux response: an growth regime in winter and melt summer. In regime, changes impact upwelling longwave, sensible heat, subsurface heat fluxes, whereas primarily alter amount transmission because temperature fixed. These observed are used evaluate seven weather forecast models during regime. most do not match observations. Many also have biased downwelling longwave. One model (the Coupled Forecast System; CAFS) adequately captures mean winter. CAFS further evaluated against spanning full year, demonstrating sufficient agreement provide more generalized these SEB process relationships across Arctic.

Язык: Английский

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Overview: Quasi-Lagrangian observations of Arctic air mass transformations – Introduction and initial results of the HALO–(AC)³ aircraft campaign

Опубликована: Март 26, 2024

Abstract. The global warming is amplified in the Arctic. To collect data that help to constrain weather and climate models, which often do not realistically represent enhanced Arctic warming, HALO-(AC)³ aircraft campaign was conducted March April 2022 over Norwegian Greenland Seas, Fram Strait, central Ocean. Observations were made areas of open ocean, marginal sea ice zone, ice. Two low-flying one long-range, high-altitude research have been employed. Whenever possible, three flown collocated formation. focused on specific challenge posed by models: reasonable representation transformations air masses during their meridional transport into (northward moist warm intrusions, WAIs) out (southward via marine cold outbreaks, CAOs) observe mass transformations, a quasi-Lagrangian flight strategy using trajectory calculations realized enabling sample moving parcels twice along trajectories. Eight distinct WAI 12 CAO cases probed extensively. From measurements, we derived diabatic heating moistening CAOs WAIs, development cloud macrophysical microphysical properties southward pathways CAOs, moisture budget WAIs. As an example result, obtained typical values surface-driven between 1–3 K h-1 near-surface 0.05–0.3 g kg-1 within lowest about 0.5 km. observations weak cooling up 0.4 loss 0.1 from ground 5 km altitude derived. In addition, discuss frequency occurrence different thermodynamic phases low-level clouds, interaction cirrus with ice, water vapor, aerosol particles, characteristic chemical particles. Finally, provide proof concept measure mesoscale divergence subsidence dropsondes released circular patterns.

Язык: Английский

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Sea ice cover in the Copernicus Arctic Regional Reanalysis

˜The œcryosphere, Год журнала: 2024, Номер 18(3), С. 1157 - 1183

Опубликована: Март 12, 2024

Abstract. The Copernicus Arctic Regional Reanalysis (CARRA) is a novel regional high-resolution atmospheric reanalysis product that covers considerable part of the European including substantial amounts ice-covered areas. Sea ice in CARRA modelled by means one-dimensional thermodynamic sea parameterisation scheme, which also explicitly resolves evolution snow layer over ice. In present study, we assess representation cover and validate it against wide set satellite products observations from mass balance buoys. We show adequately represents general interannual trends towards thinner warmer Arctic. Compared to ERA5, shows reduced warm bias surface temperature. strongest improvement was observed for winter months central Greenland Barents seas where 4.91 °C median temperature error ERA5 1.88 on average. Over Baffin Bay, intercomparisons suggest presence cold winter-time CARRA. No found albedo with spring-time errors being up 0.08 higher average than those when computed CLARA-A2 retrieval product. Summer-time albedos are comparable ERA5. thickness depth resolve annual cycle bring added value compared However, limitations indicate potential benefits utilising more advanced approaches representing next-generation reanalyses.

Язык: Английский

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Characterisation of low-base and mid-base clouds and their thermodynamic phase over the Southern Ocean and Arctic marine regions

Atmospheric chemistry and physics, Год журнала: 2024, Номер 24(12), С. 7359 - 7383

Опубликована: Июнь 27, 2024

Abstract. The thermodynamic phase of clouds in low and middle levels over the Southern Ocean Arctic marine regions is poorly known, leading to uncertainties radiation budget weather climate models. To improve knowledge cloud phase, we analyse 2 years raDAR-liDAR (DARDAR) dataset based on active satellite instruments. We classify according their base top height focus low-, mid-, mid- low-level as they are most frequent mixed-phase temperature regime. Low-level single-layer occur 8 %–15 % all profiles, but spanning mid-level also amount approx. 15 %. Liquid show mainly a smaller vertical extent horizontally larger compared ice clouds. results highest liquid fractions for Two local minima fraction observed around temperatures −15 −5 °C. Mid-level both polar higher if sea open ocean. with high salt concentrations, used proxy spray, reduced fractions. In clouds, dust shows largest correlations fraction, lower aerosol concentration. clearly contribution shortwave radiative effect regions, followed by

