scholarly journals Variability of the mixed phase in the Arctic with a focus on the Svalbard region: a study based on spaceborne active remote sensing

2014 ◽  
Vol 14 (16) ◽  
pp. 23453-23497
Author(s):  
G. Mioche ◽  
O. Jourdan ◽  
M. Ceccaldi ◽  
J. Delanoë
Keyword(s):  
Climate Change ◽  
Remote Sensing ◽  
Arctic Region ◽  
Supercooled Liquid ◽  
Mixed Phase ◽  
The Arctic ◽  
Retrieval Algorithm ◽  
Temporal And Spatial Distribution ◽  
Svalbard Archipelago ◽  
The Arctic Region

Abstract. The Arctic region is known to be very sensitive to climate change. Clouds and in particular mixed phase clouds (MPC) remain one of the greatest sources of uncertainties in the modeling of the Arctic response to climate change due to an inaccurate representation of their variability and their quantification. In this study, we present a characterization of the vertical, spatial and seasonal variability of Arctic clouds and MPC over the whole Arctic region based on satellite active remote sensing observations. MPC properties in the region of Svalbard archipelago (78° N, 15° E) are also investigated. The occurrence frequency of clouds and MPC are determined from CALIPSO/CLOUDSAT measurements processed with the DARDAR retrieval algorithm which allows for a reliable cloud thermodynamic phase classification (warm liquid, supercooled liquid, ice, mixing of ice and supercooled liquid). Significant differences are observed between MPC variability over the whole Arctic region and over the Svalbard region. Results show that MPC are ubiquitous all along the year, with a minimum occurrence of 30% in winter and 50% during the rest of the year, in average over the whole Arctic. Over the Svalbard region, MPC occurrence is more constant with time with larger values (55%) compared to the average observed in the Arctic. MPC are especially located at low altitudes, below 3000 m, where their frequency of occurrence reaches 90%, in particular during winter, spring and autumn. Moreover, results highlight that MPC statistically prevail over sea. The temporal and spatial distribution of MPC over the Svalbard region seems to be linked to the contribution of moister air and warmer water from the North Atlantic Ocean which contribute to the initiation of the liquid water phase. Over the whole Arctic, and particularly in western regions, the increase of MPC occurrence from spring to autumn could be connected to the sea ice melting. During this period, the open water transports a part of the warm water from the Svalbard region to the rest of the Arctic region. This facilitates the vertical transfer of moisture and thus the persistence of the liquid phase. A particular attention is also paid on the measurements uncertainties and how they could affect our results.

scholarly journals Variability of mixed-phase clouds in the Arctic with a focus on the Svalbard region: a study based on spaceborne active remote sensing

2015 ◽  
Vol 15 (5) ◽  
pp. 2445-2461 ◽  
Author(s):  
G. Mioche ◽  
O. Jourdan ◽  
M. Ceccaldi ◽  
J. Delanoë
Keyword(s):  
Climate Change ◽  
North Atlantic ◽  
North Atlantic Ocean ◽  
Arctic Region ◽  
Supercooled Liquid ◽  
The Arctic ◽  
The North ◽  
The North Atlantic ◽  
Mixed Phase Clouds ◽  
The Arctic Region

Abstract. The Arctic region is known to be very sensitive to climate change. Clouds and in particular mixed-phase clouds (MPCs) remain one of the greatest sources of uncertainties in the modelling of the Arctic response to climate change due to an inaccurate representation of their variability and their quantification. In this study, we present a characterisation of the vertical, spatial and seasonal variability of Arctic clouds and MPCs over the entire Arctic region based on satellite active remote sensing observations. MPC properties in the region of the Svalbard archipelago (78° N, 15° E) are also investigated. The occurrence frequency of clouds and MPCs are determined from CALIPSO/CLOUDSAT measurements processed with the DARDAR retrieval algorithm, which allow for a reliable cloud thermodynamic phase classification (warm liquid, supercooled liquid, ice, mixing of ice and supercooled liquid). Significant differences are observed between MPC properties over the entire Arctic region and over the Svalbard region. Results show that MPCs are encountered all year long, with a minimum occurrence of 30% in winter and 50% during the rest of the year on average over the entire Arctic. Over the Svalbard region, MPC occurrence is more constant with time with larger values (55%) compared to the average observed in the Arctic. MPCs are especially located at low altitudes, below 3000 m, where their frequency of occurrence reaches 90%, particularly during winter, spring and autumn. Moreover, results highlight that MPCs are statistically more frequent above open sea than land or sea ice. The temporal and spatial distribution of MPCs over the Svalbard region seems to be linked to the supply of moister air and warmer water from the North Atlantic Ocean, which contribute to the initiation of the liquid water phase. Over the whole Arctic, and particularly in western regions, the increase of MPC occurrence from spring to autumn could be connected to the sea ice melting. During this period, the open water transports some of the warm water from the North Atlantic Ocean to the rest of the Arctic region. This facilitates the vertical transfer of moisture and thus the persistence of the liquid phase. Particular attention is also paid to the measurement uncertainties and how they could affect our conclusions.

