The Relation Between Mantle Dynamics and Plate Tectonics
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Weather and Climate: Changing Human Exposures K
CHAPTER 2 Weather and climate: changing human exposures K. L. Ebi,1 L. O. Mearns,2 B. Nyenzi3 Introduction Research on the potential health effects of weather, climate variability and climate change requires understanding of the exposure of interest. Although often the terms weather and climate are used interchangeably, they actually represent different parts of the same spectrum. Weather is the complex and continuously changing condition of the atmosphere usually considered on a time-scale from minutes to weeks. The atmospheric variables that characterize weather include temperature, precipitation, humidity, pressure, and wind speed and direction. Climate is the average state of the atmosphere, and the associated characteristics of the underlying land or water, in a particular region over a par- ticular time-scale, usually considered over multiple years. Climate variability is the variation around the average climate, including seasonal variations as well as large-scale variations in atmospheric and ocean circulation such as the El Niño/Southern Oscillation (ENSO) or the North Atlantic Oscillation (NAO). Climate change operates over decades or longer time-scales. Research on the health impacts of climate variability and change aims to increase understanding of the potential risks and to identify effective adaptation options. Understanding the potential health consequences of climate change requires the development of empirical knowledge in three areas (1): 1. historical analogue studies to estimate, for specified populations, the risks of climate-sensitive diseases (including understanding the mechanism of effect) and to forecast the potential health effects of comparable exposures either in different geographical regions or in the future; 2. studies seeking early evidence of changes, in either health risk indicators or health status, occurring in response to actual climate change; 3. -
Environmental Systems the Atmosphere and Hydrosphere
Environmental Systems The atmosphere and hydrosphere THE ATMOSPHERE The atmosphere, the gaseous layer that surrounds the earth, formed over four billion years ago. During the evolution of the solid earth, volcanic eruptions released gases into the developing atmosphere. Assuming the outgassing was similar to that of modern volcanoes, the gases released included: water vapor (H2O), carbon monoxide (CO), carbon dioxide (CO2), hydrochloric acid (HCl), methane (CH4), ammonia (NH3), nitrogen (N2) and sulfur gases. The atmosphere was reducing because there was no free oxygen. Most of the hydrogen and helium that outgassed would have eventually escaped into outer space due to the inability of the earth's gravity to hold on to their small masses. There may have also been significant contributions of volatiles from the massive meteoritic bombardments known to have occurred early in the earth's history. Water vapor in the atmosphere condensed and rained down, of radiant energy in the atmosphere. The sun's radiation spans the eventually forming lakes and oceans. The oceans provided homes infrared, visible and ultraviolet light regions, while the earth's for the earliest organisms which were probably similar to radiation is mostly infrared. cyanobacteria. Oxygen was released into the atmosphere by these early organisms, and carbon became sequestered in sedimentary The vertical temperature profile of the atmosphere is variable and rocks. This led to our current oxidizing atmosphere, which is mostly depends upon the types of radiation that affect each atmospheric comprised of nitrogen (roughly 71 percent) and oxygen (roughly 28 layer. This, in turn, depends upon the chemical composition of that percent). -
Slab Pull? Density of Plate Slab
