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On the Relationship Between Gravity Waves and Tropopause Height and Temperature Over the Globe Revealed by COSMIC Radio Occultation Measurements
atmosphere Article On the Relationship between Gravity Waves and Tropopause Height and Temperature over the Globe Revealed by COSMIC Radio Occultation Measurements Daocheng Yu 1, Xiaohua Xu 1,2,*, Jia Luo 1,3,* and Juan Li 1 1 School of Geodesy and Geomatics, Wuhan University, 129 Luoyu Road, Wuhan 430079, China; [email protected] (D.Y.); [email protected] (J.L.) 2 Collaborative Innovation Center for Geospatial Technology, 129 Luoyu Road, Wuhan 430079, China 3 Key Laboratory of Geospace Environment and Geodesy, Ministry of Education, 129 Luoyu Road, Wuhan 430079, China * Correspondence: [email protected] (X.X.); [email protected] (J.L.); Tel.: +86-27-68758520 (X.X.); +86-27-68778531 (J.L.) Received: 4 January 2019; Accepted: 6 February 2019; Published: 12 February 2019 Abstract: In this study, the relationship between gravity wave (GW) potential energy (Ep) and the tropopause height and temperature over the globe was investigated using COSMIC radio occultation (RO) dry temperature profiles during September 2006 to May 2013. The monthly means of GW Ep with a vertical resolution of 1 km and tropopause parameters were calculated for each 5◦ × 5◦ longitude-latitude grid. The correlation coefficients between Ep values at different altitudes and the tropopause height and temperature were calculated accordingly in each grid. It was found that at middle and high latitudes, GW Ep over the altitude range from lapse rate tropopause (LRT) to several km above had a significantly positive/negative correlation with LRT height (LRT-H)/ LRT temperature (LRT-T) and the peak correlation coefficients were determined over the altitudes of 10–14 km with distinct zonal distribution characteristics. -
Stratosphere-Troposphere Coupling: a Method to Diagnose Sources of Annular Mode Timescales
STRATOSPHERE-TROPOSPHERE COUPLING: A METHOD TO DIAGNOSE SOURCES OF ANNULAR MODE TIMESCALES Lawrence Mudryklevel, Paul Kushner p R ! ! SPARC DynVar level, Z(x,p,t)=− T (x,p,t)d ln p , (4) g !ps x,t p ( ) R ! ! Z(x,p,t)=− T (x,p,t)d ln p , (4) where p is the pressure at the surface, R is the specific gas constant and g is the gravitational acceleration s g !ps(x,t) where p is the pressure at theat surface, the surface.R is the specific gas constant and g is the gravitational acceleration Abstract s Geopotentiallevel, Height Decomposition Separation of AM Timescales p R ! ! at the surface. This time-varying geopotentialZ( canx,p,t be)= decomposed− T into(x,p a,t cli)dmatologyln p , and anomalies from the(4) climatology AM timescales track seasonal variations in the AM index’s decorrelation time6,7. For a hydrostatic fluid, geopotential height may be describedg !p sas(x ,ta) function of time, pressure level Timescales derived from Annular Mode (AM) variability provide dynamical and ashorizontalZ(x,p,t position)=Z (asx,p a )+temperatureδZ(x,p,t integral). Decomposing from the Earth’s the temperature surface to a andgiven surface pressure pressure fields inananalogous insight into stratosphere-troposphere coupling and are linked to the strengthThis of time-varying level, geopotentialwhere can beps is decomposed the pressure at into the a surface, climatologyR is the and specific anomalies gas constant from and theg is climatology the gravitational acceleration NCEP, 1958-2007 level: ^ a) o (yL ) d) o AM responses to climate forcings. -
Popular Summary of “Extratropical Stratosphere-Troposphere Mass Exchange”
Popular Summary of “Extratropical Stratosphere-Troposphere Mass Exchange” Mark Schoeberl Understanding the exchange of gases between the stratosphere and the troposphere is important for determining how pollutants enter the stratosphere and how they leave. This study does a global analysis of that the exchange of mass between the stratosphere and the troposphere. While the exchange of mass is not the same as the exchange of constituents, you can’t get the constituent exchange right if you have the mass exchange wrong. Thus this kind of calculation is an important test for models which also compute trace gas transport. In this study I computed the mass