scholarly journals The impact of monthly variation of the Pacific–North America (PNA) teleconnection pattern on wintertime surface-layer aerosol concentrations in the United States

2016 ◽  
Vol 16 (8) ◽  
pp. 4927-4943 ◽  
Author(s):  
Jin Feng ◽  
Hong Liao ◽  
Jianping Li
Keyword(s):  
United States ◽  
Surface Layer ◽  
Air Quality ◽  
North America ◽  
Organic Carbon ◽  
Black Carbon ◽  
The United States ◽  
The Pacific ◽  
The Us ◽  
The Impact

Abstract. The Pacific–North America teleconnection (PNA) is the leading general circulation pattern in the troposphere over the region of North Pacific to North America during wintertime. This study examined the impacts of monthly variations of the PNA phase (positive or negative phase) on wintertime surface-layer aerosol concentrations in the United States (US) by analyzing observations during 1999–2013 from the Air Quality System of the Environmental Protection Agency (EPA-AQS) and the model results for 1986–2006 from the global three-dimensional Goddard Earth Observing System (GEOS) chemical transport model (GEOS-Chem). The composite analyses on the EPA-AQS observations over 1999–2013 showed that the average concentrations of PM2.5, sulfate, nitrate, ammonium, organic carbon, and black carbon aerosols over the US were higher in the PNA positive phases (25 % of the winter months examined, and this fraction of months had the highest positive PNA index values) than in the PNA negative phases (25 % of the winter months examined, and this fraction of months had the highest negative PNA index values) by 1.0 µg m−3 (8.7 %), 0.01 µg m−3 (0.5 %), 0.3 µg m−3 (29.1 %), 0.1 µg m−3 (11.9 %), 0.6 µg m−3 (13.5 %), and 0.2 µg m−3 (27.8 %), respectively. The simulated geographical patterns of the differences in concentrations of all aerosol species between the PNA positive and negative phases were similar to observations. Based on the GEOS-Chem simulation, the pattern correlation coefficients were calculated to show the impacts of PNA-induced variations in meteorological fields on aerosol concentrations. The PNA phase was found (i) to influence sulfate concentrations mainly through changes in planetary boundary layer height (PBLH), precipitation (PR), and temperature; (ii) to influence nitrate concentrations mainly through changes in temperature; and (iii) to influence concentrations of ammonium, organic carbon, and black carbon mainly through changes in PR and PBLH. Results from this work have important implications for the understanding and prediction of air quality in the US.

scholarly journals The impact of monthly variation of the Pacific-North America (PNA) teleconnection pattern on wintertime surface-layer aerosol concentrations in the United States

2015 ◽  
Vol 15 (22) ◽  
pp. 33209-33251
Author(s):  
J. Feng ◽  
H. Liao ◽  
J. Li
Keyword(s):  
United States ◽  
Surface Layer ◽  
Air Quality ◽  
North America ◽  
Organic Carbon ◽  
Black Carbon ◽  
The United States ◽  
Monthly Variation ◽  
The Pacific ◽  
The Us

Abstract. The Pacific-North America teleconnection (PNA) is the leading general circulation pattern in the troposphere over the region of North Pacific to North America during wintertime. This study examined the impacts of monthly variation of the PNA phase (positive or negative phase) on wintertime surface-layer aerosol concentrations in the US by analyzing observations during 1999–2013 from the Air Quality System of Environmental Protection Agency (EPA-AQS) and the model results for 1986–2006 from the global three-dimensional Goddard Earth Observing System (GEOS) chemical transport model (GEOS-Chem). The composite analyses on the EPA-AQS observations over 1999–2003 showed that the average concentrations of PM2.5, sulfate, nitrate, ammonium, organic carbon, and black carbon aerosols over the US were higher in the PNA positive phases than in the PNA negative phases by 1.4 μg m−3 (12.7 %), 0.1 μg m−3 (6.4 %), 0.3 μg m−3 (39.1 %), 0.2 μg m−3 (22.8 %), 0.8 μg m−3 (21.3 %), and 0.2 μg m−3 (34.1 %), respectively. The simulated geographical patterns of the differences in concentrations of all aerosol species between the PNA positive and negative phases were similar to observations. Based on the GEOS-Chem simulation driven by the assimilated meteorological fields, the PNA-induced variation in planetary boundary layer height was found to be the most dominant meteorological factor that influenced the concentrations of PM2.5, sulfate, ammonium, organic carbon, and black carbon, and the PNA-induced variation in temperature was the most important parameter that influenced nitrate aerosol. Results from this work have important implications for understanding and prediction of air quality in the United States.

