Inspiration for REMOTE SENSING satellites

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Inspiration for REMOTE SENSING satellites

• Or
• What could have happened to lidar if Nov. 2000
  had turned out differently

R. A. Brown 2005 EGU Lidar Mt. Hood
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Evolution and current Status of Surface Pressure
Fields from Scatterometer data

• And maybe from radiosonde (WindSat) data

R. A. Brown 2005 EGU Lidar Mt. Hood
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State of The analytic solution for a PBL
fV K Uzz - pz /? 0 fU - K Vzz pz
/ ? 0 The solution, U (f, K,?p ) was found by
Ekman in 1904.
Unfortunately, this was almost never observed.
fV K Uzz - pz/? 0 fU - K
Vzz pz/? A(v2w2) Solution, U (f, K,?p )
found in 1970. OLE are part of solution for 80
of observed conditions (near-neutral to
convective).
Unfortunately, this scale was difficult to
observe.
The complete nonlinear solution for OLE exists,
including 8th order instability solution,
variable roughness, stratification and
baroclinicity, 1996. Being integrated into MM5,
NCEP (2005)
R. A. Brown 2005 EGU
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Geostrophic Wind
VG ?P / (? f )
The nonlinear Ekman layer mean wind
Mid- PBL
V ?P / (? f) - Fviscous
Geostrophic Wind direction
25 (Stable strat.)
18 (neutral stratification)
Surface wind
5 (Unstable strat.)
-10 to 40 (Thermal Wind Effect)
R. A. Brown 2003 U. ConcepciÓn
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The Dinosaur Cartoon (next slide)   This Gary
Larson cartoon struck me for some reason,
probably because it is very close to how I feel
these days, simply changing a couple of words.
R. A. Brown 2005 EGU Lidar Mt. Hood
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The dinosaur lecturer says The pictures pretty
bleak, Gentlemen..the worlds climates are
changing, the mammals are taking over, and we
have a brain about the size of a walnut.
R. A. Brown 2005 EGU Lidar Mt. Hood
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The analytic PBL modeller says The pictures
pretty bleak, Gentlemen..the worlds climates
are changing, the numerical modellers are taking
over, and we have a brain about the size of a
coconut.
R. A. Brown 2005 EGU Lidar Mt. Hood
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The dinosaurs successfully morphed into birds,
and I successfully morphed into a satellite
remote sensing specialist.
R. A. Brown 2005 EGU Lidar Mt. Hood
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Surface Pressures from Space
1. The indirect model connects surface winds to
gradient winds and hence to surface pressure
gradients through the PBL model (analytically) 2.
The Direct Pressure Model Function, (PMF)
connects scatterometer backscatter to NCEP
surface pressure gradient directly (empirically)
R. A. Brown 2004
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The nonlinear solution applied to satellite
surface winds yields accurate surface pressure
fields when compared to numerical models. These
results show
Agreement between satellite and ECMWF
pressure fields indicate that both Scatterometer
winds and the nonlinear PBL model (VG/U10) are
accurate within ? 2 m/s.
A 3-month, zonally averaged offset angle ltVG,
U10gt of 19 from scatterometer data suggests the
mean PBL state is near neutral (the angle
predicted by the nonlinear PBL model).
Swath deviation angle observations
successfully infer thermal wind and
stratification.
When pressure gradients are used as surface
truth (rather than GCM or buoy winds) higher
winds are obtained .
VG (pressure gradients) rather than U10 could
be used to initialize GCMs
R. A. Brown 2005 EGU
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R. A. Brown 2004 EGU
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Surface Pressures
QuikScat analysis
ECMWF analysis
J. Patoux R. A. Brown
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Surface Pressures verification applications
Note A special tropical PBL is patched at the
equator
R. A. Brown 2004
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Applications
Better Storms Definition
Dealiasing wind direction with SeaWinds
Better GCM Progs (initialization with ?P)
Higher Winds ( heat fluxes) in Climate models
Evolution of Fronts Cyclones
R. A. Brown 2004 WRAGU
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(JPL)
Raw scatterometer winds
UW Pressure field smoothed
JPL Project Local GCM nudge smoothed (with
ECMWF fields) Dirth
R. A. Brown 2005 EGU
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Producing smooth wind fields
Gap from rain
Direction information is poor
R. A. Brown 2003 U. ConcepciÓn
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The quikScat scatterometer real-time data is
currently being used at NCEP in the
forecasters' display as surface pressure fields.
They are more comfortable with these than wind
fields it is more compatible with other data.
R. A. Brown 2005 EGU Lidar Mt. Hood
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Dashed ECMWF
R. A. Brown 2005 EGU
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The application of scatterometer data to storms
and frontal development using divergence and
pressure fields
R. A. Brown, J. Patoux
R. A. Brown 2005 EGU
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Programs and Fields available onhttp//pbl.atmos.
washington.edu Questions to rabrown, neal
or jerome_at_atmos.washington.edu

• Direct PBL model PBL_LIB. (75 -00) An
  analytic solution for the PBL flow with rolls,
  U(z) f( ?P, ?To , ?Ta , ?)
• The Inverse PBL model Takes U10 field and
  calculates surface pressure field ?P (U10
  , ?To , ?Ta , ?) (1986 - 2000)
• Pressure fields directly from the PMF ?P (?o)
  along all swaths (exclude 0 - ? 5 lat.?) (2001)
  (dropped in favor of I-PBL)
• Global swath pressure fields for QuikScat swaths
  (with global I-PBL model) (2004)
• Surface stress fields from PBL_LIB corrected for
  stratification effects along all swaths (2005)

R. A. Brown 2005 EGU