Áhrif loftlagsbreytinga á vatnsveitur og vatnsgæði á Íslandi – áhættuþættir og aðgerðir

2019 ◽  
Vol 25 ◽  
pp. 5-19
Author(s):  
María J. Gunnarsdóttir ◽  
Sigurður Magnús Garðarsson ◽  
Hrund Ólöf Andradóttir ◽  
Alfreð Schiöth
Keyword(s):  
Climate Change ◽  
Risk Factors ◽  
Water Quality ◽  
Risk Assessment ◽  
Drinking Water ◽  
Arctic Region ◽  
The Arctic ◽  
Related Factors ◽  
Surveillance Area ◽  
The Arctic Region

Climate change is expected to have impact on water supply and drinking water quality in Iceland. Foremost there are three influential weather-related factors; increase in temperature; rise in sea level; and seasonal and regional change in precipitation in both quantity and intensity. In this study international and local reports and articles were analyzed for expected impact on the water resource with emphasis on the northern and the arctic region. Water quality risk factors were analyzed based on surveillance data of the water supplies from the Local Competent Authorities. Preliminary risk assessment of landslides and flooding was performed in one surveillance area in northern Iceland.

Visualizing climate change in the Arctic and beyond: Participatory media and the United Nations Conference of the Parties (COP), and interactive Indigenous Arctic media

2020 ◽  
Vol 1 (1) ◽  
pp. 79-99 ◽  
Author(s):  
Scott MacKenzie ◽  
Anna Westerstahl Stenport
Keyword(s):  
Climate Change ◽  
United Nations ◽  
Climate Science ◽  
Arctic Region ◽  
The Arctic ◽  
Moving Images ◽  
Big Data Visualization ◽  
The United Nations ◽  
Vexing Problem ◽  
The Arctic Region

Impactful communication remains a vexing problem for climate science researchers and public outreach. This article identifies a range of moving images and screen-based media used to visualize climate change, focusing especially on the Arctic region and the efforts of the United Nations. The authors examine the aesthetics of big data visualization of melting sea ice and glaciers made by NASA and similar entities; eye-witness, expert accounts and youth-produced documentaries designed for United Nations delegates to the annual COP events such as the Youth Climate Report; Please Help the World, the dystopian cli-fi narrative produced for the UN’s COP 15; and Isuma TV’s streaming of works by Indigenous practitioners in Nunavut.

A Rule Follower, a Challenger, or a Learner? Recasting China’s Engagement in the Arctic

2018 ◽  
Vol 9 (1) ◽  
pp. 201-242
Author(s):  
Yuanyuan Ren ◽  
Dan Liu
Keyword(s):  
Climate Change ◽  
International Law ◽  
Technological Innovation ◽  
Arctic Region ◽  
Economic Globalization ◽  
The Arctic ◽  
Full Account ◽  
Commercial Activities ◽  
Participant Role ◽  
The Arctic Region

In an era of climate change, economic globalization, and technological innovation, the Arctic region has been increasingly open to competing jurisdictional claims, commercial activities, and outside players. In the meantime, China’s engagement in the Arctic has drawn great attention. While some Arctic commentators are concerned about China as a threat to the region, many Chinese officials and scholars tend to portray China as a “rule-follower” in the Arctic. However, this “rule-follower” image fails to take full account of the evolving nature of Arctic governance and Arctic international law. This paper recasts China’s role in the Arctic. It argues that, to fulfill a “constructive participant” role in Arctic development, China can participate as a rule follower, a constructive challenger, and a keen learner concurrently, depending on the different issue-areas involved.

scholarly journals Technology for developing a prototype of an information system for monitoring remote sensing data for the arctic region

2021 ◽  
Author(s):  
M. Bizyukin ◽  
◽  
G. V. Abrahamyan
Keyword(s):  
Remote Sensing ◽  
Information System ◽  
Russian Federation ◽  
Remote Sensing Data ◽  
Arctic Region ◽  
Use Cases ◽  
The Arctic ◽  
Sensing Data ◽  
The Russian Federation ◽  
The Arctic Region

