Tropical and Midlatitude Impact on Seasonal Polar Predictability in the Community Earth System Model

Abstract The impact on seasonal polar predictability from improved tropical and midlatitude forecasts is explored using a perfect-model experiment and applying a nudging approach in a GCM. We run three sets of 7-month long forecasts: a standard free-running forecast and two nudged forecasts in which atmospheric winds, temperature, and specific humidity (U, V, T, Q) are nudged toward one of the forecast runs from the free ensemble. The two nudged forecasts apply the nudging over different domains: the tropics (30°S–30°N) and the tropics and midlatitudes (55°S–55°N). We find that the tropics have modest impact on forecast skill in the Arctic or Antarctica both for sea ice and the atmosphere that is mainly confined to the North Pacific and Bellingshausen–Amundsen–Ross Seas, whereas the midlatitudes greatly improve Arctic winter and Antarctic year-round forecast skill. Arctic summer forecast skill from May initialization is not strongly improved in the nudged forecasts relative to the free forecast and is thus mostly a “local” problem. In the atmosphere, forecast skill improvement from midlatitude nudging tends to be largest in the polar stratospheres and decreases toward the surface.

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Polar Climate Instability and Climate Teleconnections from the Arctic to the Midlatitudes and Tropics

Journal of Climate ◽

10.1175/2009jcli2481.1 ◽

2009 ◽

Vol 22 (13) ◽

pp. 3513-3539 ◽

Cited By ~ 3

Author(s):

Guido Vettoretti ◽

Marc d’Orgeville ◽

William R. Peltier ◽

Marek Stastna

Keyword(s):

North Atlantic ◽

Meridional Overturning Circulation ◽

The Arctic ◽

Overturning Circulation ◽

Polar Climate ◽

Enso Events ◽

The North ◽

The North Atlantic ◽

The Tropics ◽

The Impact

Abstract It is generally accepted that the ocean thermohaline circulation plays a key role in polar climate stability and rapid climate change. Recently reported analyses of the impact of anomalous freshwater outflows from the North American continent onto either the North Atlantic or Arctic Oceans demonstrate that, in either case, a clear reduction in the Atlantic meridional overturning circulation, accompanied by an increase in sea ice extent, is predicted. The results also reconcile proxy-inferred Younger Dryas Greenland temperature variations. The aim of the present work is to provide a detailed investigation of the pathways along which the signal associated with overturning circulation anomalies propagates into both the midlatitudes and the tropics and the effect such teleconnections have on the tropical ocean–atmosphere system. The authors consider both the impact of substantial slowing of the overturning circulation due to freshwater forcing of the North Atlantic as well as its recovery after the anomalous forcing has ceased. The changes in tropical climate variability are shown to manifest themselves in shifts of both the typical time scale and intensity of ENSO events in the model. Evidence is presented for mechanisms that involve both atmospheric and oceanic pathways through which such Northern Hemisphere high-latitude events are communicated into both the midlatitudes and the tropics and thereafter transformed into changes in the nature of tropical variability.

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Healthcare System in the Arctic Zone of Russia. Known and Emerging Issues and Solutions to Them

Russian Economic Journal ◽

10.33983/0130-9757-2019-4-3-20 ◽

2019 ◽

pp. 3-20

Author(s):

V.N. Leksin

Keyword(s):

Metallurgical Industry ◽

Healthcare Services ◽

The Arctic ◽

Russian Arctic ◽

Arctic Zone ◽

Shift Workers ◽

The North ◽

Medical Institutions ◽

Emerging Issues ◽

The Impact

The impact on healthcare organization on the territory of Russian Arctic of unique natural and climatic, demographic, ethnic, settlement and professional factors of influencing the health of population, constantly or temporarily living on this territory is studied. The necessity is substantiated of various forms and resource provision with healthcare services such real and potential patients of Arctic medical institutions, as representatives of indigenous small peoples of the North, workers of mining and metallurgical industry, military personnel, sailors and shift workers. In this connection a correction of a number of All-Russian normative acts is proposed.

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Carbon cycle response to Dansgaard-Oeschger events in a freely oscillating LGM setup of the Community Earth System Model.

10.5194/egusphere-egu21-1556 ◽

2021 ◽

Author(s):

Markus Jochum ◽

Zanna Chase ◽

Roman Nutermn ◽

Joel Pedro ◽

Sune Rasmussen ◽

...

