First Polish Greenland Expedition 1937: on the 80th anniversary of the event

Polar Record ◽  
2017 ◽  
Vol 53 (4) ◽  
pp. 358-363
Author(s):  
Krzysztof Migała ◽  
Tymoteusz Sawiński ◽  
Jacek Piasecki

ABSTRACTThis paper describes the first Polish expedition to Greenland in 1937. The fieldwork was carried out in western Greenland at the eastern edge of Arfersiorfik Fjord between Disko Bay in the north and Nordre Strömfjord in the south. The main goal was to undertake a comprehensive study of a fragment of the Greenland ice sheet edge and its foreland focusing on a cartographic survey. The first ever map of this region entitled The Polish expedition to give new names. In the post-war history, expedition members exerted great influence on the development of Polish polar research.

2014 ◽  
Vol 119 (2) ◽  
pp. 631-645 ◽  
Author(s):  
Mark E. Inall ◽  
Tavi Murray ◽  
Finlo R. Cottier ◽  
Kilian Scharrer ◽  
Timothy J. Boyd ◽  
...  

2021 ◽  
Vol 9 (11) ◽  
pp. 1258
Author(s):  
Viet Thanh Nguyen ◽  
Minh Tuan Vu ◽  
Chi Zhang

Two-dimensional models of large spatial domain including Cua Lo and Cua Hoi estuaries in Nghe An province, Vietnam, were established, calibrated, and verified with the observed data of tidal level, wave height, wave period, wave direction, and suspended sediment concentration. The model was then applied to investigate the hydrodynamics, cohesive sediment transport, and the morphodynamics feedbacks between two estuaries. Results reveal opposite patterns of nearshore currents affected by monsoons, which flow from the north to the south during the northeast (NE) monsoon and from the south to the north during the southeast (SE) monsoon. The spectral wave model results indicate that wave climate is the main control of the sediment transport in the study area. In the NE monsoon, sediment from Cua Lo port transported to the south generates the sand bar in the northern bank of the Cua Hoi estuary, while sediment from Cua Hoi cannot be carried to the Cua Lo estuary due to the presence of Hon Ngu Island and Lan Chau headland. As a result, the longshore sediment transport from the Cua Hoi estuary to the Cua Lo estuary is reduced and interrupted. The growth and degradation of the sand bars at the Cua Hoi estuary have a great influence on the stability of the navigation channel to Ben Thuy port as well as flood drainage of Lam River.


2007 ◽  
Vol 1 (1) ◽  
pp. 41-76 ◽  
Author(s):  
R. Greve ◽  
S. Otsu

Abstract. The north-east Greenland ice stream (NEGIS) was discovered as a large fast-flow feature of the Greenland ice sheet by synthetic aperture radar (SAR) imaginary of the ERS-1 satellite. In this study, the NEGIS is implemented in the dynamic/thermodynamic, large-scale ice-sheet model SICOPOLIS (Simulation Code for POLythermal Ice Sheets). In the first step, we simulate the evolution of the ice sheet on a 10-km grid for the period from 250 ka ago until today, driven by a climatology reconstructed from a combination of present-day observations and GCM results for the past. We assume that the NEGIS area is characterized by enhanced basal sliding compared to the "normal", slowly-flowing areas of the ice sheet, and find that the misfit between simulated and observed ice thicknesses and surface velocities is minimized for a sliding enhancement by the factor three. In the second step, the consequences of the NEGIS, and also of surface-meltwater-induced acceleration of basal sliding, for the possible decay of the Greenland ice sheet in future warming climates are investigated. It is demonstrated that the ice sheet is generally very susceptible to global warming on time-scales of centuries and that surface-meltwater-induced acceleration of basal sliding can speed up the decay significantly, whereas the NEGIS is not likely to dynamically destabilize the ice sheet as a whole.


2021 ◽  
Author(s):  
Sophie Stolzenberger ◽  
Roelof Rietbroek ◽  
Claudia Wekerle ◽  
Bernd Uebbing ◽  
Jürgen Kusche

<p>The impact of Greenland freshwater on oceanic variables in the North Atlantic has been controversially discussed in the past. Within the framework of the German research project GROCE (Greenland Ice Sheet Ocean Interaction), we present a comprehensive study using ocean modelling results including and excluding the Greenland freshwater flux. The aim of this study is whether signatures of Greenland ice sheet melting found in ocean model simulations are visible in the observations. Therefore, we estimate changes in temperature, salinity, steric heights and sea level anomalies since the 1990s. The observational database includes altimetric and gravimetric satellite data as well as Argo floats. We will discuss similarities/differences between model simulations and observations for smaller regions around Greenland in the North Atlantic. As these experiments are available for two different horizontal resolutions, we will furthermore be able to assess the effects of an increased model resolution.</p>


2021 ◽  
Author(s):  
Brian Crow ◽  
Matthias Prange ◽  
Michael Schulz

<p>Historical estimates of the melt rate and extent of the Greenland ice sheet (GrIS) are poorly constrained, due both to incomplete understanding of relevant ice dynamics and the magnitude of forcing acting upon the ice sheet (e.g., Alley et al. 2010). Previous assessments of the Marine Isotope Stage 11 (MIS-11) interglacial period have determined it was likely one of the warmest and longest interglacial periods of the past 800 kyr, leading to melt of at least half the present-day volume of the Greenland ice sheet (Robinson et al. 2017). An enhanced Atlantic meridional overturning circulation (AMOC) is commonly cited as sustaining the anomalous warmth across the North Atlantic and Greenland (e.g., Rachmayani et al. 2017), but little is known about potential atmospheric contributions. Paleorecords from this period are sparse, and detailed climate modelling studies of this period have been heretofore very limited. The climatic conditions over Greenland and the North Atlantic region, and how they may have contributed to the melt of the GrIS during MIS-11, are therefore not well understood. By utilizing climate simulations with the Community Earth System Model (CESM), our study indicates that changes in atmospheric eddy behavior, including eddy fluxes of heat and precipitation, made significant contributions to the negative mass balance conditions over the GrIS during the MIS-11 interglacial. Thus, accounting for the effects of atmospheric feedbacks in a warmer-than-present climate is a necessary component for future analyses attempting to better constrain the extent and rate of melt of the GrIS.</p>


