scholarly journals On the Rivers in the Euro-Atlantic Sky

2020 ◽  
Author(s):  
Venugopal Thandlam ◽  
Anna Rutgersson ◽  
Erik Sahlee
Keyword(s):  
Water Vapour ◽  
North Atlantic ◽  
Western Europe ◽  
Decadal Variability ◽  
Moisture Flux ◽  
Lower Atmosphere ◽  
Specific Humidity ◽  
Spatiotemporal Variability ◽  
The North ◽  
The North Atlantic

Abstract We study the spatiotemporal variability of Atmospheric Rivers (ARs) over Euro-Atlantic region using long-term reanalysis datasets. Winds, temperature and specific humidity at different pressure levels during 1979-2018 are used to study the water vapour transport integrated between 1000-300 hPa (IVT300) as a proxy to ARs. The intensity of ARs in the North Atlantic has been increasing in recent times (2009-2018) with large decadal variability and poleward shift (~5o towards the North) in landfall (1999-2018). Significant bias shown by different reanalysis products in IVT300 compared to ERA5 data is attributed to bias in specific humidity and winds. Different reanalysis datasets show similar spatial patterns of IVT300 in mapping ARs but has a bias of around 40-60 kgm-1s-1 compared to ERA5. The magnitude of winds and specific humidity in the lower atmosphere (below 750 hPa) dominates the total column water vapour and intensity of Ars in the north Atlantic. IVT300 in all reanalysis datasets in the North Atlantic show a standard deviation of 200 kgm-1s-1 which is around 60% of the IVT300 climatology (>300 kgm-1s-1). Though ARs have higher frequency of landfalling over Western Europe in winter half-year (WHY); the intensity of IVT300 in winter is 3% lower than the annual mean. On the other hand, lower frequency of ARs in summer half-year (SHY) shows 3% higher intensity than the annual mean. There is a significant impact of the North Atlantic Oscillation (NAO) and Scandinavian blocking on the location of landfall of ARs. Furthermore, there is a strong latitudinal dependence of the source of moisture flux in the open ocean, contributing to the formation and enhancing AR's strength.

On the Rivers in the Euro-Atlantic Sky

2020 ◽  
Author(s):  
Venugopal Thandlam ◽  
Anna Rutgersson ◽  
Erik Sahlee
Keyword(s):  
Water Vapour ◽  
North Atlantic ◽  
Western Europe ◽  
Decadal Variability ◽  
Moisture Flux ◽  
Lower Atmosphere ◽  
Specific Humidity ◽  
Spatiotemporal Variability ◽  
The North ◽  
The North Atlantic

Abstract We study and revisit the Atmospheric Rivers (AR) over Euro-Atlantic sky using long term reanalysis datasets and widely used methods and parameters. The atmospheric winds, temperature and specific humidity at different pressure levels during 1979-2018 were used to study the spatiotemporal variability of water vapour transport integrated between 1000-300 hPa (IVT300) as a proxy to ARs. The standard deviation (200 kgm-1s-1) of ARs is around 60% of the climatology (>300 kgm-1s-1) in all reanalysis datasets in the North Atlantic. High frequency of ARs over western Europe in winter half-year (WHY) has 6% lower intensity compared to the low frequency of ARs in summer half-year (SHY) with 3% higher intensity than the annual mean. The intensity of ARs in the North Atlantic has been increasing in recent times with large decadal variability and poleward shift in landfalling. The magnitude of atmospheric parameters in the lower atmosphere below 750 hPa dominates the total column water vapour and intensity of ARs. There is a significant impact of the North Atlantic Oscillation and Scandinavian blocking on the location of landfalling of ARs and latitudinal dependence of the source of moisture flux in the open ocean contributing to the formation and enhancing ARs strength.

scholarly journals On the Rivers in the Euro-Atlantic Sky

2020 ◽  
Author(s):  
Venugopal Thandlam ◽  
Anna Rutgersson ◽  
Erik Sahlee
Keyword(s):  
Water Vapour ◽  
North Atlantic ◽  
Western Europe ◽  
Decadal Variability ◽  
Moisture Flux ◽  
Lower Atmosphere ◽  
Specific Humidity ◽  
Spatiotemporal Variability ◽  
The North ◽  
The North Atlantic

Abstract We study and revisit the Atmospheric Rivers (AR) over Euro-Atlantic sky using long term reanalysis datasets and widely used methods and parameters. The atmospheric winds, temperature and specific humidity at different pressure levels during 1979-2018 were used to study the spatiotemporal variability of water vapour transport integrated between 1000-300 hPa (IVT300) as a proxy to ARs. The standard deviation (200 kgm-1s-1) of ARs is around 60% of the climatology (>300 kgm-1s-1) in all reanalysis datasets in the North Atlantic. High frequency of ARs over western Europe in winter half-year (WHY) has 6% lower intensity compared to the low frequency of ARs in summer half-year (SHY) with 3% higher intensity than the annual mean. The intensity of ARs in the North Atlantic has been increasing in recent times with large decadal variability and poleward shift in landfalling. The magnitude of atmospheric parameters in the lower atmosphere below 750 hPa dominates the total column water vapour and intensity of ARs. There is a significant impact of the North Atlantic Oscillation and Scandinavian blocking on the location of landfalling of ARs and latitudinal dependence of the source of moisture flux in the open ocean contributing to the formation and enhancing ARs strength.

