scholarly journals The North American Lightning Detection Network (NALDN)—Analysis of Flash Data: 2001–09

2011 ◽  
Vol 139 (5) ◽  
pp. 1305-1322 ◽  
Author(s):  
Richard E. Orville ◽  
Gary R. Huffines ◽  
William R. Burrows ◽  
Kenneth L. Cummins
Keyword(s):  
United States ◽  
North America ◽  
North American ◽  
The United States ◽  
The North ◽  
Lightning Detection ◽  
Geographical Regions ◽  
Positive Peak ◽  
The U.S ◽  
Cg Lightning

Cloud-to-ground (CG) lightning data have been analyzed for the years 2001–09 for North America, which includes Alaska, Canada, and the lower 48 U.S. states. Flashes recorded within the North American Lightning Detection Network (NALDN) are examined. No corrections for detection efficiency variability are made over the 9 yr of the dataset or over the large geographical area comprising North America. There were network changes in the NALDN during the 9 yr, but these changes have not been corrected for nor have the recorded data been altered in any way with the exception that all positive lightning reports with peak currents less than 15 kA have been deleted. Thus, the reader should be aware that secular changes are not just climatological in nature. All data were analyzed with a spatial resolution of 20 km. The analyses presented in this work provide a synoptic view of the interannual variability of lightning observations in North America, including the impacts of physical changes in the network during the 9 yr of study. These data complement and extend previous analyses that evaluate the U.S. NLDN during periods of upgrade. The total (negative and positive) flashes for ground flash density, the percentage of positive lightning, and the positive flash density have been analyzed. Furthermore, the negative and positive first stroke peak currents and the flash multiplicity have been examined. The highest flash densities in Canada are along the U.S.–Canadian border (1–2 flashes per square kilometer) and in the United States along the Gulf of Mexico coast from Texas through Florida (exceeding 14 flashes per square kilometer in Florida). The Gulf Stream is “outlined” by higher flash densities off the east coast of the United States. Maximum annual positive flash densities in Canada range primarily from 0.01 to 0.3 flashes per square kilometer, and in the United States to over 0.5 flashes per square kilometer in the Midwest and in the states of Louisiana and Mississippi. The annual percentage of positive lightning to ground varies from less than 2% over Florida to values exceeding 25% off the West Coast, Alaska, and the Yukon. A localized maximum in the percentage of positive lightning in the NALDN occurs in Manitoba and western Ontario, just north of North Dakota and Minnesota. When averaged over North America, first stroke negative median peak currents range from 19.8 kA in 2001 to 16.0 kA in 2009 and for all years, average 16.1 kA. First stroke positive median peak currents range from a high of 29.0 kA in 2008 and 2009 to a low of 23.3 kA in 2003 with a median of 25.7 kA for all years. There is a relatively sharp transition from low to high median negative peak currents along the Gulf and Atlantic coasts of the United States. No sharp transitions are observed for the median positive peak currents. Relatively lower positive peak currents occur throughout the southeastern United States. The highest values of mean negative multiplicity exceed 3.0 strokes per flash in the NALDN with some variation over the 9 yr. Lower values of mean negative multiplicity occur in the western United States. Positive flash mean multiplicity is slightly higher than 1.1, with the highest values of 1.7 observed in the southwestern states. As has been noted in prior research, CG lightning has significant variations from storm to storm as well as between geographical regions and/or seasons and, consequently, a single distribution for any lightning parameter, such as multiplicity or peak current, may not be sufficient to represent or describe the parameter.

Neoliberalism and Counterinsurgency

Colombia ◽  
2020 ◽  
Author(s):  
Richard D. Mahoney
Keyword(s):  
United States ◽  
Free Trade ◽  
Latin American ◽  
North American ◽  
Free Trade Agreement ◽  
Trade Agreement ◽  
The United States ◽  
The North ◽  
Trade Promotion ◽  
The U.S

How did the U.S.-Colombia free trade agreement come about? The officially named “U.S.-Colombia Trade Promotion Agreement” was the stepchild of a rancorous hemispheric divorce between the United States and five Latin American governments over the proposal to extend the North American Free Trade Agreement...

