NASA Technical Reports Server (NTRS) 20170000891: Using CYGNSS to Observe Convectively Driven Near-Surface Winds in Tropical Precipitation Systems During Madden-Julian Oscillation Events

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by  NASA Technical Reports Server (NTRS)

Using CYGNSS to Observe Convectively Driven Near-Surface Winds in
Tropical Precipitation Systems during Madden-Julian Oscillation Events
Timothy J. Lang1, Xuanli Li2, John Mecikalski2, Kacie Hoover2, Tyler Castillo2, and Themis Chronis2
1NASA Marshall Space Flight Center, Huntsville, Alabama
2University of Alabama in Huntsville
1. Introduction 3. Simulated CYGNSS Views of Convection 4. CYGNSS OSSE of MJO Convection
The Cyclone Global Navigation OKLMA 1411 UTC
Satellite System (CYGNSS) is a
multi-satellite constellation that
launched 15 December 2016.
T. Ashcraft
1
The primary objective of
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1
CYGNSS is to use bistatic 0
0
2
Global Positioning System 2

r
r
(GPS) reflectometry to
e
e
b
accurately measure near- b
m
o
surface wind speeds within the
t
e
c
heavily raining inner core of
v
O
o
tropical cyclones.
N
CYGNSS also features rapid revisit times over a
given region in the tropics - ranging from several
minutes to a few hours, depending on the
constellation geometry at that time. Despite the
focus on tropical cyclones, the ability of CYGNSS 1800 UTC
to provide rapid updates of winds, unbiased by
the presence of precipitation, has many other
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1
potential applications related to general tropical
0
convection.
2

r
e
b
2. Data and Methodology
m
1830 UTC
e
c
e
D
Forecast:
Forecast: Water Vapor
Temperature
Mixing Ratio at 18 UTC
n Anomaly at 18 UTC
2011-11-28
2011-11-28
u
R
892 km

e
r
u
Initiate
t
a
N
Terminate

CYGNSS OSSE
5
-
• Single-nest
S
O
• MJO tropical
E
storm
G
TAKE HOME MESSAGE TAKE HOME MESSAGE
GEOS-5 Nature Run
• 7-km resolution, 30-minute updates
CYGNSS should detect mesoscale wind features such as Westerly Wind This was a tropical storm during an MJO onset that did not develop further.
• Simulates tropical convection but not MJO
Bursts and gust fronts, even in the presence of heavy precipitation. CYGNSS CYGNSS Data Assimilation helped the model to resist the tendency of the
• Apply CYGNSS End-To-End Simulator (E2ES)
likely will provide benefits to future tropical oceanic field campaigns that should Control Run to further strengthen the storm. In addition, storm track position
be considered during their planning processes. was significantly improved over the Control.
Contact Info: Timothy Lang, [email protected]
This research is supported by the NASA Weather program