AN EVALUATION OF THE GRAVITY CONTROL NETWORK IN NORTH AMERICA

Geophysics ◽  
1961 ◽  
Vol 26 (1) ◽  
pp. 57-76 ◽  
Author(s):  
J. C. Behrendt ◽  
G. P. Woollard
Keyword(s):  
North America ◽  
Geodetic Survey ◽  
Control Network ◽  
Mean Values ◽  
The North ◽  
University Of Wisconsin ◽  
Systematic Correction ◽  
Free Air ◽  
Wide Range ◽  
The Difference

Observations with a LaCoste and Romberg geodetic gravimeter having a very low nearly linear drift rate, a high reading precision, and a world wide range were made at approximately three hundred sites in order to check and extend the gravity control network in North America. The sites occupied were mostly at former gravimeter bases located at airports, harbors, universities, and pendulum stations. The instrument was calibrated against the North American standardization range of pendulum measurements from Paso de Cortes, Mexico, to Fairbanks, Alaska, using the weighted mean values of the observations established with the U. S. Coast and Geodetic Survey, Cambridge University (England), and Gulf‐University of Wisconsin pendulum equipment. A statistical evaluation of the precision of the network based on the reoccupations at 40 major control stations gives an estimated standard deviation of 0.08 mgal. The airport network of bases previously reported by Woollard (1958) that was established with high range Worden gravity meters was found to require a systematic correction of 0.3 mgal per 1,000 mgal change because of the difference in calibration standard used. The adjusted values for the forty airport stations reoccupied agree on the average to 0.2 mgal with the results of this study. The reoccupations of the old pendulum observation sites of the U. S. Coast and Goedetic Survey suggest that much of this network is in error by over 3 mgals. Descriptions of sites occupied and the principal facts for position, elevation, observed gravity, and free‐air and Bouguer anomalies are presented.

scholarly journals Imperialismo en el siglo XXI

2016 ◽  
Vol 6 (10) ◽  
pp. 49-74
Author(s):  
John Smith ◽  
Keyword(s):  
North America ◽  
Low Income ◽  
Great Part ◽  
Low Income Countries ◽  
Capitalist Development ◽  
Neoliberal Globalization ◽  
The North ◽  
Foreign Labor ◽  
Economic Foundation ◽  
The Difference

The globalization of production and its spread to low-income countries is the most notable transformation of the neoliberal era. Its driving force is the efforts by companies in Europe, North America and Japan to cut costs and raise profits, replacing relatively well-paid domestic labor for cheaper foreign labor. The gap in global wages, in great part the result of the suppression of the free movement of labor, provides a distorted view of the global differences in the rate of exploitation (simply, the difference between the value generated by the workers and what they are paid) upon which profits, prosperity and social peace in Europe, North America and Japan are ever-more reliant. Thus, neoliberal globalization should be seen as a new imperialist stage in capitalist development, where «imperialism» is defined by its economic foundation: the exploitation of labor in the South by capitalists from the North.

scholarly journals Hydrate and Wax Prevention in Flowlines by Electrical Heating

2000 ◽  
Author(s):  
Jens Kristian Lervik ◽  
Harald Kulbotten ◽  
Gunnar Klevjer ◽  
Øyvind Iversen
Keyword(s):  
Power Supply ◽  
Hydrate Formation ◽  
Magnetic Characteristic ◽  
Heating System ◽  
Electrical Heating ◽  
Oil Companies ◽  
Direct Heating ◽  
The North ◽  
Wide Range ◽  
The Difference

Traditional chemical treatment methods have considerable operation costs and represent a risk to the environment. Since 1987 Norwegian oil companies have been investigating alternative electrical heating methods for prevention of hydrate and wax plugs. A joint industry project ‘Concept Verification – Direct Heating of Oil & Gas Pipelines’ was initiated in 1996 and terminated in October 1999. During this work an electrical heating system was proved to be feasible on several fields in the North Sea. It will be installed on 7 flowlines of 13% Chromium (Crl3) with lengths between 6 km and 16 km. Electrical heating is used to maintain or raise the thermally insulated steel pipe temperature above the critical value for hydrate formation (typically 15–25 °C) or wax formation (typically 20–40°C). A single-phase power supply for the heating system is based on commercial components and connected to the platform power supply. The qualification work for the direct heating system has included full scale testing for single and parallel pipes, end termination at the template, bypass of a template and aspects concerning corrosion control. The rating of the system is dependent on the magnetic and electrical characteristics of the steel material. Such data is not commonly available. Measurements performed during the qualification program confirm that the magnetic characteristic may vary within a wide range for a specific steel quality and that mechanical stress and heat treatment can effect the magnetic characteristic. The difference in magnetic characteristic of individual Crl3 pipes results in variation of the pipe temperature and problems concerning differential pressure during melting. The problem can be handled by dividing the pipeline into a number of sections, each with a limited variation of the magnetic characteristic, thus keeping the temperature for the whole pipeline within acceptable limits. As a part of the pipe specification both electrical and magnetic characteristic should be available. These data can be determined by measuring arrangements in the production line of the mill. Measures to limit the variation of magnetic characteristic should be discussed.