exchange for two assimilated data sets and a GCM. The models all agree that amount of mass descending from the stratosphere to the troposphere in the Northern Hemisphere extra tropics is -1 0” kg/s averaged over a year. The value for the Southern Hemisphere by about a factor of two. ( 10” kg of air is the amount of air in 100 km x 100 km area with a depth of 100 m - roughly the size of the D.C. metro area to a depth of 300 feet.) Most people have the idea that most of the mass enters the stratosphere through the tropics. But this study shows that almost 5 times more mass enters the stratosphere through the extra-tropics. This mass, however, is quickly recycled out again. Thus the lower most stratosphere is a mixture of upper stratospheric air and tropospheric air. This is an important result for understanding the chemistry of the lower stratosphere. -
Link Between the Double-Intertropical Convergence Zone Problem and Cloud Biases Over the Southern Ocean
Link between the double-Intertropical Convergence Zone problem and cloud biases over the Southern Ocean Yen-Ting Hwang1 and Dargan M. W. Frierson Department of Atmospheric Sciences, University of Washington, Seattle, WA 98195-1640 Edited by Mark H. Thiemens, University of California at San Diego, La Jolla, CA, and approved February 15, 2013 (received for review August 2, 2012) The double-Intertropical Convergence Zone (ITCZ) problem, in which climate models show that the bias can be reduced by changing excessive precipitation is produced in the Southern Hemisphere aspects of the convection scheme (e.g., refs. 7–9) or changing the tropics, which resembles a Southern Hemisphere counterpart to the surface wind stress formulation (e.g., ref. 10). Given the complex strong Northern Hemisphere ITCZ, is perhaps the most significant feedback processes in the tropics, it is challenging to understand and most persistent bias of global climate models. In this study, we the mechanisms by which the sensitivity experiments listed above look to the extratropics for possible causes of the double-ITCZ improve tropical precipitation. problem by performing a global energetic analysis with historical Recent work in general circulation theory has suggested that simulations from a suite of global climate models and comparing one should not only look within the tropics for features that affect with satellite observations of the Earth’s energy budget. Our results tropical precipitation. A set of idealized experiments showed that show that models with more energy flux into the Southern heating a global climate model exclusively in the extratropics can Hemisphere atmosphere (at the top of the atmosphere and at the lead to tropical rainfall shifts from one side of the tropics to the surface) tend to have a stronger double-ITCZ bias, consistent with other (11). -
The Tropical Tropopause Layer in Reanalysis Data Sets
https://doi.org/10.5194/acp-2019-580 Preprint. Discussion started: 4 July 2019 c Author(s) 2019. CC BY 4.0 License. 1 2 The tropical tropopause layer in reanalysis data sets 3 4 Susann Tegtmeier1, James Anstey2, Sean Davis3, Rossana Dragani4, Yayoi Harada5, Ioana 5 Ivanciu1, Robin Pilch Kedzierski1, Kirstin Krüger6, Bernard Legras7, Craig Long8, James S. 6 Wang9, Krzysztof Wargan10,11, and Jonathon S. Wright12 7 8 9 1 10 GEOMAR Helmholtz Centre for Ocean Research Kiel, 24105 Kiel, Germany 11 2Canadian Centre for Climate Modelling and Analysis, ECCC, Victoria, Canada 12 3Earth System Research Laboratory, National Oceanic and Atmospheric Administration, 13 Boulder, CO 80305, USA 14 4European Centre for Medium-Range Weather Forecasts, Reading, RG2 9AX, UK 15 5Japan Meteorological Agency, Tokyo, 100-8122, Japan 16 6 Section for Meteorology and Oceanography, Department of Geosciences, University of Oslo, 17 0315 Oslo, Norway 18 7Laboratoire de Météorologie Dynamique, CNRS/PSL-ENS, Sorbonne University Ecole 19 Polytechnique, France 20 8Climate Prediction Center, National Centers for Environmental Prediction, National Oceanic 21 and Atmospheric Administration, College Park, MD 20740, USA 22 9Institute for Advanced Sustainability Studies, Potsdam, Germany 23 10Science Systems and Applications, Inc., Lanham, MD 20706, USA 24 11Global Modeling and Assimilation Office, Code 610.1, NASA Goddard Space Flight 25 Center, Greenbelt, MD 20771, USA 26 12Department of Earth System Science, Tsinghua University, Beijing, 100084, China 27 28 29 30 31 32 33 34 35 36 37 1 https://doi.org/10.5194/acp-2019-580 Preprint. Discussion started: 4 July 2019 c Author(s) 2019. CC BY 4.0 License. -
