A central arctic extreme aerosol event triggered by a warm air-mass intrusion

Nature Communications, Год журнала: 2022, Номер 13(1)

Опубликована: Сен. 8, 2022

Abstract Frequency and intensity of warm moist air-mass intrusions into the Arctic have increased over past decades been related to sea ice melt. During our year-long expedition in remote central Ocean, a record-breaking increase temperature, moisture downwelling-longwave radiation was observed mid-April 2020, during an intrusion carrying air pollutants from northern Eurasia. The two-day intrusion, caused drastic changes aerosol size distribution, chemical composition particle hygroscopicity. Here we show how transformed low-particle environment area comparable central-European urban setting. Additionally, resulted explosive cloud condensation nuclei, which can direct effects on clouds’ radiation, their precipitation patterns, lifetime. Thus, unless prompt actions significantly reduce emissions source regions are taken, such events expected continue affect climate.

Язык: Английский

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Surface impacts and associated mechanisms of a moisture intrusion into the Arctic observed in mid-April 2020 during MOSAiC

Frontiers in Earth Science, Год журнала: 2023, Номер 11

Опубликована: Апрель 11, 2023

Distinct events of warm and moist air intrusions (WAIs) from mid-latitudes have pronounced impacts on the Arctic climate system. We present a detailed analysis record-breaking WAI observed during MOSAiC expedition in mid-April 2020. By combining Eulerian with Lagrangian frameworks using simulations across different scales, we investigate aspects mass transformations via cloud processes quantify related surface impacts. The is characterized by two distinct pathways, Siberian Atlantic. A static energy transport Circle above climatological 90th percentile found. Observations at research vessel Polarstern show transition radiatively clear to cloudy state significant precipitation positive balance (SEB), i.e., warming. parcels reach first near tropopause, only 1–2 days later lower altitudes. In 5 prior event, latent heat release formation triggers maximum diabatic heating rates excess 20 K d -1 . For some poleward drifting parcels, this facilitates strong ascent up 9 km. Based model experiments, explore role key cloud-determining factors. First, test moisture availability reducing lateral inflow 30%. This does not significantly affect liquid water path, therefore SEB, central Arctic. cause are counteracting mechanisms along trajectory. Second, impact increasing Cloud Condensation Nuclei concentrations 10 1,000 cm -3 (pristine highly polluted), which enhances content. Resulting stronger longwave cooling top makes entrainment more efficient deepens atmospheric boundary layer. Finally, strongly effect SEB. mainly driven turbulent fluxes over ocean, but radiation sea ice. also contributes large fraction Arctic, reaching 30% total 9-day period site. However, measured varies substantially between platforms. Therefore, estimates subject considerable observational uncertainty.

Язык: Английский

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Moisture origin, transport pathways, and driving processes of intense wintertime moisture transport into the Arctic

Weather and Climate Dynamics, Год журнала: 2022, Номер 3(1), С. 1 - 20

Опубликована: Янв. 6, 2022

Abstract. A substantial portion of the moisture transport into Arctic occurs in episodic, high-amplitude events with strong impacts on Arctic's climate system components such as sea ice. This study focuses origin moist-air intrusions during winter and examines sources, pathways, their linkage to driving large-scale circulation patterns. For that purpose, 597 intrusions, defined daily intense (exceeding 90th anomaly percentile) zonal mean polar cap (≥70∘ N), are identified. Kinematic backward trajectories combined a Lagrangian source diagnostic then used pinpoint sources characterize airstreams accomplishing transport. The analyses show bulk transported these originates eastern North Atlantic an uptake maximum poleward 50∘ N. Trajectories further reveal inverse relationship between latitude level at which is injected cap, consistent ascent poleward-flowing air baroclinic atmosphere. Focusing (424 intrusions), we find lower tropospheric predominantly accomplished by two types airstreams: (i) cold, warmed moistened surface fluxes (ii) subsiding from mid-troposphere boundary layer. Both contribute about 36 % each total former accounts for most associated anomalously high frequency cyclones east Greenland (218 whereas latter more important presence atmospheric blocking over Scandinavia Ural Mountains (145 events). Long-range transport, accounting 17 dominates weak forcing weather systems (64 intrusions). Finally, mid-tropospheric invariably (diabatically) ascending central western Atlantic, including Gulf Stream front, roughly 10 In summary, our shows atmosphere result combination high-latitude or high-altitude origin, whose relative importance determined underlying (i.e., blocks).

Язык: Английский

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Ecological impacts of climate change on Arctic marine megafauna

Trends in Ecology & Evolution, Год журнала: 2023, Номер 38(8), С. 773 - 783

Опубликована: Май 16, 2023

Global warming affects the Arctic more than any other region. Mass media constantly relay apocalyptic visions of climate change threatening wildlife, especially emblematic megafauna such as polar bears, whales, and seabirds. Yet, we are just beginning to understand ecological impacts on marine at scale Arctic. This knowledge is geographically taxonomically biased, with striking deficiencies in Russian strong focus exploited species cod. Beyond a synthesis scientific advances past 5 years, provide ten key questions be addressed by future work outline requested methodology. framework builds upon long-term monitoring inclusive local communities whilst capitalising high-tech big data approaches.

