vi
CONTENTS
5
.
Relevant Energy Fluxes
.......................................
6
.
TypesofBIocking
...........................................
7
.
Conclusions
................................................
AppendixA
................................................
Appendix
B
................................................
AppendixC
................................................
References
.................................................
Observational Characteristics
of
Atmospheric Planetary Waves
with Bimodal Amplitude Distributions
ANTHONY R
.
HANSEN
1
.
Introduction
................................................
2
.
Frequency Distribution of the Planetary-Wave Amplitude Indicator
...
3
.
Wave Structure of the Two Modes
..............................
4
.
Energetics and Enstrophy Budgets for the
Two
Modes
..............
5
.
Role of Cyclone Waves in Blocking
.............................
6
.
Conclusion
.................................................
References
.................................................
A
Case Study
of
Eddy Forcing
during an Atlantic Blocking Episode
G
.
J
.
SHUTTS
1
.
Introduction
................................................
2
.
The Eddy Straining Mechanism
................................
3
.
Data Manipulation and the Synoptic Situation
....................
4
.
E
Vectors and the Sense
of
Momentum Forcing
...................
5
.
Eddy Vorticity Flux Divergence Patterns
.........................
6
.
Ertel Potential Vorticity Analysis
...............................
7
.
Summary and
Discussion
.....................................
References
.................................................
Part
111
.
Theory
The Effect
of
Local Baroclinic Instability on
Zonal lnhomogeneities
of
Vorticity and Temperature
R
.
T
.
PIERREHUMBERT
1
.
Introduction
................................................
2
.
Eddy Fluxes in the Two-Layer Model
...........................
3
.
Fluxes and Tendencies Associated with
Local
Baroclinic Instability
...
85
89
94
96
97
98
99
101
103
105
113
127
131
132
135
136
139
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147
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165
167
169