Keyword(s):

North Atlantic ◽

Deep Convection ◽

Time Lags ◽

Biological Productivity ◽

The North ◽

Community Earth System Model ◽

Free Running ◽

The North Atlantic ◽

Set Up ◽

The North Pacific

We use a LGM setup of the CESM with marine and terrestrial biogeochemistry. This free-running&#160; set-up (i.e., no freshwater hosing) exhibts Dansgaard-Oeschger events and Antarctic Isotope Maxima with time-lags and amplitudes that are consistent with paleo reconstructions. The CO2 signal associated DO events is also consistent with reconstructions: a 10 ppm/kyr increase during stadials, with the increase continuing some 400 years after Antarctica has started to cool again. An analysis of the modelled air-sea/land carbon fluxes reveals that some 3ppm of the stadial increase are due to shifting rain and temperature patterns that reduce growth of land vegetation. This adjustment is largely concluded after 3 centuries. The remainder of the signal is due to reduced ocean uptake. It turns out that reduced subduction of carbon in the Southern Ocean is mostly compensated by reduced upwelling in the equatorial oceans. Thus, as found in previous studies, much of the extra carbon is due to reduced uptake in the North Atlantic, partly directly due to reduced deep convection, and partly due to a reduced biological productivity because much of the North Atlantic nutrients are supplied by the AMOC. A big surprise is the emergence of the North Pacific as a major contributor to the changes in the air-fluxes of carbon. It is the reorganization of its wind-driven circulation that explains why global net-outgassing of carbon continues long after the interstadial has begun.

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The Coastal Observing System for Northern and Arctic Seas (COSYNA)

Ocean Science ◽

10.5194/os-13-379-2017 ◽

2017 ◽

Vol 13 (3) ◽

pp. 379-410 ◽

Cited By ~ 28

Author(s):

Burkard Baschek ◽

Friedhelm Schroeder ◽

Holger Brix ◽

Rolf Riethmüller ◽

Thomas H. Badewien ◽

...

Keyword(s):

Real Time ◽

The Arctic ◽

Arctic Seas ◽

The Public ◽

The North ◽

Data Products ◽

The North Sea ◽

Arctic Coast ◽

The Impact

Abstract. The Coastal Observing System for Northern and Arctic Seas (COSYNA) was established in order to better understand the complex interdisciplinary processes of northern seas and the Arctic coasts in a changing environment. Particular focus is given to the German Bight in the North Sea as a prime example of a heavily used coastal area, and Svalbard as an example of an Arctic coast that is under strong pressure due to global change.The COSYNA automated observing and modelling system is designed to monitor real-time conditions and provide short-term forecasts, data, and data products to help assess the impact of anthropogenically induced change. Observations are carried out by combining satellite and radar remote sensing with various in situ platforms. Novel sensors, instruments, and algorithms are developed to further improve the understanding of the interdisciplinary interactions between physics, biogeochemistry, and the ecology of coastal seas. New modelling and data assimilation techniques are used to integrate observations and models in a quasi-operational system providing descriptions and forecasts of key hydrographic variables. Data and data products are publicly available free of charge and in real time. They are used by multiple interest groups in science, agencies, politics, industry, and the public.

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Towards onset: shades of ENSO skill

10.5194/egusphere-egu2020-6358 ◽

2020 ◽

Author(s):

Dougal Squire ◽

James Risbey

Keyword(s):

El Niño ◽

Statistical Models ◽

El Nino ◽

Southern Oscillation ◽

Skill Score ◽

Forecast Skill ◽

The North ◽

Forecast Models ◽

The Impact ◽

Better Than

Climate forecast skill for the El Nino-Southern Oscillation (ENSO) is better than chance, but has increased little in recent decades. Further, the relative skill of dynamical and statistical models varies in skill assessments, depending on choices made about how to evaluate the forecasts. Using a suite of models from the North American Multi-Model Ensemble (NMME) archive we outline the consequences for skill of how the bias corrections and forecast anomalies are formed. We show that the method for computing forecast anomalies is such a critical part of the provenance of a skill score that any score for forecast anomalies lacking clarity about the method is open to wide interpretation. Many assessments of hindcast skill are likely to be overestimates of attainable forecast skill because the hindcast anomalies are informed by observations over the period assessed that would not be available to a real forecast. The relative skill rankings of forecast models can change between hindcast and forecast systems because the impact of model bias on skill is sensitive to the ways in which forecast anomalies are formed. Dynamical models are found to be more skillful than simple statistical models for forecasting the onset of El Nino events.

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Impact of SSM/I Observations Related to Moisture, Clouds, and Precipitation on Global NWP Forecast Skill

Monthly Weather Review ◽

10.1175/2007mwr2292.1 ◽

2008 ◽

Vol 136 (7) ◽

pp. 2713-2726 ◽

Cited By ~ 30

Author(s):

G. A. Kelly ◽

P. Bauer ◽

A. J. Geer ◽

P. Lopez ◽

J-N. Thépaut

Keyword(s):

