Serendipity

1
Serendipity the faculty or phenomenon of finding
valuable or agreeable things not sought for
R. A. Brown 2006
2
Mission statement for the scatterometer 78 We
have an instrument that can measure surface
stress (or winds near the surface) -- the most
important forcing of the oceanic mixed
layer. Or (might have been) We have an
instrument that provides backscatter from a 25-km
patch of ocean proportional to waves in the 1-6
cm.
R. A. Brown 2006
3
1 9 7 8
Scatterometer Product from Space
Surface WIND vectors
R. A. Brown 2006
4
2 0 0 5
Frontogenesis info
Near real time pressure maps for forecasts
Scatterometer Products from Space
Ocean Fronts
WIND vectors
Atmospheric Fronts
Nonlinear model proof
Daily Global Marine Surface Pressure Fields
Land Vegetation
Pack Ice location, concentration, thickness
Storms location, Strength
Antarctic ice flow movement
Mean PBL temperature
Mean PBL stratification
Surface stress vector
R. A. Brown 2006
5
Mission statement for a lidar We have an
instrument that can measure winds in the
troposphere -- the most important dependent
variable in the equations of motion --- essential
to good weather climate modelling Or We have
an instrument that provides doppler signal return
from atmospheric aerosols between the satellite
and surface.
R. A. Brown 2006
6
Lidar PBL possibilities
GCM updates
Wind vectors
Air-surface Fluxes
PBL turbulence spectrum
Rolls
PBL dynamics and air-surface fluxes
Aerosol statistics
Inversion height
Surface characteristics
R. A. Brown 2006
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Hazards of taking measurements in the Rolls

e.g. a dropsonde profile
Hodograph from center zone
Hodograph from convergent zone
1-km
The OLE winds
Station A
3
2 - 5 km
U
2
The Mean Wind
Z/?
1
Station B
V
Mean Flow Hodograph
RABrown 2004
8
Principle of The Red Queen

• Named after the chess piece in Alice in
  Wonderland, --- she moves faster faster, in
  more complicated ways, yet Nothing
  Significant Changes.
• Used in Evolution and Biology, mainly to describe
  the predator-prey relationship.
• I note today that the principle seems to apply to
  modelling the turbulent PBL? (fantastically
  complicated turbulence models yet no better
  weather climate models)

R. A. Brown 2005 EMS
9
Surface Pressures from Space
R. A. Brown 2005 AGU
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R. A. Brown 2005 AGU
R. A. Brown 2004 EGU
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Dashed ECMWF Solid UW-Quikscat
The UW PBL Model is now global and operational
R. A. Brown 2005 AGU
12
Pressure Fields used in NCEP Forecast Analyses
R. A. Brown 2005 AGU
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a
b
996
991
999
996
OPC Sfc Analysis and IR Satellite Image 10 Jan
2005 0600 UTC
GFS Sfc Analysis 10 Jan 2005 0600 UTC
c
d
984
982
UWPBL 10 Jan 2005 0600 UTC
QuikSCAT 10 Jan 2005 0709 UTC
14
Some Conclusions
R. A. Brown 2005 AGU
15

• Surface pressures as surface truth yield high
  wind predictions. This suggests that the global
  climatology surface wind record is too low by 10
  20.
• Brown, R.A., Lixin Zeng, 2001 Comparison
  of Planetary Boundary Layer Model Winds with
  Dropwindsonde Observations in Tropical Cyclones,
  J. Applied Meteor., 40, 10, 1718-1723 Foster
  Brown, 1994, On Large-scale PBL Modelling
  Surface Wind and Latent Heat Flux Comparisons,
  The Global Atmos.-Ocean System, 2, 199-219.

R. A. Brown 2005 AGU
16

• The dynamics of the typical PBL revealed in
  remote sensing data indicate that K-theory in the
  PBL models is physically incorrect. This will
  mean revision of all GCM PBL models as resolution
  increases.
• Brown, R.A., 2001 On Satellite
  Scatterometer Model functions, J. Geophys. Res.,
  Atmospheres, 105, n23, 29,195-29,205 Patoux,
  J. and R.A. Brown, 2001 Spectral Analysis of
  QuikSCAT Surface Winds and Two-Dimensional
  Turbulence, J. Geophys. Res., 106, D20,
  23,995-24,005 Patoux, J. and R.A. Brown,
  2002 A Gradient Wind Correction for Surface
  Pressure Fields Retrieved from Scatterometer
  Winds, Jn. Applied Meteor., Vol. 41, No. 2, pp
  133-143 R.A. Brown P. Mourad, 1990 A
  Model for K-Theory in a Multi-Scale Large Eddy
  Environment, AMS Preprint of Symposium on
  Turbulence and Diffusion, Riso, Denmark. On the
  Use of Exchange Coefficients and Organized Large
  Scale Eddies in Modeling Turbulent Flows. Bound.
  Layer Meteor., 20, 111-116, 1981.

R. A. Brown 2005 AGU
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• There is evidence from the satellite data
  that the secondary flow characteristics of the
  nonlinear PBL solution (with Rolls or Coherent
  Structures) are present more often than not over
  the worlds oceans. An understanding of this
  solution contributes to the basic understanding
  of PBL modelling, data analysis and air-sea
  fluxes.
• Refs
• Brown, R.A., 2002 Scaling Effects in Remote
  Sensing Applications and the Case of Organized
  Large Eddies, Canadian Jn. Remote Sensing, 28,
  340-345 Levy G., 2001, Boundary Layer Roll
  Statistics from SAR. Geophysical Research
  Letters. 28(10),1993-1995.

R. A. Brown 2005 EMS
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• These data allow us to build a climatology of
  primary and secondary cyclones (in particular
  their kinematics as revealed by scatterometer
  winds) e.g. test the hypotheses that explosive
  frontal storm development may have predictors
  (e.g. upper level vorticity or surface vorticity
  anomolies) and the possibility that the strength
  of storms and fronts is increasing due to global
  warming.
• ReferencesPatoux, J. and R.A. Brown, 2002
  Spectral Analysis of QuikSCAT Surface Winds and
  Two-Dimensional Turbulence, J. Geophys. Res.,
  106, D20, 23,995-24,005 Brown, R.A., 1998
  Global High Wind Deficiency in Modeling, Chapter
  in Remote sensing of the Pacific Ocean by
  Satellites, p69-77, Southwood Press Pty Limited,
  Marrickville Australia, pp. 454.

R. A. Brown 2005 EMS
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For Lidar, there is an Opportunity

• There exist no satellite determined winds in the
  PBL (there is a scatterometer, but it is due to
  expire theres a radiometer, but it is limited)
• There are very few in situe direct measurements
  of winds in the PBL
• Sonde and buoy point wind measurements incur
  large errors due to turbulence OLE
• The successful parameterization of fluxes
  (air-surface) requires good boundary layer winds
• Climate Analyses are being made on extremely
  poor data
• There are no USA wind satellites planned to
  launch

R. A. Brown 1/2006
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Programs and Fields available onhttp//pbl.atmos.
washington.edu Questions to rabrown, ralph
or jerome _at_atmos.washington.edu

• Direct PBL model PBL_LIB. (75 -05) 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 - 2005)
• 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) (2005)
• Surface stress fields from PBL_LIB corrected for
  stratification effects along all swaths (2006)

R. A. Brown 2006