Climate and Atmospheric Circulation of Mars
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How the Ocean Affects Weather & Climate
Ocean in Motion 6: How does the Ocean Change Weather and Climate? A. Overview 1. The Ocean in Motion -- Weather and Climate In this program we will tie together ideas from previous lectures on ocean circulation. The students will also learn about the similarities and interactions between the atmosphere and the ocean. 2. Contents of Packet Your packet contains the following activities: I. A Sea of Words B. Program Preparation 1. Focus Points OThe oceans and the atmosphere are closely linked 1. the sun heats the atmosphere as well as the oceans 2. water evaporates from the ocean into the atmosphere a. forms clouds and precipitation b. movement of any fluid (gas or liquid) due to heating creates convective currents OWeather and climate are two different things. 1. Winds a. Uneven heating and cooling of the atmosphere creates wind b. Global ocean surface current patterns are similar to global surface wind patterns c. wind patterns are analogous to ocean currents 2. Four seasons OAtmospheric motion 1. weather and air moves from high to low pressure areas 2. the earth's rotation also influences air and weather patterns 3. Atmospheric winds move surface ocean currents. ©1998 Project Oceanography Spring Series Ocean in Motion 1 C. Showtime 1. Broadcast Topics This broadcast will link into discussions on ocean and atmospheric circulation, wind patterns, and how climate and weather are two different things. a. Brief Review We know the modern reason for studying ocean circulation is because it is a major part of our climate. We talked about how the sun provides heat energy to the world, and how the ocean currents circulate because the water temperatures and densities vary. -
3 Atmospheric Motion
Final PDF to printer CHAPTER 3 Atmospheric Motion MOTION OF THE EARTH’S ATMOSPHERE has a great influence on human lives by controlling climate, rainfall, weather patterns, and long-range transportation. It is driven largely by differences in insolation, with influences from other factors, including topography, land-sea interfaces, and especially rotation of the planet. These factors control motion at local scales, like between a mountain and valley, at larger scales encompassing major storm systems, and at global scales, determining the prevailing wind directions for the broader planet. All of these circulations are governed by similar physical principles, which explain wind, weather patterns, and climate. Broad-scale patterns of atmospheric circulation are shown here for the Northern Hemisphere. Examine all the components on this figure and think about what you know about each. Do you recognize some of the features and names? Two features on this figure are identified with the term “jet stream.” You may have heard this term watching the nightly weather report or from a captain on a cross-country airline flight. What is a jet stream and what effect does it have on weather and flying? Prominent labels of H and L represent areas with relatively higher and lower air pressure, respectively. What is air pressure and why do some areas have higher or lower pressure than other areas? Distinctive wind patterns, shown by white arrows, are associated with the areas of high and low pressure. The winds are flowing outward and in a clockwise direction from the high, but inward and in a counterclockwise direction from the low. -
Chapter 7 100 Years of the Ocean General Circulation
CHAPTER 7 WUNSCH AND FERRARI 7.1 Chapter 7 100 Years of the Ocean General Circulation CARL WUNSCH Massachusetts Institute of Technology, and Harvard University, Cambridge, Massachusetts RAFFAELE FERRARI Massachusetts Institute of Technology, Cambridge, Massachusetts ABSTRACT The central change in understanding of the ocean circulation during the past 100 years has been its emergence as an intensely time-dependent, effectively turbulent and wave-dominated, flow. Early technol- ogies for making the difficult observations were adequate only to depict large-scale, quasi-steady flows. With the electronic revolution of the past 501 years, the emergence of geophysical fluid dynamics, the strongly inhomogeneous time-dependent nature of oceanic circulation physics finally emerged. Mesoscale (balanced), submesoscale oceanic eddies at 100-km horizontal scales and shorter, and internal waves are now known to be central to much of the behavior of the system. Ocean circulation is now recognized to involve both eddies and larger-scale flows with dominant elements and their interactions varying among the classical gyres, the boundary current regions, the Southern Ocean, and the tropics. 