scholarly journals Review of Survey activities 2004

2005 ◽  
Vol 7 ◽  
pp. 1-7
Author(s):  
Kai Sørensen

The Review of Survey activities presents a selection of 18 papers reflecting the wide spectrum of activities of the Geological Survey of Denmark and Greenland, from the microbial to the plate tectonic level.Activities in Denmark: The Survey's activities in Denmark are documented by 11 papers. The main themes are petroleum- and groundwater-related topics and Quaternary geology but neotectonics of the Baltic Shield and new methods in provenance studies of sandstones are also touched upon.Activities in Greenland: The Survey's activities in Greenland and the North Atlantic are covered by six articles focusing on climate research, the mineral potential of the Precambrian basement terranes in West Greenland and on the possibility of exploiting dimension stones.Other countries: During 2004, the Survey carried out work in more than 20 countries outside Denmark, Greenland and the Faroe Islands. In this report a project on developing small-scale mining in Mongolia and Kyrgyzstan is described.

2021 ◽  
pp. 003022282110241
Author(s):  
Elsa J. D. Johannesen ◽  
Ása Róin

Studies have shown that losing a spouse can cause both physical and mental suffering for the bereaved. This qualitative study aimed to gather knowledge about how men and women in the Faroe Islands, a small-scale society in the North Atlantic Ocean, managed the transition to widowhood. Five women and three men were interviewed, their age varying from 67 to 74 years. A hermeneutic analytic method was applied. Our findings showed that managing the transition to widowhood followed two tracks, namely the process of loss and the process of restoration. For participants locked in either process, the transition caused severe disruption in daily living, while participants who managed to oscillate between the two processes appeared to manage the transition to widowhood and get on with their lives. Our findings, and those from other studies, point to the need to offer structured individual support for people who have lost their life partner.


2017 ◽  
Vol 47 (10) ◽  
pp. 2419-2427 ◽  
Author(s):  
Daniel B. Whitt ◽  
John R. Taylor

AbstractAtmospheric storms are an important driver of changes in upper-ocean stratification and small-scale (1–100 m) turbulence. Yet, the modifying effects of submesoscale (0.1–10 km) motions in the ocean mixed layer on stratification and small-scale turbulence during a storm are not well understood. Here, large-eddy simulations are used to study the coupled response of submesoscale and small-scale turbulence to the passage of an idealized autumn storm, with a wind stress representative of a storm observed in the North Atlantic above the Porcupine Abyssal Plain. Because of a relatively shallow mixed layer and a strong downfront wind, existing scaling theory predicts that submesoscales should be unable to restratify the mixed layer during the storm. In contrast, the simulations reveal a persistent and strong mean stratification in the mixed layer both during and after the storm. In addition, the mean dissipation rate remains elevated throughout the mixed layer during the storm, despite the strong mean stratification. These results are attributed to strong spatial variability in stratification and small-scale turbulence at the submesoscale and have important implications for sampling and modeling submesoscales and their effects on stratification and turbulence in the upper ocean.


1968 ◽  
Vol 25 (6) ◽  
pp. 1269-1284 ◽  
Author(s):  
Adam S. Bursa

Starch observed in arctic waters of Canada, in the Baltic and Mediterranean seas, in the North Atlantic and Indian oceans, and in the waters about Bermuda, the Virgin Islands, and Jamaica is formed mostly in Gymnodinioideae, benthic algae, and higher aquatic plants and rarely in planktonic Chlorophyceae. In these phytoflagellates the fragile pellicle breaks when there are critical changes in salinity, temperature, or pressure and is subsequently decomposed by bacteria. The starch retains its shape after destruction of the protoplast, and accumulates in large quantities in aquatic habitats. Standing crops of free starch grains mark past blooms and mass mortalities of phytoplankton. The largest potato-like starch grains found in the oceans appear to be derived from the ocellar lenses of Warnoviaceae.Though Protozoa and various herbivores may ingest free planktonic starch, they were not observed to digest it. Large standing crops of starch and monosaccharides derived from amylolysis may affect nutrition in some animals, and influence the optical and chemical properties of sea water. Amylogenesis in some dinoflagellates starts from chondriosomes which are specialized in this process. In Prorocentrideae starch is formed within the ectoplasmic reticulum.