Язык: Английский

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The Year of Polar Prediction site Model Intercomparison Project (YOPPsiteMIP) phase 1: project overview and Arctic winter forecast evaluation

Geoscientific model development, Год журнала: 2024, Номер 17(14), С. 5511 - 5543

Опубликована: Июль 24, 2024

Abstract. Although the quality of weather forecasts in polar regions is improving, forecast skill there still lags behind lower latitudes. So far have been relatively few efforts to evaluate processes numerical prediction systems using situ and remote sensing datasets from meteorological observatories terrestrial Arctic Antarctic compared mid-latitudes. Progress has limited both by heterogeneous nature observatory data availability parameters needed perform process-oriented evaluation multi-model archives. The Year Polar Prediction (YOPP) site Model Inter-comparison Project (YOPPsiteMIP) addressing this gap producing merged files (MODFs) model (MMDFs), bringing together observations at a format designed facilitate evaluation. An performance was performed seven sites, focussing on first YOPP Special Observing Period Northern Hemisphere (NH-SOP1) February March 2018. It demonstrated that although characteristics vary between different sites systems, an underestimation boundary layer temperature variability across models, which goes hand with inability capture cold extremes, common issue several sites. found many models tend underestimate sensitivity 2 m air (T2m) surface skin variations radiative forcing, reasons for are discussed.

Язык: Английский

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A comprehensive in situ and remote sensing data set collected during the HALO–(𝒜 𝒞)³ aircraft campaign

Earth system science data, Год журнала: 2025, Номер 17(3), С. 1295 - 1328

Опубликована: Апрель 1, 2025

Abstract. The HALO–(𝒜𝒞)3 aircraft campaign was carried out in March and April 2022 over the Norwegian Greenland seas, Fram Strait, central Arctic Ocean. Three research – High Altitude Long Range Research Aircraft (HALO), Polar 5, 6 performed 54 partly coordinated flights on 23 flight days areas of open ocean, marginal sea ice zone (MIZ), ice. general objective to quantify evolution air mass properties during moist warm-air intrusions (WAIs) cold-air outbreaks (CAOs). To obtain a comprehensive data set, three operated following different strategies. HALO equipped with active passive remote sensing instruments dropsondes cover regional cloud thermodynamic processes. 5 similar payload HALO, instrumented situ cloud, aerosol, trace gas focusing initial transformation close MIZ. processed, calibrated, validated are published World Data Center PANGAEA as instrument-separated subsets listed aircraft-separated collections for (Ehrlich et al., 2024a, https://doi.org/10.1594/PANGAEA.968885), (Mech https://doi.org/10.1594/PANGAEA.968883), (Herber 2024, https://doi.org/10.1594/PANGAEA.968884). A detailed overview available sets is provided here. Furthermore, campaign-specific instrument setup, processing, quality summarized. Based measurements conducted specific CAO, it shown that scientific analysis benefits from operation aircraft.

Язык: Английский

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Characteristics and effects of aerosols during blowing snow events in the central Arctic

Elementa Science of the Anthropocene, Год журнала: 2025, Номер 13(1)

Опубликована: Янв. 1, 2025

Sea salt aerosol (SSaer) significantly impacts aerosol-radiation and aerosol-cloud interactions, sublimated blowing snow is hypothesized to be an important SSaer source in polar regions. Understanding other wind-sourced aerosols’ climate relevant properties needed, especially during winter when Arctic amplification greatest. However, most of our understanding comes from modeling studies, direct observations are sparse. Additionally, can originate multiple sources, making it difficult disentangle emission processes. Here, we present comprehensive events the Multidisciplinary drifting Observatory for Study Climate (MOSAiC) expedition central Arctic. High wind speed strongly enhances total number, submicron sodium chloride mass, cloud condensation nuclei concentrations, scattering coefficients. Generally, relative response enhancement strongest fall concentrations lowest. Blowing showed similar environmental across events, apart occasions with high age (>6 days since last snowfall). Coarse-mode number (>1 μm) better explained by variability averaged over 12-h air mass back trajectories arriving at MOSAiC site compared local, instantaneous speed, suggesting importance regional transport consideration history wind-driven production. These provide new insights into may help validate studies improve model parameterizations particularly indirect radiative forcing.

Язык: Английский

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