The Response of Subtropical Highs to Climate Change
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Responses of the Hydrological Cycle to Solar Forcings
1 Responses of the hydrological cycle to solar forcings Jane Smyth Advised by Dr. Trude Storelvmo Second Reader Dr. William Boos May 6, 2016 A Senior Thesis presented to the faculty of the Department of Geology and Geophysics, Yale University, in partial fulfillment of the Bachelor’s Degree. In presenting this thesis in partial fulfillment of the Bachelor’s Degree from the Department of Geology and Geophysics, Yale University, I agree that the department may make copies or post it on the departmental website so that others may better understand the undergraduate research of the de- partment. I further agree that extensive copying of this thesis is allowable only for scholarly purposes. It is understood, however, that any copying or publication of this thesis for commercial purposes or financial gain is not allowed without my written consent. Jane Elizabeth Smyth, 6 May, 2016 RESPONSESOFTHE HYDROLOGICALCYCLETOjane smyth SOLARFORCINGS Senior Thesis advised by dr. trude storelvmo 1 Chapter I: Solar Geoengineering 4 contents1.1 Abstract . 4 1.2 Introduction . 5 1.2.1 Solar Geoengineering . 5 1.2.2 The Hydrological Cycle . 5 1.3 Models & Methods . 7 1.4 Results and Discussion . 9 1.4.1 Thermodynamic Scaling of Net Precipitation . 9 1.4.2 Dynamically Driven Precipitation . 12 1.4.3 Relative Humidity . 12 1.5 Conclusions . 14 1.6 Appendix . 16 2 Chapter II: Orbital Precession 22 2.1 Abstract . 22 2.2 Introduction . 23 2.3 Experimental Design & Methods . 24 2.3.1 Atmospheric Heat Transport . 25 2.3.2 Hadley Circulation . 25 2.3.3 Gross Moist Stability . -
Hadley Cell and the Trade Winds of Hawai'i: Nā Makani
November 19, 2012 Hadley Cell and the Trade Winds of Hawai'i Hadley Cell and the Trade Winds of Hawai‘i: Nā Makani Mau Steven Businger & Sara da Silva [email protected], [email protected] Iasona Ellinwood, [email protected] Pauline W. U. Chinn, [email protected] University of Hawai‘i at Mānoa Figure 1. Schematic of global circulation Grades: 6-8, modifiable for 9-12 Time: 2 - 10 hours Nā Honua Mauli Ola, Guidelines for Educators, No Nā Kumu: Educators are able to sustain respect for the integrity of one’s own cultural knowledge and provide meaningful opportunities to make new connections among other knowledge systems (p. 37). Standard: Earth and Space Science 2.D ESS2D: Weather and Climate Weather varies day to day and seasonally; it is the condition of the atmosphere at a given place and time. Climate is the range of a region’s weather over one to many years. Both are shaped by complex interactions involving sunlight, ocean, atmosphere, latitude, altitude, ice, living things, and geography that can drive changes over multiple time scales—days, weeks, and months for weather to years, decades, centuries, and beyond for climate. The ocean absorbs and stores large amounts of energy from the sun and releases it slowly, moderating and stabilizing global climates. Sunlight heats the land more rapidly. Heat energy is redistributed through ocean currents and atmospheric circulation, winds. Greenhouse gases absorb and retain the energy radiated from land and ocean surfaces, regulating temperatures and keep Earth habitable. (A Framework for K-12 Science Education, NRC, 2012) Hawai‘i Content and Performance Standards (HCPS) III http://standardstoolkit.k12.hi.us/index.html 1 November 19, 2012 Hadley Cell and the Trade Winds of Hawai'i STRAND THE SCIENTIFIC PROCESS Standard 1: The Scientific Process: SCIENTIFIC INVESTIGATION: Discover, invent, and investigate using the skills necessary to engage in the scientific process Benchmarks: SC.8.1.1 Determine the link(s) between evidence and the Topic: Scientific Inquiry conclusion(s) of an investigation. -
WX Rules: Avoiding the Azores High
