scholarly journals 20-Year Climatology ofNO3  −andNH4  +Wet Deposition at Ny-Ålesund, Svalbard

2011 ◽  
Vol 2011 ◽  
pp. 1-10 ◽  
Author(s):  
Rafael Kühnel ◽  
Tjarda J. Roberts ◽  
Mats P. Björkman ◽  
Elisabeth Isaksson ◽  
Wenche Aas ◽  
...  
Keyword(s):  
North Atlantic ◽  
Wet Deposition ◽  
Nitrogen Emissions ◽  
Solid Precipitation ◽  
The North ◽  
Annual Total ◽  
Nitrate Deposition ◽  
Rapid Transport ◽  
Precipitation Season ◽  
Reactive Nitrogen Emissions

A 20-year dataset of weekly precipitation observations in Ny-Ålesund, Svalbard, was analysed to assess atmospheric wet deposition of nitrogen. Mean annual total nitrogen deposition was 74 mg N/(m2 yr) but exhibited large interannual variability and was dominated by highly episodic “strong” events, probably caused by rapid transport from European sources. The majority (90%) of precipitation samples were defined as “weak” (<2 mg N/m2) and contributed an annual baseline of ~17 mg N/(m2 yr), whereas 10% of precipitation samples were defined as “strong” (>2 mg N/m2) and additionally contributed up to 225 mg N/(m2 yr). Nitrate deposition largely occurred in samples within the solid-precipitation season (16 September–2 June), and ammonium deposition occurred equally in both solid and liquid seasons. Trends of reactive nitrogen emissions from Europe are uncertain, and increasing cyclonic activity over the North Atlantic caused by a changing climate might lead to more strong deposition events in Svalbard.

scholarly journals Lagrangian analysis of low level anthropogenic plume processing across the North Atlantic

2008 ◽  
Vol 8 (2) ◽  
pp. 7509-7554
Author(s):  
E. Real ◽  
K. Law ◽  
H. Schlager ◽  
A. Roiger ◽  
H. Huntrieser ◽  
...  
Keyword(s):  
New York ◽  
North Atlantic ◽  
West Coast ◽  
Wet Deposition ◽  
Lagrangian Analysis ◽  
The North ◽  
Lagrangian Framework ◽  
Chemical Destruction ◽  
Research Aircraft ◽  
The North Atlantic

Abstract. The photochemical evolution of an anthropogenic plume from the New-York/Boston region during its transport at low altitudes over the North Atlantic to the European west coast has been studied using a Lagrangian framework. This plume, originally strongly polluted, was sampled by research aircraft just off the North American east coast on 3 successive days, and 3 days downwind off the west coast of Ireland where another aircraft re-sampled a weakly polluted plume. Changes in trace gas concentrations during transport were reproduced using a photochemical trajectory model including deposition and mixing effects. Chemical and wet deposition processing dominated the evolution of all pollutants in the plume. The mean net O3 production was evaluated to be -5 ppbv/day leading to low values of O3 by the time the plume reached Europe. Wet deposition of nitric acid was responsible for an 80% reduction in this O3 production. If the plume had not encountered precipitation, it would have reached the Europe with O3 levels up to 80-90 ppbv, and CO levels between 120 and 140 ppbv. Photochemical destruction also played a more important role than mixing in the evolution of plume CO due to high levels of both O3 and water vapour showing that CO cannot always be used as a tracer for polluted air masses, especially for plumes transported at low altitudes. The results also show that, in this case, an important increase in the O3/CO slope can be attributed to chemical destruction of CO and not to photochemical O3 production as is often assumed.

scholarly journals Increasing importance of deposition of reduced nitrogen in the United States

2016 ◽  
Vol 113 (21) ◽  
pp. 5874-5879 ◽  
Author(s):  
Yi Li ◽  
Bret A. Schichtel ◽  
John T. Walker ◽  
Donna B. Schwede ◽  
Xi Chen ◽  
...  
Keyword(s):  
United States ◽  
Nitrogen Deposition ◽  
Wet Deposition ◽  
Inorganic Nitrogen ◽  
Rapid Development ◽  
The United States ◽  
Natural Ecosystems ◽  
Nitrogen Emissions ◽  
Reduced Nitrogen ◽  
Reactive Nitrogen Emissions

