experiment on typhoon intensity chang in coastal area (exotica) chang in coastal area (exotica) lei...

ExExperiment periment oon n TTyphoon yphoon IIntensity ntensity

Chang in Chang in CCoastal oastal AArea (EXOTICA)rea (EXOTICA)

Lei Xiao-tuShanghai Typhoon Institute of CMA

2015.1.20 Ningbo, China

UNESCAP/WMO TC cross-cutting project:

Outline

1. Background (context)

2. Scientific issues & objectives

3. Field Campaigns & demonstrating

research

4. Strategy and management

5. Progress and future plan

RSMC Tokyo

JTWC

CMA

HKO

KMA

Time Series of the Annual Average Position Errors of Operational TC track Forecasts in NW Pacific

In general, the errors have been decreasing

(E48hr, now ~ E24hr,15yr bf )

However year-to year variations exist that are due mainly to differences in the annual number of TCs

and difficulty in forecasting TC track

In general, the errors have been decreasing

(E48hr, now ~ E24hr,15yr bf )

However year-to year variations exist that are due mainly to differences in the annual number of TCs

and difficulty in forecasting TC track

Performance in TC Track Forecasting by Global NWP

Systems

Significant prediction errors still exist and there are prediction cases

where the position error can exceed 1000 km over 3 days.

Although the theories of TC motion might have reached a satisfactory

level, our knowledge on the causes of prediction errors is still poor.

Typhoon Megi initiated at 1200 UTC 25th Oct. 2010

Observed track

Typhoon Conson initiated at 1200 UTC 12th Jul. 2010

MCGE-9 (BOM, CMA, CMC, CPTEC, ECMWF, JMA, KMA, NCEP, UKMO)

Challenges for track forecast: 1) Near coast & Landfalling

1412

1109

Challenges for track forecast: 1)Near coast & Landfalling

2009-13 NHC official track forecast error

binned by initial intensity for the Atlantic basin

The track errors averaged over the past 5 years are largest for the weakest initial intensity TCs.

Model improvements are still required with an emphasis to increase numerical track forecast skill for the weak or initial stages of TCs.

The track errors averaged over the past 5 years are largest for the weakest initial intensity TCs.

Model improvements are still required with an emphasis to increase numerical track forecast skill for the weak or initial stages of TCs.

Challenges for track forecast: 2)weak stage

NCEP-GFS

forecast tracks

From : http://tlfdp.typhoon.gov.cn

NCEP-GFS Track Error for "Fitow"

0

30

60

90

120

150

180

210

240

270

300

330

0

200

400

600

800

1000

1200

1400

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1800

2013093012UTC2013100100UTC2013100112UTC2013100200UTC2013100212UTC2013100300UTC2013100312UTC2013100400UTC2013100412UTC

120h error

Large errors

Although, considerable progress have been made in recent four years for global models, there still

are some incredible errors at long lead time levels in 2013, such as typhoon “Fitow”.

Large errors are mainly appear in the early stage of the life cycle of “Fitow”.

Initial

times

Case: large tCase: large track forecast error during the weaker stage rack forecast error during the weaker stage (“Fitow”2013)(“Fitow”2013)

Mean intensity errors in official operational forecast in

NW Pacific from (JMA,JTWC, CMA)

  24h 48h 72h 96h 120hECMWF-IFS 10.82 15.29 18.38 20.14 20.13

NCEP-GFS 7.80 10.75 12.70 13.28 13.11UKMO-MetUM 9.80 15.36 18.17 18.90 18.88

JMA-GSM 9.44 15.64 19.33

KMA-GDAPS 10.67 17.19 21.72 24.32 25.65

CMA-T639 8.43 12.04 13.80 14.49 14.19

Mean Intensity Error in 2013

(m/s)

ECMWF-IFS intensity error from 2010 to 2013The intensity forecast did not have distinct improvement in recent four years

Challenges for intensity forecast: 1 ） landfalling(weaker-before, stronger after landfall) 2 ） weak (early and ending), super typhoon, rapid change