BLUEWATER SAILING 2012 ARC EUROPE from Wild Goose on banjo, who teamed up with John Simpson (guitar and trumpet) and Mikaela Meik (vio- lin) from the British Warrior 40 Chis- cos, plus Andrew Siess, crew from Outer Limits (also on violin). John, a retail executive on sabbati- cal, told me he’d been performing in pickup groups with other sailors throughout his cruise across the Atlan- tic and back. “The name of the band is Linda and Hugh Moore aboard Wild Goose in mid-ocean (left); they celebrated their 25th wedding always Sailing Together,” he explained. anniversary while on passage together. David Leyland aboard First Edition III in Bermuda (right) “As in people ask what the band’s name is, and I say, ‘I don’t know. We’ve when she struck what is believed to tiently while Joost and crew boarded just been sailing together.’” have been a whale late at night and a 36,000-ton container ship bound for The start out of Bermuda on May 16 started taking on water. Joost hoped Italy as Outer Limits started sinking was spectacular, with all the fleet his pumps could keep the boat afloat beneath the waves. But it was among streaming out Town Cut at St. Georg- long enough to get back to Bermuda, the Hampton boats, particularly on es under sail together. But soon but soon he called for an evacuation. Wild Goose, that the loss was most enough the group from Hampton felt It was one of the Tortola boats, Halo, a acutely felt. fate pressing them again. -
The International Journal of Meteorology
© THE INTERNATIONAL JOURNAL OF METEOROLOGY © THE INTERNATIONAL JOURNAL OF METEOROLOGY 136 April 2006, Vol.31, No.308 April 2006, Vol.31, No.308 133 THE INTERNATIONAL JOURNAL OF METEOROLOGY “An international magazine for everyone interested in weather and climate, and in their influence on the human and physical environment.” HEAT WAVE OVER EGYPT DURING THE SUMMER OF 1998 By H. ABDEL BASSET1 and H. M. HASANEN2 1Department of Astronomy and Meteorology, Faculty of Science, Al-Azhar University, Cairo, Egypt. 2Department of Astronomy and Meteorology, Faculty of Science, Cairo University, Cairo, Egypt. Fig. 2: as in Fig. 1 but for August. Abstract: During the summer of 1998, the Mediterranean area is subject to episodes of air temperature increase, which are usually referred to as “heat waves”. These waves are characterised by a long lasting duration and pronounced intensity of the temperature anomaly. A diagnostic study is carried out to TEMPERATURE analyse and investigate the causes of this summer heat wave, NCEP/NCAR reanalysis data are used in this Fig. 3 illustrates the distribution of the average July (1960-2000) temperature and its study. The increase of temperature during the summer of 1998 is shown to be due to the increase of the differences from July 1998 at the mean sea level pressure and 500 hPa. Fig. 3a shows that subsidence of: 1) the branch of the local tropical Northern Hemisphere Hadley cell; 2) the branch of the the temperature increases from north to south and over the warmest area in our domain Walker type over the Mediterranean sea and North Africa; 3) the steady northerly winds between the Asiatic monsoon low and the Azores high pressure. -
Catastrophic Weather Perils in the United States Climate Drivers Catastrophic Weather Perils in the United States Climate Drivers
Catastrophic Weather Perils in the United States Climate Drivers Catastrophic Weather Perils in the United States Climate Drivers Table of Contents 2 Introduction 2 Atlantic Hurricanes –2 Formation –3 Climate Impacts •3 Atlantic Sea Surface Temperatures •4 El Niño Southern Oscillation (ENSO) •6 North Atlantic Oscillation (NAO) •7 Quasi-Biennial Oscillation (QBO) –Summary8 8 Severe Thunderstorms –8 Formation –9 Climate Impacts •9 El Niño Southern Oscillation (ENSO) 10• Pacific Decadal Oscillation (PDO) 10– Other Climate Impacts 10–Summary 11 Wild Fire 11– Formation 11– Climate Impacts 11• El Niño Southern Oscillation (ENSO) & Pacific Decadal Oscillation (PDO) 12– Other Climate / Weather Variables 12–Summary May 2012 The information contained in this document is strictly proprietary and confidential. 