Shaping Forces, Networks, and Local Influences

2017 ◽  
Author(s):  
Nancy Yunhwa Rao
Keyword(s):  
United States ◽  
North America ◽  
Historical Context ◽  
The United States ◽  
Chinese Opera ◽  
Nation States ◽  
The Pacific ◽  
Chinese Theater ◽  
The Many ◽  
The Impact

This chapter surveys the historical context of the 1920s renaissance of Chinese opera theaters in the United States, including social, economic, cultural, and political forces of nation-states that helped shape the Chinese theater network linking China, the United States, Canada, and Cuba. It represents an important shift of the discourse of American musical history from the traditional focus of Atlantic World to that of the Pacific, presenting Chinatown theaters of North America as products of complex transnational forces. It also considers the symbolic significance of language and the impact of transnational network. The chapter therefore challenges the traditional characterization of the Chinese theater community as recalcitrant, demonstrating the many ways in which Chinese and Chinese American performers, owners, and patrons were active participants in the cultural milieu of North America in this period.

scholarly journals The impact of marine organics on the air quality of the western United States

2010 ◽  
Vol 10 (3) ◽  
pp. 6257-6278 ◽  
Author(s):  
B. Gantt ◽  
N. Meskhidze ◽  
A. G. Carlton
Keyword(s):  
United States ◽  
Air Quality ◽  
Atmospheric Chemistry ◽  
Environmental Protection Agency ◽  
Regional Scale ◽  
The United States ◽  
Coastal Areas ◽  
Western United States ◽  
The Us ◽  
The Impact

Abstract. The impact of marine organic emissions to the air quality in coastal areas of the western United States is studied using the latest version of the US Environmental Protection Agency (EPA) regional-scale Community Multiscale Air Quality (CMAQv4.7) modeling system. Emissions of marine isoprene, monoterpenes, and primary organic matter (POM) from the ocean are implemented into the model to provide a comprehensive view of the connection between ocean biology and atmospheric chemistry and air pollution. Model simulations show that marine organics can increase the concentration of PM2.5 by 0.1–0.3 μg m−3 (up to 5%) in coastal cities. This increase in the PM2.5 concentration is primarily attributed to the POM emissions, with small contributions from the marine isoprene and monoterpenes. When marine organic emissions are included, organic carbon (OC) concentrations over the remote ocean are increased by up to 50% (25% in coastal areas), values consistent with recent observational findings. This study is the first to quantify the air quality impacts from marine POM and monoterpenes for the United States, and highlights the need for inclusion of marine organic emissions in air quality models.

scholarly journals The effects of global change upon United States air quality

2015 ◽  
Vol 15 (21) ◽  
pp. 12645-12665 ◽  
Author(s):  
R. Gonzalez-Abraham ◽  
S. H. Chung ◽  
J. Avise ◽  
B. Lamb ◽  
E. P. Salathé ◽  
...  
Keyword(s):  
United States ◽  
Land Use ◽  
Particulate Matter ◽  
Air Quality ◽  
The United States ◽  
Biogenic Emissions ◽  
Anthropogenic Emissions ◽  
The Us ◽  
The Impact ◽  
Global Emissions

Abstract. To understand more fully the effects of global changes on ambient concentrations of ozone and particulate matter with aerodynamic diameter smaller than 2.5 μm (PM2.5) in the United States (US), we conducted a comprehensive modeling effort to evaluate explicitly the effects of changes in climate, biogenic emissions, land use and global/regional anthropogenic emissions on ozone and PM2.5 concentrations and composition. Results from the ECHAM5 global climate model driven with the A1B emission scenario from the Intergovernmental Panel on Climate Change (IPCC) were downscaled using the Weather Research and Forecasting (WRF) model to provide regional meteorological fields. We developed air quality simulations using the Community Multiscale Air Quality Model (CMAQ) chemical transport model for two nested domains with 220 and 36 km horizontal grid cell resolution for a semi-hemispheric domain and a continental United States (US) domain, respectively. The semi-hemispheric domain was used to evaluate the impact of projected global emissions changes on US air quality. WRF meteorological fields were used to calculate current (2000s) and future (2050s) biogenic emissions using the Model of Emissions of Gases and Aerosols from Nature (MEGAN). For the semi-hemispheric domain CMAQ simulations, present-day global emissions inventories were used and projected to the 2050s based on the IPCC A1B scenario. Regional anthropogenic emissions were obtained from the US Environmental Protection Agency National Emission Inventory 2002 (EPA NEI2002) and projected to the future using the MARKet ALlocation (MARKAL) energy system model assuming a business as usual scenario that extends current decade emission regulations through 2050. Our results suggest that daily maximum 8 h average ozone (DM8O) concentrations will increase in a range between 2 to 12 parts per billion (ppb) across most of the continental US. The highest increase occurs in the South, Central and Midwest regions of the US due to increases in temperature, enhanced biogenic emissions and changes in land use. The model predicts an average increase of 1–6 ppb in DM8O due to projected increase in global emissions of ozone precursors. The effects of these factors are only partially offset by reductions in DM8O associated with decreasing US anthropogenic emissions. Increases in PM2.5 levels between 4 and 10 μg m−3 in the Northeast, Southeast, Midwest and South regions are mostly a result of increase in primary anthropogenic particulate matter (PM), enhanced biogenic emissions and land use changes. Changes in boundary conditions shift the composition but do not alter overall simulated PM2.5 mass concentrations.