ECMWF-IFSUKMO-MetUM NCEP-GFS JMA-GSM KMA-GDAPS CMA-T639-50

-40

-30

-20

-10

0

10

20

30

40

50 48h

Inte

nsi

ty E

rro

r (m

/s)

24h

ECMWF-IFSUKMO-MetUM NCEP-GFS JMA-GSM KMA-GDAPS CMA-T639-50

-40

-30

-20

-10

0

10

20

30

40

50

Inte

nsi

ty E

rro

r (m

/s)

ECMWF-IFSUKMO-MetUM NCEP-GFS JMA-GSM KMA-GDAPS CMA-T639-70

-60

-50

-40

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-20

-10

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70

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nsi

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rro

r (m

/s)

72h

ECMWF-IFSUKMO-MetUM NCEP-GFS JMA-GSM KMA-GDAPS CMA-T639-80

-60

-40

-20

0

20

40

60

80

Inte

nsi

ty E

rro

r (m

/s)

96h

Before landing: The forecast results of intensity were extremely weaker than OBS.

After landing: The forecast results of intensity were stronger than OBS.

The capability of intensity forecast for global model still have great room for improvement in the future.

Super-Typhoon

HAIYAN (1330)HAIYAN (1330)

Case: large iCase: large intensity forecast (“Haiyan”2013)ntensity forecast (“Haiyan”2013)

Time

T0922(NIDA)

Time

CI number

T1013(MEGI)

T1330(HAIYAN)Large difference in CI Numbers are found after Haiyan made landfall in the Philippines.

Time

•2013 11 08 00 UTC

In the weakening stage, a time lag of 12 hours is provided between T-number and CI-number because of the fact that decline of a cloud system precedes the decrease in intensity. At landing, RSMC Tokyo

decreases CI-number with the T-number without a time lag.

45th Session Final Report of TC

Paragraph 45.t:

“ WGM In conjunction with other WGs and TRCG, to take the lead in designing and formulating a tropical cyclone field experiment within the region, in particular by making use of the available opportunity in collaborating with the Southern China Monsoon Rainfall Experiment (SCMREX) planned by the WGTMR of WMO for implementation in 2013 (spin-up phase) and 2014 (field phase), and hold a small expert meeting to draft the proposal if necessary.”

Drafting Process

1st Version Draft: March 2013, on behalf of WGM, STI/CMA drafted

the 1st version of the plan. Symposium: March 2013, Chaired by Ms. JIAO Meiyan, a

coordinated meeting was held in CMA, attended by Dr. LEI Xiaotu (Chairperson of WGM), Prof. LUO Yali (Chief Scientist of SCMREX), Prof. DUAN Yihong (Chair of WMO/WGTMR).

Circulate: the 1st draft was circulated among TRCG.

Drafting Process (con.)

2nd Version Revise: April 2013

Present: May 2013, AWG small meeting-Bangkok (Jun YU)

May 2013, 8th WGDRR workshop-Seoul (Derek Leong)

October 2013, 2nd WGH workshop-Seoul (Jin ping LIU)

3rd Version Revise: November 2013 Present: December 2013, 8th IWS and 2nd TRCG Forum

4th Version Revise: January – February, 2014 Submit: February 2014, 46th Session

Topic: Intensity change (RI/RW): Weaker stage (TD RI to TS) in the coastal area of TC region Landfalling (RI & TS RW to TD)

Scientific issues: The effect of non-uniform complex surface and the sea-land-atmosphere

interaction on the boundary layer wind distribution of tropical cyclone The predictability and credibility of the prognostic of the intensity changes The impact of the intensity changes on the tidal level and the flooding in

the flood plain of this region The impact of the intensity changes on the vulnerability of the disaster of

typhoons in the Asia Pacific Region

2.1 Scientific issues

2.2 Goals and objectives

Field campaigns (target typhoon observation) 3-5 target typhoons per year Test new monitoring techniques: aircraft (drop-sound), mobile/automatic

GPS (rise-sound), buoy array,…. rocket (drop-sound) gather the comprehensive observation data related to the target typhoon

Demonstration research Improve the knowledge of abnormal intensity change (RI & RW), in

particularly, the genesis (in SCS) and disappear (after landfall)