Initial Conditions ◽

Forecast Skill ◽

Clear Sky ◽

Microwave Imager ◽

Set Up ◽

The Tropics ◽

The Impact ◽

Northern And Southern Hemispheres ◽

Experiment Duration

Abstract This paper presents the results from the Observing System Experiments (OSEs) with the current ECMWF data assimilation and modeling system for quantifying the impact on both analysis and forecast quality of Special Sensor Microwave Imager (SSM/I) observations sensitive to moisture and clouds as well as precipitation. SSM/I radiances have been assimilated operationally in clear-sky areas for 8 yr and in cloud- and rain-affected areas since June 2005. This paper examines experiments set up such that clear-sky and rain-affected observations were either added to a baseline with a restricted observing system configuration or withdrawn from the full system. The experiment duration was 10 weeks of which the first 14 days were excluded from the evaluation to allow the system to lose the memory of the initial conditions at day −1. It is shown that both clear-sky and rain-affected observations account for the bulk correction of moisture in the ECMWF analysis. SSM/I data adds 1 day of forecast skill over the first 48 h when evaluated in addition to a baseline-observing system. In the tropics, the rain-affected data contributes more skill to the moisture forecast than the clear-sky data at 700 hPa and above. In the Northern and Southern Hemispheres, the effect is generally weaker and slightly in favor of clear-sky observations. A similar performance can be seen with respect to the wind vector forecast skill, which reflects the connection between the analysis of moisture and dynamics.

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Assessment of safety and economy of navigation in ice on the Northen Sea route

AUTOBUSY – Technika Eksploatacja Systemy Transportowe ◽

10.24136/atest.2018.062 ◽

2018 ◽

Vol 19 (6) ◽

pp. 193-197 ◽

Cited By ~ 3

Author(s):

Tadeusz Pastusiak

Keyword(s):

Far East ◽

Route Planning ◽

The Arctic ◽

High Concentration ◽

Sea Transport ◽

The North ◽

Sea Transportation ◽

The North Sea ◽

Ice Conditions ◽

The Impact

This article discusses safety and economic issues of sea transport during transit voyages of a vessel across the North Sea Route (NSR) in the Arctic Ocean. The main obstacles to shipping and threat to vessels are the regions of ice occurrence and, in particular, clusters of ice with high and very high concentration, thickness and hummocking occurring each year in the same places, which are called ice massifs. Speed of vessels has the greatest impact on the economy of transit voyage. The safe speed of vessels, as a means of transport that ensures trouble-free navigation of the vessels depends on ice conditions. Until now, the concept of safe speed has not been precisely defined. Also, the impact of speed of the vessel in certain ice conditions on overcoming the ice and the risk of damage to vessel has not been precisely defined. Issues of direct and potential costs of vessel’s safety, damages and consequences of damages in ice were also not fully considered. The author analyzed the above relationships on the example of the first commercial vessel transit voyage through the NSR and obtained generalized results that can be applied to the initial, general and tactical route planning till 10 days - 6 months ahead and transit schedule of a vessel between Europe and the Far East ports via the Northern Sea Route. The presented method should increase safety and economy of sea transportation in areas covered with ice.

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Transport and Fate of 137Cs Released From Multiple Sources in the North Atlantic and Arctic Oceans

Frontiers in Marine Science ◽

10.3389/fmars.2021.806450 ◽

2021 ◽

Vol 8 ◽

Author(s):

Vladimir Maderich ◽

Kyeong Ok Kim ◽

Roman Bezhenar ◽

Kyung Tae Jung ◽

Vazira Martazinova ◽

...

Keyword(s):

Bottom Sediment ◽

North Atlantic ◽

River Runoff ◽

Global Fallout ◽

The Arctic ◽

Multiple Sources ◽

The North ◽

The North Atlantic ◽

The Impact ◽

Secondary Contamination

The North Atlantic and Arctic oceans, along with the North Pacific, are the main reservoirs of anthropogenic radionuclides introduced in the past 75 years. The POSEIDON-R compartment model was applied to the North Atlantic and Arctic oceans to reconstruct 137Cs contamination in 1945–2020 due to multiple sources: global fallout, exchange flows with other oceans, point-source inputs in the ocean from reprocessing plants and other nuclear facilities, the impact of the Chernobyl accident and secondary contamination resulting from river runoff and redissolution from bottom sediments. The model simulated the marine environment as a system of 3D compartments comprising the water column, bottom sediment, and biota. The dynamic model described the transfer of 137Cs through the pelagic and benthic food chains. The simulation results were validated using the marine database MARIS. The calculated concentrations of 137Cs in the seaweed and non-piscivorous and piscivorous pelagic fish mostly followed the concentration of 137Cs in water. The concentration in coastal predator fish lagged behind the concentration in water as a result of a diet that includes both pelagic and benthic organisms. The impact of each considered source on the total concentration of 137Cs in non-piscivorous fish in the regions of interest was analyzed. Whereas the contribution from global fallout dominated in 1960–1970, in 1970–1990, the contribution of 137Cs released from reprocessing plants exceeded the contributions from other sources in almost all considered regions. Secondary contamination due to river runoff was less than 4% of ocean influx. The maximum total inventory of 137Cs in the Arctic Ocean (31,122 TBq) was reached in 1988, whereas the corresponding inventory in the bottom sediment was approximately 6% of the total. The general agreement between simulated and observed 137Cs concentrations in water and bottom sediment was confirmed by the estimates of geometric mean and geometric standard deviation, which varied from 0.89 to 1.29 and from 1.22 to 1.87, respectively. The approach used is useful to synthesize measurement and simulation data in areas with observational gaps. For this purpose, 13 representative regions in the North Atlantic and Arctic oceans were selected for monitoring by using the “etalon” method for classification.

