Atmosphere, Insolation, and

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Atmosphere, Insolation, andGlobal Warming
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Atmospheric Composition, Temperature, and
Function  

• Atmospheric Composition  
• Atmospheric Profile
• Atmospheric Temperature  
• Atmospheric Function  

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Composition

• Permanent Gases
• 78 by volume  -  Nitrogen
• 21 by volume  -  Oxygen
• 0.9 -  argon, etc.
• Variable Gases
• Carbon dioxide  --  0.035  (350 ppm)
• Water Vapor
• variable from place to place
• can be lt1 or up to 3 or 4
• ability to hold moisture is a function of
  temperature
•  Ozone  --  layer at about 15 miles absorbs UV
  radiation

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Composition

• Variable Gases (cont.)
• Gases from natural and anthropogenic pollution
• Particulates - scatter incoming solar radiation
  and hence result in cooling
• Volcanic Dust (or comet dust) cools temperatures
  (e.g. Mt Pinatubo).  The key is that the dust has
  to be thrown up into the stratosphere and contain
  sulfur
• Dust particles vary in time and space
• Dust particles (over south Asia strong effect)
• Sea Salts
• Fire/smoke ash Oil Fires in Kuwait cooled ground
  temperatures

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Atmospheric Profile  

• Atmosphere extends to 32,000 km (20,000 mi) from
  surface
• Exosphere begins at 480 km (300 mi)
• Three criteria to examine atmosphere
• Composition
• Pressure
• Temperature
• Function

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Atmospheric Composition

• Homosphere inner atmosphere
• Surface to 80 km (50 mi)
• Gases evenly blended
• Heterosphere outer atmosphere
• 80 km (50 mi) outwards
• Layers of gases sorted by gravity

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Vertical Structure of theAtmosphere

• Animated Introduction (AtmoLayersAnim)
• Pressure always decreases as go up (chips)
• Temperature more complicated

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• Pressure
• Decreases with increasing altitude

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• Air pressure decreases with increasing altitude
  but not at a constant rate

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Atmospheric Pressure at Various Altitudes
Expressed as a Percentage of Sea-Level Pressure
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Atmospheric Pressure
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Profile of Atmosphere
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• Troposphere (where our weather happens!)
• Environmental Lapse Rate - 3.5 F/1000 ft    6.5
  C/1000 meters
• Average height of 7.5 miles 12 kilometers
  (varies with latitude)
• Zone of weather (see weather only in this lower
  layer)
• Has lots of water vapor
• Vertical movements (turbulence)
•  Tropopause top of troposphere "cap" on weather
• Stratosphere
• Temperature increase with height very stable so
  don't have weather has the ozone layer
• Mesosphere
• Thermosphere
• Exosphere

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AtmosphericTemperature Profile
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Atmospheric Function

• Ionosphere
• Absorbs cosmic rays, gamma rays, X-rays, some UV
  rays
• Ozonosphere
• Part of stratosphere
• Ozone (O3) absorbs UV energy and converts it to
  heat energy
• Chlorine from CFCs destroys O3

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EarthsProtectiveAtmosphere
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Natural Radiation Balance

• Insolation (incoming solar radiation) must
  balance outgoing terrestrial radiation, or we're
  in trouble...
• This is monitored carefully, and complicated
• Note that there are latitudes of surplus and
  latitudes of deficit but on whole, earth balances
  (AnimLongShortWorld.gif)
• This means that somehow latitudes with energy
  surplus must transfer energy to latitudes of
  energy deficit

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Natural Radiation Balance

• Insolation (solar Short Wave)
• Absorbed water vapor, ozone, clouds
• Scattering
• Albedo (reflected)
• Introductory NASA movie (ExplainSWAlbedo.mov)
• We alter the albedo, such as adding soot
• Changes seasonally, and globally
• What makes it to earth's surface is absorbed -
  mostly in the tropics and subtropics

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Natural Radiation Balance

• Outgoing Long Wave
• Long Wave Radiation (ExplainCeresLongWave.mov)
• Sensible Heat Flux (you too can measure it)
• Latent Heat Flux (evaporation, transpiration)
• The difference is as simple as this...

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Natural Radiation Balance

• Why ocean-land difference?

• Absorption within atmosphere
• (water vapor, dust, carbon dioxide)
• Emission by Clouds

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Natural Radiation Balance

• Outgoing Long Wave
• Some key points
• Colder as you go up (lapse rate)
• Clouds and water vapor trap heat
• More longwave in tropics and subtropics
• Movie showing this for the whole year
  (LongwaveRadGSFC2157.mpg)
• More detail (CloudForcingExplain.mov)
• Without clouds, clear sky radiation
  (ClearSkyNetRadiation.mov)

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Natural Radiation Balance

• Heat Transfer Issues (2nd Law Thermodynamics) --
  think of a camp fire
• Radiation Heat moves with electromagnetic
  radiation (light) Heat from the Sun is
  transferred this way So...radiative heat
  transfer is responsible for warming oceans and
  atmosphere, and for re-radiating heat back into
  space
• Conduction air molecules coming into contact
  with the heated (cooled) surface are themselves
  heated (cooled) and have the same effect on
  adjacent molecules So...an air layer only a few
  centimeters thick becomes less (more) dense than
  the air above
• Convection (just like a stove) arising when the
  heated air layer tries to rise and the denser
  layer above tries to sink So...small turbulent
  eddies build and the heated layer expands from a
  few centimeters to a layer hundreds, or thousands
  of feet deep, depending on the intensity of solar
  heating
• Later, we will cover Advection horizontal
  transport ...Warm advection brings warm air into
  a region. Cold advection brings cold air into a
  region. Moisture advection brings moister air...