scholarly journals Nitrogen oxides in the boundary layer and free troposphere at the Mt. Bachelor Observatory

2010 ◽  
Vol 10 (13) ◽  
pp. 6043-6062 ◽  
Author(s):  
D. R. Reidmiller ◽  
D. A. Jaffe ◽  
E. V. Fischer ◽  
B. Finley
Keyword(s):  
Boundary Layer ◽  
North America ◽  
Gulf Of Alaska ◽  
Aleutian Islands ◽  
Transport Pathways ◽  
North American Continent ◽  
Mixing Ratios ◽  
The North ◽  
Synoptic Conditions ◽  
The Difference

Abstract. Nitrogen oxide (NOx=NO+NO2) observations were made at the Mt. Bachelor Observatory in central Oregon, USA (MBO; 2.73 km above sea level) during one autumn and three springtime (15 April–20 May) periods. This is the first study to discuss interannual variability in NOx for this region. NOx concentrations (mean±1σ) for spring 2007, 2008 and 2009 were 119±65, 117±65, and 91±54 pptv, respectively. The difference in mean mixing ratios between 2007 and 2008 is not statistically significant, whereas the difference between these years and 2009 is significant (p<0.01). We attribute the decline in NOx from 2007–2008 to 2009 to changes in free tropospheric synoptic conditions over the Northeast Pacific and trans-Pacific transport pathways during spring 2009. In 2009, there were: (1) higher geopotential heights over the Gulf of Alaska, (2) warmer temperatures over the Aleutian Islands/Gulf of Alaska and (3) much weaker winds throughout the North Pacific. During the autumn 2008 campaign, NOx concentrations (mean±1σ) were 175±548 pptv. The highly non-normal distribution of data (skewness coefficient of 19.1 vs. 2.5, 2.8 and 2.4 in spring 2007, 2008 and 2009, respectively) resulted from periods of very high NOx levels. Using MODIS Rapid Response (Aqua and Terra) results, we show that during autumn our site can be heavily influenced by wildfires in western North America. This is in contrast to springtime, when the smaller positive (i.e., right) tail of the NOx distribution is driven largely by Asian long-range transport (ALRT) events. We developed a novel means of segregating boundary layer (BL)-influenced vs. free tropospheric (FT) air. During spring 2008 we collected "chairlift soundings" of temperature, relative humidity and pressure in an effort to better understand the diurnal pattern of a BL influence at our summit station. Results from this experiment revealed that, on average, a BL influence begins around 10:00 PDT (UTC – 07:00 h) in spring. Using this information to isolate FT air, we characterize probable pollution sources and synoptic conditions for the top 20 FT NOx events over three spring campaigns. Half (n=10) of these 20 events were determined to be "Imported" events characterized by anomalously: (1) high geopotential heights off the west coast of North America, (2) warm temperatures stretching from the Aleutian Islands to Baja California, and (3) strong southwesterly winds in the Asian outflow region. Five events exhibited an influence from the North American continent. These events are characterized by very strong cyclonic behavior off the northwestern USA coast.

A new approach to the measurement of the quantitative effects of inherent and environmental factors on the composition of the milk of individual cows and of herds, with particular reference to lactose content

1968 ◽  
Vol 35 (1) ◽  
pp. 91-105 ◽  
Author(s):  
J. P. Walsh ◽  
J. A. F. Rook ◽  
F. H. Dodd
Keyword(s):  
Quantitative Estimation ◽  
Relative Importance ◽  
New Approach ◽  
Mean Values ◽  
Stage Of Lactation ◽  
Bulk Milk ◽  
Wide Range ◽  
The Mean ◽  
The Difference ◽  
Effect Of Age

