-
1
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
Chapter 8Contrails and contrail cirrus8.1 Introduction -
Terminology8.2 Contrail formation conditions8.3 Heterogeneous
nucleation on volatile aerosol and soot8.4 Indirect effect of soot
on cirrus8.5 Contrail cirrus8.6 Variability of contrail
properties8.7 Heterogeneous chemistry on contrails8.8 Aerodynamic
contrails
Gayet, 2008, A380
-
2
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
Detection of the contrail of an A380
-
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
Introduction
Contrails develop at lower relative humidity than natural cirrus
and therefore can modify high cloudiness.
Contrails change the radiation budget and the upper tropospheric
moisture budget significantly.
Georgia 13 October 2004 NASA
-
5
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
Introduction 2
Aircraft influence high clouds directly by producing line-shaped
contrails.
Contrails can persist and spread in ice-supersaturated air. The
resulting clusters of contrail-cirrus can be observed on regional
scales, sometimes also in regions without significant air traffic,
because they are advected with the wind field over large
distances.
-
6
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
Introduction 3
Contrails predominantly form when aircraft fly through
preexisting cirrus clouds, sometimes accompanied by the formation
of distrails. The main effect seems to be the formation of a
localized 'cloud hole':
-
7
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
Contrail-cirrus can exert an indirect effect on their own.
Cirrus may have different properties because they nucleate in
regions with preexisting ice and share the available water.
Aircraft influence high clouds indirectly by injecting aerosol
particles that may act as heterogeneous ice nuclei at some point
after emission. In the absence of aircraft emissions, a cirrus
cloud would not have formed or the resulting cirrus would have
different properties.
It is important to recognize that a strong coupling may exist
between the pure direct and indirect effects.
Introduction 4
-
8
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
Chapter 8Contrails and contrail cirrus8.1 Introduction -
Terminology8.2 Contrail formation conditions8.3 Heterogeneous
nucleation on volatile aerosol and soot8.4 Indirect effect of soot
on cirrus8.5 Contrail cirrus8.6 Variability of contrail
properties8.7 Heterogeneous chemistry on contrails8.8 Aerodynamic
contrails
Gayet, 2008, A380
-
9
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
7.7.1 Formation conditions of contrails
Contrails consist of ice particles that nucleate primarily on
aerosols emitted or formed in the plume.
At initial stage contrails grow by deposition of exhaust water
vapor.
Later during their life cycle contrails grow by deposition of
entrained ambient water vapor.
Formation of contrails due to increase in RHI during isobaric
mixing of the hot and humid exhaust gases with colder and less
humid ambient air.
Contrail formation within ~ a wingspan distance behind the
aircraft when S with respect to water is reached.
Threshold temperatures and humidities for contrail formation at
a given flight level are directly specified by thermodynamic
relations.
-
11
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
8.2 Contrail formation conditions
-
12
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
Chapter 8Contrails and contrail cirrus8.1 Introduction -
Terminology8.2 Contrail formation conditions8.3 Heterogeneous
nucleation on volatile aerosol and soot8.4 Indirect effect of soot
on cirrus8.5 Contrail cirrus8.6 Variability of contrail
properties8.7 Heterogeneous chemistry on contrails8.8 Aerodynamic
contrails
-
13
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
8.3 Homogeneous nucleation of contrails in volatile aerosol
Krcher, 1999
Volatile and soot exhaust aerosol are processed by rapid uptake
of H2O and H2SO4 in contrails. Ice crystals that scavenged sulfate
aerosols release larger sulfate droplets upon evaporation.