1 Catastrophic Weather Perils in the United States Climate Drivers INTRODUCTION The last 10 years have seen a variety of weather perils cause significant insured losses in the United States. From the wild fires of 2003, hurricanes of 2004 and 2005, to the severe thunderstorm events in 2011, extreme weather has the appearance of being the norm. The industry has experienced over $200B in combined losses from catastrophic weather events in the US since 2002. While the weather is often seen as a random, chaotic thing, there are relatively predictable patterns (so called “climate states”) in the weather which can be used to inform our expectations of extreme weather events. An oft quoted adage is that “climate is what you expect; weather is what you actually observe.” A more useful way to think about the relationship between weather and climate is that the climate is the mean state of the atmosphere (either locally or globally) which changes over time, and weather is the variation around that mean. -
Change of the Tropical Hadley Cell Since 1950
Change of the Tropical Hadley Cell Since 1950 Xiao-Wei Quan, Henry F. Diaz, and Martin P. Hoerling NOAA-CIRES Climate Diagnostic Center, Boulder, Colorado, USA last revision: March 24, 2004 Abstract The change in the tropical Hadley cell since 1950 is examined within the context of the long-term warming in the global surface temperatures. The study involves analyses of observations, including various metrics of Hadley cell, and ensemble 50-year simulations by an atmospheric general circulation model forced with the observed evolution of global sea surface temperature since 1950. Consistent evidence is found for an intensification of the Northern Hemisphere winter Hadley cell since 1950. This is shown to be an atmospheric response to the observed tropical ocean warming trend, together with an intensification in El Niño’s interannual fluctuations including larger amplitude and increased frequency after 1976. The intensification of the winter Hadley cell is shown to be associated with an intensified hydrological cycle consisting of increased equatorial oceanic rainfall, and a general drying of tropical/subtropical landmasses. This Hadley cell change is consistent with previously documented dynamic changes in the extratropics, including a strengthening of westerly atmospheric flow and an intensification of midlatitude cyclones. 1. Introduction The tropical Hadley cell, by definition, is the zonal mean meridional mass circulation in the atmosphere bounded roughly by 30ºS and 30ºN. It is characterized by equatorward mass transport by the prevailing trade wind flow in the lower troposphere, and poleward mass transport in the upper troposphere. This lateral mass circulation links the mean ascending motion in the equatorial zone with subsidence in the subtropics, and represents a major part of the large-scale meridional overturning between tropics and subtropics. -
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. -
Hadley's Principle: Understanding and Misunderstanding the Trade
History of Meteorology 3 (2006) 17 Hadley’s Principle: Understanding and Misunderstanding the Trade Winds Anders O. Persson Department for research and development Swedish Meteorological and Hydrological Institute SE 601 71 Norrköping, Sweden [email protected] Old knowledge will often be rediscovered and presented under new labels, causing much confusion and impeding progress—Tor Bergeron.1 Introduction In May 1735 a fairly unknown Englishman, George Hadley, published a groundbreaking paper, “On the Cause of the General Trade Winds,” in the Philosophical Transactions of the Royal Society. His path to fame was long and it took 100 years to have his ideas accepted by the scientific community. But today there is a “Hadley Crater” on the moon, the convectively overturning in the tropics is called “The Hadley Cell,” and the climatological centre of the UK Meteorological Office “The Hadley Centre.” By profession a lawyer, born in London, George Hadley (1685-1768) had in 1735 just became a member of the Royal Society. He was in charge