The north american vertical datum of 1988 (navd ‘88) internal status report prepared for cism ‘88 winnipeg, manitoba may 24-27, 1988

CISM journal ◽  
1989 ◽  
Vol 43 (4) ◽  
pp. 387-393
Author(s):  
Fred W. Young ◽  
John Murakami
Keyword(s):  
North American ◽  
The United States ◽  
Geodetic Survey ◽  
Background Information ◽  
Status Report ◽  
National Geodetic Survey ◽  
The North ◽  
Vertical Datum ◽  
History Of ◽  
Expected Benefits

Canada and the United States through their respective national geodetic survey organizations have been cooperating in a project to redefine the heights for bench marks in North America. This report will deal with a history of the levelling network in Canada, provide background information about the North American Vertical Datum of 1988 (NAVD ‘88) Project itself, give an update concerning key Canadian activities and tasks related to the project, and finally state the expected benefits of such an undertaking.

scholarly journals REPLACING NAVD88: THE EFFECTS OF VERTICAL DATUM MODERNIZATION ON COASTAL ENGINEERING

2018 ◽  
pp. 58
Author(s):  
Nicole Kinsman ◽  
Monica Youngman
Keyword(s):  
Mississippi River ◽  
North American ◽  
Vertical Motion ◽  
The United States ◽  
Satellite System ◽  
Geodetic Survey ◽  
National Geodetic Survey ◽  
Geoid Model ◽  
The North ◽  
Vertical Datum

The United States (US) National Geodetic Survey (NGS) will be replacing the North American Vertical Datum of 1988 (NAVD88) with the North American-Pacific Geopotential Datum of 2022 (NAPGD2022). NAVD88 is still the official vertical datum of the NSRS at this time, but it is in need of improvement; it is both biased (by about one-half meter) and tilted (about 1 meter coast to coast) relative to the best global geoid models available today. This issue stems from the fact that NAVD88 was defined primarily using terrestrial surveying techniques at passive geodetic survey marks. For access, users must often collect hours of Global Navigation Satellite System (GNSS) data, or rely on our nation’s network of passive survey marks, which is not fully stable (consider areas of subsidence such as the Mississippi River delta) and is deteriorating over time. Maintenance of these marks requires significant resources and vertical motion of marks is not tracked in a systematic way. A modernized vertical reference frame will primarily rely on GNSS such as the Global Positioning System (GPS) in combination with an updated and time-tracked geoid model. This paradigm shift will result in improvements to the National Spatial Reference System (NSRS) that will provide users with enhanced access, easier maintenance, and more consistent coordinates for precise positioning activities nationwide.

Modernizing the Datums of the National Spatial Reference System

2015 ◽  
Vol 49 (2) ◽  
pp. 151-158
Author(s):  
Dru A. Smith ◽  
Daniel R. Roman ◽  
Vicki A. Childers
Keyword(s):  
North American ◽  
Reference System ◽  
Passive Control ◽  
The United States ◽  
Geodetic Survey ◽  
Federal Agencies ◽  
National Geodetic Survey ◽  
Spatial Reference ◽  
The North ◽  
Vertical Datum

AbstractThe National Spatial Reference System (NSRS) is the official coordinate system for all geospatial activities performed by civilian federal agencies of the United States, including National Oceanic and Atmospheric Administration's navigational charts. Two of the datums that make up the bulk of the NSRS, the North American Datum of 1983 (NAD 83) and the North American Vertical Datum of 1988 (NAVD 88), were created with the most accurate surveying technology available in the 1970s and 1980s. However, analysis over the last decade has proven that both datums contain systematic errors at the few meters level. While there have been improvements to these datums over the years, they have all been restricted to adjusting subsets of coordinates within the datum, rather than replacing the datum itself. However, the rise of near-real-time positioning technologies at the few centimeter level has made it no longer viable to maintain the two datums.The National Geodetic Survey is engaged in a decade-long effort to prepare the NSRS user community and collect the necessary data to define two new datums that will not only replace NAD 83 and NAVD 88 but also reduce the overall reliance of those two datums on passive control. The two new datums are expected to be completed and jointly released in 2022.