-
14
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
8.3 Heterogeneous nucleation of contrails on soot
Krcher, 1998
-
15
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
8.3 Heterogeneous nucleation of contrails on soot and volatile
aerosol
after Krcher and Yu, 2009
-
16
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
8.3 Heterogeneous nucleation of contrails on soot and volatile
aerosol
Krcher and Yu, 2009
-
17
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
Chapter 8Contrails and contrail cirrus8.1 Introduction -
Terminology8.2 Contrail formation conditions8.3 Heterogeneous
nucleation on volatile aerosol and soot8.4 Indirect effect of soot
on cirrus8.5 Contrail cirrus8.6 Variability of contrail
properties8.7 Heterogeneous chemistry on contrails8.8 Aerodynamic
contrails
-
18
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
8.4 Indirect effect of soot on cirrus
Krcher et al., ACP, 2007
-
19
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
8.4 Indirect effect of soot on cirrus
Hendricks et al., GRL, 2005
-
22
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
Chapter 8Contrails and contrail cirrus8.1 Introduction -
Terminology8.2 Contrail formation conditions8.3 Heterogeneous
nucleation on volatile aerosol and soot8.4 Indirect effect of soot
on cirrus8.5 Contrail cirrus8.6 Variability of contrail
properties8.7 Heterogeneous chemistry on contrails8.8 Aerodynamic
contrails
-
23
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
8.5 Growth of ice crystals in contrails
Schrder et al., 1999
-
24
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
8.5 Growth of ice crystals in contrails - transition into
contrail cirrus
Schrder et al., 1999
-
25
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
8.5 Growth of ice crystals in contrails - transition into
contrail cirrus
Schrder et al., 1999
-
26
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
8.5 Transition of contrails into contrail cirrus
-
28
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
-
31
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
line-shaped
process
based
all process
based
line-shaped
scaled
line-shaped
process
based
b ~ Dyn(T, RH, 4h)
b ~ Dyn(T, RH, )
logarithmic scale
b ~ C x T x RH
b ~ Dyn(T, RH, 4h)
linear scaleBurkhardt and Krcher, JGR, 2009
8.5 Simulation of contrail cirrus coverage
-
32
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
visible all visible allline-shaped contrails contrail cirrus
new scheme 0.05 0.10 0.50 1.14
Increase in coverage due to ageing contrails regionally very
variable
Increase depends on visibility threshold and overlap
assumptions
8.5 Simulation of contrail cirrus coverage
-
33
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
Chapter 8Contrails and contrail cirrus8.1 Introduction -
Terminology8.2 Contrail formation conditions8.3 Heterogeneous
nucleation on volatile aerosol and soot8.4 Indirect effect of soot
on cirrus8.5 Contrail cirrus8.6 Variability of contrail
properties8.7 Heterogeneous chemistry on contrails8.8 Aerodynamic
contrails
-
34
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
8.6 Variability of contrail cirrus properties-
Interannual variability of contrail coverage
observations
model realizations
model average
Burkhardt and Krcher, JGR, 2009
-
35
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
8.6 Variability of contrail cirrus optical depth
Krcher et al., ACPD, 2009
-
36
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
8.6 Variability of contrail cirrus properties
Krcher et al., ACPD, 2009
Aircraft contrails develop into contrail cirrus by depositional
growth and sedimentation of ice particles and horizontal spreading
due to wind shear. Factors controlling this development include
temperature, ice supersaturation, thickness of ice-supersaturated
layers, and vertical gradients in the horizontal wind field.
-
38
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
Krcher et al., ACPD, 2009
8.6 Variability of contrail cirrus properties
-
39
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
8.6 Variability of contrail cirrus optical depth
Krcher et al., ACPD, 2009
-
40
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
Chapter 8Contrails and contrail cirrus8.1 Introduction -
Terminology8.2 Contrail formation conditions8.3 Heterogeneous
nucleation on volatile aerosol and soot8.4 Indirect effect of soot
on cirrus8.5 Contrail cirrus8.6 Variability of contrail
properties8.7 Heterogeneous chemistry on contrails8.8 Aerodynamic
contrails
-
41
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
8.7 Heterogeneous chemistry on contrailsOzone changes due to
aircraft emissions
Meilinger et al., ACP, 2005
-
42
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
8.7 Heterogeneous chemistry on contrailsPotential of aircraft
aerosols and contrails to produce or destroy ozone
Meilinger et al., ACP, 2005
-
45
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
Chapter 8Contrails and contrail cirrus8.1 Introduction -
Terminology8.2 Contrail formation conditions8.3 Heterogeneous
nucleation on volatile aerosol and soot8.4 Indirect effect of soot
on cirrus8.5 Contrail cirrus8.6 Variability of contrail
properties8.7 Heterogeneous chemistry on contrails8.8 Aerodynamic
contrails
-
46
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
8.8 Aerodynamic contrails
Gierens et al., JAS, 2009, Krcher et al., JAS, 2009
-
47
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
8.8 Aerodynamic contrails
Gierens et al., JAS, 2009, Krcher et al., JAS, 2009
-
49
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
8.8 Aerodynamic contrails
Gierens et al., JAS, 2009, Krcher et al., JAS, 2009
-
50
Chapter 8 - Contrails J. Schneider & Chr. Voigt - Physics
and Chemistry of Aerosols and Ice Clouds
Foliennummer 1Detection of the contrail of an A380Foliennummer
4Foliennummer 5Foliennummer 6Foliennummer 7Foliennummer
8Foliennummer 9Foliennummer 11Foliennummer 12Foliennummer
13Foliennummer 14Foliennummer 15Foliennummer 16Foliennummer
17Foliennummer 18Foliennummer 19Foliennummer 22Foliennummer
23Foliennummer 24Foliennummer 25Foliennummer 26Foliennummer
28Foliennummer 31Foliennummer 32Foliennummer 33Foliennummer
34Foliennummer 35Foliennummer 36Foliennummer 38Foliennummer
39Foliennummer 40Foliennummer 41Foliennummer 42Foliennummer
45Foliennummer 46Foliennummer 47Foliennummer 49Foliennummer 50