Summary(1) A tentative scheme is proposed for the quantitative estimation of the effects of various factors on one major milk constituent, lactose, from analyses of the milk of individual cows within herds. The potential lactose content in the milk of individual cows is predicted from the observed potassium-to-lactose ratio in the milk, and the difference between the predicted potential and the actual lactose content is partitioned into fractions that are attributed to effects due to age, inter-quarter difference and changes with stage of lactation. The scheme was applied to 2 commercial herds, one (herd A) producing milk of low and the other (herd B) milk of normal SNF content.(2) Lactation mean values for fat, SNF and lactose contents of the milk of individual cows showed a wide range of the same order in each of the 2 herds. Of the mean difference in SNF percentage of 0·30 between the herds, 0·14, or 47%, was due to a difference in lactose content.(3) The predicted potential milk lactose content of the cows in the 2 herds ranged from 5·04 to 5·66 (g/100 g milk water). Herd mean values were 5·394 for herd A and 5·244 for herd B.(4) Herd mean values for the effect on the lactose content (g/100 g milk water) of age, of changes with stage of lactation and of inter-quarter difference were −0·127, −0·080, and 0·073 respectively in herd A, and −0·197, −0·058 and −0·078, respectively, in herd B.(5) The relative importance of the various factors in accounting for differences between the herds in the lactose content of their bulk milk were: predicted potential lactose content 61%, effect of age 28%, effect of changes with stage of lactation 9% and effect of inter-quarter difference 2%.(6) The errors attached to the estimation of potential milk lactose content and the effects of age, of changes with stage of lactation and of inter-quarter difference are discussed.

scholarly journals Nitrogen oxides in the boundary layer and free troposphere at the Mt. Bachelor Observatory

2010 ◽  
Vol 10 (2) ◽  
pp. 5751-5801 ◽  
Author(s):  
D. R. Reidmiller ◽  
D. A. Jaffe ◽  
E. V. Fischer ◽  
B. Finley
Keyword(s):  
Boundary Layer ◽  
North America ◽  
Gulf Of Alaska ◽  
Aleutian Islands ◽  
Transport Pathways ◽  
North American Continent ◽  
Mixing Ratios ◽  
The North ◽  
Synoptic Conditions ◽  
The Difference

Abstract. Nitrogen oxide (NOx = NO + NO2) observations were made at the Mt. Bachelor Observatory in central Oregon, USA (MBO; 2.73 km above sea level) during one autumn and three springtime (15 April–20 May) periods. This is the first study to discuss interannual variability in NOx for this region. NOx concentrations (mean ±1σ) for spring 2007, 2008 and 2009 were 119±65, 117±65, and 91±54 pptv, respectively. The difference in mean mixing ratios between 2007 and 2008 is not statistically significant, whereas the difference between these years and 2009 is significant (p<0.01). We attribute the decline in NOx from 2007–2008 to 2009 to changes in free tropospheric synoptic conditions over the Northeast Pacific and trans-Pacific transport pathways during spring 2009. In 2009, there were: (1) higher geopotential heights over the Gulf of Alaska, (2) warmer temperatures over the Aleutian Islands/Gulf of Alaska and (3) much weaker winds throughout the North Pacific. During the autumn 2008 campaign, NOx concentrations (mean ±1σ) were 175±548 pptv. The highly non-normal distribution of data (skewness coefficient of 19.1 vs. 2.5, 2.8 and 2.4 in spring 2007, 2008 and 2009, respectively) resulted from periods of very high NOx levels. Using MODIS Rapid Response (Aqua and Terra) results, we show that during autumn our site can be heavily influenced by wildfires in western North America. This is in contrast to springtime, when the smaller positive (i.e., right) tail of the NOx distribution is driven largely by Asian long-range transport (ALRT) events. We developed a novel means of segregating boundary layer (BL)-influenced vs. free tropospheric (FT) air. During spring 2008 we collected "chairlift soundings" of temperature, relative humidity and pressure in an effort to better understand the diurnal pattern of a BL influence at our summit station. Results from this experiment revealed that, on average, a BL influence begins around 10:00 PDT (UTC – 7 h) in spring. Using this information to isolate FT air, we characterize probable pollution sources and synoptic conditions for the top 20 FT NOx events over three spring campaigns. Half (n = 10) of these 20 events were determined to be "Imported" events characterized by anomalously: (1) high geopotential heights off the west coast of North America, (2) warm temperatures stretching from the Aleutian Islands to Baja California, and (3) strong southwesterly winds in the Asian outflow region. Five events exhibited an influence from the North American continent. These events are characterized by very strong cyclonic behavior off the northwestern USA coast.