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Human Influence on the Global Radiation
BudgetGlobal Warming the Greenhouse Effect

• General theory of greenhouse gases
• We burn fossil fuels...especially the USA...where
  we have our love affair with cars
• Everybody agrees carbon dioxide increasing
• Big bad gas is carbon dioxide (CO2), along with
  other greenhouse gases...
• Methane carbon monoxide, e.g., from fires
  nitrous oxide others (e.g., spray cans, your
  tennis ball can)
• Increasing greenhouse gases should warm the
  troposphere
• Discovering forcing agents of temperature
  change is difficult

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Human Influence on the Global Radiation
BudgetGlobal Warming the Greenhouse Effect

• Difficulty
• Carbon cycles naturally in difficult to quantify
  pathways (for example, volcanoes produce lots of
  greenhouse gases)
• We all contribute in different ways
• You can find your own personal emission of carbon
  dioxide by going here http//yosemite.epa.gov/oar
  /globalwarming.nsf/content/ResourceCenterToolsGHGC
  alculator.html
• My spouse and I have an emission of 10,608
  pounds/year
• Not just in the USA, but all industrialized
  places...and growing nations will want benefits
  of burning...and deforestation...
• The net effect shows great increases

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Human Influence on the Global Radiation
BudgetGlobal Warming the Greenhouse Effect

• Long-Term Perspectives reason not to panic
• Ancient worlds
• 600 million years ago, Earth may have been
  brought out of an ice world by release of
  methane
• Cretaceous (65 million years ago) before comet
  hit, several periods with more carbon dioxide and
  biomass than today
• Eocene warmth from mostly methane increase (no
  ice in the Arctic!) but also from higher carbon
  dioxide
• Late Tertiary (last 5 million years), gradual
  cooling of Earth

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Human Influence on the Global Radiation
BudgetGlobal Warming the Greenhouse Effect

• Long-Term Perspectives reason not to panic
• Pleistocene (last 2.5 million years of
  glacial/interglacial yoyo), many drastic shifts
  in carbon dioxide naturally
• Ice cores show drastic changes in greenhouse
  gases (latest core data shows changes go back
  800,000 years!)
• These data show humans evolved in a world of BIG
  carbon dioxide changes
• BIG temperature changes coincide with greenhouse
  gas changes, but cause and effect unclear
• Many voice concern that recent changes are a big
  jump from past changes
• Last 500 years, see cooling during little ice
  age and warming in the late 20th century
  (TempChLast500yrGSFC2319.mpg)
• In the news, 100 years seems like a long time,
  but to an educated person like you, could their
  be a political purpose?

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Human Influence on the Global Radiation
BudgetGlobal Warming the Greenhouse Effect

• Current Global Warming Panic
• Media has a limited intelligence as a group --
  able to buzz around one climate change concept
  and recirculate it and blame single events on
  global warming (mental moron mindset ... that
  good stories have legs)
• Those advocating of Global Warming Panic
• Point to big warming in 20th century
  (TempChanges20thCent.mpg)
• The warming of "sensitive" areas of the globe,
  such as the Arctic ocean (ArcticWarmingLarge.mov)
  and Greenland
• Change the Gulf Stream
• Models (GreenhouseModel.mpg) show big future
  warming...
• Agriculture will be affected
• Extinctions of thousands of species by 2050 as
  warming leaves cold refuges that no longer
  exist

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Human Influence on the Global Radiation
BudgetGlobal Warming the Greenhouse Effect

• Those advocating of Global Warming Panic
• Sea level rise as ice caps melt (note the scale)
• NOT TRUE!! (ice sheets are not melting article)
• March 2006 Summary in Science Magazine...
  (LessIceHighSeas.pdf)
• Al Gores movie (Inconvenient Truth) blaming a
  host of troubles on global warming and those who
  would do nothing about it...
• Even fashion trends come into the picture

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Human Influence on the Global Radiation
BudgetGlobal Warming the Greenhouse Effect

• Those advocating of Global Warming Panic
• Put cartoons in the K-12 curriculum
• Environmental organizations stage events and
  concerts...
• Companies show their responsibility...
• Lots of money involved where scientists advocate
  need for research
• Such as making plankton bloom by adding iron (an
  nutrient lacking in tropical oceans)
• Such as understanding role in changing ocean pH,
• Such as ice ages ending from more CO2 leading in
  the future to a permanent El Nino world

