Adventures with the First Law from the Earth’s Surface to the Edge of Space Dr. Marty Mlynczak,...
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Transcript of Adventures with the First Law from the Earth’s Surface to the Edge of Space Dr. Marty Mlynczak,...
Adventures with the First Law from the Earth’s Surface to the Edge of Space
Dr. Marty Mlynczak, (B. S. Physics, 1981)
NASA Langley Research Center
May 5, 2006
Univ. of Missouri – St. Louis
Introduction of Co-Author
Collaborators
Astronomy 001 Prof. Richard SchwartzPhysics 10 Prof. Frank MossPhysics 111 Prof. John RidgenPhysics 112 Prof. John RigdenPhysics 200 Prof. Said AgamyPhysics 201 Prof. Wayne GarverPhysics 221 Prof. Jacob LeventhalPhysics 223 Prof. Bernard FeldmanPhysics 225 Prof. Bernard FeldmanPhysics 231 Prof. Peter HandelPhysics 232 Prof. Robert HightPhysics 241 Prof. Dan KelleyPhysics 310 Prof. Bernard FeldmanPhysics 311 Prof. Bernard FeldmanPhysics 331 Prof. Dan KelleyPhysics 356 Prof. Dan KelleyPhysics 381 Prof. Jacob LeventhalHallway discussions Prof. Jerry North
OUTLINE
• Overview of some aspects of Atmospheric Science
• The first law with respect to radiation and chemistry
• Energy conversion in the atmosphere
• Observing the first law from space
• Real-life examples!– Thermostats in the Thermosphere– Hot reactions in the Mesosphere– Cool radiation in the Troposphere – the future challenge
• Summary
Standard Atmosphere Profile
What is a major goal of Atmospheric Science??
To know what the atmosphere will be like at a future date
and
To understand the atmosphere of the past
What will the atmosphere be doing…??
Nowcasting
Climate Change
Weather Forecasting
Atmospheric Chemistry
In a few hours…. In a few days….
In a few years….In a few decades….
Atmospheric Science – A Fusion of Physics!
Relevant processes cover 15 orders of magnitude
Thermodynamics
Quantum Mechanics
Fluid DynamicsChemistry
Computer Science
Solar Physics
Observations
Computation of Atmospheric State
computer model
Atmospheric ModelsGeneral Equations
• Momentum Equation (F = ma)• Conservation of Mass (Continuity)• Conservation of Energy
– a.k.a. the first law of thermodynamics
• Relates change of temperature to energy flux in a volume of atmosphere
t
TC
t
Qp
Focus on how to determine Q/t in the atmosphere
What is Q/t?
• The rate at which a volume of atmosphere gains or loses energy as a result of:
– Radiative processes (absorption, emission)• Infrared emitters: CO2, O3, H2O, NO, O
– Latent energy gain or loss• Water vapor; exothermic reactions
– Heat conduction • Atmosphere/surface • Molecular heat conduction in thermosphere
Thermospheric Energy Balance
Solar EUV, UV
Solar Particlese.g., CMEs
ThermosphereT, , q
100 – 200 km
Infrared CoolingNO, CO2, O
AirglowO(1D), O2(1), etc.
ConductionTides, Waves
Thermospheric Energy Balance
ThermosphereT, , q
100 – 200 km
Infrared CoolingNO, CO2, O
Observing the Infrared Energy of the Thermosphere
TANGENT POINT HoZ
}Ho
N(Ho)
ddx
x
qTpJHN
xo
),,,()(
SABER Measures Limb Radiance (W m-2 sr-1)
- 400 km to Earth Surface -
SABERMeasurements
NO (5.3 m)CO2 (15 m)
Thermostats in the Thermosphere
A look at radiation from Nitric Oxide (NO) during an intense geomagnetic storm
How does a thermostat work?
Concept of Infrared ‘Natural Thermostat’
Solar Storm
Energy Enters
Atmosphere
Atmosphere StronglyRadiates
April 18
April 15
SABER NO (5.3 m) Limb Radiance Before and During Storm
80 S, 350 W
Thermospheric Infrared Response
• NO 5.3 m enhancement by far the most dramatic in terms of overall magnitude and radiative effect
• Increases by over an order of magnitude in ~ 1 day
• Changes in NO emission are due to changes in:– NO abundance
– Kinetic temperature
– Exothermic production of NO vibrational levels
– Atomic Oxygen
• Examine the Thermospheric NO response [Mlynczak et al., GRL, 2003]– Energy loss profiles (W/m3) (vertical profiles)
– Energy fluxes (W/m2) from thermosphere
Vertical Profile of Energy Loss by NOLatitude 77 S
Before Storm During Storm
This is Q/t !