Comparative Precambrian geochronology of the North American, European, and Siberian Shields

1969 ◽  
Vol 6 (3) ◽  
pp. 357-365 ◽  
Author(s):  
R. A. Burwash
Keyword(s):  
Statistical Treatment ◽  
Geologic History ◽  
Northern Asia ◽  
North Central ◽  
Mean Values ◽  
The North ◽  
Central United States ◽  
History Of ◽  
The Difference ◽  
The Baltic

A comparison of average values of U–Pb, Rb–Sr, and K–Ar isotopic dates from Precambrian shields in North America, Europe, and northern Asia suggests three major orogenies common to all areas. U–Pb and Rb–Sr age determinations, qualified by the more numerous K–Ar data, suggest mean values of 2600 ± 100 m.y., 1800 ± 100 m.y. and 1000 ± 100 m.y. An earlier event at 3300 to 3500 m.y. is locally recognizable in the Baltic Shield, the Ukrainian Shield, and the north-central United States. Anorogenic igneous events intermediate between the major orogenies are indicated in the Canadian, Ukrainian, and Aldan Shields, but these are as yet unmatched outside their own restricted settings.Isotopic dates are divided into two categores: anorogenic and orogenic. Within a specified orogeny, dates are further divided into precrystalline, syncrystalline, and postcrystalline. Regional correlations ideally should be based only on syncrystalline dates, recording times of final crystallization, unmodified by subsequent processes except initial cooling. Depth of crystallization and rate of uplift determine the difference between true and apparent time of crystallization. Precrystalline dates (survival values) and postcrystalline (rejuvenated or overprinted) dates should be excluded from the designated span of major orogenies.Rigorous statistical treatment of isotopic dates seems unwarranted on the basis of uncertainties in the geologic history of most rock bodies. Histograms may aid in the identification of anorogenic and precrystalline dates.

New Records of California Serogroup Virus in Aedes Mosquitoes and First Detection in Simulioidae Flies from Northern Canada and Alaska

2021 ◽  
Author(s):  
Carol-Anne Villeneuve ◽  
Kayla J. Buhler ◽  
Mahmood Iranpour ◽  
Ellen Avard ◽  
Antonia Dibernardo ◽  
...  
Keyword(s):  
North America ◽  
Health Resources ◽  
Febrile Illness ◽  
The North ◽  
Standardized Protocol ◽  
Aedes Mosquitoes ◽  
Wide Range ◽  
North American Arctic ◽  
Serogroup Virus ◽  
California Serogroup

An expected consequence of climate warming is an expansion of the geographic distribution of biting insects and associated arthropod-borne diseases (arboviruses). Emerging and reemerging arboviruses that can affect human health are likely to pose significant consequences for Northern communities where access to health resources is limited. In the North American Arctic, little is known about arboviruses. Thus, in 2019, we sampled biting insects in Nunavik (Kuujjuaq), Nunavut (Igloolik, Karrak Lake and Cambridge Bay), Northwest Territories (Igloolik and Yellowknife) and Alaska (Fairbanks). The main objective was to detect the presence of California serogroup viruses (CSGv), a widespread group of arboviruses across North America and that is known to cause a wide range of symptoms, ranging from mild febrile illness to fatal encephalitis. Biting insects were captured twice daily for a 7-day period in mid-summer, using a standardized protocol consisting of 100 figure-eight movements of a sweep net. Captured specimens were separated by genus (mosquitoes) or by superfamily (other insects), and then grouped into pools of 75 by geographical locations. In total, 5079 Aedes mosquitoes and 1014 Simulioidae flies were caught. We report the detection of CSGv RNA in mosquitoes captured in Nunavut (Karrak Lake) and Nunavik (Kuujjuaq). We also report, for the first time in North America, the presence of CSGv RNA in Simulioidae flies. These results highlight the potential of biting insects for tracking any future emergence of arboviruses in the North, thereby providing key information for public health in Northern communities.