1. Introduction physical regimes, understanding of the ocean until relatively recently greatly lagged that of the atmo- In the past 100 years, understanding of the general sphere. As in almost all of fluid dynamics, progress circulation of the ocean has shifted from treating it as an in understanding has required an intimate partnership essentially laminar, steady-state, slow, almost geological, between theoretical description and observational or flow, to that of a perpetually changing fluid, best charac- laboratory tests. The basic feature of the fluid dynamics terized as intensely turbulent with kinetic energy domi- of the ocean, as opposed to that of the atmosphere, has nated by time-varying flows. -
El Niño and La Niña
About the Images What are El Niño and La Niña? The images show El Niño, neutral, and La Niña sea surface The naturally occurring El Niño and La Niña phenomenon rep- heights (SSHs) relative to a reference state established in resents a “dance” between the atmosphere and ocean in the 1992. In the equatorial region of the Pacific Ocean, the SSH equatorial Pacific Ocean. Sometimes the atmosphere leads the during El Niño was higher by more than 18 cm over a large ocean and causes ocean conditions, and sometimes the ocean longitudinal region. The warmer water associated with El Niño leads the atmosphere and produces atmospheric motions that— displaces colder water in the upper layer of the ocean causing when strong enough—influence global atmospheric circulation. an increase in SSH because of thermal expansion. During La Sea surface temperature (SST) is the critical variable connecting Niña the temperature of the upper ocean is lower than normal, the atmosphere and ocean. Since SSH measurements yield criti- causing SSH to decrease because of thermal contraction. The cal information about the depth of the subsurface temperatures, neutral condition occurs when the upper-ocean temperature e.g., the thermocline, they provide key information on the onset, is “normal.” Red and white shades indicate high SSHs relative maintenance, and dissipation of El Niño and La Niña events. to the reference state, while blue and purple shades indicate SSHs lower than the reference state. Neutral conditions appear The 2015 El Niño Event green. The El Niño and neutral images are derived using data After five consecutive months with SSTs 0.5 °C above the acquired by the Ocean Surface Topography Mission (OSTM)/Jason-2 long-term mean, the National Oceanic and Atmospheric Admin- satellite. -
Atmospheric General Circulation
LectureLecture 5:5: AtmosphericAtmospheric GeneralGeneral CirculationCirculation JS JP HadleyHadley CellCell FerrelFerrel CellCell PolarPolar CellCell (driven by eddies) LHL H Basic Structures and Dynamics General Circulation in the Troposphere General Circulation in the Stratosphere Wind-Driven Ocean Circulation ESS55 Prof. Jin-Yi Yu SingleSingle--CellCell Model:Model: ExplainsExplains WhyWhy ThereThere areare TropicalTropical EasterliesEasterlies Without Earth Rotation With Earth Rotation Coriolis Force (Figures from Understanding Weather & Climate and The Earth System) ESS55 Prof. Jin-Yi Yu BreakdownBreakdown ofof thethe SingleSingle CellCell ÎÎ ThreeThree--CellCell ModelModel Absolute angular momentum at Equator = Absolute angular momentum at 60°N The observed zonal velocity at the equatoru is ueq = -5 m/sec. Therefore, the total velocity at the equator is U=rotational velocity (U0 + uEq) The zonal wind velocity at 60°N (u60N) can be determined by the following: (U0 + uEq) * a * Cos(0°) = (U60N + u60N) * a * Cos(60°) (Ω*a*Cos0° - 5) * a * Cos0° = (Ω*a*Cos60° + u60N) * a * Cos(60°) u60N = 687 m/sec !!!! This high wind speed is not observed! ESS55 Prof. Jin-Yi Yu PropertiesProperties ofof thethe ThreeThree CellsCells thermally indirect circulation thermally direct circulation JS JP HadleyHadley CellCell FerrelFerrel CellCell PolarPolar CellCell (driven by eddies) LHL H Equator 30° 60° Pole (warmer) (warm) (cold) (colder) ESS55 Prof. Jin-Yi Yu AtmosphericAtmospheric Circulation:Circulation: ZonalZonal--meanmean ViewsViews Single-Cell Model Three-Cell Model (Figures from Understanding Weather & Climate and The Earth System) ESS55 Prof. Jin-Yi Yu TheThe ThreeThree CellsCells ITCZ Subtropical midlatitude High Weather system (Figures from Understanding Weather & Climate and The Earth System) ESS55 Prof. Jin-Yi Yu ThermallyThermally Direct/IndirectDirect/Indirect CellsCells Thermally Direct Cells (Hadley and Polar Cells) Both cells have their rising branches over warm temperature zones and sinking braches over the cold temperature zone. -