Another Perspective of the Energy Loss Rate
First Law of Thermodynamics:
Can express total energy loss (W m-3) in units of K/day
Use MSIS as background atmosphere (for now) for Cp
Emphasize:
• Energy loss rate in K/day does not necessarily equal the radiative cooling rate
True Cooling Rate < Energy Loss Rate
t
TC
t
Qp
NO Energy Loss Rates Expressed in K/day
Prior to Storm During Storm
Example: Cooling Rates at 52 N – April 2002
Quiescent
Storm
Vertical Profile of Energy Loss by NOLatitude 77 S
Before Storm During Storm
Vertically integrate these to get energy fluxes
Animation Vertically Integrated Thermospheric Energy Loss (W/m2)
Southern Hemisphere Polar Projection
NO Radiated Energy W m-2
2.5 mW/m2
1.5 mW/m2
0.5 mW/m2
After Mlynczak et al. 2003
Thermospheric NO Radiated Energy W m-2 Day 105
Thermospheric NO Radiated Energy W m-2 Day 106
Thermospheric NO Radiated Energy W m-2 Day 107
Thermospheric NO Radiated Energy W m-2 Day 108
Thermospheric NO Radiated Energy W m-2 Day 109
Thermospheric NO Radiated Energy W m-2 Day 110
Thermospheric NO Radiated Energy W m-2 Day 111
Thermospheric NO Radiated Energy W m-2 Day 112
Thermospheric NO Radiated Energy W m-2 Day 113
Thermospheric NO Radiated Energy W m-2 Day 114
Thermospheric NO Radiated Energy W m-2 Day 115
Thermospheric NO Radiated Energy W m-2 Day 116
Thermospheric NO Radiated Energy W m-2 Day 117
Thermospheric NO Radiated Energy W m-2 Day 118
Thermospheric NO Radiated Energy W m-2 Day 119
Thermospheric NO Radiated Energy W m-2 Day 120
NO “Thermostat” Summary
• Dramatic increase in NO 5.3-m emission observed in April 2002 storms (and in October 2003 storms as well)
• Emission increases by up to factor of 10 in ~ 1 day
• Effects observed from pole to equator
• Enhancement lasts ~ 3 days and dies out
• Radiative loss comparable to energy inputs – estimates being refined
• Physics of NO enhancement still being sorted out –– Temperature increase?– Atomic Oxygen increase?– NO increase?– Exothermic reaction emission?
Mesospheric Energy Balance
Solar EUV, UV
Infrared CoolingNO, CO2, O
AirglowO(1D), O2(1), etc.
Heat
Quantuminternal
Chemicalpotential
Hot Reactions in the Mesosphere
Latent Energy in the Thermosphere and Mesosphere
UV energy absorbed primarily by O2 or O3
Energy goes into three separate pools initially: - Chemical potential energy
• Energy used to dissociate moleculeO2 + hv O + O
- Internal energyO3 + hv O2(1) + O(1D)
- Heat
Internal energy radiated to space or quenched to heat
Chemical potential energy realized by exothermic reactions
Key Exothermic Reactions in the Mesosphere
“The Magnificent Seven”
H + O3 OH + O2
H + O2 + M HO2 + M
HO2 + O OH + O2
OH + O H + O2
O + O2 + M O3 + M
O + O + M O2 + M
O + O3 + O2 + O2
Total Solar Heating and Heating Due to Reaction of H and O3 – Photochemical Theory
After Mlynczak and Solomon, JGR, 1993
How do we measure the rate of heating due to a chemical reaction??
Chemical Heating Rates from the OH Airglow
A key reaction is that of atomic hydrogen (H) and ozone (O3)
H + O3 OH + O2 Hf = 76.9 kcal/mole
This reaction (fortunately) preferentially populates the highest-lying vibrational quantum states, = 9, 8, 7, 6
Due to the low density in the mesosphere, these statesradiate copious amounts of energy
Rate of emission from OH proportional rate of reaction
Measure emission rate, readily derive rate of heating
Time-Lapse Movie
Zonal Mean, NightMay 23 2002 through July 16 2002
Energy Deposition RateH + O3 OH() + O2
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
H + O3 OH + O2 Energy Deposition
Cool Radiation in the Troposphere
Development and Flight of FIRST
Far-Infrared Spectroscopy of the Troposphere
Far-Infrared Spectroscopy of the Troposphere
Far-IR Mid-IR
Top of Atmosphere – Nadir View
Far-Infrared Spectroscopy of the Troposphere
Annual mean TOA fluxes for all sky conditions from the NCAR CAM
Reference: Collins and Mlynczak, Fall AGU, 2001
Far-Infrared Spectroscopy of the Troposphere
Mid-IRFar-IR
Clear-Sky Spectral Cooling Rate
Reference: Mlynczak et al; 1998
Far-Infrared Spectroscopy of the Troposphere
Observed
Unobserved
Spectrally Integrated Cooling – Mid-IR vs. Far-IR
Reference: Mlynczak et al; 1998
FIRST – Overview
• Program developed under NASA Instrument Incubator Program (IIP)
• Develop technology necessary for routine measurement from space of the far-infrared spectrum 15 to 100 m
• Many compelling science issues (greenhouse effect; cirrus etc.)