Improve the performance of typhoon intensity determine and regional

numerical modeling

Develop the storm surge (urban city) , flooding (inland) forecasting and

damage risk estimate/forecast system

1. NWP model and EPS (3 slides)

2. Application

Consensus (1 slide)

Ensemble mean (1 slide)

3. Data assimilation

TC initialization

Data assimilation methods (1 slide)

Assimilation of satellite-based observations (2 slides)

Assimilation of aircraft-based observations (3 slides)

IWTC-8:

Three factors may be attributed to this

improvement in TC track forecasts by the NWP systems:

Field Campaigns (progress of international typhoon society)

CBLAST-LOW T-PARC/TCS-08 SPECTRUM DOTSTAR

use of advanced

instruments and equipment

on target hurricane, the

strong wind background

between the sea – air

exchange and

transmission

Using the drop sounding, rafting sounding, microwave radiometer, land-based wind profile radar, doppler wind radar, etc. Focus on the formation of tropical cyclones, strengthening, structural change, moving, degeneration and so on.

Using observation ships,

buoys, wind profile radar

sounding system, etc. in the

northwest Pacific region to

carry out the moving

characteristics under weak

environment of typhoon

For the first time in the Pacific northwest with drop sounding and aircraft detection for typhoon. 32 typhoon aircraft reconnaissance, 39 voyages since 2003. powerfully impelled the research for typhoon structure and data assimilation

26

2008/09/11 12UTC

Initial Time2008/09/11 12UTC

Special Observations (09-15UTC)Aircraft dropsondes: 24Upper soundings (vessels): 2Upper soundings (observatories):3

2008/09/11 12UTC935hPa

Impact of Special Observations for SINLAKU

9/12

9/129/12

9/11 12UTC Init

9/13

9/14

9/15

9/169/17

9/18

9/139/14

9/15

9/16

9/17

9/18

9/13

9/14

9/15

9/16

9/17

• The special observation data have a large impact on the forecast of the recurvature for Typhoon SINLAKU.

• The experiment with special observation data predicted recurvature.

Recurvature !

No Recurvature

• There was no recurvature in the experiment without special observation data.

Without Special OBS.

With Special OBS.

(2008/09/11 12UTC)

Without Special OBS.

With Special OBS.

Impact of Special Observations for SINLAKU

GSMGSM Forecast Forecast WithWith

Special ObservationSpecial Observation

Aberson (2010, MWR)

From 1997-2006:

the assimilation of the

supplementary dropwindsondes

improved NCEP GFS track

forecasts by 10-15% during the

first 60 h of the forecasts.

WMO Report: Conclusions• Observations are

important both

within and outside

the TC, varies from

case to case

• Observations

targeted in selected

areas are mostly

beneficial

• Aircraft are often

unable to cover

target areas

NOGAPS SV JMA SV

UM ETKF UK ETKF COAMPS ADJ

Targeted observations

Wu et al. (2009), Reynolds et al. (2010), Majumdar et al. (2011a),

Aberson et al. (2011), Hoover et al. (2013)

ECMWF SV

Which subset of dropwindsondes improves the ECMWF typhoon track forecast the most?

remote sensitive regions

Small improvements

imp

rove

men

t

degradation

typhoon center and core

neutral

degradationim

pro

vem

ent

typhoon vicinity

Largest improvements

degradation

imp

rove

men

t

Harnisch and Weissmann (2010, MWR)

Current status of “operational” airborne observations of TCs

DOTSTAR(NTU, CWB, TTFRI etc)

Aircraft: ASTRA SPX

Wu et al. (2005, BAMS)

Hurricane Hunters(US Air Force and NOAA)Aircraft: WC130, P-3, G-IV

Hurricane hunter association

NOAA

WC130

G-IV

P-3

AIMMS-20(Hong Kong)Aircraft: J41

Develop & refine observing technologies: Global Hawk UAS

• 282 total dropsondes deployed during more than 58 h over and near the storm

• 16 September flight plan designed and coordinated by NOAA scientists

• Multiple drops into eye and eyewall from Global Hawk 60,000 ft

• Select dropsondes suggested rapid intensification on 15 September

• Novel observations documenting storm decay over colder waters

• Dropsonde data processed in real time, transmitted to NWS gateway, and assimilated in operational WRF model