History of Frontal Concepts Tn Meteorology
HISTORY OF FRONTAL CONCEPTS TN METEOROLOGY: THE ACCEPTANCE OF THE NORWEGIAN THEORY by Gardner Perry III Submitted in Partial Fulfillment of the Requirements for the Degree of Bachelor of Science at the MASSACHUSETTS INSTITUTE OF TECHNOLOGY June, 1961 Signature of'Author . ~ . ........ Department of Humangties, May 17, 1959 Certified by . v/ .-- '-- -T * ~ . ..... Thesis Supervisor Accepted by Chairman0 0 e 0 o mmite0 0 Chairman, Departmental Committee on Theses II ACKNOWLEDGMENTS The research for and the development of this thesis could not have been nearly as complete as it is without the assistance of innumerable persons; to any that I may have momentarily forgotten, my sincerest apologies. Conversations with Professors Giorgio de Santilw lana and Huston Smith provided many helpful and stimulat- ing thoughts. Professor Frederick Sanders injected thought pro- voking and clarifying comments at precisely the correct moments. This contribution has proven invaluable. The personnel of the following libraries were most cooperative with my many requests for assistance: Human- ities Library (M.I.T.), Science Library (M.I.T.), Engineer- ing Library (M.I.T.), Gordon MacKay Library (Harvard), and the Weather Bureau Library (Suitland, Md.). Also, the American Meteorological Society and Mr. David Ludlum were helpful in suggesting sources of material. In getting through the myriad of minor technical details Professor Roy Lamson and Mrs. Blender were indis-. pensable. And finally, whatever typing that I could not find time to do my wife, Mary, has willingly done. ABSTRACT The frontal concept, as developed by the Norwegian Meteorologists, is the foundation of modern synoptic mete- orology. The Norwegian theory, when presented, was rapidly accepted by the world's meteorologists, even though its several precursors had been rejected or Ignored. -
The Earth's Rotation and Atmospheric Circulation, from 1963 to 1973 Kurt
Geophys. J. R. astr. Soc. (1981) 64,67-89 The Earth’s rotation and atmospheric circulation, from 1963 to 1973 Kurt Lambeck and Peter Hopgood Research School of Earth Sciences, Australian National University, Canberra 2600, Australia Received 1980 June 13; in original form 1980 March 17 ‘If everybody minded their own business, the world would go round a deal faster than it does.’ Alice’s Adventures in Wonderland Lewis Carroll Summary. The zonal angular momentum of the atmospheric circulation has been evaluated month-by-month and compared with astronomical observa- tions of the length-of-day for the 10 years from 1963 May to 1973 April. The reason for undertaking this study is to enable the astronomical observa- tions to be ‘corrected’ for the zonal wind effect and to investigate the residual excitation function for solid-Earth contributions. The principal conclusions reached are the following: (i) The annual change in length-of-day is almost entirely due to the seasonal changes in the zonal circulation with tidal, oceanographic and hydrologic phenomena contributing together at most 10 per cent of the total excitation. (ii) The semi-annual term is pre- dominantly due to the zonal wind and the body tide, with oceanic and hydrologic terms contributing about 10 per cent. (iii) The atmospheric circulation plays a dominant role in length-of-day changes in the period range from 1 to about 4 yr. This is partly associated with the quasi-biennial oscilla- tion and its harmonics. Both the period and amplitude of these fluctuations are very variable. (iv) At longer periods the atmosphere may still contribute to the total excitation but other excitation functions begin to rise above the spectrum of the meteorological excitation. -