The plate tectonic story www.earthscienceeducation.com Geography Workshop GA Conference 2021 Duncan Hawley in association with the Earth Science Education Unit and EarthLearningIdea www.earthlearningidea.com Image: Free download https://www.kissclipart.com/visual-tectonic-plates-clipart-crust-earth-plate-t-nnw9dx/ The plate tectonic story www.earthscienceeducation.com Aims of this session The workshop and its activities aims to: • provide an integrated overview of the concepts involved in teaching the processes of plate tectonics at KS3, KS4 and A level • survey of some of the recent evidence and key ideas in understanding how plate tectonics works • offer improved explanations for the distribution and characteristics of volcanoes, earthquakes, and some surface landforms • suggest approaches to teaching the abstract concepts of plate tectonics • help teachers decide if and how they should adjust what they presently teach to reflect the current understanding about the way plate tectonics operates • help teachers develop students’ critical sense of ‘the plate tectonic story’ encountered in textbooks, on diagrams, on the news, via the internet and in other media. The plate tectonic story www.earthscienceeducation.com Where on Earth are earthquakes and volcanoes? - geobattleships www.earthlearningidea.com/PDF/79_Geobattleships.pdf Battleship grid for Geobattleships © Dave Turner Galunggung eruption by USGS, public domain ‘North All Trucks’ © USGS The plate tectonic story www.earthscienceeducation.com Where on Earth are earthquakes and volcanoes? -
Wind Energy Forecasting: a Collaboration of the National Center for Atmospheric Research (NCAR) and Xcel Energy
Wind Energy Forecasting: A Collaboration of the National Center for Atmospheric Research (NCAR) and Xcel Energy Keith Parks Xcel Energy Denver, Colorado Yih-Huei Wan National Renewable Energy Laboratory Golden, Colorado Gerry Wiener and Yubao Liu University Corporation for Atmospheric Research (UCAR) Boulder, Colorado NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency & Renewable Energy, operated by the Alliance for Sustainable Energy, LLC. S ubcontract Report NREL/SR-5500-52233 October 2011 Contract No. DE-AC36-08GO28308 Wind Energy Forecasting: A Collaboration of the National Center for Atmospheric Research (NCAR) and Xcel Energy Keith Parks Xcel Energy Denver, Colorado Yih-Huei Wan National Renewable Energy Laboratory Golden, Colorado Gerry Wiener and Yubao Liu University Corporation for Atmospheric Research (UCAR) Boulder, Colorado NREL Technical Monitor: Erik Ela Prepared under Subcontract No. AFW-0-99427-01 NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency & Renewable Energy, operated by the Alliance for Sustainable Energy, LLC. National Renewable Energy Laboratory Subcontract Report 1617 Cole Boulevard NREL/SR-5500-52233 Golden, Colorado 80401 October 2011 303-275-3000 • www.nrel.gov Contract No. DE-AC36-08GO28308 This publication received minimal editorial review at NREL. NOTICE This report was prepared as an account of work sponsored by an agency of the United States government. Neither the United States government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. -
Wind Characteristics 1 Meteorology of Wind
Chapter 2—Wind Characteristics 2–1 WIND CHARACTERISTICS The wind blows to the south and goes round to the north:, round and round goes the wind, and on its circuits the wind returns. Ecclesiastes 1:6 The earth’s atmosphere can be modeled as a gigantic heat engine. It extracts energy from one reservoir (the sun) and delivers heat to another reservoir at a lower temperature (space). In the process, work is done on the gases in the atmosphere and upon the earth-atmosphere boundary. There will be regions where the air pressure is temporarily higher or lower than average. This difference in air pressure causes atmospheric gases or wind to flow from the region of higher pressure to that of lower pressure. These regions are typically hundreds of kilometers in diameter. Solar radiation, evaporation of water, cloud cover, and surface roughness all play important roles in determining the conditions of the atmosphere. The study of the interactions between these effects is a complex subject called meteorology, which is covered by many excellent textbooks.[4, 8, 20] Therefore only a brief introduction to that part of meteorology concerning the flow of wind will be given in this text. 1 METEOROLOGY OF WIND The basic driving force of air movement is a difference in air pressure between two regions. This air pressure is described by several physical laws. One of these is Boyle’s law, which states that the product of pressure and volume of a gas at a constant temperature must be a constant, or p1V1 = p2V2 (1) Another law is Charles’ law, which states that, for constant pressure, the volume of a gas varies directly with absolute temperature. -