Язык: Английский

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Wavier jet streams driven by zonally asymmetric surface thermal forcing

Proceedings of the National Academy of Sciences, Год журнала: 2022, Номер 119(38)

Опубликована: Сен. 12, 2022

Recent studies have argued that global warming is responsible for a wavier jet stream, thereby driving midlatitude extreme flooding and drought. Polar amplification—the relative enhancement of high-latitude temperatures under warming—is to be the principal climate state extremes. Namely, decreased meridional temperature gradient suppresses mean zonal winds, leading jets. However, although observations are consistent with such linkage, detailed dynamical mechanism still debated. Here, we argue Northern Hemisphere land–sea thermal forcing contrast underlies zonally asymmetric drives response in planetary geostrophic motion, which provides balanced fields synoptic eddies midlatitudes thus streams. We show when barotropic wind U smaller than threshold, proportional β -plane effect dry static stability, flow field exhibits dramatic transition from confined near surface one reaching upper atmosphere. As enhances polar amplification, stream intensity suppressed. The confluence these effects leads

Язык: Английский

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The Critical Role of Euro‐Atlantic Blocking in Promoting Snowfall in Central Greenland

Journal of Geophysical Research Atmospheres, Год журнала: 2022, Номер 127(6)

Опубликована: Март 14, 2022

Abstract The Greenland Ice Sheet (GrIS) is losing mass at an increasing rate yet gain from snowfall still exceeds the loss attributed to surface melt processes on annual basis. This work assesses relationship between persistent atmospheric blocking across Euro‐Atlantic region and enhanced precipitation over central GrIS during June–August September–November. Results show that vast majority of events in coincide with blocking. During June–August, are produced primarily by mixed‐phase clouds (88%) linked a anticyclone southern (84%). slowly advects warm, moist air masses into western Greenland, positive temperature water vapor anomalies intensify GrIS. A zonal integrated transport pattern south indicates shift North Atlantic storm track associated high‐latitude In contrast, September–November largely ice‐phase (85%) Nordic Seas blocked flow northern Europe (78%). deflects westerly poleward enables rapid up steep southeastern edge GrIS, east southeast Greenland. These results emphasize critical role promoting importance accurate representation climate model projections.

Язык: Английский

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Amplified wintertime Barents Sea warming linked to intensified Barents oscillation

Environmental Research Letters, Год журнала: 2022, Номер 17(4), С. 044068 - 044068

Опубликована: Март 8, 2022

Abstract In recent decades, the Barents Sea has warmed more than twice as fast rest of Arctic in winter, but exact causes behind this amplified warming remain unclear. study, we quantify wintertime (BSW, for near-surface air temperature) with an average linear trend 1.74 °C decade −1 and interdecadal change around 2003 based on a surface energy budget analysis using ERA5 reanalysis dataset from 1979–2019. Our suggests that temperature is dominated by enhanced clear-sky downward longwave radiation (CDLW) associated increased total column water vapor. Furthermore, it found mode atmospheric variability over North Atlantic region known oscillation (BO) strongly contributed to BSW stepwise jump 2003. Since 2003, BO turned into strengthened positive phase, characteristic anomalous high pressure South Sea, which promoted two branches heat moisture transport southern Greenland along Norwegian Eurasian continent Sea. This vapor convergence resulting through CDLW. results highlight circulation related emerging driver meridional Ocean.

Язык: Английский

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Long-range transport and deposition on the Arctic snowpack of nuclear contaminated particulate matter

Journal of Hazardous Materials, Год журнала: 2023, Номер 452, С. 131317 - 131317

Опубликована: Март 28, 2023

The primary environmental concern related to nuclear power is the production of radioactive waste hazardous humans and environment. main scientific technological problems address this are storage disposal monitoring dispersion species into In work, we determined an anomalously high 14C activity, well above modern natural background, on surface seasonal snow sampled in early May 2019 glaciers Hornsund fjord area (Svalbard). Due lack local sources, concentrations suggest long-range atmospheric transport particles from lower latitudes, where plants treatment stations located. analysis synoptic meteorological data allowed us associate anomalous concentration intrusion event a warm humid air mass that likely brought pollutants Central Europe Arctic late April 2019. Elemental organic carbon, trace element data, scanning electron microscopy morphological were performed same samples better constrain process might have led radionuclide Svalbard. particular, highest values found snowpack (> 200 percent Modern Carbon, pMC) associated with lowest OC/EC ratios (< 4), indication anthropogenic industrial source, presence spherical rich iron, zirconium, titanium which, altogether, origin reprocessing plants. This study highlights role exposing environments human pollution. Given frequency intensity these warming events predicted increase due ongoing climate change, improving our knowledge their possible impact pollution becoming urgent.

Язык: Английский

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Dynamical linkages between Arctic Oscillations and winter precipitation patterns over the Indian Region

Global and Planetary Change, Год журнала: 2023, Номер 231, С. 104293 - 104293

Опубликована: Ноя. 8, 2023

Язык: Английский

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Sea ice concentration satellite retrievals influenced by surface changes due to warm air intrusions: A case study from the MOSAiC expedition

Elementa Science of the Anthropocene, Год журнала: 2023, Номер 11(1)

Опубликована: Янв. 1, 2023

Warm air intrusions over Arctic sea ice can change the snow and surface conditions rapidly alter concentration (SIC) estimates derived from satellite-based microwave radiometry without altering true SIC. Here we focus on two warm moist during Multidisciplinary drifting Observatory for Study of Climate (MOSAiC) expedition that reached research vessel Polarstern in mid-April 2020. After events, SIC deviations between different satellite products, including climate data records, were observed to increase. Especially, an underestimation algorithms based polarization difference was found. To examine causes this underestimation, used extensive MOSAiC measurements model computationally brightness temperatures a local scale. We further investigated by ground-based radiometers at frequencies 6.9 GHz, 19 89 GHz. show drop retrieved some products be attributed large-scale glazing, is, formation thin crust top snowpack, caused warming events. Another mechanism affecting which are mainly gradient ratios temperatures, is interplay changed temperature with metamorphism. From analyzed record found one less affected The low frequency channels GHz sensitive these changes, could exploited future obtain more accurate retrievals concentration. Strong expected become frequent thus their influence will In order provide consistent datasets, sensitivity needs addressed.

Язык: Английский

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