The experimental geoid 2020 – the first joint geoid model for the North American and Pacific Geopotential Datum 

2021 ◽  
Author(s):  
Yan Ming Wang ◽  
Xiaopeng Li ◽  
Kevin Ahlgren ◽  
Jordan Krcmaric ◽  
Ryan Hardy ◽  
...  
Keyword(s):  
North American ◽  
Gravity Data ◽  
The United States ◽  
Geodetic Survey ◽  
Airborne Gravity ◽  
Data Sets ◽  
National Geodetic Survey ◽  
Geoid Model ◽  
Satellite Gravity ◽  
The North

<p>For the upcoming North American-Pacific Geopotential Datum of 2022, the National Geodetic Survey (NGS), the Canadian Geodetic Survey (CGS) and the National Institute of Statistics and Geography of Mexico (INEGI) computed the first joint experimental gravimetric geoid model (xGEOID) on 1’x1’ grids that covers a region bordered by latitude 0 to 85 degree, longitude 180 to 350 degree east. xGEOID20 models are computed using terrestrial gravity data, the latest satellite gravity model GOCO06S, altimetric gravity data DTU15, and an additional nine airborne gravity blocks of the GRAV-D project, for a total of 63 blocks. In addition, a digital elevation model in a 3” grid was produced by combining MERIT, TanDEM-X, and USGS-NED and used for the topographic/gravimetric reductions. The geoid models computed from the height anomalies (NGS) and from the Helmert-Stokes scheme (CGS) were combined using two different weighting schemes, then evaluated against the independent GPS/leveling data sets. The models perform in a very similar way, and the geoid comparisons with the most accurate Geoid Slope Validation Surveys (GSVS) from 2011, 2014 and 2017 indicate that the relative geoid accuracy could be around 1-2 cm baseline lengths up to 300 km for these GSVS lines in the United States. The xGEOID20 A/B models were selected from the combined models based on the validation results. The geoid accuracies were also estimated using the forward modeling.</p>

Epic Learning in an Indian Pueblo: A Framework for Studying Multigenerational Learning in the History of Education

2014 ◽  
Vol 54 (3) ◽  
pp. 286-302 ◽  
Author(s):  
Adrea Lawrence
Keyword(s):  
United States ◽  
American Indian ◽  
North American ◽  
Southern California ◽  
History Of Education ◽  
The United States ◽  
Indian Populations ◽  
The North ◽  
History Of ◽  
North American Indian

Writing from her position as the Office of Indian Affairs (OIA) Superintendent at the Potrero School on the Morongo (Malki) reservation in southern California in 1909, Clara D. True concluded an article on her experiences as an Anglo teacher working with American Indian populations in the United States: The more one knows of the Indian as he really is, not as he appears to the tourist, the teacher, or the preacher, the more one wonders. The remnant of knowledge that the Red Brother has is an inheritance from a people of higher thought than we have usually based our speculation upon. It is to be regretted that in dealing with the Indian we have not regarded him worthwhile until it is too late to enrich our literature and traditions with the contribution he could so easily have made. We have regarded him as a thing to be robbed and converted rather than as a being with intellect, sensibilities, and will, all highly developed, the development being one on different lines from our own as only necessity dictated. The continent was his college. The slothful student was expelled from it by President Nature. Physically, mentally, and morally, the North American Indian before the degradation at our hands was a man whom his descendants need not despise.

scholarly journals RUSSIA’S ROLE IN THE STRUGGLE FOR THE INDEPENDENCE OF THE NORTH AMERICAN COLONIES

2021 ◽  
Vol 2 (2) ◽  
pp. 5-12
Author(s):  
Vladislav L. Gorfin ◽  
Alexander M. Rybakov
Keyword(s):  
United States ◽  
Foreign Policy ◽  
Great Britain ◽  
North American ◽  
United States Of America ◽  
The United States ◽  
Xviii Century ◽  
American Colonies ◽  
The North ◽  
History Of