Introduction

2020 ◽  
pp. 1-22
Author(s):  
Frank Towers
Keyword(s):  
United States ◽  
Nineteenth Century ◽  
North America ◽  
North American ◽  
The United States ◽  
Political Order ◽  
Nation State ◽  
History Of ◽  
Key Terms ◽  
The U.S

Today’s political map of North America took its basic shape in a continental crisis in the 1860s, marked by Canadian Confederation (1867), the end of the U.S. Civil War (1865), the restoration of the Mexican Republic (1867), and numerous wars and treaty regimes conducted between these states and indigenous peoples through the 1870s. This volume explores the tumultuous history of North American state-making in the mid-nineteenth century from a continental perspective that seeks to look across and beyond the traditional nation-centered approach. This introduction orients readers by first exploring the meaning of key terms—in particular sovereignty and its historical attachment to the concept of the nation state—and then previewing how contributors interrogate different themes of the mid-century struggles that remade the continent’s political order. Those themes fall into three main categories: the character of the states made and remade in the mid-1800s; the question of sovereignty for indigenous polities that confronted the European-settler descended governments of Canada, Mexico, and the United States; and the interaction between capitalist expansion and North American politics, and the concomitant implications of state making for sovereignty’s more diffuse meaning at the level of individual and group autonomy.

scholarly journals THE EFFECT OF THE GLACIAL EPOCH UPON THE DISTRIBUTION OF INSECTS IN NORTH AMERICA

1875 ◽  
Vol 7 (9) ◽  
pp. 164-167
Author(s):  
Aug. R. Grote
Keyword(s):  
United States ◽  
North America ◽  
North American ◽  
The United States ◽  
American Continent ◽  
North American Continent ◽  
The North ◽  
Glacial Epoch

From the condition of an hypothesis the glacial epoch has been elevated into that of a theory by the explanations it has afforded to a certain class of geological phenomena. The present paper endeavors to show that certain zoological facts are consistent with the presence, during past times, of a vast progressive field of ice, which, in its movement from north to south, gradually extended over large portions of the North American continent. These facts, in the present instance, are furnished by a study of our Lepidoptera, or certain kinds of butterflies and moths now inhabiting the United States and adjacent territories.

scholarly journals North American Free Trade Agreement

Politeja ◽  
2021 ◽  
Vol 18 (5(74)) ◽  
pp. 293-313
Author(s):  
Łukasz Wordliczek
Keyword(s):  
United States ◽  
Free Trade ◽  
North American ◽  
Free Trade Agreement ◽  
National Interest ◽  
Trade Agreement ◽  
The United States ◽  
Economic Relations ◽  
The North ◽  
The U.S

The article deals with the relationship between the United States and Mexico from the perspective of the US national security. The key areas of strategic interest in Mexico on the part of the United States include: limiting illegal immigration, fighting drug-related crime, economic cooperation, both bilateral and in the wider international dimension, for example the North American Free Trade Agreement. According to the United States, all three factors and their successful implementation are necessary and constituent elements of the national interest of the United States in its most important scope, that is, in increasing the security of the state. The analysis focuses on the U.S. economic relations with Mexico at the turn of the 20th and 21st centuries. The basis of economic relations between these countries is the North American Free Trade Agreement. The genesis of the NAFTA agreement and its effects on mutual relations in the context of the U.S. national interest and security was presented. Additionally, the reasons for President Donald Trump’s change from NAFTA to USMCA are described, from the perspective of U.S. strategic interests.

Graphical Analysis of Trans-Canada Airlines' Progress on the North American Routes 1946–1950

1952 ◽  
Vol 56 (497) ◽  
pp. 382-391
Author(s):  
Adam Jaworski
Keyword(s):  
United States ◽  
Quality Of Service ◽  
North American ◽  
The United States ◽  
Graphical Analysis ◽  
Total Revenue ◽  
Price Changes ◽  
The North ◽  
The U.S

Progress of any organisation may be related either to an assumed basis within the organisation itself, or to some other organisations, preferably competitors in the same business. The second method is more realistic and by relating the corresponding data in ratios, it helps to eliminate to a great extent the influence of price changes, which distort yearly comparisons of revenues and expenses.In the United States the trunk lines represent over 95 per cent. of the total revenue ton-miles flown on the domestic routes and in international aviation, the largest system with the highest quality of service. Therefore, by comparing in Part I the domestic services of Trans-Canada Air Lines (T.C.A.) to corresponding services of the U.S. trunk lines, the most severe criterion was chosen.Part II contains an investigation of trends of particular expenses in relation to the total expenses for T.C.A's North American Services.

scholarly journals CURRENT STATE AND PROSPECTS FOR THE DEVELOPMENT OF THE NORTH AMERICAN FREE TRADE AREA

2020 ◽  
pp. 74-84
Author(s):  
S. Yakubovskiy ◽  
T. Rodionova ◽  
O. Tsviakh
Keyword(s):  
United States ◽  
Interest Rates ◽  
Free Trade ◽  
North American ◽  
Free Trade Area ◽  
The United States ◽  
Investment Activity ◽  
Trade Area ◽  
The North ◽  
The U.S