Rapid development of agriculture and fossil fuel combustion greatly increased US reactive nitrogen emissions to the atmosphere in the second half of the 20th century, resulting in excess nitrogen deposition to natural ecosystems. Recent efforts to lower nitrogen oxides emissions have substantially decreased nitrate wet deposition. Levels of wet ammonium deposition, by contrast, have increased in many regions. Together these changes have altered the balance between oxidized and reduced nitrogen deposition. Across most of the United States, wet deposition has transitioned from being nitrate-dominated in the 1980s to ammonium-dominated in recent years. Ammonia has historically not been routinely measured because there are no specific regulatory requirements for its measurement. Recent expansion in ammonia observations, however, along with ongoing measurements of nitric acid and fine particle ammonium and nitrate, permit new insight into the balance of oxidized and reduced nitrogen in the total (wet + dry) US nitrogen deposition budget. Observations from 37 sites reveal that reduced nitrogen contributes, on average, ∼65% of the total inorganic nitrogen deposition budget. Dry deposition of ammonia plays an especially key role in nitrogen deposition, contributing from 19% to 65% in different regions. Future progress toward reducing US nitrogen deposition will be increasingly difficult without a reduction in ammonia emissions.

scholarly journals Natural forcing of the North Atlantic nitrogen cycle in the Anthropocene

2018 ◽  
Vol 115 (42) ◽  
pp. 10606-10611 ◽  
Author(s):  
Xingchen Tony Wang ◽  
Anne L. Cohen ◽  
Victoria Luu ◽  
Haojia Ren ◽  
Zhan Su ◽  
...  
Keyword(s):  
Nitrogen Cycle ◽  
North Atlantic ◽  
Formation Rate ◽  
Western Pacific ◽  
Mode Water ◽  
Nitrogen Emissions ◽  
Model Simulations ◽  
The North ◽  
Anthropogenic Nitrogen ◽  
The North Atlantic

Human alteration of the global nitrogen cycle intensified over the 1900s. Model simulations suggest that large swaths of the open ocean, including the North Atlantic and the western Pacific, have already been affected by anthropogenic nitrogen through atmospheric transport and deposition. Here we report an ∼130-year-long record of the15N/14N of skeleton-bound organic matter in a coral from the outer reef of Bermuda, which provides a test of the hypothesis that anthropogenic atmospheric nitrogen has significantly augmented the nitrogen supply to the open North Atlantic surface ocean. The Bermuda15N/14N record does not show a long-term decline in the Anthropocene of the amplitude predicted by model simulations or observed in a western Pacific coral15N/14N record. Rather, the decadal variations in the Bermuda15N/14N record appear to be driven by the North Atlantic Oscillation, most likely through changes in the formation rate of Subtropical Mode Water. Given that anthropogenic nitrogen emissions have been decreasing in North America since the 1990s, this study suggests that in the coming decades, the open North Atlantic will remain minimally affected by anthropogenic nitrogen deposition.

scholarly journals Lagrangian analysis of low altitude anthropogenic plume processing across the North Atlantic

2008 ◽  
Vol 8 (24) ◽  
pp. 7737-7754 ◽  
Author(s):  
E. Real ◽  
K. S. Law ◽  
H. Schlager ◽  
A. Roiger ◽  
H. Huntrieser ◽  
...  
Keyword(s):  
New York ◽  
North Atlantic ◽  
West Coast ◽  
Wet Deposition ◽  
Lagrangian Analysis ◽  
Air Masses ◽  
The North ◽  
Lagrangian Framework ◽  
Research Aircraft ◽  
The North Atlantic

Abstract. The photochemical evolution of an anthropogenic plume from the New-York/Boston region during its transport at low altitudes over the North Atlantic to the European west coast has been studied using a Lagrangian framework. This plume, originally strongly polluted, was sampled by research aircraft just off the North American east coast on 3 successive days, and then 3 days downwind off the west coast of Ireland where another aircraft re-sampled a weakly polluted plume. Changes in trace gas concentrations during transport are reproduced using a photochemical trajectory model including deposition and mixing effects. Chemical and wet deposition processing dominated the evolution of all pollutants in the plume. The mean net photochemical O3 production is estimated to be −5 ppbv/day leading to low O3 by the time the plume reached Europe. Model runs with no wet deposition of HNO3 predicted much lower average net destruction of −1 ppbv/day O3, arising from increased levels of NOx via photolysis of HNO3. This indicates that wet deposition of HNO3 is indirectly responsible for 80% of the net destruction of ozone during plume transport. If the plume had not encountered precipitation, it would have reached Europe with O3 concentrations of up to 80 to 90 ppbv and CO between 120 and 140 ppbv. Photochemical destruction also played a more important role than mixing in the evolution of plume CO due to high levels of O3 and water vapour showing that CO cannot always be used as a tracer for polluted air masses, especially in plumes transported at low altitudes. The results also show that, in this case, an increase in O3/CO slopes can be attributed to photochemical destruction of CO and not to photochemical O3 production as is often assumed.