In the article the authors show the place of Russia in the struggle for the independence of the United States. They reveal the concept of «military neutrality», its essence and content. They define the basic principles of the world colonial system in the XVIII century, the foundations of interrelation between world powers and their colonies. They identify the priorities and interests for the development of foreign policy relations. They establish causal links between the war of the North American colonies of Great Britain for their independence and the policies of a number of European powers (Russia, Great Britain, France), as well as the consequences to which it led. The article considers the history of the struggle for independence and the formation of a new state of the United States of America, the development of foreign policy relations. The authors focus on the history of Russian-American relations in the second half of the XVIII century in the political aspect, and emphasize the increasing penetration of Russia’s influence in the scientific and cultural spheres which directly influenced and enriched the two countries. The relations between Russia and the United States and their history are studied. The history of relations between Russia and Great Britain is shown. The authors analyze the history of attempts to involve the Russian Empire in the war on the side of Great Britain, the position of the Russian government and Catherine II, as well as their attitude to these attempts. The authors give prominence to a number of world political figures and note their personal contribution to the process of struggle for independence and the further development of the United States of America. Unknown moments of their biographies are revealed. Conclusions are drawn about the role and the place of the leading countries of the period under study in the struggle for freedom and independence of the future superpower.

Synthesis of Results from the North American Monsoon Experiment (NAME) Process Study

2007 ◽  
Vol 20 (9) ◽  
pp. 1601-1607 ◽  
Author(s):  
Wayne Higgins ◽  
David Gochis
Keyword(s):  
United States ◽  
Central America ◽  
North American ◽  
The United States ◽  
Background Information ◽  
North American Monsoon ◽  
The North ◽  
Process Study ◽  
Monsoon System ◽  
United States Mexico

Abstract An international team of scientists from the United States, Mexico, and Central America carried out a major field campaign during the summer of 2004 to develop an improved understanding of the North American monsoon system leading to improved precipitation forecasts. Results from this campaign, which is the centerpiece of the North American Monsoon Experiment (NAME) Process Study, are reported in this issue of the Journal of Climate. In addition to a synthesis of key findings, this brief overview article also raises some important unresolved issues that require further attention. More detailed background information on NAME, including motivating science questions, where NAME 2004 was conducted, when, and the experimental design, was published previously by Higgins et al.

scholarly journals On-Premise Signs and the North American Suburban Enclosed Shopping Mall

2018 ◽  
Vol 2 (2) ◽  
pp. 41-50
Author(s):  
Dawn Jourdan ◽  
Craig Berger
Keyword(s):  
United States ◽  
North American ◽  
Economic Change ◽  
The United States ◽  
Shopping Mall ◽  
Design And Development ◽  
Modular Systems ◽  
The North ◽  
History Of

The first fully enclosed modern suburban shopping mall, Southdale Center, opened in 1956 and immediately established a standard for how retailers and signs were to operate within their confines. Enclosed Malls were one of the first unique building types designed for suburban automotive environments and have been the retail economic drive in the United States for seventy years. They established a variety of sign innovations over the years, from developing strict sign guidelines, to creating formal zones with shared modular systems. This report summary will explore the sign advances that marked each of the five stages of mall evolution as well as how the current changes with a new retail revolution is impacting design and development. The report will also show how precedents established early in the history of mall development has been continually reinvented with economic change and design trends.

scholarly journals On-Premise Signs and the North American Suburban Enclosed Shopping Mall

2018 ◽  
Vol 2 (2) ◽  
pp. 41-50
Author(s):  
Craig Berger
Keyword(s):  
United States ◽  
North American ◽  
The United States ◽  
Shopping Mall ◽  
Design And Development ◽  
Economic Changes ◽  
Modular Systems ◽  
The North ◽  
History Of

The first fully enclosed modern suburban shopping mall, Southdale Center, opened in 1956 and immediately established a standard for how retailers and signs were to operate within their confines. Enclosed Malls were one of the first unique building types designed for suburban automotive environments and have been a key retail economic driver in the United States for seventy years. The mall also reflected economic changes in the country and the increasing separation of income classes. Malls established a variety of sign innovations over the years, from developing strict sign guidelines, to creating formal zones with shared modular systems. This report will explore the sign advances that marked each of the five stages of mall evolution impacted design and development. The report will also show how precedents established early in the history of mall development as a center for a broad range of incomes changed as malls began to segment by class.

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