Tropical Weather Discussion
TROPICAL WEATHER DISCUSSION • Purpose The Tropical Weather Discussion describes major synoptic weather features and significant areas of disturbed weather in the tropics. The product is intended to provide current weather information for those who need to know the current state of the atmosphere and expected trends to assist them in their decision making. The product gives significant weather features, areas of disturbed weather, expected trends, the meteorological reasoning behind the forecast, model performance, and in some cases a degree of confidence. • Content The Tropical Weather Discussion is a narrative explaining the current weather conditions across the tropics and the expected short-term changes. The product is divided into four different sections as outline below: 1. SPECIAL FEATURES (event-driven) The special features section includes descriptions of hurricanes, tropical storms, tropical depressions, subtropical cyclones, and any other feature of significance that may develop into a tropical or subtropical cyclone. For active tropical cyclones, this section provides the latest advisory data on the system. Associated middle and upper level interactions as well as significant clouds and convection are discussed with each system. This section is omitted if none of these features is present. 2. TROPICAL WAVES (event-driven) This section provides a description of the strength, position, and movement of all tropical waves analyzed on the surface analysis, from east to west. A brief reason for a wave’s position is usually given, citing surface observations, upper air time sections, satellite imagery, etc. The associated convection is discussed with each tropical wave as well as any potential impacts to landmasses or marine interests. -
Extratropical Cyclones and Anticyclones
© Jones & Bartlett Learning, LLC. NOT FOR SALE OR DISTRIBUTION Courtesy of Jeff Schmaltz, the MODIS Rapid Response Team at NASA GSFC/NASA Extratropical Cyclones 10 and Anticyclones CHAPTER OUTLINE INTRODUCTION A TIME AND PLACE OF TRAGEDY A LiFE CYCLE OF GROWTH AND DEATH DAY 1: BIRTH OF AN EXTRATROPICAL CYCLONE ■■ Typical Extratropical Cyclone Paths DaY 2: WiTH THE FI TZ ■■ Portrait of the Cyclone as a Young Adult ■■ Cyclones and Fronts: On the Ground ■■ Cyclones and Fronts: In the Sky ■■ Back with the Fitz: A Fateful Course Correction ■■ Cyclones and Jet Streams 298 9781284027372_CH10_0298.indd 298 8/10/13 5:00 PM © Jones & Bartlett Learning, LLC. NOT FOR SALE OR DISTRIBUTION Introduction 299 DaY 3: THE MaTURE CYCLONE ■■ Bittersweet Badge of Adulthood: The Occlusion Process ■■ Hurricane West Wind ■■ One of the Worst . ■■ “Nosedive” DaY 4 (AND BEYOND): DEATH ■■ The Cyclone ■■ The Fitzgerald ■■ The Sailors THE EXTRATROPICAL ANTICYCLONE HIGH PRESSURE, HiGH HEAT: THE DEADLY EUROPEAN HEAT WaVE OF 2003 PUTTING IT ALL TOGETHER ■■ Summary ■■ Key Terms ■■ Review Questions ■■ Observation Activities AFTER COMPLETING THIS CHAPTER, YOU SHOULD BE ABLE TO: • Describe the different life-cycle stages in the Norwegian model of the extratropical cyclone, identifying the stages when the cyclone possesses cold, warm, and occluded fronts and life-threatening conditions • Explain the relationship between a surface cyclone and winds at the jet-stream level and how the two interact to intensify the cyclone • Differentiate between extratropical cyclones and anticyclones in terms of their birthplaces, life cycles, relationships to air masses and jet-stream winds, threats to life and property, and their appearance on satellite images INTRODUCTION What do you see in the diagram to the right: a vase or two faces? This classic psychology experiment exploits our amazing ability to recognize visual patterns. -
11 General Circulation