2019 ◽  
Vol 116 (27) ◽  
pp. 13227-13232 ◽  
Author(s):  
Petar Glišović ◽  
Alessandro M. Forte

The North Atlantic Igneous Province (NAIP) erupted in two major pulses that coincide with the continental breakup and the opening of the North Atlantic Ocean over a period from 62 to 54 Ma. The unknown mantle structure under the North Atlantic during the Paleocene represents a major missing link in deciphering the geodynamic causes of this event. To address this outstanding challenge, we use a back-and-forth iterative method for time-reversed global convection modeling over the Cenozoic Era which incorporates models of present-day tomography-based mantle heterogeneity. We find that the Paleocene mantle under the North Atlantic is characterized by two major low-density plumes in the lower mantle: one beneath Greenland and another beneath the Azores. These strong lower-mantle upwellings generate small-scale hot upwellings and cold downwellings in the upper mantle. The upwellings are dispersed sources of magmatism and topographic uplift that were active on the rifted margins of the North Atlantic during the formation of the NAIP. While most studies of the Paleocene evolution of the North Atlantic have focused on the proto-Icelandic plume, our Cenozoic reconstructions reveal the equally important dynamics of a hot, buoyant, mantle-wide upwelling below the Azores.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Reindert J. Haarsma ◽  
Javier García-Serrano ◽  
Chloé Prodhomme ◽  
Omar Bellprat ◽  
Paolo Davini ◽  
...  

Abstract Northern Hemisphere western boundary currents, like the Gulf Stream, are key regions for cyclogenesis affecting large-scale atmospheric circulation. Recent observations and model simulations with high-temporal and -spatial resolution have provided evidence that the associated ocean fronts locally affect troposphere dynamics. A coherent view of how this affects the mean climate and its variability is, however, lacking. In particular the separate role of resolved ocean and atmosphere dynamics in shaping the atmospheric circulation is still largely unknown. Here we demonstrate for the first time, by using coupled seasonal forecast experiments at different resolutions, that resolving meso-scale oceanic variability in the Gulf Stream region strongly affects mid-latitude interannual atmospheric variability, including the North Atlantic Oscillation. Its impact on climatology, however, is minor. Increasing atmosphere resolution to meso-scale, on the other hand, strongly affects mean climate but moderately its variability. We also find that regional predictability relies on adequately resolving small-scale atmospheric processes, while resolving small-scale oceanic processes acts as an unpredictable source of noise, except for the North Atlantic storm-track where the forcing of the atmosphere translates into skillful predictions.


Boreas ◽  
2008 ◽  
Vol 35 (1) ◽  
pp. 23-34 ◽  
Author(s):  
CAMILLA S. ANDRESEN ◽  
SVANTE BJÖRCK ◽  
MATS RUNDGREN ◽  
DANIEL J. CONLEY ◽  
CATHERINE JESSEN

2007 ◽  
Vol 38 (4-5) ◽  
pp. 413-423 ◽  
Author(s):  
I. Danilovich ◽  
D. Wrzesiński ◽  
L. Nekrasova

The dynamics of the North Atlantic Oscillation (NAO) and river runoff in the Belarus part of the Baltic Sea basin have been studied. Correlation coefficients between NAO indices and monthly, seasonal and annual discharges were calculated, changes in the runoff in the opposite stages of NAO and its intra-annual distribution were analysed, and runoff trends for different time series were investigated. The closest connection could be observed between NAO indices for December–March and the runoff of Belarusian rivers in the Baltic basin. The highest correlation coefficients were calculated for winter and spring months. The intra-annual runoff differs in opposite stages of the North Atlantic Oscillation. The most significant increase of monthly runoff was observed after 1961. There was a positive trend of runoff at the beginning of the year, but a negative one in the summer and autumn months.


2020 ◽  
Vol 8 (4) ◽  
pp. SQ105-SQ114
Author(s):  
Tor Arne Johansen ◽  
Bent Ole Ruud ◽  
Tormod Henningsen ◽  
Marco Brönner

Andøya is an island in the north of Norway. On its eastern side, it contains a local downfaulted basin of Mesozoic sediments sheltered from erosion during subsequent periods of Pleistocene glaciation. The sediments were deposited before the North Atlantic rifting and partly overlie weathered basement. We have recently carried out seismic surveying to better understand the geometry and seismic responses of the basin system. Extensive civil infrastructure and wet mire made the study area challenging for seismic exploration. We shot the survey lines at wet mire with detonating cord during winter when the mire was frozen. In the summer, we conducted seismic surveying along road shoulders with a small-scale vibrator. The seismic processing was particularly challenging due to the influence of traffic noise, heterogeneous near-surface conditions, and large seismic velocity contrasts. We interpreted the seismic lines in integration with other geophysical data and well logs to obtain a consistent and best possible seismic model of the basin. Our interpretation indicates a reorganization of the regional paleostress regime that took place during the continental breakup in the Eocene. In spite of severe obstacles for seismic surveying of the area, our results honor the robustness of the seismic method for subsurface imaging.


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