Slab-Pull and Slab-Push Earthquakes in the Mexican, Chilean and Peruvian Subduction Zones A
Physics of the Earth and Planetary Interiors 132 (2002) 157–175 Slab-pull and slab-push earthquakes in the Mexican, Chilean and Peruvian subduction zones A. Lemoine a,∗, R. Madariaga a, J. Campos b a Laboratoire de Géologie, Ecole Normale Supérieure, 24 Rue Lhomond, 75231 Paris Cedex 05, France b Departamento de Geof´ısica, Universidad de Chile, Santiago, Chile Abstract We studied intermediate depth earthquakes in the Chile, Peru and Mexican subduction zones, paying special attention to slab-push (down-dip compression) and slab-pull (down-dip extension) mechanisms. Although, slab-push events are relatively rare in comparison with slab-pull earthquakes, quite a few have occurred recently. In Peru, a couple slab-push events occurred in 1991 and one slab-pull together with several slab-push events occurred in 1970 near Chimbote. In Mexico, several slab-push and slab-pull events occurred near Zihuatanejo below the fault zone of the 1985 Michoacan event. In central Chile, a large M = 7.1 slab-push event occurred in October 1997 that followed a series of four shallow Mw > 6 thrust earthquakes on the plate interface. We used teleseismic body waveform inversion of a number of Mw > 5.9 slab-push and slab-pull earthquakes in order to obtain accurate mechanisms, depths and source time functions. We used a master event method in order to get relative locations. We discussed the occurrence of the relatively rare slab-push events in the three subduction zones. Were they due to the geometry of the subduction that produces flexure inside the downgoing slab, or were they produced by stress transfer during the earthquake cycle? Stress transfer can not explain the occurence of several compressional and extensional intraplate intermediate depth earthquakes in central Chile, central Mexico and central Peru. -
GLY5455 Introduction to Geophysics/Geodynamics Syllabus Fall 2015 Instructor: Mark Panning Location: Williamson 218 Time: Tuesday and Thursday, 1:55-3:10Pm
GLY5455 Introduction to Geophysics/Geodynamics Syllabus Fall 2015 Instructor: Mark Panning Location: Williamson 218 Time: Tuesday and Thursday, 1:55-3:10pm Contact Info Office: 229 Williamson Hall Phone: 392-2634 Email: [email protected] Office hours: Can be arranged at any time via email Textbook Turcotte & Schubert, Geodynamics, 3rd Edition (required) We will also be pulling material from the following books (not required) Physics of the Earth, Stacey and Davis (2008) The Magnetic Field of the Earth, Merrill, McElhinny, and McFadden (1996) Introduction to Seismology, Shearer (2006) Pre-reqs You will ideally have completed 1 year of calculus and a semester of physics. This class will deal with vector calculus… if this worries you, check out div grad curl and all that, by H.M. Schey (available for around $30 online). Grading 60% Homework 20% Midterm 20% Final Course topics (roughly 2-3 weeks per topic… but very flexible!) Topic Text Gravity Ch. 5 + other notes Heat Ch. 4 Magnetism Material from The Magnetic Field of the Earth Seismology Ch. 2, 3, and material from Introduction to Seismology Plate Tectonics & Mantle Geodynamics Ch. 1,6,7 Geophysical inverse theory (if time allows) Outside readings TBA Class notes Lecture notes will be distributed, sometimes before the material is covered in lecture, and sometimes after. Regardless, as always, such notes are meant to be supplementary to your own notes. I may cover things not in the distributed notes, and likewise may not cover everything in lecture that is included in the notes. Homework The first homework assignment will be assigned in week 2. -
Geodynamics and Rate of Volcanism on Massive Earth-Like Planets
The Astrophysical Journal, 700:1732–1749, 2009 August 1 doi:10.1088/0004-637X/700/2/1732 C 2009. The American Astronomical Society. All rights reserved. Printed in the U.S.A. GEODYNAMICS AND RATE OF VOLCANISM ON MASSIVE EARTH-LIKE PLANETS E. S. Kite1,3, M. Manga1,3, and E. Gaidos2 1 Department of Earth and Planetary Science, University of California at Berkeley, Berkeley, CA 94720, USA; [email protected] 2 Department of Geology and Geophysics, University of Hawaii at Manoa, Honolulu, HI 96822, USA Received 2008 September 12; accepted 2009 May 29; published 2009 July 16 ABSTRACT We provide estimates of volcanism versus time for planets with Earth-like composition and