The work is aimed at developing a model of an information system for the analysis and monitoring of remote sensing data by the example of processing hyper- and multispectral satellite images, which are widely used to analyze the state of static and dynamic objects in the Arctic region of the Russian Federation. For automatic analysis and decryption of Arctic data in the development of the model, methods of high-performance computing, radiometric calibration, filtering and clustering of images, as well as intelligent data processing methods using deep learning convolutional neural networks were used. Object-oriented design and united modeling language notation were used to develop the model. A data-level model, a conceptual model of the structure of system modules, including a resource storage center, a resource and results management center, and a presentation-level interface have been developed. To develop a diagram of the use cases of the information system, the structure of actors, use cases and their interrelations were identified. The logical model of the information system was created based on a class diagram consisting of the Resource and Results Manager Center, Intellectual Information System, Functional Neural Modules packages. The practical significance of the study is due to the fact that the results obtained will allow the development of a prototype of an information system that can be used for effective monitoring of “useful data" of the Arctic region of the Russian Federation, as well as to automate the processes of analysis, updating, storage and processing of data from objects in various areas of the Arctic infrastructure.

scholarly journals SEISMICITY of the ARCTIC in 2015

2021 ◽  
pp. 210-216
Author(s):  
A. Morozov ◽  
G. Avetisov ◽  
G. Antonovskaya ◽  
V. Asming ◽  
S. Baranov ◽  
...  
Keyword(s):  
Seismic Station ◽  
Arctic Region ◽  
The Arctic ◽  
Earthquake Catalog ◽  
Svalbard Archipelago ◽  
Ocean Ridges ◽  
The North ◽  
Franz Josef Land ◽  
Barents And Kara Seas ◽  
The Arctic Region

The article provides an overview and analysis of seismicity within the boundaries of the Arctic region for 2015, a description of seismic station networks, and processing methods. The catalog of earthquakes in the Arctic region was compiled on the basis of catalogs of several organizations and seismological centers. In total, 334 earthquakes are included in the earthquake catalog. Most of the earthquakes that occurred in 2015, including all the strongest earthquakes, were located within the mid-ocean ridges of Mon, Knipovich and Gakkel. In the offshore territories, most of the earthquakes were confined to the Svalbard archipelago, in particular, to the seismically active zone in the Sturfjord strait. The renewal of instrumental seismological observations in 2011 (station ZFI) on Alexandra Land Island in the Franz Josef Land archipelago made it possible to record weak earthquakes in the north of the shelf of the Barents and Kara Seas. For twelve earthquakes, the focal mechanism parameters are presented according to the Global CMT catalog.

scholarly journals Accuracy Evaluation and Consistency Analysis of Four Global Land Cover Products in the Arctic Region

2019 ◽  
Vol 11 (12) ◽  
pp. 1396 ◽  
Author(s):  
Li Liang ◽  
Qingsheng Liu ◽  
Gaohuan Liu ◽  
He Li ◽  
Chong Huang
Keyword(s):  
Climate Change ◽  
Land Cover ◽  
Classification Accuracy ◽  
Urban Areas ◽  
Arctic Region ◽  
The Arctic ◽  
Global Land Cover ◽  
Global Land ◽  
The Arctic Region

Land cover is a fundamental component of crucial importance in the earth sciences. To date, many excellent international teams have created a variety of land cover products covering the entire globe. To provide a reference for researchers studying the Arctic, this paper evaluates four commonly used land cover products. First, we compare and analyze the four land cover products from the perspectives of land cover type, distribution and spatial heterogeneity. Second, we evaluate the accuracy of such products by using two sets of sample points collected from the Arctic region. Finally, we obtain the spatial consistency distribution of the products by means of superposition analysis. The results show the following: (a) among the four land cover products, Climate Change Initiative Land Cover (CCI-LC) has the highest overall accuracy (63.5%) in the Arctic region, GlobeLand30 has an overall accuracy of 62.2% and the overall accuracy of the Global Land Cover by the National Mapping Organization (GLCNMO) is only 48.8%. When applied in the Arctic region, the overall accuracy of the Moderate Resolution Imaging Spectroradiometer (MODIS) is only 29.5% due to significant variances. Therefore, MODIS and GLCNMO are not recommended in Arctic-related research as their use may lead to major errors. (b) An evaluation of the consistency of the four products indicates that the classification of the large-scale homogeneous regions in the Arctic yields satisfactory results, whereas the classification results in the forest–tundra ecotone are unsatisfactory. The results serve as a reference for future research. (c) Among the four products, GlobeLand30 is the best choice for analyzing finely divided and unevenly distributed surface features such as waters, urban areas and cropland. Climate Change Initiative Land Cover (CCI-LC) has the highest overall accuracy, and its classification accuracy is relatively higher for forests, shrubs, sparse vegetation, snow/ice and water. GlobeLand30 and CCI-LC do not vary much from each other in terms of overall accuracy. They differ the most in the classification accuracy of shrub-covered land; CCI-LC performed better than GlobeLand30 in the classification of shrub-covered land, whereas the latter obtained higher accuracy than that of the former in the classification of urban areas and cropland.

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