• Observations will facilitate several forecast impact studies with multiple numerical models

4 flights sampled life cycle of Edouard from tropical storm to extra-tropical transition11 September, Tropical Storm 14 September, Category 1

16 September, Category 3 18 September, Decay34

Intensity: Min. SLP Error (hPa)

HS3 drops

No drops

Bias (dash)

Sensitive regions in Nadine were often well observed by HS3 dropwindsondes

Dropwindsonde impact experiments performed for 19-28 Sep. (3 flights)

HS3 drops

No drops with synthetics

COAMPS-TC intensity and track skill are markedly improved using HS3 drops.

NASA Hurricane Severe Storm Sentinel (HS3)Impact of HS3 Dropwindsondes for Nadine (2012)

HS3 drops

No drops

HS3 Global Hawk Flight Tracks: Nadine

30 Drops

70 Drops

76 Drops

58 Drops

34 Drops

75 Drops

J. Doyle

When: September 16 and 17 2014

Where: Hurricane Edouard boundary layer inflow channel

UAS flight duration: 68 minutes

Minimum (controlled) Altitude: 400m

Maximum Wind Speed: 53kt @6m

•36

Low-level unmanned aircraft: Coyote

J. Cione

Multi-instrument coordinating

observation

(satellite, radar…

WMO network, and

dropsonde …

Multi-instrument(EXOTICA)

Area of field campaign

(EXOTICA)

S

ECMA

EXOTICA

Field Campaigns (South China Sea)

Period : Jun-Jul & Sep-Oct (2014-

2017)

Region Cover: China (Guangdong, Guangxi and

Hainan), Hong Kong/China, Macao/ China,

Philippines, Viet Nam. Focus on: genesis, rapid enhance, super-

typhoon

海上观测平台

100m 观测铁塔

北山观测站

6.5km

New instruments (South China Sea)

HKO

2.3 Field Campaigns (East China Sea)

Period : July. – Oct. (2014-2016)

Region Cover: China (Fujian, Zhejiang, Shanghai,

Jiangsu, Shandong ,Taiwan), Japan, Republic

of Korea, DPRK. Overlap with SCMREX Focus on: sudden weakening, dissipation, ET

New instruments (East China Sea)

Oil Platform (in ECS)

Requested… (TC 45th Session)

WGs - WGM (AOP10, PP1) - TRCG Members - CMA, HKO, KMA, JMA - HRD …

WGs - WGM (AOPs, WMO-FDP) - TRCG (WMO-RDP) - WGH & WGDRR (AOPs)Members - CMA, HKO, KMA,JMA, Viet Nam… - HRD…

EXOTICA (Implementation schedule)

Organization Structure On the small meeting

Planned (2014): To hold a two-day

OC meeting in Shanghai on June 30,

To established the OC (Organizing Committee) of EXOTICA

Implementation: OC meeting

conjunction with AWG meeting

Almost AWG members have not available time (during TCs season) to attend the meeting

Postpone (2015)

Surveillance flight (HKO ,

since 2012 )

Planned action of ROK in

2015-2016KMA launched the aircraft project for target observationsKMA launched the aircraft project for target observations

Since 2012, KMA has begun an aircraft launching project for the purpose of severe weather

• observation, the precipitation enhancement experiment and the characterization of the atmospheric• climate change. The aircraft will be equipped with 14 kinds of instruments, which include a dropsonde system, • glaciogenic and hygroscopic cloud seeding systems, four kinds of cloud property measurement• and atmospheric aerosol and pollutant gas monitoring systems. From 2016, KMA could carry out three dimensional target observation and the data would be • shared for domestic and international operation and research purpose.

•

Planned action of China(pilot/spin-up….)