This research aims to analyze current economic state of the North American Free Trade Area and to identify possible prospects for its development. The article explores the prerequisites for the formation of NAFTA, reasons for revising the agreement and compares the differences between the previous and updated agreements, an impact of integration association on the socio-economic status, trade and investment activity of the participating countries, prospects for its development and analysis of its economic cooperation with Ukraine. The empirical analysis shows a significant relationship between the U.S. GDP and foreign trade with Mexico and Canada, unemployment and interest rates. Its results revealed that the U.S. trade with Canada had a positive impact on the U.S. GDP; at the same time the U.S. trade with Mexico had a negative impact on the U.S. GDP, which became the main argument for President Trump in his pressure on Mexico to revise the terms of the NAFTA agreement. The regression analysis also showed that there is an inverse relationship between GDP and interest rate in the United States from 1994 to 2018. It was determined that the United States-Mexico-Canada Agreement (USMCA) is not fundamentally different from the previous one, but it can create new opportunities, for example, for workers and farmers in the United States, and new difficulties for Canada and Mexico. This agreement tightens labor standards and protection of intellectual property rights, especially in Mexico, thus, probably decreasing the attractiveness of Mexican economy to foreign investors, that is likely to reduce the U.S. investment in Mexico. Thus, Canada and Mexico are expected to receive less benefit from the USMCA for their economies than the United States.

scholarly journals Progress in Diagnosing Primary Ciliary Dyskinesia: The North American Perspective

Diagnostics ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1278
Author(s):  
Michael Glenn O’Connor ◽  
Amjad Horani ◽  
Adam J. Shapiro
Keyword(s):  
Genetic Testing ◽  
North America ◽  
North American ◽  
Primary Ciliary Dyskinesia ◽  
Clinical Phenotype ◽  
The United States ◽  
Diagnostic Process ◽  
The North ◽  
Diagnostic Guideline ◽  
Ciliary Dyskinesia

Primary Ciliary Dyskinesia (PCD) is a rare, under-recognized disease that affects respiratory ciliary function, resulting in chronic oto-sino-pulmonary disease. The PCD clinical phenotype overlaps with other common respiratory conditions and no single diagnostic test detects all forms of PCD. In 2018, PCD experts collaborated with the American Thoracic Society (ATS) to create a clinical diagnostic guideline for patients across North America, specifically considering the local resources and limitations for PCD diagnosis in the United States and Canada. Nasal nitric oxide (nNO) testing is recommended for first-line testing in patients ≥5 years old with a compatible clinical phenotype; however, all low nNO values require confirmation with genetic testing or ciliary electron micrograph (EM) analysis. Furthermore, these guidelines recognize that not all North American patients have access to nNO testing and isolated genetic testing is appropriate in cases with strong clinical PCD phenotypes. For unresolved diagnostic cases, referral to a PCD Foundation accredited center is recommended. The purpose of this narrative review is to provide insight on the North American PCD diagnostic process, to enhance the understanding of and adherence to current guidelines, and to promote collaboration with diagnostic pathways used outside of North America.

scholarly journals “The Future of Archaeology Is Antiracist”: Archaeology in the Time of Black Lives Matter

2021 ◽  
pp. 1-20
Author(s):  
Ayana Omilade Flewellen ◽  
Justin P. Dunnavant ◽  
Alicia Odewale ◽  
Alexandra Jones ◽  
Tsione Wolde-Michael ◽  
...  
Keyword(s):  
United States ◽  
North American ◽  
The United States ◽  
Heritage Preservation ◽  
Social Unrest ◽  
Black Lives Matter ◽  
The North ◽  
Road Map ◽  
The Social ◽  
The Future

This forum builds on the discussion stimulated during an online salon in which the authors participated on June 25, 2020, entitled “Archaeology in the Time of Black Lives Matter,” and which was cosponsored by the Society of Black Archaeologists (SBA), the North American Theoretical Archaeology Group (TAG), and the Columbia Center for Archaeology. The online salon reflected on the social unrest that gripped the United States in the spring of 2020, gauged the history and conditions leading up to it, and considered its rippling throughout the disciplines of archaeology and heritage preservation. Within the forum, the authors go beyond reporting the generative conversation that took place in June by presenting a road map for an antiracist archaeology in which antiblackness is dismantled.

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