DYNAMO—DYNAmics of the MJO Shipboard operation of the NASA/TOGA radar DYNAMO—DYNAmics of the MJO Shipboard operation of the NASA/TOGA radar Photo courtesy of T. Lang September 2011 – February 2102

NASA TOGA radar

Moum et al SST pattern quite interesting! Ocean really never “recovered” after MJO2. 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> T air ) and reduction in solar insolation. This is part of the story! SST AIR Strong westerlies in MJO2

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 weaker? Shallow thermocline in Indian O. allows access to cooler water. 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 weaker? Shallow thermocline in Indian O. allows access to cooler water. Moum et al. 2014

Surface wind stress

Daily Evolution: Convective Population 1. In phase: RH, Rainrate, Strat. Rain. 2. In phase: SST, Lightning, CAPE. Role of Aerosols?

A little background… Z K dp Oklahoma K dp proportional to mass content and mass-weighted oblateness ratio Based on computations of Z and Kdp from DSD assumptions Based on computations of Z and Kdp from DSD assumptions 0.5 deg elevation angle deg/km Difference in H,V phase in degrees Rain K dp is a measure of the difference in wave propagation between H and V polarizations; sensitive to non-spherical particles a b 0 Differential Reflectivity Reflectivity

N-Pol in Oklahoma Results consistent with active coalescence growth and ice-based precipitation. Resulting from higher moisture contents, higher freezing level, collisional breakup, etc. N-Pol data are clearly going to help us better understand DSD variability and the physics leading to the variability. N-Pol in Oklahoma Results consistent with active coalescence growth and ice-based precipitation. Resulting from higher moisture contents, higher freezing level, collisional breakup, etc. N-Pol data are clearly going to help us better understand DSD variability and the physics leading to the variability. Colorado and “tropical” events Colorado and “tropical” events Warm rain Ice based Normalized density of points expressed as a percentage N-POL

NASA IFLOODS DEPLOYMENT INSTRUMENTATION Radars: Rain mapping, 4-D precip structure, DSD, rates NPOL S-band transportable, scanning dual-pol radar D3R radar: Dual-frequency (KA- KU), dual-polarimetric, Doppler radar. 3 Metek Micro Rain Radars (K- band), vertically pointing (one on order) Point-Network Disdrometer/Gauges: Precip character/reference 5 2D Video Disdrometers Parsivel-2 Disdrometer with MetOne 12” TB Rain Gauge 25 dual-gauge Met One TB rain gauges with soil T/Q Precipitation Video Imager (PVI) Dual-Gauge Net JW

May 2, 2013 – Cold, light rain

May 26, 2013 – Convection

26 Jan 1999 EAST case. Stronger convection, higher CAPE. 24 Feb 1999 WEST case. Lower CAPE, monsoon-like regime. EAST WEST 0 Subtle differences between East and West

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. Pretty much a tropical regime….