masses 0.25–25 M⊕, as a step toward predicting atmospheric mass on extrasolar rocky planets. Volcanism requires melting of the silicate mantle. We use a thermal evolution model, calibrated against Earth, in combination with standard melting models, to explore the dependence of convection-driven decompression mantle melting on planet mass. We show that (1) volcanism is likely to proceed on massive planets with plate tectonics over the main-sequence lifetime of the parent star; (2) crustal thickness (and melting rate normalized to planet mass) is weakly dependent on planet mass; (3) stagnant lid planets live fast (they have higher rates of melting than their plate tectonic counterparts early in their thermal evolution), but die young (melting shuts down after a few Gyr); (4) plate tectonics may not operate on high-mass planets because of the production of buoyant crust which is difficult to subduct; and (5) melting is necessary but insufficient for efficient volcanic degassing—volatiles partition into the earliest, deepest melts, which may be denser than the residue and sink to the base of the mantle on young, massive planets. -
ASSESSMENT of the TSUNAMIGENIC POTENTIAL ALONG the NORTHERN CARIBBEAN MARGIN Case Study: Earthquake and Tsunamis of 12 January 2010 in Haiti
ISSN 87556839 SCIENCE OF TSUNAMI HAZARDS Journal of Tsunami Society International Volume 29 Number 3 2010 ASSESSMENT OF THE TSUNAMIGENIC POTENTIAL ALONG THE NORTHERN CARIBBEAN MARGIN Case Study: Earthquake and Tsunamis of 12 January 2010 in Haiti. George Pararas-Carayannis Tsunami Society International, Honolulu, Hawaii 96815, USA [email protected] ABSTRACT The potential tsunami risk for Hispaniola, as well as for the other Greater Antilles Islands is assessed by reviewing the complex geotectonic processes and regimes along the Northern Caribbean margin, including the convergent, compressional and collisional tectonic activity of subduction, transition, shearing, lateral movements, accretion and crustal deformation caused by the eastward movement of the Caribbean plate in relation to the North American plate. These complex tectonic interactions have created a broad, diffuse tectonic boundary that has resulted in an extensive, internal deformational sliver slab - the Gonâve microplate – as well as further segmentation into two other microplates with similarly diffused boundary characteristics where tsunamigenic earthquakes have and will again occur. The Gonâve microplate is the most prominent along the Northern Caribbean margin and extends from the Cayman Spreading Center to Mona Pass, between Puerto Rico and the island of Hispaniola, where the 1918 destructive tsunami was generated. The northern boundary of this sliver microplate is defined by the Oriente strike-slip fault south of Cuba, which appears to be an extension of the fault system traversing the northern part of Hispaniola, while the southern boundary is defined by another major strike-slip fault zone where the Haiti earthquake of 12 January 2010 occurred. Potentially tsunamigenic regions along the Northern Caribbean margin are located not only along the boundaries of the Gonâve microplate’s dominant western transform zone but particularly within the eastern tectonic regimes of the margin where subduction is dominant - particularly along the Puerto Rico trench. -
Geological Evolution of the Red Sea: Historical Background, Review and Synthesis
See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/277310102 Geological Evolution of the Red Sea: Historical Background, Review and Synthesis Chapter · January 2015 DOI: 10.1007/978-3-662-45201-1_3 CITATIONS READS 6 911 1 author: William Bosworth Apache Egypt Companies 70 PUBLICATIONS 2,954 CITATIONS SEE PROFILE Some of the authors of this publication are also working on these related projects: Near and Middle East and Eastern Africa: Tectonics, geodynamics, satellite gravimetry, magnetic (airborne and satellite), paleomagnetic reconstructions, thermics, seismics, seismology, 3D gravity- magnetic field modeling, GPS, different transformations and filtering, advanced integrated examination. View project Neotectonics of the Red Sea rift system View project All content following this page was uploaded by William Bosworth on 28 May 2015. The user has requested enhancement of the downloaded file. All in-text references underlined in blue are added to the original document