Atmospheric Circulation and Weather Systems
CHAPTER ATMOSPHERIC CIRCULATION AND WEATHER SYSTEMS arlier Chapter 9 described the uneven pressure is measured with the help of a distribution of temperature over the mercury barometer or the aneroid barometer. Esurface of the earth. Air expands when Consult your book, Practical Work in heated and gets compressed when cooled. This Geography — Part I (NCERT, 2006) and learn results in variations in the atmospheric about these instruments. The pressure pressure. The result is that it causes the decreases with height. At any elevation it varies movement of air from high pressure to low from place to place and its variation is the pressure, setting the air in motion. You already primary cause of air motion, i.e. wind which know that air in horizontal motion is wind. moves from high pressure areas to low Atmospheric pressure also determines when pressure areas. the air will rise or sink. The wind redistributes the heat and moisture across the planet, Vertical Variation of Pressure thereby, maintaining a constant temperature In the lower atmosphere the pressure for the planet as a whole. The vertical rising of decreases rapidly with height. The decrease moist air cools it down to form the clouds and amounts to about 1 mb for each 10 m bring precipitation. This chapter has been increase in elevation. It does not always devoted to explain the causes of pressure decrease at the same rate. Table 10.1 gives differences, the forces that control the the average pressure and temperature at atmospheric circulation, the turbulent pattern selected levels of elevation for a standard of wind, the formation of air masses, the atmosphere. -
Ocean Circulation and Climate: a 21St Century Perspective
Chapter 13 Western Boundary Currents Shiro Imawaki*, Amy S. Bower{, Lisa Beal{ and Bo Qiu} *Japan Agency for Marine–Earth Science and Technology, Yokohama, Japan {Woods Hole Oceanographic Institution, Woods Hole, Massachusetts, USA {Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, Florida, USA }School of Ocean and Earth Science and Technology, University of Hawaii, Honolulu, Hawaii, USA Chapter Outline 1. General Features 305 4.1.3. Velocity and Transport 317 1.1. Introduction 305 4.1.4. Separation from the Western Boundary 317 1.2. Wind-Driven and Thermohaline Circulations 306 4.1.5. WBC Extension 319 1.3. Transport 306 4.1.6. Air–Sea Interaction and Implications 1.4. Variability 306 for Climate 319 1.5. Structure of WBCs 306 4.2. Agulhas Current 320 1.6. Air–Sea Fluxes 308 4.2.1. Introduction 320 1.7. Observations 309 4.2.2. Origins and Source Waters 320 1.8. WBCs of Individual Ocean Basins 309 4.2.3. Velocity and Vorticity Structure 320 2. North Atlantic 309 4.2.4. Separation, Retroflection, and Leakage 322 2.1. Introduction 309 4.2.5. WBC Extension 322 2.2. Florida Current 310 4.2.6. Air–Sea Interaction 323 2.3. Gulf Stream Separation 311 4.2.7. Implications for Climate 323 2.4. Gulf Stream Extension 311 5. North Pacific 323 2.5. Air–Sea Interaction 313 5.1. Upstream Kuroshio 323 2.6. North Atlantic Current 314 5.2. Kuroshio South of Japan 325 3. South Atlantic 315 5.3. Kuroshio Extension 325 3.1. -
Lecture 6 Winds: Atmosphere and Ocean Circulation
Lecture 6 Winds: Atmosphere and Ocean Circulation The global atmospheric circulation and its seasonal variability is driven by the uneven solar heating of the Earth’s atmosphere and surface. Solar radiation on a planet at different axial inclinations. The concept of flux density (1/d2, energy/time/area) and the cosine law. Because Earth’s rotation axis is tilted relative to the plane of its orbit around the sun, there is seasonal variability in the geographical distribution of sunshine March 21, vernal equinox December 21, winter solstice June 21, summer solstice September 23, autumnal equinox Zonally averaged components of the annual mean absorbed solar flux, emitted Earth’s infrared flux, and net radiative flux at the top of the atmosphere, derived from satellite observations. + _ _ The geographical distribution of temperature and its seasonal variability closely follows the geographical distribution of sunshine (solar radiation). Temperature plays a direct role in determining the climate of every region. Temperature differences are also key in driving the global atmospheric circulation. Warm air tends to rise because it is light, while cold air tends to sink because it is dense, this sets the atmosphere in motion. The tropical circulation is a good example of this. In addition to understanding how temperature affects the atmospheric circulation, we also need to understand one of the basic forces governing air and water motion on earth: The Coriolis Force. But to understand this effect, we first need to review the concept of angular momentum conservation. Angular momentum conservation means that if a rotating object moves closer to its axis of rotation, it must speed up to conserve angular momentum. -