Near-surface wind speeds in ERA5: Climatology, decadal variability and long-term trends

2021 ◽  
Author(s):  
Terhi K. Laurila ◽  
Victoria A. Sinclair ◽  
Hilppa Gregow
Keyword(s):  
Iberian Peninsula ◽  
North Atlantic ◽  
Decadal Variability ◽  
Surface Wind ◽  
Northern Europe ◽  
Near Surface ◽  
Wind Speeds ◽  
The North ◽  
The North Atlantic

<p>The knowledge of long-term climate and variability of near-surface wind speeds is essential and widely used among meteorologists, climate scientists and in industries such as wind energy and forestry. The new high-resolution ERA5 reanalysis from the European Centre for Medium-Range Weather Forecasts (ECMWF) will likely be used as a reference in future climate projections and in many wind-related applications. Hence, it is important to know what is the mean climate and variability of wind speeds in ERA5.</p><p>We present the monthly 10-m wind speed climate and decadal variability in the North Atlantic and Europe during the 40-year period (1979-2018) based on ERA5. In addition, we examine temporal time series and possible trends in three locations: the central North Atlantic, Finland and Iberian Peninsula. Moreover, we investigate what are the physical reasons for the decadal changes in 10-m wind speeds.</p><p>The 40-year mean and the 98th percentile wind speeds show a distinct contrast between land and sea with the strongest winds over the ocean and a seasonal variation with the strongest winds during winter time. The winds have the highest values and variabilities associated with storm tracks and local wind phenomena such as the mistral. To investigate the extremeness of the winds, we defined an extreme find factor (EWF) which is the ratio between the 98th percentile and mean wind speeds. The EWF is higher in southern Europe than in northern Europe during all months. Mostly no statistically significant linear trends of 10-m wind speeds were found in the 40-year period in the three locations and the annual and decadal variability was large.</p><p>The windiest decade in northern Europe was the 1990s and in southern Europe the 1980s and 2010s. The decadal changes in 10-m wind speeds were largely explained by the position of the jet stream and storm tracks and the strength of the north-south pressure gradient over the North Atlantic. In addition, we investigated the correlation between the North Atlantic Oscillation (NAO) and the Atlantic Multi-decadal Oscillation (AMO) in the three locations. The NAO has a positive correlation in the central North Atlantic and Finland and a negative correlation in Iberian Peninsula. The AMO correlates moderately with the winds in the central North Atlantic but no correlation was found in Finland or the Iberian Peninsula. Overall, our study highlights that rather than just using long-term linear trends in wind speeds it is more informative to consider inter-annual or decadal variability.</p>

A connected history of political economy in Asia and Europe, ca 1750–1914

2020 ◽  
pp. 1-2
Author(s):  
Alessandro Stanziani
Keyword(s):  
Political Economy ◽  
Ottoman Empire ◽  
North Atlantic ◽  
Western Europe ◽  
Economic Thought ◽  
The North ◽  
History Of ◽  
The North Atlantic ◽  
History Of Political Economy ◽  
Political Economic

The history of political-economic thought has been built up over the centuries with a uniform focus on European and North American thinkers. Intellectuals beyond the North Atlantic have been largely understood as the passive recipients of already formed economic categories and arguments. This view has often been accepted not only by scholars and observers in Europe but also in many other places such as Russia, India, China, Japan, and the Ottoman Empire. In this regard, the articles included in this collection explicitly differentiate from this diffusionist approach (“born in Western Europe, then flowed everywhere else”).

The ability of the adjoint technique to recover decadal variability of the North Atlantic circulation

2013 ◽  
Vol 69 ◽  
pp. 166-180 ◽  
Author(s):  
Michael Brüdgam ◽  
Carsten Eden ◽  
Lars Czeschel ◽  
Johanna Baehr
Keyword(s):  
North Atlantic ◽  
Decadal Variability ◽  
The North ◽  
The North Atlantic

scholarly journals Reconciling two alternative mechanisms behind bi-decadal variability in the North Atlantic

2015 ◽  
Vol 137 ◽  
pp. 237-249 ◽  
Author(s):  
Pablo Ortega ◽  
Juliette Mignot ◽  
Didier Swingedouw ◽  
Florian Sévellec ◽  
Eric Guilyardi
Keyword(s):  
North Atlantic ◽  
Decadal Variability ◽  
The North ◽  
The North Atlantic

Allied High Commission for Germany

1951 ◽  
Vol 5 (1) ◽  
pp. 226-227
Keyword(s):  
New York ◽  
North Atlantic ◽  
Western Europe ◽  
The North ◽  
Emergency Power ◽  
Western Germany ◽  
The North Atlantic ◽  
The Creation ◽  
Industrial Economic

During October and November, 1950, press reports indicated that the Allied High Commission for Germany was primarily concerned with the implementation of the three-power agreement on Germany reached in New York on September 19, 1950. Although all of the proposals relating to the creation of mobile police formations and the integration of German forces into those of western Europe were stalled pending agreement between the members of the North Atlantic Council as to the nature and size of such German forces, reports indicated that consideration of various proposals to amend the occupation statute were going forward. While no details were revealed, the Chancellor of western Germany (Adenauer) indicated that one suggestion had been that the easing of allied industrial, economic and political controls would be conditioned upon the acceptance by the Bonn government of prewar German debts and a willingness to share strategic war materials. Other reports indicated that the amended occupation statute would terminate controls over German use of funds, food and other supplies, permit the lapsing of powers enforcing decartelization once existing orders had been carried through and adequate legislation enacted, and would abandon the review of all laws or directives while reserving emergency power to annul any believed inconsistent with previous policy.

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