Copyright © 2017 by Roland Stull. Practical Meteorology: An Algebra-based Survey of Atmospheric Science. v1.02 “Practical Meteorology: An Algebra-based Survey of Atmospheric Science” by Roland Stull is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. View this license at http://creativecommons.org/licenses/by- nc-sa/4.0/ . This work is available at https://www.eoas.ubc.ca/books/Practical_Meteorology/ 11 GENERAL CIRCULATION Contents A spatial imbalance between radiative inputs and outputs exists for the earth-ocean-atmosphere 11.1. Key Terms 330 system. The earth loses energy at all latitudes due 11.2. A Simple Description of the Global Circulation 330 to outgoing infrared (IR) radiation. Near the trop- 11.2.1. Near the Surface 330 ics, more solar radiation enters than IR leaves, hence 11.2.2. Upper-troposphere 331 there is a net input of radiative energy. Near Earth’s 11.2.3. Vertical Circulations 332 poles, incoming solar radiation is too weak to totally 11.2.4. Monsoonal Circulations 333 offset the IR cooling, allowing a net loss of energy. 11.3. Radiative Differential Heating 334 The result is differential heating, creating warm 11.3.1. North-South Temperature Gradient 335 equatorial air and cold polar air (Fig. 11.1a). 11.3.2. Global Radiation Budgets 336 This imbalance drives the global-scale general 11.3.3. Radiative Forcing by Latitude Belt 338 circulation of winds. Such a circulation is a fluid- 11.3.4. General Circulation Heat Transport 338 dynamical analogy to Le Chatelier’s Principle of 11.4. -
ESSENTIALS of METEOROLOGY (7Th Ed.) GLOSSARY
ESSENTIALS OF METEOROLOGY (7th ed.) GLOSSARY Chapter 1 Aerosols Tiny suspended solid particles (dust, smoke, etc.) or liquid droplets that enter the atmosphere from either natural or human (anthropogenic) sources, such as the burning of fossil fuels. Sulfur-containing fossil fuels, such as coal, produce sulfate aerosols. Air density The ratio of the mass of a substance to the volume occupied by it. Air density is usually expressed as g/cm3 or kg/m3. Also See Density. Air pressure The pressure exerted by the mass of air above a given point, usually expressed in millibars (mb), inches of (atmospheric mercury (Hg) or in hectopascals (hPa). pressure) Atmosphere The envelope of gases that surround a planet and are held to it by the planet's gravitational attraction. The earth's atmosphere is mainly nitrogen and oxygen. Carbon dioxide (CO2) A colorless, odorless gas whose concentration is about 0.039 percent (390 ppm) in a volume of air near sea level. It is a selective absorber of infrared radiation and, consequently, it is important in the earth's atmospheric greenhouse effect. Solid CO2 is called dry ice. Climate The accumulation of daily and seasonal weather events over a long period of time. Front The transition zone between two distinct air masses. Hurricane A tropical cyclone having winds in excess of 64 knots (74 mi/hr). Ionosphere An electrified region of the upper atmosphere where fairly large concentrations of ions and free electrons exist. Lapse rate The rate at which an atmospheric variable (usually temperature) decreases with height. (See Environmental lapse rate.) Mesosphere The atmospheric layer between the stratosphere and the thermosphere. -
On the Impact of Future Climate Change on Tropopause Folds and Tropospheric Ozone
https://doi.org/10.5194/acp-2019-508 Preprint. Discussion started: 14 June 2019 c Author(s) 2019. CC BY 4.0 License. On the impact of future climate change on tropopause folds and tropospheric ozone Dimitris Akritidis1, Andrea Pozzer2, and Prodromos Zanis1 1Department of Meteorology and Climatology, School of Geology, Aristotle University of Thessaloniki, Thessaloniki, Greece 2Max Planck Institute for Chemistry, Mainz, Germany Correspondence: D. Akritidis ([email protected]) Abstract. Using a transient simulation for the period 1960-2100 with the state-of-the-art ECHAM5/MESSy Atmospheric Chemistry (EMAC) global model and a tropopause fold identification algorithm, we explore the future projected changes in tropopause folds, Stratosphere-to-Troposphere Transport (STT) of ozone and tropospheric ozone under the RCP6.0 scenario. Statistically significant changes in tropopause fold frequencies are identified in both Hemispheres, occasionally exceeding 3%, 5 which are associated with the projected changes in the position and intensity of the subtropical jet streams. A strengthen- ing of ozone STT is projected for future at both Hemispheres, with