Pentecostalism and African diaspora : a case study of the Redeemed Christian Church of God (RCCG), in North America

2020 ◽  
Vol 1 (2) ◽  
pp. 77-92
Author(s):  
Rotimi Williams Omotoye
Keyword(s):  
United States ◽  
North America ◽  
United States Of America ◽  
The United States ◽  
Church Of God ◽  
Sources Of Information ◽  
Christian Church ◽  
Secondary Sources ◽  
The Impact ◽  
The Church

Pentecostalism as a new wave of Christianity became more pronounced in 1970's and beyond in Nigeria. Since then scholars of Religion, History, Sociology and Political Science have shown keen interest in the study of the Churches known as Pentecostals because of the impact they have made on the society. The Redeemed Christian Church of God (RCCG) was established by Pastor Josiah Akindayomi in Lagos,Nigeria in 1952. After his demise, he was succeeded by Pastor Adeboye Adejare Enock. The problem of study of this research was an examination of the expansion of the Redeemed Christian Church of God to North America, Caribbean and Canada. The missionary activities of the church could be regarded as a reversed mission in the propagation of Christianity by Africans in the Diaspora. The methodology adopted was historical. The primary and secondary sources of information were also germane in the research. The findings of the research indicated that the Redeemed Christian Church of God was founded in North America by Immigrants from Nigeria. Pastor Adeboye Enock Adejare had much influence on the Church within and outside the country because of his charisma. The Church has become a place of refuge for many immigrants. They are also contributing to the economy of the United States of America. However, the members of the Church were faced with some challenges, such as security scrutiny by the security agencies. In conclusion, the RCCGNA was a denomination that had been accepted and embraced by Nigerians and African immigrants in the United States of America.

The Impact of Monetary and Fiscal Policies on the Stock Market in the United States (U.S); Evidence from Linear ARDL Framework

2020 ◽  
Vol 11 (1) ◽  
pp. 132-132
Author(s):  
Aref Emamian
Keyword(s):  
United States ◽  
Stock Market ◽  
The United States ◽  
Real Effective Exchange Rate ◽  
Annual Data ◽  
Fiscal Policies ◽  
Long Run ◽  
The Us ◽  
Short Run ◽  
The Impact

This study examines the impact of monetary and fiscal policies on the stock market in the United States (US), were used. By employing the method of Autoregressive Distributed Lags (ARDL) developed by Pesaran et al. (2001). Annual data from the Federal Reserve, World Bank, and International Monetary Fund, from 1986 to 2017 pertaining to the American economy, the results show that both policies play a significant role in the stock market. We find a significant positive effect of real Gross Domestic Product and the interest rate on the US stock market in the long run and significant negative relationship effect of Consumer Price Index (CPI) and broad money on the US stock market both in the short run and long run. On the other hand, this study only could support the significant positive impact of tax revenue and significant negative impact of real effective exchange rate on the US stock market in the short run while in the long run are insignificant. Keywords: ARDL, monetary policy, fiscal policy, stock market, United States

scholarly journals The Dimensions of the US-China Trade War

2020 ◽  
Vol 3 (1) ◽  
pp. 47-55
Author(s):  
Mohamad Zreik
Keyword(s):  
United States ◽  
Indian Ocean ◽  
Free Trade ◽  
The United States ◽  
Bilateral Agreements ◽  
China Trade ◽  
The Pacific ◽  
The Us ◽  
The Indian Ocean ◽  
Trade War

