DYNAMO—DYNAmics of the MJO Shipboard operation of the NASA/TOGA radar. Photo courtesy of T. Lang. September 2011 – February 2102. NASA TOGA radar. Strong westerlies in MJO2. SST pattern quite interesting! Ocean really never “ recovered ” after MJO2. SST. AIR.
DYNAMO—DYNAmics of the MJO
Shipboard operation of the NASA/TOGA radar
Photo courtesy of T. Lang
September 2011 – February 2102
NASA TOGA radar
Prolonged periods (> 24 hours) of
negative net flux rare in tropics. These
are periods when ocean cools through
loss of latent and sensible heat (SST> Tair)
and reduction in solar insolation. This is part
of the story!
Moum et al. 2014
Yoshida-Wyrtki jet, westerly surface current.
Mixing promoted by strong vertical shear brings cool, salty water to the surface.
Shear induced mixing is significant component for lowering the SST’s,
in addition to surface fluxes/insolation. MJO2 resulted in a major cooling of the upper ocean. Did this have an impact on MJO3, which was much
Shallow thermocline in Indian O. allows access to cooler water.
Moum et al. 2014
Surface wind stress
Daily Evolution: Convective Population
1. In phase:
2. In phase:
Role of Aerosols?
Kdp proportional to mass content and
mass-weighted oblateness ratio
Kdp is a measure of the difference in wave propagation between H and V polarizations; sensitive to non-spherical particles
0.5 deg elevation angle
Based on computations
of Z and Kdp from DSD
deg/km Difference in H,V phase in degrees
Normalized density of points expressed as a percentage
Colorado and “tropical”
N-Pol in Oklahoma
Results consistent with
active coalescence growth
and ice-based precipitation.
Resulting from higher
moisture contents, higher
freezing level, collisional
N-Pol data are clearly going
to help us better understand
DSD variability and the physics leading to the variability.
24 Feb 1999
26 Jan 1999 EAST case.
Pretty much a
KDOX 10/28/2012: Merger of Sandy's outer bands with N/S oriented front. This confluence caused significant precipitation along the western shore of the Chesapeake Bay.