SYNOPTIC OCEAN/ATMOSPHERE MEASUREMENTS IN HURRICANES ISIDORE

AND LILI

Lynn K. “Nick” Shay, Michael L. Black

MPO, RSMAS, Univ. of Miami

HRD, NOAA, AOML

ATM-97-14885, ATM-01-08218

Acknowledgments:

• Capt. Bob Maxsom and Jim McFadden (AOC) and the entire staff (pilots, engineers, technicians).

• Frank Marks (NOAA-HRD) for his continued support and HRD staff.

• Collaborators: Peter Black and Joe Cione (HRD), Bob Cheney and Paul Chang (NOAA-NESDIS), Ed Walsh (NOAA-ETL), Eric D’Asaro (UW-APL),Tom Cook (UM), S. D. Jacob (UMBC), Eric Uhlhorn (HRD), Cdr. Sean White (HRD), Scott Guhin (UM).

• Mark DeMaria (CIRA), Michelle Mainelli (NHC), Robbie Berg (NHC).

Outline:

Goals/Objectives

Introduction

Motivation (and Relevance to the JHT)

Hurricane Isidore

Hurricane Lili

Planned Analysis

• Satellite Algorithms (OHC and SHIPS)

• Ocean Mixing and Advection

• Storm Structure

Summary

Goal and Objectives:

Long-term goal of the research is to understand the role of the upper ocean on hurricane intensity changes. Specific research objectives are:

• Examine the roles of vertical current shears and horizontal advection of currents on the ocean heat content variability, and mixing processes;

• Improve satellite algorithms in estimating heat content relative to in situ measurements (AX…, floats,) and;

• Document the corresponding atmospheric structure of the storm and its intensity change.

Motivation: Hurricane Opal

Gulf (left) Versus Eddy (right) Profiles:

Pre/Post Opal Images: (SHA,SST)

CTD ProfilesCaribbean (Eddy) versus Gulf

Hurricane Isidore Flights: N42 Ocean Winds with Dr. Paul Chang (NOAA-NESDIS)

• 18 Sep N43: Pre-storm (W. Caribbean).

• 19 Sep N42:In-Storm; N43:Pre-storm (Gulf).

• 21 Sep 2 P3s: In Storm.

• 22 Sep 2 P3s: In Storm Yucatan Landfall.

• 23 Sep N43: Post Storm.

• 25 Sep 2-P3s: Landfall.

• 17 -24 Sep 8 G-IV.

IsidoreTrack Guidance

TD10 (Isidore): Caribbean

42/43 Isidore In Storm: Gulf of Mexico

SST (left panels) and OHC (right panels) for Pre-Isidore (upper) and Post-Isidore (lower) Relative to Storm Intensity (SSTs processed by RSMAS Remote Sensing Laboratory).

Hurricane Isidore Pre-Storm, Storm, Post-Storm:AXCP/AXCTD/AXBTs

Hurricane Isidore Radar Image: 21 Sept

Hurricane Isidore Radar Image: 22 Sept.

HYCOM Derived- Mixed Layer Temperatures:

10 Sept 02

• North Atlantic 32S-70N

• 1/12 o Grid Spacing.

• 6-hourly NOGAPS on monthly climatology ECMWF.

• Data assimilation (O.-M. Smedstad) SSH from radar altimeters.

• http://hycom.rsmas.miami.edu (E. Chassignet).

HYCOM Derived- Pre and Post Isidore Mixed Layer Temperatures:

10 and 25 Sept 02

Hurricane Lili Flights: N42 Ocean Winds

• 29 Sep N42:In Storm; N43: Pre-storm (N.W. Caribbean).

• 30 Sep 2 P3s: In Storm.

• 1-2 Oct N43: In Storm (Gulf).

• 2 Oct N42: In Storm.

• 3 Oct 2-P3s: Landfall.

• 4 Oct N43: Post Storm.

• 28 Sept - 3 Oct G-IV: 7 Missions.

