Marine Science 102: Introduction to Weather and Climate

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Marine Science 102 Introduction to Weather and
Climate Instructors Prof. Sharan Majumdar
(Section Q)smajumdar_at_rsmas.miami.eduandProf.
Brian Mapes (Section R)bmapes_at_rsmas.miami.eduTA
Mr David Painemaldpainemal_at_rsmas.miami.eduCou
rse Websiteshttp//metofis.rsmas.miami.edu/msc1
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Weather Map Links
http//www.hpc.ncep.noaa.gov weather
animations http//www.spc.noaa.gov storm
watches and warnings http//www.nhc.noaa.gov -
hurricanes
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• What are Weather and Climate?
• Weather is the condition of the atmosphere at a
  particular moment
• Precipitation, temperature, wind speed and
  direction, relative humidity, dewpoint, cloud
  cover,
• METEOROLOGY is the study of the science of
  weather.
• Climate is the condition of the atmosphere over
  many years
• Long-term averages of temperature, moisture,
  winds, clouds, precipitation,

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• Climate is what you expect, weather is what you
  get! Robert A. Heinlein
• Ed Lorenz (MIT) The Father of Chaos

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Syllabus

• Broken into 3 sections
• (i) Fundamentals (ii) Weather (iii) Climate
• Syllabus (subject to change)
• http//metofis.rsmas.miami.edu/msc102/schedule.ht
  ml

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Grades

• Exams (70)
• 3 exams (Feb 17, Mar 26, Apr 30)
• Short answers.
• No Final Exam.
• Quizzes (30)
• 6 Pop quizzes at beginning or end of class.
• Easy.

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Textbook
OR
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Rules

• Arrive on time.
• Cell phones, Laptops, iPhones etc off.
• No talking, txting, reading non-class material
• No copying in quizzes / exams.
• Deduction in grade for violations.

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Chapter One Composition and Structure of the
Atmosphere
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• Chapter 1 Outline
• Composition of the Atmosphere
• Physical Properties
• Composition
• Evolution of the Atmosphere
• Important Trace Gases
• Water vapor (H2O)
• Carbon Dioxide (CO2)
• Ozone (O3)
• Others Aerosols, Methane,
• Vertical Structure of the Atmosphere
• Pressure and Density
• Other Planetary Atmospheres

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Making an Atmosphere Gases and Gravity
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• Physical Properties
• A mixture of gas molecules and very small
  particles of solid and liquid.
• Behaves as a fluid!
• The majority of atmospheric mass is contained in
  a rather thin layer near the surface (99.9 is
  below 50 km).
• Compared with the radius of the Earth (6500 km),
  the atmosphere is very thin (50 km or 1).
• Atmospheric motions (winds) are largely
  horizontal rather than vertical.

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Composition of the Atmosphere
78 Nitrogen
20 Oxygen
Remaining 2 trace gases (argon, carbon dioxide,
water vapor, methane, ozone, chlorofluorocarbons,
aerosols)
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Permanent vs. Variable Gases
Methane CH4
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(No Transcript)
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Evolution of the Atmosphere

• Solar System Formed (6 billion years ago)
• Planets form from left over dust/gas
• Earth Formed (4.5 billion years ago)
• Initially hot atmosphere consisting mainly of
  hydrogen, helium
• Lightest gases (H, He) escaped gravity into space
• Secondary Atmosphere from Volcanic Emissions
• Water vapor (85), Carbon dioxide (CO2 10) and
  Nitrogen (lt5)
• Nitrogen is chemically stable no reactions with
  gases or Earth
• Oceans Form
• Water vapor condensed and formed clouds as Earth
  cooled
• Precipitation formed oceans (and rivers, lakes
  and glaciers)
• CO2 dissolved in the ocean Nitrogen built up in
  atmosphere.
• Oxygen
• Produced by green-blue algae that evolved in the
  ocean
• Photosynthesis absorbs CO2, releases oxygen

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Evolution of the Atmosphere
3 BY old fossil
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Important Trace Gases

• Carbon Dioxide (CO2)
• Water Vapor (H2O)
• Ozone (O3)
• Methane (CH4)
• Aerosols (solid particles, not a gas)

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Trace Gases Carbon Dioxide (CO2)

• Carbon Dioxide
• A trace gas accounting for only 0.036 of total
  atmospheric mass
• Important to Earths greenhouse effect
• Greenhouse effect gases absorb radiation emitted
  by Earth warming
• Naturally occurring.
• Added through respiration (breathing), volcanic
  activity, organic decay, diffusion from ocean and
  natural and human-related combustion
• Removed through photosynthesis, diffusion into
  ocean, weathering of rocks.

• Human contribution
• Atmospheric CO2 has increased over the past 200
  years due to burning fossil fuels.
• Spring maximum/Fall minimum reflects breathing
  of land plants.

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500,000 Year Record of CO2
Current CO2 360 parts per million
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Carbon Reservoirs (GTC)
Reservoir An area of carbon storage. 1 GTC 1
gigaton 1015 g
750
Input (sources) Removal (sinks)
Decomposition
650
36000
4000?
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Carbon Fluxes (GTC/yr) Pre-Industrial
Flux The exchange of carbon between reservoirs
750
Input Removal
120
lt1
120
lt1
0
Decomposition
90
90
650
36000
4000?
Atmospheric Residence Time 750 GTC / (90120 GTC
yr-1) 3 yr
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Atmospheric Residence Time

• Atmospheric Residence Time The average time a
  molecule of a particular gas resides in the
  atmosphere.
• Residence Time Amount in Reservoir / Rate of
  Input
• Carbon Dioxide (CO2)
• 750 Gigatons / 210 Gigatons per year 3.6
  yr Variable
• Oxygen (O2)
• 750000 Gigatons / 400 Gigatons per year 2000
  yr Well mixed