and are linked to publications on ResearchGate, letting you access and read them immediately. Geological Evolution of the Red Sea: Historical Background, Review, and Synthesis William Bosworth Abstract The Red Sea is part of an extensive rift system that includes from south to north the oceanic Sheba Ridge, the Gulf of Aden, the Afar region, the Red Sea, the Gulf of Aqaba, the Gulf of Suez, and the Cairo basalt province. Historical interest in this area has stemmed from many causes with diverse objectives, but it is best known as a potential model for how continental lithosphere first ruptures and then evolves to oceanic spreading, a key segment of the Wilson cycle and plate tectonics. -
Archimedean Proof of the Physical Impossibility of Earth Mantle Convection by J. Marvin Herndon Transdyne Corporation San Diego
Archimedean Proof of the Physical Impossibility of Earth Mantle Convection by J. Marvin Herndon Transdyne Corporation San Diego, CA 92131 USA [email protected] Abstract: Eight decades ago, Arthur Holmes introduced the idea of mantle convection as a mechanism for continental drift. Five decades ago, continental drift was modified to become plate tectonics theory, which included mantle convection as an absolutely critical component. Using the submarine design and operation concept of “neutral buoyancy”, which follows from Archimedes’ discoveries, the concept of mantle convection is proven to be incorrect, concomitantly refuting plate tectonics, refuting all mantle convection models, and refuting all models that depend upon mantle convection. 1 Introduction Discovering the true nature of continental displacement, its underlying mechanism, and its energy source are among the most fundamental geo-science challenges. The seeming continuity of geological structures and fossil life-forms on either side of the Atlantic Ocean and the apparent “fit’ of their opposing coastlines led Antonio Snider-Pellegrini to propose in 1858, as shown in Fig. 1, that the Americas were at one time connected to Europe and Africa and subsequently separated, opening the Atlantic Ocean (Snider-Pellegrini, 1858). Fig. 1 The opening of the Atlantic Ocean, reproduced from (Snider-Pellegrini, 1858). 1 Half a century later, Alfred Wegener promulgated a similar concept, with more detailed justification, that became known as “continental drift” (Wegener, 1912). Another half century later, continental drift theory was modified to become plate tectonics theory (Dietz, 1961;Hess, 1962;Le Pichon, 1968;Vine and Matthews, 1963). Any theory of continental displacement requires a physically realistic mechanism and an adequate energy source. -
(2 Points Each) 1. the Velocity Of
GG 101, Spring 2006 Name_________________________ Exam 2, March 9, 2006 A. Fill in the blank (2 points each) 1. The velocity of an S-wave is ______lower_________ than the velocity of a P-wave. 2. What type of seismic wave is being recorded by the above diagram? A __P__ wave. 3. The most voluminous layer of Earth is the ___mantle_________. 4. The rigid layer of Earth which consists of the crust and uppermost mantle is called the __ lithosphere__________. 5. Which of the major subdivisions of Earth's interior is thought to be liquid? ____outer core________. 6. When the giant ice sheets in the northern hemisphere melted after the last ice age, the Earth's crust ____rebounded____ because a large weight was removed. Name _______________________________ GG 101 Exam 2 Page 2 7. The process described in question 6 is an example of ___isostasy____. 8. Earth's dense core is thought to consist predominantly of ____iron________. 9. The island of Hawaii experiences volcanism because it is located above a(n) ___hot spot_________. 10. The Himalaya Mountains were caused by ___collision__ between ___India__________ and Asia. 11. ___Folds____ are the most common ductile response to stress on rocks in the earth’s crust. 12. ___Faults___ are the most common brittle response to stress on rocks in the earth’s crust. 13. What types of faults are depicted in the cross section shown above? ___thrust_______ faults. Name _______________________________ GG 101 Exam 2 Page 3 14. The structure shown in the above diagram is a(n) ____anticline_____. 15. The name of a fold that occurs in an area of intense deformation where one limb of the fold has been tilted beyond the vertical is called a(n) ____overturned____ fold.