Lili Track Guidance

43 Lili In Storm: Gulf of Mexico

SST (left panels) and OHC (right panels) for Pre-Lili (upper) and Post-Lili (lower)Relative to Storm Intensity.(SSTs processed by RSMAS Remote Sensing Laboratory).

GPS Deployments:

Isidore• 19 Sept:42-21/23 Car.• 21 Sept:42-28/28 Gulf• 21 Sept:43-28/30 Gulf• 23 Sept:43-17/20 Gulf• Total: 94/101• Success ~93%

Lili• 29 Sept:43 22/22 Car• 30 Sept:42 15/15 Car• 30 Sept:43 12/17 Car• 02 Oct:43 39/45 Gulf• 02 Oct:42 34/41 Gulf• 04 Oct:43 14/14 Gulf• Total: 136/154• Success~ 88%

Hurricane Lili Pre-Storm, Storm, Post-Storm:AXCP/AXCTD/AXBTs

Hurricane Lili Radar Image: 30 Sept.

Hurricane Lili Radar Image: 02 Oct.

Hurricane Lili Radar Image: 03 Oct. Landfall

Hurricane Lili Post-Storm AXCP Transect at 2Rmax

Hurricane Lili Storm GPS Transect (Less Height-Averaged Wind)

Surface Winds and Rain Rate from the SFMR(E. Uhlhorn)

Directional Wave Spectra In Hurricane Bonnie:

(Courtesy of E. Walsh)

Gaspar

PWP

KPP

MY 2.5

Results from Gilbert at 2Rmax for TKE Mixing Parameterizations from HYCOM:Gaspar (blue), KPP (green), MY 2.5 (red), and PWP(cyan)

Improvement of Satellite Fields For OHC Estimation:

Satellite-Derived OHC from radar altimeters:

• Seasonal Climatology;

• SSTs (Blended 7-Day Composites);

• Processed Radar Altimetry (T/P, ERS-2, GFO);

• 2 Layer Model.

Improvements:

• In Situ Data from Moorings/Floats/BTs………

• Daily SSTs (surface boundary condition)

• Monthly Climatology

Daily OHC Input Into SHIPS For Forecasting at NHC.

OHC (Leipper and Volgenau, 1972)

Q x y t c Tdz

Q x y t c SST

T

d

c

o p

s p

p

( , , )

( , , ) (

,

,

,

.

1

2 1

1

26 C) d

where:

is the density structure (T,S)

is the temperature difference relative to 26 C

is the depth of the 26 C isotherm,

is the density of the upper layer and

is specific heat capacity of sea water

26 C

26 C

OHC Comparisons Between Satellite and In Situ Data

TOPEX/Blended Fields

Observed Versus Satellite Inferred OHC From 2000

Hurricane Bret (1999): Heat Content Change and Isopycnal Displacement

OHC Based on Daily SST and a 7-Day Reynolds SST Composite After Lili.

PS-OHC C-OHC SST12 6.2 4.5 5.324 8.4 6.6 6.536 12.1 9.4 8.248 16.2 11.4 10.460 19.9 13.3 12.472 27.9 15.2 14.6

0

10

20

30

12 24 36 48 60 72Forecast Interval (hr)

Var

ian

ce E

xpla

ined

(%

)

PS-OHC

C-OHC

SST

Individual Correlation Results

(1997-2001 Sample)

3-D Atmospheric and Oceanic Structure relative to the depth of the OML observed during EPIC (NSF/NOAA)

Summary:

Unique opportunity (ocean/atmosphere data sets) to sort out the contributions to Isidore and Lili intensity change.

Envision observational, empirical, analytical, and numerical approaches

Improve satellite algorithms for OHC/SHIPS Forecasting of TC Intensity in support of the Joint Hurricane Testbed.

Document storm structure and relationships to interface processes.

Excellent Teamwork Between NSF and NOAA.

Aircraft are good platforms to conduct mesoscale to regional scale oceanographic studies ( e.g. EPIC).