of the Society’s meteorological work which consisted of providing instruments to foreign correspondents and of supervising, collecting and scrutinizing the continental network of meteorological observations2. This made him think about the variations in time and geographical location of the surface pressure and its relation to the winds3. Already in a paper, possibly written before 1735, Hadley carried out an interesting and far-sighted discussion on the winds, which he found “of so uncertain and variable nature”: Hadley’s Principle 18 …concerning the Cause of the Trade-Winds, that for the same Cause the Motion of the Air will not be naturally in a great Circle, for any great Space upon the surface of the Earth anywhere, unless in the Equator itself, but in some other Line, and, in general, all Winds, as they come nearer the Equator will become more easterly, and as they recede from it, more and more westerly, unless some other Cause intervene4. -
Atmospheric Circulation
Atmospheric circulation Trade winds http://science.nasa.gov/science-news/science-at-nasa/2002/10apr_hawaii/ Atmosphere (noun) the envelope of gases (air) surrounding the earth or another planet Dry air: Argon, 0.98% O2, 21% N2, 78% CO2, >400ppm & rising Water vapor can be up to 4% 50% below 5.6 km (18,000 ft) 90% below 16 km (52,000 ft) http://mychinaviews.com/2011/06/into-thin-air.html Drivers of atmospheric circulation Uneven solar heating At poles sun’s energy is spread over a larger region Uneven solar heating At poles sun’s energy is spread over a larger region Uneven solar heating At poles sun’s energy is spread over a larger region Ways to transfer heat Conduction: Transfer of heat by direct contact. Heat goes from warmer areas to colder areas. Ways to transfer heat Radiation: Any object radiates heat as electromagnetic radiation (light, infrared) based on temperature of the object. Ways to transfer heat Convection: Heat carried by a fluid (air, water, etc) from a region of high temperature to a region of lower temperature. Convection cell Warm air rises, then as it cools it sinks back down Thermal (heat) balance Heat in = Heat out, for earth as a whole ! Heat in = Heat out, for latitude bands " Heat out t r o p s n a r Heat in t t a e h t e N RedistributionIncreasing heat of heat drive atmospheric circulation So, might expect Cool air sinking near the poles Warm air rising at equator Lutgens and Tarbuk, 2001 http://www.ux1.eiu.edu/~cfjps/1400/circulation.html Turns out a 3 cell modelis better Polar cell Ferrel cell (Mid-latitude -
ESCI 344 – Tropical Meteorology Lesson 3 – General Circulation of the Tropics
ESCI 344 – Tropical Meteorology Lesson 3 – General Circulation of the Tropics References: Forecaster’s Guide to Tropical Meteorology (updated), Ramage Climate Dynamics of the Tropics, Hastenrath Tropical Climatology (2nd ed), McGregor and Nieuwolt Tropical Meteorology, Tarakanov Climate and Weather in the Tropics, Riehl General Circulation of the Tropical Atmosphere, Vol II, Newell et al. “The South Pacific Convergence Zone (SPCZ): A Review”, Vincent, Mon.Wea. Rev., 122, 1949-1970, 1994 “The Central Pacific Near-Equatorial Convergence Zone”, Ramage, J. Geophys. Res., 86, 6580-6598 Reading: Introduction to the Meteorology and Climate of the Tropics, Chapter 3 Vincent, “The SPCZ: A Review” Lau and Yang, “Walker Circulation” James, “Hadley Circulation” Waliser, “Intertropical Convergence Zones” Hastenrath, “Tropical Climates” Madden, “Intraseasonal Oscillation (MJO)” TERMINOLOGY Boreal refers to the Northern Hemisphere Austral refers to the Southern Hemisphere LATITUDINAL HEAT IMBALANCE Net radiation flux is defined as the difference in incoming radiation flux and outgoing radiation flux. A positive net radiation flux indicates a surplus of energy, while a negative net radiation flux indicates a deficit. This figure shows the longitudinally-averaged, annual-mean radiation fluxes at the top of the atmosphere. Outgoing shortwave is due to scattering and reflection. Net shortwave is the difference between the incoming and outgoing shortwave radiation. When the earth-atmosphere system is considered as a whole, there is a positive net radiation flux between about 40N and 40S, while there is a negative net radiation flux poleward of 40 in both hemispheres. In order for a steady-state temperature to be achieved, there must be transport of heat from the earth’s surface to the atmosphere, and from the tropics to the polar regions. -