• FIRST is a Michelson FTS @ 0.625 cm-1 spectral resolution
• IIP requires technology to be demonstrated in a relevant environment
• FIRST successfully demonstrated June 7 2005 on high altitude balloon from Ft. Sumner, NM
FIRST Balloon Payload System
Interferometer Cube
Aft Optics
LN2 Volume
Beamsplitter
Polypropylene Vacuum Window
Remote Alignment Assembly
Scatter Filter
Scene Select Mirror
Scene Select Motor
Interdewar Window
Active LN2 Heat Exchanger
Passive LN2 Heat Exchanger
FIRST on the Flight Line June 7 2005
FIRST “First Light” Spectrum
H2O
O3CO2
window
Preliminary Calibration
FIRST Spectra Compared with L-b-L SimulationDemonstration of FIRST Recovery of Spectral Structure
Note: FIRST, LbL spectra offset by 0.05 radiance units
FIRST Lands Safely after a Successful Flight
Closing Thoughts
• Atmospheric energetics and radiation remain a frontier of research
• Unique space-based assets now observing the heat balance of the mesosphere and lower thermosphere
• New technology being developed to allow a more comprehensive determination of the tropospheric energy balance and climate
PHYSICS RULES!
Extras
FIRST – Status and Summary
• FIRST successfully completed technology demonstration flight 6/2005– Met or exceeded technology goals
• Preliminary calibration applied here from flight blackbody
• Measured entire thermal emission spectrum on one focal plane with one instrument
• Agreement in window with CERES, AIRS is excellent
• Fidelity of measured far-IR spectra with L-b-L codes is outstanding
• Continuing to improve calibration:– Absolute cal. using laboratory and flight blackbodies
– Improved phase corrections
• Anticipate deployment in future campaigns and science opportunities
FIRST, AIRS, and CERES Window Radiance Comparisons
• Four AIRS footprints very close to FIRST• Several CERES Window channel footprints close to FIRST• FIRST Radiance at 900 cm-1 is 0.15 W m-2 sr cm-1
– Corresponds to a skin temperature of 317.7 K– Air temperature at Ft. Sumner ~ 90 F or 305 K
• AIRS skin temperature closest to FIRST is 318.5 K
• CERES Window Channel (844 to 1227 cm-1) – Measured radiance is 41.75 W m2 sr-1 closest to FIRST– Computed radiance using ABQ sonde, 318 K skin Temp is 41.83 W m2 sr-1
– Computed radiance for 297 K skin temp is 30.76 W
Conclude that within 1 K both CERES and AIRS support FIRST skin temperature, and hence, absolute
calibration of the FIRST instrument
SOLAR
HEAT
QUANTUMINTERNAL CHEMICAL
POTENTIAL
N(4S), N(2D), ionse-, O, etc.
O2(1), OH() O2(1), CO2(2) NO(, O33
O1D
UV, Visible& Infrared
Loss
Airglow LossTrue Cooling
Energy Flow in the Upper Atmosphere
SEE
TIDI
SABERGUVI
TIDI
SABER Instrument
75 kg, 77 watts, 77 x 104 x 63 cm, 4 kbs
SABER Experiment Viewing Geometry and Inversion Approach
TANGENT POINT HoZ
}Ho
N(Ho)
ddx
x
qTpJHN
xo
),,,()(
VMR (q) known, infer J, infer T J known, infer q (O3, H2O, etc.)