AbstractThe Chinese Ministry of Commerce issued a statement Friday morning, July 6, 2018, confirming the outbreak of a trade war between the United States and China. The statement came after the United States imposed tariffs on many Chinese goods, in violation of international and bilateral agreements, and the destruction of the concept of free trade which the United States calls for following it. It is a war of opposite directions, especially the contradiction between the new Trump policy and the Chinese approach. The proof is what US Defense Secretary James Matisse announced in Singapore in early June 2018 of “the full strategy of the new United States, in the Indian Ocean and the Pacific,” where China was the “sole enemy of the United States” in China’s geostrategic region. Intentions have become publicized, and trade war between the two economic giants is turning into a reality. This paper will give an overview of the US-China scenario of trade war, then a focused analysis on the Trump’s administration economic decision regarding China, and the consequences of this decision.

scholarly journals The Convergence of Military Conduct and Policing in Israeli-Controlled Territories

2020 ◽  
Vol 35 (2) ◽  
pp. 1-8
Author(s):  
Nir Gazit ◽  
Keyword(s):  
United States ◽  
Police Officer ◽  
The United States ◽  
Police Brutality ◽  
Media Attention ◽  
Military Forces ◽  
The Us ◽  
The Military ◽  
The Impact

The murder of George Floyd by a police officer in the United States in May 2020 and the subsequent turmoil, as well as the violence against migrants on the US-Mexican border, have drawn major public and media attention to the phenomenon of police brutality (see, e.g., Levin 2020; Misra 2018; Taub 2020), which is often labeled as ‘militarization of police’. At the same time, in recent years military forces have been increasingly involved in policing missions in civilian environments, both domestically (see, e.g., Kanno-Youngs 2020; Schrader 2020; Shinkman 2020) and abroad. The convergence of military conduct and policing raises intriguing questions regarding the impact of these tendencies on the military and the police, as well as on their legitimacy.

scholarly journals Quebec’s Economic and Commercial Linkages with the United States, 1994–2017

2017 ◽  
Author(s):  
Earl H. Fry
Keyword(s):  
United States ◽  
Trade Agreement ◽  
The United States ◽  
The North ◽  
Nation States ◽  
Wide Range ◽  
The Us ◽  
Us Government ◽  
Big Picture ◽  
The Impact

This article examines the ebb and flow of the Quebec government’s economic and commercial relations with the United States in the period 1994–2017. The topic demonstrates the impact of three major forces on Quebec’s economic and commercial ties with the US: (1) the North American Free Trade Agreement (NAFTA) which became operational in 1994 and was fully implemented over a 15-year period; (2) the onerous security policies put in place by the US government in the decade following the horrific events of 11 September 2001; and (3) changing economic circumstances in the United States ranging from robust growth to the worst recession since the Great Depression of the 1930s. The article also indicates that the Quebec government continues to sponsor a wide range of activities in the United States, often more elaborate and extensive than comparable activities pursued by many nation-states with representation in the US. 1 1 Stéphane Paquin, ‘Quebec-U.S. Relations: The Big Picture’, American Review of Canadian Studies 46, no. 2 (2016): 149–61.

scholarly journals Bicycling, Birding and #BLM across America in a Summer of Chaos

2020 ◽  
Vol 4 ◽  
Author(s):  
Scott Edwards
Keyword(s):  
United States ◽  
Social Media ◽  
National Level ◽  
Political Stability ◽  
The United States ◽  
Local Communities ◽  
Rural America ◽  
The Pacific ◽  
The Us ◽  
White Violence

From 6 June to 20 August, 2020, I undertook a 76-day, ~3800 mile bicycle trip across the United States from the Atlantic to the Pacific oceans. In this talk I will share with you some of the amazing people, landscapes and birds I encountered, mostly in rural towns and along blue highways. The gradually changing birdscape, both in sight and sound, underscored the sensitive ecological gradients to which birds respond, as well as the ability of some species to thrive in agricultural monocultures. Rivers large and small regularly benchmarked my progress, as well as the western journey of Lewis & Clark over 200 years ago. The recent incidents in the US involving African Americans as targets of white violence inexorably caused me to festoon my bicycle with #BlackLivesMatter (#BLM) signs and share my experiences on social media. I encountered a variety of reactions, often positive and occasionally sharply negative, in a sea of generosity and extraordinary kindness as I wheeled my way through towns on the brink of collapse, vast private ranches and the occasional city. Rural America exhibits an abundance of loyalty and empathy for local communities, yet it is sometimes hard for Americans – myself included – to empathize with people they have never met in person. Two imperatives I took away, with ramifications for both biodiversity and political stability, were the need to somehow bring divergent communities together and to encourage empathy at the national level, among communities that otherwise experience each other only on TV.

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