Atmospheric Waves in Titan’s
Atmosphere
Katia Matcheva, Darsa Donelan
University of Florida
Huygens in situ observations
of Titan’s atmospheric
Density profile (1400-0 km)
Temperature profile
derived from density (1400-160 km), z=20-1 km, T=1K
direct measurement (145-0 km), z<0.3 km T=0.25-1K
Pressure profile
derived from density (1400- 160 km)
direct measurements (145-0 km)
Zonal wind profile (150-0 km), V<1 m/s
100
120 140
T [K]
160
210
80
200
135
80
20
35
T profile 0-1400 km
100
200
300
400
300
400
Vertical Scale [km]
100
100
200
300
200
300
400
400
Vertical Scale [km]
•Strobel
2006, T profile, Lz=100-150 km (z=150-300km, T=1-5 K), (z=300-1400km T=10-20K);
saturate ~500 km.
•Wodarg et al. 2006, INMS N2 CH4, z=1025-1600 km; Lz=170-360 km T=4-7K, damped.
•Koskinen
et al. 2011, UVIS stellar occ., z=400-1400 km; Lz=100-200 km, T=10-20 K.
T profile 0-250 km
80
120 140
T [K]
•Lorenz
•This
•
160
10
30
20
40
50
10
20
30
40
50
50
10
20
30
40
50
35
20
18
6
10
30
40
Vertical Scale [km]
Vertical Scale [km]
et al. in press, T profile, Lz=3-7 km, z=100-120 km, T= 1 K, breaking.
work, T profile,
Lz=18 km, up to z=180 km, T= 1.5 K
Lz=35 km, up to z=230 km, T= 2.2 K
V profile 0-140 km
10
6
0 20
60
V [m/s]
•This
•
•
100
10
20
30
18
20
40
50
10
20
30
40
50
50
10
20
30
40
50
35
30
40
Vertical Scale [km]
work, V profile, Lz=6 km, at z=110-135 km, V= 2 m/s
Lz=18 km, at z=180 km, V= 3 m/s
Lz=35 km, at z=40-100 km, V>10 m/s
Vertical Scale [km]
Wave structures
Lz=6 km
Lz=18 km
120
120
100
100
80
80
60
60
40
40
Lz=35 km
120
100
80
60
40
T’;V’
T’;V’
20
20
-2
T’;V’
-1
0
1
2
20
-4
-2
0
2
4
-10
-5
0
5
10
Conclusions
“Quite” regions (no small scale variability <100 km) at
z=200-400 km and 1050-1200 km.
Scales that are detected in INMS and UVIS are
detectable in the HASI T profile as well.
In addition smaller scales (Lz<100 km)are present
throughout the atmosphere at z=400-1100 km.
In the 40-140 km region we detect 6, 18, and 35 km
scales both in the T and V profiles.
The phase difference between T’ and V’ varies and it is
often in the range of 45-90 deg.