CHAPTER 3 Transport and Dispersion of Air Pollution
CHAPTER 3 Transport and Dispersion of Air Pollution Lesson Goal Demonstrate an understanding of the meteorological factors that influence wind and turbulence, the relationship of air current stability, and the effect of each of these factors on air pollution transport and dispersion; understand the role of topography and its influence on air pollution, by successfully completing the review questions at the end of the chapter. Lesson Objectives 1. Describe the various methods of air pollution transport and dispersion. 2. Explain how dispersion modeling is used in Air Quality Management (AQM). 3. Identify the four major meteorological factors that affect pollution dispersion. 4. Identify three types of atmospheric stability. 5. Distinguish between two types of turbulence and indicate the cause of each. 6. Identify the four types of topographical features that commonly affect pollutant dispersion. Recommended Reading: Godish, Thad, “The Atmosphere,” “Atmospheric Pollutants,” “Dispersion,” and “Atmospheric Effects,” Air Quality, 3rd Edition, New York: Lewis, 1997, pp. 1-22, 23-70, 71-92, and 93-136. Transport and Dispersion of Air Pollution References Bowne, N.E., “Atmospheric Dispersion,” S. Calvert and H. Englund (Eds.), Handbook of Air Pollution Technology, New York: John Wiley & Sons, Inc., 1984, pp. 859-893. Briggs, G.A. Plume Rise, Washington, D.C.: AEC Critical Review Series, 1969. Byers, H.R., General Meteorology, New York: McGraw-Hill Publishers, 1956. Dobbins, R.A., Atmospheric Motion and Air Pollution, New York: John Wiley & Sons, 1979. Donn, W.L., Meteorology, New York: McGraw-Hill Publishers, 1975. Godish, Thad, Air Quality, New York: Academic Press, 1997, p. 72. Hewson, E. Wendell, “Meteorological Measurements,” A.C. -
Chapter 7 100 Years of the Ocean General Circulation
CHAPTER 7 WUNSCH AND FERRARI 7.1 Chapter 7 100 Years of the Ocean General Circulation CARL WUNSCH Massachusetts Institute of Technology, and Harvard University, Cambridge, Massachusetts RAFFAELE FERRARI Massachusetts Institute of Technology, Cambridge, Massachusetts ABSTRACT The central change in understanding of the ocean circulation during the past 100 years has been its emergence as an intensely time-dependent, effectively turbulent and wave-dominated, flow. Early technol- ogies for making the difficult observations were adequate only to depict large-scale, quasi-steady flows. With the electronic revolution of the past 501 years, the emergence of geophysical fluid dynamics, the strongly inhomogeneous time-dependent nature of oceanic circulation physics finally emerged. Mesoscale (balanced), submesoscale oceanic eddies at 100-km horizontal scales and shorter, and internal waves are now known to be central to much of the behavior of the system. Ocean circulation is now recognized to involve both eddies and larger-scale flows with dominant elements and their interactions varying among the classical gyres, the boundary current regions, the Southern Ocean, and the tropics. 1. Introduction physical regimes, understanding of the ocean until relatively recently greatly lagged that of the atmo- In the past 100 years, understanding of the general sphere. As in almost all of fluid dynamics, progress circulation of the ocean has shifted from treating it as an in understanding has required an intimate partnership essentially laminar, steady-state, slow, almost geological, between theoretical description and observational or flow, to that of a perpetually changing fluid, best charac- laboratory tests. The basic feature of the fluid dynamics terized as intensely turbulent with kinetic energy domi- of the ocean, as opposed to that of the atmosphere, has nated by time-varying flows.