XVI. A table of the mean declination of the magnet in each decade from January 1858 to December 1863, derived from the observations made at the Magnetic Observatory at Lisbon; showing the annual variation, or semiannual inequality to which that element is subject. Drawn up by the superintendent of the Lisbon observatory, Senhor da Silveira, and communicated by Major-General Sabine, R. A., President of the Royal Society

1864 ◽  
Vol 13 ◽  
pp. 347-349
Keyword(s):  
Royal Society ◽  
Annual Variation ◽  
Secular Change ◽  
Magnetic Observatory ◽  
The Sun ◽  
The West ◽  
Mean Values ◽  
The North ◽  
The Mean ◽  
The Difference

I have much pleasure in communicating to the Fellows of the Royal Society a copy of a Table which I have received from the Superintendent of the Magnetic Observatory at Lisbon, containing the mean values of the Decimation in each Decade from the commencement of 1858 to the close of 1863, with corrections applied for the mean secular change, and showing, in a final column, the difference in each decade of the observed from the mean annual value derived from the 216 decades. This Table is a counter-part of Table VII. in Art. XII. of the Philosophical Transactions for 1863, p. 292, differing only in the substitution in the Lisbon Table of decades for weeks, and the addition of the year 1863. This general confirmation by the Lisbon Observatory of the annual variation to which the Declination is subject, “the north end of the magnet pointing more towards the East when the sun is north of the Equator, and more towards the West when the sun is south of the Equator,” is very satisfactory. In the Lisbon Table the disturbances have not been eliminated.

Lyell on the Geological Similarity of North America and Europe

1982 ◽  
Vol 1 (1) ◽  
pp. 45-47
Author(s):  
Leonard Wilson
Keyword(s):  
North America ◽  
Coastal Plain ◽  
North American ◽  
The United States ◽  
Atlantic Coastal Plain ◽  
Fossil Plants ◽  
Land Area ◽  
The North ◽  
The Difference ◽  
Atlantic Coastal

During his travels in America in 1841-1842 and 1845-1846, Charles Lyell was impressed by the difference of the living flora and fauna of North America from those of Europe. The fossil shells of the Cretaceous strata of New Jersey and of the Tertiary formations of the Atlantic Coastal Plain of the United States showed that North America had also constituted a separate biological region during the Cretaceous and throughout the Tertiary. By contrast, the fossil plants of North American coal formations were so closely similar to those of Europe that Lyell concluded that during the Carboniferous, Europe and North America must have formed a continuous land area. As evidence of a former land connection between North America and Europe, Lyell observed that the distribution of sediments among the strata of the Appalachians indicated that the Carboniferous strata of North America had been derived from land lying to the East — where the Atlantic Ocean now is. Similarly, the North American Silurian and other Paleozoic systems contained fossils similar to those of Europe, and their sediments were so distributed as to suggest that they had been derived from land lying to the East. Lyell pointed out the ancient uniformity of European and American fossil life, without being able to explain it.

Explaining globally inhomogeneous future changes in monsoons using simple moist energy diagnostics

2021 ◽  
pp. 1-45
Author(s):  
Rodrigo J. Bombardi ◽  
William R. Boos
Keyword(s):  
North America ◽  
South America ◽  
Southern Hemisphere ◽  
Northern Hemisphere ◽  
Southern Africa ◽  
Rainy Season ◽  
Coupled Model ◽  
Summer Precipitation ◽  
The North ◽  
The Difference

AbstractThis study examines the annual cycle of monsoon precipitation simulated by models from the Coupled Model Intercomparison Project phase 6 (CMIP6), then uses moist energy diagnostics to explain globally inhomogeneous projected future changes. Rainy season characteristics are quantified using a consistent method across the globe. Model bias is shown to include rainy season onsets tens of days later than observed in some monsoon regions (India, Australia, and North America) and overly large summer precipitation in others (North America, South America, and southern Africa). Projected next-century changes include rainy season lengthening in the two largest Northern Hemisphere monsoon regions (South Asia and central Sahel) and shortening in the two largest Southern Hemisphere regions (South America and southern Africa). Changes in the North American and Australian monsoons are less coherent across models. To understand these changes, relative moist static energy (MSE) is defined as the difference between local and tropical-mean surface air MSE. Future changes in relative MSE in each region correlate well with onset and demise date changes. Furthermore, Southern Hemisphere regions projected to undergo rainy season shortening are spanned by an increasing equator-to-pole MSE gradient, suggesting their rainfall will be increasingly inhibited by fluxes of dry extratropical air; Northern Hemisphere regions with projected lengthening of rainy seasons undergo little change in equator-to-pole MSE gradient. Thus, although model biases raise questions on the reliability of some projections, these results suggest that globally inhomogeneous future changes in monsoon timing may be understood through simple measures of surface air MSE.

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