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Human Influence on the Global Radiation
BudgetGlobal Warming the Greenhouse Effect

• Skeptics of perspective advocate
• Not all CO2 is bad! Increases have helped green
  the earth (more plant productivity) over the last
  few decades (npp_change.mov)Nemani, R.R.,
  Keeling, C.D., Hashimoto, H., Jolly, W.M., Piper,
  S.C., Tucker, C.J., Myneni, R.B. and Running,
  S.W., 2003. Climate driven increases in global
  terrestrial net primary production from 1982 to
  1999. Science. (June-06-2003)
• There are lots of signals in changes in climate,
  and OTHER than greenhouse gases that can cause
  warming
• Solar flux explains a lot
• Look at last 1000 years ... and the regional
  warming in the last century is an increase from a
  "Little Ice Age", so we see Austrian glaciers
  like the Pasterze and Oregon glaciers like the
  South Cascade decline...but others like the
  Hubbard glacier (in Alaska) is increasing!

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Human Influence on the Global Radiation
BudgetGlobal Warming the Greenhouse Effect

• More Signals
• Desertification (across the globe) causes warming
• Loss of vegetation means less plant transpiration
  cooling
• Urban heat island causes warming
• The temperature increase curve you see all the
  time is biased!
• Urban growth
• Compare Phoenix with away from the Phoenix
  solar flux trends...
• Look at Chicago...Cities bias the signal...
• Look at Atlanta roads

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Human Influence on the Global Radiation
BudgetGlobal Warming the Greenhouse Effect

• More Signals...
• Satellite record does NOT show GLOBAL warming,
  only regional warming and cooling ...
• Past computer predictions just haven't worked
  very well
• Minimum temperatures are increasing, but so is
  rain (and that's better than drought)
• Some polar ice builds and some polar ice
  recedes...not simple (GreenlandIceChangeGSFC1254.m
  pg)
• New evidence that cold periods in our current
  climate state (Holocene) yield poor Asian
  Monsoons with devastating agricultural
  consequences
• If the world was able enact curbs on fossil fuel
  consumption, would the effect be noticeable?

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Human Influence on the Global Radiation Budget
Decline of  Stratospheric (not city) Ozone
 

• Ozone as a positive feedback equilibrium
• We do NOT know if our Biosphere would be
  devastated by a drastic drop in Ozone
• Unlike greenhouse gases, we do NOT have a record
  of prior dips and Biosphere survival (but the
  potential for research is great, just starting,
  please join!)

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Basics of ozone depletion...

• Ozone made in the tropics in the stratosphere
  where solar radiation is abundant and
  redistributed to the poles
• Chlorine (and bromine) are bad ... and the key
  bad player is the chlorofluorocarbon (CFC)
  molecule that breaks down ozone
• Spring hole over Antarctica is constrained by
  polar vortex that breaks down in the late spring
• Size of hole has grown
• Depth of hole has grown
• 2006 over Antarctica the worst yet 
• Arctic hole problem getting worse (2005, 2nd
  Lowest), but more complicated...
• There is a positive feedback to keep the hole
  growing

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Ozone Review

• Solar radiation initially makes stratospheric
  ozone
• Ozone made in tropics but tropical volcanoes can
  influence ozone, although the effect short
  lived...
• Ani of how stratospheric ozone blocks UV
  radiation (OzoneHoleGSFC1203.mpg)
• CHLORINE IS THE MAIN AGENT OF OZONE DESTRUCTION
• Example of 1999 Antarctic Ozone hole
  (Ozone99GSFC717.mov)
• How chlorine destroys an ozone molecule
  (ClEatOzoneGSFC825.mov)
• Antarctic Holes seen by satellite through 2000
  (OzoneHoleGSFC1203.mpg)

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Variable Atmospheric Components  

• Natural Sources  
• Natural Factors That Affect Air Pollution  
• Anthropogenic Pollution  
• Benefits of the Clean Air Act

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Natural Factors That Affect Air Pollution  

• Winds
• Local and regional landscapes
• Temperature inversion

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Sources of Natural Variable Gases and Materials
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Alaskan Wildfires
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Temperature Inversion
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Anthropogenic Pollution  

• Carbon monoxide
• Photochemical smog
• Industrial smog and sulfur oxides
• Particulates

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Pollution Sources
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Biomass Burning
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Air Pollution
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Photochemical Smog
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Benefits of the Clean Air Act

• Total direct cost 523 billion
• Direct monetized benefits 5.6 to 49.4 trillion
  average 22.2 trillion
• Net financial benefit 21.7 trillion
• 206,000 fewer deaths in 1990!

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Human Influence on the Global Radiation Budget

• Personal Thoughts
• I (You) can work for either side
• Two BIG Choices
• Trust technology to save you e.g., try to
  sequester carbon dioxide or erect a giant solar
  shield
• Take personal responsibility
• All individual action can make a difference (star
  fish story)