2020 ◽  
Vol 12 (19) ◽  
pp. 3250
Author(s):  
Fang Zou ◽  
Robert Tenzer ◽  
Hok Sum Fok ◽  
Janet E. Nichol

Although a significant effort has been dedicated to studying changes in the mass budget of the Greenland Ice Sheet (GrIS), mechanisms behind these changes are not yet fully understood. In this study, we address this issue by investigating the link between climate controls and mass changes of the GrIS between August 2002 and June 2017. We estimate the GrIS mass changes based on averaging the Gravity Recovery and Climate Experiment (GRACE) monthly gravity field solutions from four processing data centers. We then investigate the possible impact of different climate variables on the GrIS mass changes using the North Atlantic Oscillation (NAO), temperature, precipitation, and the 700 hPa wind retrieved from the ERA-5 reanalysis. Results indicate a decrease of −267.77 ± 32.67 Gt/yr in the total mass of the GrIS over the 16-year period. By quantifying the relationship between climate controls and mass changes, we observe that mass changes in different parts of Greenland have varying sensitivity to climate controls. The NAO mainly controls mass changes in west Greenland, where the summertime NAO modulations have a greater impact on the summer mass loss than the wintertime NAO modulations have on the winter mass gain. The GrIS mass changes are correlated spatially with summer temperature, especially in southwest Greenland. Mass balance changes in northwest Greenland are mostly affected by wind anomalies. These new findings based on wind anomalies indicate that the summer atmospheric circulation anomalies control surface temperature and snow precipitation and consequently affect mass changes in different parts of Greenland.


1917 ◽  
Vol 4 (6) ◽  
pp. 241-245 ◽  
Author(s):  
C. T. Trechmann

The controversy which has arisen in recent years in New Zealand regarding the problem of the Pleistocene glaciation of that country resolves itself into the two following main questions:—1. Was there any glaciation in the North Island?2. Was there an ice-sheet covering the South Island?


2008 ◽  
Vol 54 (185) ◽  
pp. 203-212 ◽  
Author(s):  
Robert Thomas ◽  
Curt Davis ◽  
Earl Frederick ◽  
William Krabill ◽  
Yonghong Li ◽  
...  

AbstractWe compare rates of surface-elevation change on the Greenland ice sheet derived from European Remote-sensing Satellite-2 (ERS-2) radar-altimeter data with those obtained from laser-altimeter data collected over nearly the same time periods. Radar-altimeter data show more rapid thickening (9 ± 1 cm a−1 above 1500 m elevation in the north, and 3 ± 1 cm a−1 above 2000 m in the south) than the laser estimates, possibly caused by a lifting of the radar-reflection horizon associated with changes in the snowpack, such as those caused by progressively increased surface melting, as summer temperatures rise. Over all the ice sheet above 2000 m, this results in an ERS-derived volume balance ∼75 ± 15 km3 a−1 more positive than that from laser data. This bias between laser and radar estimates of elevation change varies spatially and temporally, so cannot at present be corrected without independent surveys such as those presented here. At lower elevations, comparison of detailed repeat laser surveys over Jakobshavn Isbræ with ERS results over the same time interval shows substantial ERS underestimation of ice-thinning rates. This results partly from missing data because of ‘bad’ radar waveforms over the very rough surface topography, and partly from the tendency for large radar footprints to sample preferentially local high points in the topography, thus missing regions of most rapid thinning along glacier depressions.


2015 ◽  
Vol 128 ◽  
pp. 61-71 ◽  
Author(s):  
Ki-Weon Seo ◽  
Duane E. Waliser ◽  
Choon-Ki Lee ◽  
Baijun Tian ◽  
Ted Scambos ◽  
...  

2018 ◽  
Vol 57 (4) ◽  
pp. 921-935 ◽  
Author(s):  
Jonathan Edwards-Opperman ◽  
Steven Cavallo ◽  
David Turner

AbstractStratiform liquid-bearing clouds (LBCs), defined herein as either pure liquid or mixed-phase clouds, have a large impact on the surface radiation budget across the Arctic. LBCs lasting at least 6 h are observed at Summit, Greenland, year-round with a maximum in occurrence during summer. Mean cloud-base height is below 1 km for 85% of LBC cases identified, 59% have mean liquid water path (LWP) values between 10 and 40 g m−2, and most produce sporadic light ice-phase precipitation. During their occurrence, the atmosphere above the ice sheet is anomalously warm and moist, with southerly winds observed over much of the ice sheet, including at Summit. LBCs that occur when the North Atlantic Oscillation (NAO) is in the negative phase correspond to strong ridging centered over the Greenland Ice Sheet (GIS), allowing for southwesterly flow over the GIS toward Summit. During the positive phase of the NAO, the occurrence of LBCs corresponds to a cyclone located off the southeastern coast of the ice sheet, which leads to easterly-to-southeasterly flow toward Summit. Furthermore, air parcels at Summit frequently originate from below the elevation of Summit, indicating that orographic lift along the ice sheet is a factor in the occurrence of LBCs at Summit. LBCs are more frequently observed during the negative NAO, and both the LWP and precipitation rate are larger in LBCs occurring during this phase. Mean LWP in LBCs occurring during the negative NAO is 15 g m−2 larger than in LBCs occurring during the positive phase.


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