Copyright © 2013 Pearson Education, Inc. The Atmosphere: An Introduction to Meteorology, 12 th...

Copyright © 2013 Pearson Education, Inc.

The Atmosphere: An Introduction to Meteorology, 12th

Lutgens • Tarbuck

Lectures by:Heather Gallacher,Cleveland State University

Chapter 1: Introduction to the Atmosphere



Focus on the AtmosphereFocus on the Atmosphere

Weather in the United States:The weather in the U.S. varies greatly.Weather influences our daily lives.



Meteorology, Weather, and Climate:Meteorology

Study of atmosphere

Weather State of atmosphere at any given time & place

Climate “Average weather” Generalized weather variation for a given place Climate data can not predict weather.



Meteorology, Weather, and Climate



Weather and Climate: Weather and climate are expressed in the same elements.

Air temperature Air humidity Type and amount of clouds Type and amount of precipitation Air pressure Speed and direction of wind


Atmospheric Atmospheric HazardsHazards: : Assault by the ElementsAssault by the Elements

Lightning

Thunderstorms

Hurricanes

Cold waves

Tornadoes

Blizzards

Heat waves

Fog


Atmospheric Atmospheric HazardsHazards: : Assault by the ElementsAssault by the Elements


The Nature of Scientific InquiryThe Nature of Scientific Inquiry

Scientific inquiry is a collection of facts, observations, or measurements.Hypothesis:

Explanation of facts Test

Theory: Hypothesis that has passed many tests


The Nature of Scientific InquiryThe Nature of Scientific Inquiry

Scientific Methods:Are not recipes Involve creativity and insightRaise questionsCollect data Raise questions leading to hypothesesCause hypotheses to be accepted or rejectedCreate results shared with the scientific community for

further testing


Earth’s SpheresEarth’s Spheres



The Earth is made up of four spheres.GeosphereAtmosphereHydrosphereBiosphere

All the spheres are intertwined.Soil is part of all 4 spheres.



Geosphere:The geosphere consists of the solid Earth. It extends from the surface to the center, which is

approximately 6400 km.



Atmosphere:99% of the atmosphere is within 30 km of Earth’s surface. It protects the Earth.Weather occurs in the atmosphere.Without the atmosphere our planet would be lifeless like

the Moon. The surface of the Moon has not changed in nearly 3 billion years.



Hydrosphere:Oceans make up 71% the Earth’s surface.Additional parts of the hydrosphere:

Lakes Rivers, streams Glaciers Underground water



Biosphere:The biosphere includes all life on Earth.

On the ocean floor In boiling hot springs On air currents in the lower atmosphere


Earth as a SystemEarth as a System

Earth system science:Scientists have recognized they must learn how the

Earth’s individual components (land, water, air, and life-forms) are interconnected.

System:A system is a group of interacting or interdependent parts

that form a complex whole.


Composition of the AtmosphereComposition of the Atmosphere

Major components:The composition varies

from time to time. Oxygen and nitrogen

make up 99% of the volume.



Carbon dioxide:0.0391% of atmosphereAbsorbs energyPart of the carbon cycle



Variable components:Water vapor

0–4% by volume Clouds and precipitation

Aerosols Very small solid and liquid particles like dust, soot, sea salts Absorb radiation Cause cloud formation and red/orange sunrises and sunsets



Variable components:Ozone (O3)

There is much less ozone in the lower atmosphere. At higher altitudes (10–50 km), ozone absorbs UV radiation.


Ozone DepletionOzone Depletion——A Global IssueA Global Issue

Chlorofluorocarbons (CFCs): CFCs break down ozone in the upper atmosphere.CFCs are common in refrigerants and aerosol products.



The Antarctic ozone hole



Effects of ozone depletion: It causes more UV radiation to reach the surface.

UV radiation is known to cause cancer. It impacts the human immune system. UV radiation can also promote cataracts.



Montreal Protocol: It was concluded under the auspices of the UN in late

1987.190 nations eventually ratified the treaty.The protocol created legal controls on production and

consumption of ozone-depleting chemicals.


Vertical Structure of the AtmosphereVertical Structure of the Atmosphere


Vertical Structure of the AtmosphereVertical Structure of the Atmosphere

Pressure changes:An increased altitude decreases pressure.

Temperature changes: Increasing altitude causes a decreased temperature in the

troposphere.


Vertical Variations in CompositionVertical Variations in Composition

Homosphere:Lower layer, < 80 kmRoughly the same proportion of component gases

Heterosphere:Uppermost layer, > 80 kmOccurs in shells

Lower shell—N2

Next shell—O2

Next shell—He Outermost shell—H



Ionosphere:The ionosphere is located 80–400 km above the Earth’s

surface.At this altitude, atoms of oxygen and nitrogen become

ionized and absorb shortwave solar energy.



Troposphere:Temperature decreases with altitude.

Environmental lapse rate 6.5° C/km (variable)

The tropopause marks the top and the lowest temperature.

Stratosphere:Temperature increases with altitude.The ozone layer is concentrated in the stratosphere.The stratopause marks the top and the highest

temperature.



Mesosphere:Temperature decreases with altitude.The mesopause marks the top and its lowest temperature.

Thermosphere:The thermosphere has no well-defined upper limit.Temperature rises.There are 3 layers of varying ion density, D, E, and F.



Auroras:Aurora borealis (northern hemisphere)Aurora australis (southern hemisphere)

Occur in the ionosphere

Earth’s magnetic field traps solar particles.Auroras emit light.


End Chapter 1End Chapter 1

Copyright © 2013 Pearson Education, Inc. The Atmosphere: An Introduction to Meteorology, 12 th...

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