Determine Volume Emission Rate, Derive T/t
The SABER Experiment on TIMED
Channel Wavelength Data Products Altitude Range
CO2 15.2 m Temperature, pressure, cooling rates 15-100 km
CO2 15.2 m Temperature, pressure, cooling rates 15-100 km
CO2 14.8 m Temperature, pressure, cooling rates 15-100 km
O3 9.6 m Day and Night Ozone, cooling rates 15 - 95 km
H2O 6.3 m Water vapor, cooling rates 15-80 km
CO2 4.3 m Carbon dioxide, dynamical tracer 90-160 km
NO 5.3 m Thermospheric cooling 100 - 300 km
O2(1) 1.27 m Day O3, solar heating; Night O 50-100 km
OH() 2.0 m Chemical Heating, photochemistry 80-100 km
OH() 1.6 m Chemical Heating, photochemistry 80-100 km
Observing the First Law from Space
Far-Infrared Spectroscopy of the Troposphere
• Up to 50% of OLR (surface + atmosphere) is beyond 15.4 m
• Between 50% and 75% of the atmosphere OLR is beyond 15.4 m
• Basic greenhouse effect (~50%) occurs in the far-IR
• Clear sky cooling of the free troposphere occurs in the far-IR
• Radiative feedback with H2O and greenhouse gas increase is in the far-IR
• Cirrus radiative forcing has a major component in the far-IR
• Longwave cloud forcing in tropical deep convection occurs in the far-IR
• Improved water vapor sensing is possible by combining the far-IR and standard mid-IR emission measurements
Direct Observation of Key Atmospheric Thermodynamics
Compelling Science and Applications in the Far-Infrared
FIRST – Sensitivity to Cirrus CloudsQuickTime™ and aGraphics decompressorare needed to see this picture.
-50
-30
-10
10
10 30 50 70 90 110 130 150
BT
D (
250-
559.
5cm
-1 )
(K
)
Effective Size (µm)
Brightness temperature difference between two channels 1=250.0 cm-1 and 2=559.5 cm-1
as a function of effective particle size for four cirrus optical thicknesses
FIRST spectra can be used to derive optical thickness of thin cirrus clouds ( < 2). Reference: Yang et al., JGR, 2003.
Reference: Yang et al; 2003
74.1° inclination625 km circular
4 remote sensing instruments
Mission Lifetime: 2 years (Jan. 2002 - Jan. 2004)Extended Mission: 2 years (Jan. 2004- Jan. 2006)
Concept of Infrared ‘Natural Thermostat’
Solar Storm
Energy Enters
Atmosphere
Atmosphere StronglyRadiates
SOLAR
HEAT
QUANTUMINTERNAL CHEMICAL
POTENTIAL
N(4S), N(2D), ionse-, O, etc.
O2(1), OH() O2(1), CO2(2) NO(, O33
O1D
UV, Visible& Infrared
Loss
Airglow LossTrue Cooling
Solar Energy Deposition in the Atmosphere
Radiative Energy within the Atmosphere
Radiant energy from the Sun is absorbed and mayheat the atmosphere
Also is the source of latent energy in the atmosphere
Infrared energy emitted by atmospheric speciestakes energy from thermal field and it is eventuallylost to space – true cooling of the atmosphere
Infrared emitters: CO2, O3, H2O, NO, O
Release of Latent Energy within the Atmosphere
Besides electromagnetic radiation, release of latentenergy within the atmosphere causes it to heat
1. Condensation of water vapor – troposphere
2. Exothermic reactions in the upper atmosphere
In many regions, latent energy release is the dominantmechanism for heating the atmosphere
Major Atmospheric Heating and Cooling Mechanisms
• Thermosphere– UV absorbed by O2
– Exothermic reactions
• Mesosphere– UV absorbed by O3, O2
– Exothermic reactions
• Stratosphere– UV, visible absorbed by O3, NO2
– Exothermic reactions
• Troposphere– UV, VIS. absorbed by O3, NO2, O2
– Condensation of H2O– Conduction with surface
• Thermosphere– NO at 5.3 m– O at 63 m– Heat conduction
• Mesosphere– CO2 at 15 m
• Stratosphere– CO2 at 15 m– O3 at 9.6 m– H2O> 15 m
• Troposphere– H2O > 15 m– CO2 at 15 m– O3 at 9.6 m
Heating Cooling
Major Atmospheric Heating and Cooling Mechanisms
• Mesosphere
– Exothermic reactions
• Thermosphere– NO at 5.3 m
• Troposphere– H2O > 15 m
Heating Cooling
How do we observe these from space?
FIRST Flight Specifics
• Launched on 11 M cu ft balloon June 7 2005• Float altitude of 27 km• Recorded 5.5 hours of data• 1.2 km footprint of entire FPA; 0.2 km footprint per detector• 15,000 interferograms (total) recorded on 10 detectors • Overflight of AQUA at 2:25 pm local time – AIRS, CERES, MODIS• Essentially coincident footprints FIRST, AQUA instruments• FIRST met or exceeded technology development goals
– Optical throughput demonstrated by spectra from center and edge of focal plane detectors
– Exceeded spectral bandpass – 20 to 1600 cm-1 demonstrated vs. 100 to 1000 cm-1 required
• FIRST, AIRS, CERES comparisons in window imply excellent calibration (better than 1 K agreement in skin temperature)
FIRST records complete thermal emission spectrum of the Earth at high spatial and spectral resolution
FIRST Spectra Comparisons with L-B-L using AIRS Retrievals
L-b-L does not yet include FIRST Instrument Response Functions