To continue the mobile sounding (CMA) To build “National Typhoon Observing Station in East China” To pilot the un-man aircraft in ECS (S&T Ministry’s project) To pilot “Rocket sounding” in SCS & ECS (S&T Ministry’s project) To pilot “Yi-satellite buoy” in SCS (National key research program-973)

National Typhoon observing

station

National Typhoon observing

station

Mobile m

onitory system

(STI/C

MA

)

Progress (a-1)

STI/CMA

On the field campaign (mobile..)

Progress (a-2)

STI/CMA

On the field campaign (buoy array)

June-Augest,2014June-Augest,2014站位 经度 纬度 备注F1 116°00′ 19°40′

气象 +150KADCP + 自容温盐链 (15pcs) +波浪

F2 115°30′ 18°10′气象 +150KADCP + 自容温盐链 (15pcs)

F3 116°30′ 18°40′气象 +单点海流计 +直读耦合温度链 (10pcs)

F4 117°30′ 19°10′气象 +300KADCP + 自容温盐链 (15pcs) +波浪

F5 117°00′ 17°40′气象 +300KADCP + 自容温盐链 (15pcs) +波浪

M1 116°01′15″ 19°37′31″

300KADCP upward/75KADCP downward(280m)+ SEAGUARD(Meters above bottom 100m/50m/10m)+SBE37(MAB 50m/30m/10m)

M2 115°32′50″ 18°11′28″

300KADCP upward/75KADCP downward(280m)+ SEAGUARD(Meters above bottom 100m/10m)

M4 117°27′10″ 19°08′35″

300KADCP upward/75KADCP downward(160m)+ SEAGUARD(Meters above bottom 100m/10m)

M5 116°58′50″ 17°42′21″

300KADCP upward/75KADCP downward(160m)+ SEAGUARD(Meters above bottom 100m/10m)

Internet

CLS America

铱卫星

铱星浮标

Satellite buoy array: Super Typhoon(Rammasun,2014)Satellite buoy array: Super Typhoon(Rammasun,2014)

Satellite buoy array (2Satellite buoy array (2ndnd case-super typhoon Kalmaegi) case-super typhoon Kalmaegi)

56325 － 186 米 15s ？

2011080623

Upgraded GRAPES-TCM

Data Assimilation

Data Assimilation

Post Processing

Post Processing

Verification &

Assessment

Verification &

Assessment

Vortex Initializatio

n

Vortex Initializatio

n

GRAPES Meso-scale

Model

GRAPES Meso-scale

Model

Hybrid System Based on GSI

Updated dynamics &

GFS based physics

NCL-based data processing & illustration

Database techniques &conventional-special verification combined

To be consolidated into a single package

HWRF Scheme

GRAPES-TCM (Old)GRAPES-TCM(New)

GRAPES-TCM(New), July-Oct. 2014

Progress (b-1)

STI/CMA

On the field campaign (UAV-prepared)

Progress (b-2)

STI/CMA

On the field campaign (Rock dropsonde- prepared)

三沙基地

大陈岛（发射点）

作业指挥中心

万宁（发射点）

Plan in 2015

To hold the OC meeting (May, 2015, Shanghai) (May, 2015, Shanghai) for preparing the implementation (field campaign in 2015) of the experiment Establish the SSC and 3 RGs (Field Campaign, Basic Research, Typhoon

Modeling)

Confirm the tasks of participating TC Members on the field campaign in 2015

To test the field campaign by using aircraft (un/manned) drop-sounds, mobile GPS rise-sound and rocket drop-sound CMA: mobile GPS rise-sound, aircraft (unmanned), rocket drop-sound, Yi-

satellite buoys

HKO: aircraft (manned) drop-sound

Demonstration research on tropical cyclone intensity change by using target typhoon data from the field campaign (to be included in the TC Fellowship Scheme) High-resolution typhoon modeling (specially, target typhoon data assimilation)

Mechanism of target typhoon intensity change

Plan in 2015

Multi-instrument coordinating

observation

(satellite, radar…

WMO network, and

dropsonde …

Multi-instrument(EXOTICA)

WMO RDP (.or. HIWeather

Programme) ?

Welcome to join us

(EXOTICA)……

Thank you for your attention!