scholarly journals Results of sea level studies at RSHU

2020 ◽  
pp. 269-305
Author(s):  
V.N. Malinin ◽  
S.M. Gordeeva ◽  
Yu.V. Mitina ◽  
O.I. Shevchuk

Study of sea level is being developed at RSHU in several directions: global, regional and local. The global one includes the study of the patterns of interannual fluctuations of the global sea level (GLS), identification of their genesis and development of a set of methods for its long-term forecast. Two approaches to the genesis of GLS are considered. In foreign studies, changes in GLS are determined by changes in the water mass of various cryosphere components, land water reserves and steric level fluctuations. Another approach, implemented at RSHU, is to assess contributions of various factors using the equation of the freshwater balance of the World Ocean as the sum of eustatic and steric factors. A physical-statistical method for two-decade GLS forecasting, based on delay in the GLS response to air temperature over the ocean, has been developed, as well as the GLS projections at the end of the century for climatic scenarios according to the CMIP5 project have been provided. In the regional context, the main attention is paid to identifying the genesis of the interannual variability of the Caspian Sea level with the aim of its long-term forecasting. The entire chain of cause-and-effect relationships in the North Atlantic-atmosphere-Volga basin-Caspian level system is discussed. It has been established that, as a result of the intensification of cyclonic activity in the North Atlantic, especially in the Norwegian Sea, caused by the processes of large-scale interaction between the ocean and the atmosphere, there is an increase in evaporation and in the zonal transfer of water vapour to Europe and then to the Volga basin. Therefore, more precipitation falls in the runoff-forming zone of the basin, the annual runoff of the Volga and the level of the Caspian Sea increasing. The reverse is observed with weakening of cyclonic activity in the North Atlantic. In view of this, the level of the Caspian Sea is an integral indicator of largescale moisture exchange in the ocean-atmosphere-land system. The article discusses the features of interannual sea level fluctuations in Kronstadt since 1836. A simple two-parameter model for forecasting sea level by the end of the 21st century is proposed for major climate scenarios, the predictors being the GSL and the North Atlantic Oscillation. According to the most realistic forecast, the level in Kronstadt may rise to 34-59 cm (Baltic system) by the end of the century, while according to the “pessimistic” one — to 80-90 cm (Baltic system). The estimates of the extreme storm surge at which the level rise north of the Gorskaya can reach 600 cm (Baltic system) are given. The effect of flooding from storm surges is especially strong near Sestroretsk. The total area of possible flooding of the Kurortny district at a 4-m high surge wave exceeds 1260 hectares, all the beaches being completely lost. The trajectories of flood cyclones and their role for periods of climate warming and cooling are considered

Water ◽  
2012 ◽  
Vol 4 (1) ◽  
pp. 170-195 ◽  
Author(s):  
Sönke Dangendorf ◽  
Thomas Wahl ◽  
Hartmut Hein ◽  
Jürgen Jensen ◽  
Stephan Mai ◽  
...  

2015 ◽  
Vol 42 (4) ◽  
pp. 525-534 ◽  
Author(s):  
G. N. Panin ◽  
T. Yu. Vyruchalkina ◽  
I. V. Solomonova

Author(s):  
Robert H. Ellison

Prompted by the convulsions of the late eighteenth century and inspired by the expansion of evangelicalism across the North Atlantic world, Protestant Dissenters from the 1790s eagerly subscribed to a millennial vision of a world transformed through missionary activism and religious revival. Voluntary societies proliferated in the early nineteenth century to spread the gospel and transform society at home and overseas. In doing so, they engaged many thousands of converts who felt the call to share their experience of personal conversion with others. Though social respectability and business methods became a notable feature of Victorian Nonconformity, the religious populism of the earlier period did not disappear and religious revival remained a key component of Dissenting experience. The impact of this revitalization was mixed. On the one hand, growth was not sustained in the long term and, to some extent, involvement in interdenominational activity undermined denominational identity; on the other hand, Nonconformists gained a social and political prominence they had not enjoyed since the middle of the seventeenth century and their efforts laid the basis for the twentieth-century explosion of evangelicalism in Africa, Asia, and South America.


2021 ◽  
Author(s):  
Alvise Aranyossy ◽  
Sebastian Brune ◽  
Lara Hellmich ◽  
Johanna Baehr

<p>We analyse the connections between the wintertime North Atlantic Oscillation (NAO), the eddy-driven jet stream with the mid-latitude cyclonic activity over the North Atlantic and Europe. We investigate, through the comparison against ECMWF ERA5 and hindcast simulations from the Max Planck Institute Earth System Model (MPI-ESM), the potential for enhancement of the seasonal prediction skill of the Eddy Kinetic Energy (EKE) by accounting for the connections between large-scale climate and the regional cyclonic activity. Our analysis focuses on the wintertime months (December-March) in the 1979-2019 period, with seasonal predictions initialized every November 1st. We calculate EKE from wind speeds at 250 hPa, which we use as a proxy for cyclonic activity. The zonal and meridional wind speeds are bandpass filtered with a cut-off at 3-10 days to fit with the average lifespan of mid-latitude cyclones. </p><p>Preliminary results suggest that in ERA5, major positive anomalies in EKE, both in quantity and duration, are correlated with a northern position of the jet stream and a positive phase of the NAO. Apparently, a deepened Icelandic low-pressure system offers favourable conditions for mid-latitude cyclones in terms of growth and average lifespan. In contrast, negative anomalies in EKE over the North Atlantic and Central Europe are associated with a more equatorward jet stream, these are also linked to a negative phase of the NAO.  Thus, in ERA5, the eddy-driven jet stream and the NAO play a significant role in the spatial and temporal distribution of wintertime mid-latitude cyclonic activity over the North Atlantic and Europe. We extend this connection to the MPI-ESM hindcast simulations and present an analysis of their predictive skill of EKE for wintertime months.</p>


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