an induced increase of transported stratospheric ozone tracer throughout the whole troposphere, reaching up to 10 nmol/mol in the upper troposphere, 8 nmol/mol in the middle troposphere and 3 nmol/mol near the surface. Notably, the regions exhibiting the maxima changes of ozone STT at 400 hPa, coincide with that of the highest fold frequencies, highlighting the role of tropopause folding mechanism in STT process under 10 a changing climate. For both the eastern Mediterranean and Middle East (EMME), and the Afghanistan (AFG) regions, which are known as hotspots of fold activity and ozone STT during the summer period, the year-to-year variability of middle tropo- spheric ozone with stratospheric origin is largely explained by the short-term variations of ozone at 150 hPa and tropopause folds frequency. -
Ozone: Good up High, Bad Nearby
actions you can take High-Altitude “Good” Ozone Ground-Level “Bad” Ozone •Protect yourself against sunburn. When the UV Index is •Check the air quality forecast in your area. At times when the Air “high” or “very high”: Limit outdoor activities between 10 Quality Index (AQI) is forecast to be unhealthy, limit physical exertion am and 4 pm, when the sun is most intense. Twenty minutes outdoors. In many places, ozone peaks in mid-afternoon to early before going outside, liberally apply a broad-spectrum evening. Change the time of day of strenuous outdoor activity to avoid sunscreen with a Sun Protection Factor (SPF) of at least 15. these hours, or reduce the intensity of the activity. For AQI forecasts, Reapply every two hours or after swimming or sweating. For check your local media reports or visit: www.epa.gov/airnow UV Index forecasts, check local media reports or visit: www.epa.gov/sunwise/uvindex.html •Help your local electric utilities reduce ozone air pollution by conserving energy at home and the office. Consider setting your •Use approved refrigerants in air conditioning and thermostat a little higher in the summer. Participate in your local refrigeration equipment. Make sure technicians that work on utilities’ load-sharing and energy conservation programs. your car or home air conditioners or refrigerator are certified to recover the refrigerant. Repair leaky air conditioning units •Reduce air pollution from cars, trucks, gas-powered lawn and garden before refilling them. equipment, boats and other engines by keeping equipment properly tuned and maintained. During the summer, fill your gas tank during the cooler evening hours and be careful not to spill gasoline. -
Migration and Climate Change
Migration and Climate Change No. 31 The opinions expressed in the report are those of the authors and do not necessarily reflect the views of the International Organization for Migration (IOM). The designations employed and the presentation of material throughout the report do not imply the expression of any opinion whatsoever on the part of IOM concerning the legal status of any country, territory, city or area, or of its authorities, or concerning its frontiers or boundaries. _______________ IOM is committed to the principle that humane and orderly migration benefits migrants and society. As an intergovernmental organization, IOM acts with its partners in the international community to: assist in meeting the operational challenges of migration; advance understanding of migration issues; encourage social and economic development through migration; and uphold the human dignity and well-being of migrants. _______________ Publisher: International Organization for Migration 17 route des Morillons 1211 Geneva 19 Switzerland Tel: +41.22.717 91 11 Fax: +41.22.798 61 50 E-mail: [email protected] Internet: http://www.iom.int Copy Editor: Ilse Pinto-Dobernig _______________ ISSN 1607-338X © 2008 International Organization for Migration (IOM) _______________ All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise without the prior written permission of the publisher. 11_08 Migration and Climate Change1 Prepared for IOM by Oli Brown2 International Organization for Migration Geneva CONTENTS Abbreviations 5 Acknowledgements 7 Executive Summary 9 1. Introduction 11 A growing crisis 11 200 million climate migrants by 2050? 11 A complex, unpredictable relationship 12 Refugee or migrant? 1 2.