The Currents of the North Atlantic

1892 ◽  
Vol 34 (872supp) ◽  
pp. 13940-13941
Author(s):  
Richard Beynon
Keyword(s):  
North Atlantic ◽  
The North ◽  
The North Atlantic

NATO adaptation to current challenges and mechanisms of Ukraine’s cooperation with the North Atlantic Treaty Organization

2019 ◽  
pp. 73-81
Author(s):  
Oleh Poshedin
Keyword(s):  
North Atlantic ◽  
Task Force ◽  
Response Force ◽  
Cyber Attack ◽  
Adaptation Measures ◽  
Joint Force ◽  
Security Environment ◽  
The North ◽  
The North Atlantic ◽  
Area Of Influence

The purpose of the article is to describe the changes NATO undergoing in response to the challenges of our time. Today NATO, as a key element of European and Euro-Atlantic security, is adapting to changes in the modern security environment by increasing its readiness and ability to respond to any threat. Adaptation measures include the components required to ensure that the Alliance can fully address the security challenges it might face. Responsiveness NATO Response Force enhanced by developing force packages that are able to move rapidly and respond to potential challenges and threats. As part of it, was established a Very High Readiness Joint Task Force, a new Allied joint force that deploy within a few days to respond to challenges that arise, particularly at the periphery of NATO’s territory. NATO emphasizes, that cyber defence is part of NATO’s core task of collective defence. A decision as to when a cyber attack would lead to the invocation of Article 5 would be taken by the North Atlantic Council on a case-by-case basis. Cooperation with NATO already contributes to the implementation of national security and defense in state policy. At the same time, taking into account that all decision-making in NATO based on consensus, Ukraine’s membership in the Alliance quite vague perspective. In such circumstances, in Ukraine you often can hear the idea of announcement of a neutral status. It is worth reminding that non-aligned status did not save Ukraine from Russian aggression. Neutral status will not accomplish it either. All talks about neutrality and the impossibility of Ukraine joining NATO are nothing but manipulations, as well as recognition of the Ukrainian territory as Russian Federation area of influence (this country seeks to sabotage the Euro-Atlantic movement of Ukraine). Think about it, Moldova’s Neutrality is enshrined in the country’s Constitution since 1994. However, this did not help Moldova to restore its territorial integrity and to force Russia to withdraw its troops and armaments from Transnistria.

Analysis of the ways of improvement of Ukraine – NATO cooperation on cybersecurity issues

2020 ◽  
Vol 10 (2) ◽  
pp. 11-15
Author(s):  
Volodymyr Shypovskyi ◽  
Volodymyr Cherneha ◽  
Serhiy Marchenkov
Keyword(s):  
Political Parties ◽  
North Atlantic ◽  
Lessons Learned ◽  
Cyber Warfare ◽  
The North ◽  
Collective Defense ◽  
Cyber Space ◽  
The Russian Federation ◽  
Modern Warfare ◽  
E Mail

Recent events in Ukraine have shown that, along with the advancement of information technology, methods of conducting modern warfare are being enhanced. Cyberspace is deliberately used by the Russian Federation to commit cyber warfare against Ukraine. Therefore, in order to address their influence effectively, it is important not only successfully deal with its consequences but also to foresee the potential adversaryʼs actions by analyzing their previous operations and incorporating the lessons learned by other countries. Across the globe, including Ukraine, the issue of information security and cyberattacks has become exceedingly urgent. Everybody is aware of the ongoing attacks on information networks of various government agencies and energy firms, cyberattacks on e-mail networks of political parties and organizations around the world. Likewise, despite the steadily growing numbers, cyberattack cases against the individuals and private businesses are not reported as widely as they occur. As a result, The North Atlantic Alliance countries began tackling the issue of cyberthreats much earlier than Ukraine. Consequently, NATO and its allies rely on powerful and robust cyber defenses to ensure the Alliance's core tasks of collective defense. The article discusses methods and strategies for providing cyber defense in NATO member states and recommends ways to increase the level of protection in the state's cyber space, as part of Ukraineʼs national security and defense domain.

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