Hadley Cell Expansion in CMIP6 Models Kevin M
https://doi.org/10.5194/acp-2019-1206 Preprint. Discussion started: 22 January 2020 c Author(s) 2020. CC BY 4.0 License. Hadley cell expansion in CMIP6 models Kevin M. Grise1, Sean M. Davis2 1Department of Environmental Sciences, University of Virginia, Charlottesville, VA 22904, USA 2NOAA Earth System Research Laboratory Chemical Sciences Division, Boulder, CO 80305 USA 5 Correspondence to: Kevin M. Grise ([email protected]) Abstract. In response to increasing greenhouse gases, the subtropical edges of Earth’s Hadley circulation shift poleWard in global climate models. Recent studies have found that reanalysis trends in the Hadley cell edge over the past 30–40 years are Within the range of trends simulated by Coupled Model Intercomparison Project Phase 5 (CMIP5) models, and have documented seasonal and hemispheric asymmetries in these trends. In this study, We evaluate Whether these conclusions 10 hold for the newest generation of models (CMIP6). Overall, We find similar characteristics of Hadley cell expansion in CMIP5 and CMIP6 models. In both CMIP5 and CMIP6 models, the poleward shift of the Hadley cell edge in response to increasing greenhouse gases is 2–3 times larger in the Southern Hemisphere (SH), except during September–November. The trends from CMIP5 and CMIP6 models agree Well With reanalyses, although prescribing observed coupled atmosphere- ocean variability allows the models to better capture reanalysis trends in the Northern Hemisphere (NH). We find tWo 15 notable differences betWeen CMIP5 and CMIP6 models. First, both CMIP5 and CMIP6 models contract the NH summertime Hadley circulation equatorward (particularly over the Pacific sector), but this contraction is larger in CMIP6 models due to their higher average climate sensitivity. -
The Impact of Convection in the West African Monsoon Region on Weather Forecasts in the North Atlantic-European Sector
Geophysical Research Abstracts Vol. 20, EGU2018-12545, 2018 EGU General Assembly 2018 © Author(s) 2018. CC Attribution 4.0 license. The impact of convection in the West African monsoon region on weather forecasts in the North Atlantic-European sector Gregor Pante and Peter Knippertz Karlsruhe Institute of Technology (KIT), Institute of Meteorology and Climate Research, Karlsruhe, Germany ([email protected]) The West African monsoon is the driving element of weather and climate during summer in the Sahel region. It interacts with mesoscale convective systems (MCSs) and the African easterly jet and African easterly waves. Poor representation of convection in numerical models, particularly its organisation on the mesoscale, can result in unrealistic forecasts of the monsoon dynamics. Arguably, the parameterisation of convection is one of the main deficiencies in models over this region. Overall, this has negative impacts on forecasts over West Africa itself but may also affect remote regions, as waves originating from convective heating are badly represented. Here we investigate those remote forecast impacts based on daily initialised 10-day forecasts for July 2016 using the ICON model. One type of simulations employs the default setup of the global model with a horizontal grid spacing of 13 km. It is compared with simulations using the 2-way nesting capability of ICON. A second model domain over West Africa (the nest) with 6.5 km grid spacing is sufficient to explicitly resolve MCSs in this region. In the 2-way nested simulations, the prognostic variables of the global model are influenced by the results of the nest through relaxation.