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Gender-specific perceptions of environmental problems by the indigenous peoples of the North of Russia

POPULATION ◽

10.19181/population.2020.23.2.7 ◽

2020 ◽

Vol 23 (2) ◽

pp. 72-84

Author(s):

Evgenia V. Potravnaya

Keyword(s):

Indigenous Peoples ◽

Industrial Development ◽

Local Population ◽

Environmental Problems ◽

The Arctic ◽

Full Account ◽

Mining Companies ◽

The North ◽

The Impact ◽

Gender Specific

The article deals with gender aspects of the perception of environmental problems by the population in the industrial development of the Arctic. There is substantiated the need to develop an ethno-social approach to the study of environmental problems in the framework of interaction between mining companies and the indigenous peoples of the North. It is proposed to conduct sociological surveys of the population when assessing the impact on the ethnological environment (ethnological expertise of the project). The experience of conducting such research to identify and assess gender-specific perceptions of environmental problems in the implementation of investment projects in the Arctic is shown. Based on the results of the empirical research in 2017–2019 on alluvial gold and diamond mining projects in the Northern regions of the Republic of Sakha (Yakutia), the main environmental problems that concern the local population are identified. These include: pollution of the environment in the territories of traditional nature use, decrease in the number of deer, reduction in the number of objects of traditional crafts, lack of a system for garbage removal and processing, climate change, and others. The article shows specifics of the environmental problems perception by the indigenous inhabitants of the North (Evenks, Dolgans, Yukagirs, Sakha) on a gender basis. It proposes a mechanism for taking into account the gender characteristics of the population’s behavior in the impact of economic activities on the environment in order to ensure gender equality by signing an agreement between mining companies and the local population on the socio-economic development of the territory. The concept of a gender approach to the account of ethnosocial and environmental aspects of territory development with the account the life cycle of the project is substantiated. Implementation of this approach will allow a more full account of the interests and needs of the indigenous population in the industrial development of the territory in the Arctic.

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Sea ice kinematic features in the Arctic outflow region and their associations with Arctic Northeast Passage accessibility

Abstracts of the ICA ◽

10.5194/ica-abs-1-101-2019 ◽

2019 ◽

Vol 1 ◽

pp. 1-1

Author(s):

Dawei Gui ◽

Xiaoping Pang ◽

Ruibo Lei ◽

Xi Zhao ◽

Jia Wang

Keyword(s):

Sea Ice ◽

Arctic Sea Ice ◽

The Arctic ◽

Fram Strait ◽

The North ◽

Atmospheric Circulation Indices ◽

Arctic Sea ◽

Outflow Region ◽

Transpolar Drift ◽

The Impact

Abstract. Increasing amounts of evidence have proven Arctic sea ice is undergoing remarkable loss. On the bright side, the Arctic sea routes are becoming increasingly accessible. In this study, the NSIDC product of sea ice motion was applied to reconstruct the northward speed of sea ice to obtain the kinematic features of the sea ice in the Arctic outflow region which specially referred to the Fram Strait and to the north of the Northeast Passage (NEP).In the Arctic outflow region, the average southward displacement of sea ice in 2007&ndash;2014 (1511&thinsp;km) was more than twice the average prior to 2007 (617&thinsp;km), which indicated continuous enhancement of the Transpolar Drift Stream (TDS) in comparison with previous years. In the regions to the north of the NEP, the long-term trend of northward sea ice speed in the Kara sector was +0.04&thinsp;cm&thinsp;s&minus;1&thinsp;year&minus;1 in spring. A significant statistical relationship was found between the NEP open period and the northward speed of the sea ice to the north of the NEP. The offshore advection of sea ice could account for the opening of sea routes by 33% and 15% in the Kara and Laptev sectors, respectively.The atmospheric circulation indices across the TDS, i.e., the Central Arctic Index (CAI), presented more significant correlation than for the Arctic atmospheric Dipole Anomaly index with the open period of the NEP, and the CAI could explain the southward displacement of sea ice toward Fram Strait by more than 45%. The impact from the summer positive CAI reinforces the thinning and mechanical weakening of the sea ice in the NEP region, which promoted the navigability of the NEP.

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