12月28日(木)神戸大学
神戸大学CPSセミナー

T-PARCII航空機を用いた台風LANの観測
Aircraft observation of typhoon Lan (2017)－T-PARCII project－
Kazuhisa Tsuboki1
研究参画者・協力者
山田広幸3, 伊藤耕介3, 大東忠保5, 長浜則夫2, 清水健作2,篠田太郎1,
高橋暢宏1, 民田晴也1, 久島萌人1,山口宗彦4, 中澤哲夫4
1名古屋大学宇宙地球環境研究所・2明星電気・3琉球大学理学部・4気象研究所・５京都大学防災研究所

Schematic representation of tropical cyclone

出典：わかる！取り組む！ 災害と防災４,豪雨・台風, 帝国書院, 2017年

If tropical cyclone is in steady state, Eq. (1) will become

コリオリ力

遠心力

気圧傾度力

This balance equation is referred to as the “gradientwind balance”. Basic state of a tropical cyclone isapproximated by the gradient wind balance as wellas the “hydrostatic balance” asUsing the gradient balance equation, Eq. (1) and thehydrostatic balance equation, Eq. (2), the thermal windbalance equation is obtained as,

The inner core structure of tropical cyclone
Hawkins and Rubsam (1968)

Warm core structure above thetropical cyclone center.
Jordan (1961)

The lower part of the center is moist
and the relative humidity decreases
with height.
Shea and Gray (1973)
Gray and Shea (1973)

They hypothesized that the warm
core is caused by diabatic heating of
the descending motion in the eye.

By Hawkins and Rubsam (1968)

Structure of tropical cyclone
Eye wall and spiral rainbands
tornadoes

Maximum
wind speed
Property of tropical cyclones

Intensity: central pressure / max. wind speed
Size：radius of 15m/s wind area
TrackMovement speed
Number (genesis, approach, landing)Typhoons are the most devastating weather system.
Violent wind and heavy rainfall associated with a typhoon cause
huge disaster in East Asia including Japan.
Payment of insurance due to disasters in JapanNo.

DisasterRegion

Year/Month10^8¥1

TY #19All Japan

Sept. 1991

5,680

2

TY #18All Japan

Sept. 2004

3,874

3

snowstorm

KantoFeb. 2014

3,224

4

TY #18

Kyushu, W. J.

Sept. 1999

3,147

5

TY #7

Kinki

Sept. 1998

1,599

6

TY #15

KyushuAug. 2015

1,410

7

TY #23

Western Japan

Oct. 2004

1,380

8

TY #13

N. Kyushu

Sept. 2006

1,320

9

TY #16All Japan

Aug. 2004

1,210

10

TY #15

Shizuoka

Sept. 2011

1,123

Flooding Kinu River on Sept. 20, 2015
A present disaster in JapanA future disaster in Japan

From The General Insurance Association of Japan
http://www.sonpo.or.jp/archive/statistics/disaster/Typhoons are still the largest cause of natural
disaster in Japan.
After supertyphoon Haiyan in Nov. 2013

Increase of typhoon risk in mid-latitude regions
The location of typhoon maximum
intensity is migrating northward with time.
北半球

The thick and red lines indicate thatwind speed is larger than 67m/s.

南半球
1980

Owing to the climate change, a supertyphoon
is projected to reach the main islands ofJapan with keeping supertyphoon intensity

2000

Kossin et al. (2014), Nature2015

Tsuboki et al. (2015), GeophysicalResearch Letters

Annualnumberthe JMANumber
ofoftyphoonstrongest category of typhoon These results raise great concern regarding future change in typhoon intensity in thewestern North Pacific.
 However, the historical data of typhoon include large uncertainty.
 In particular, intensity of intense typhoons includes large error after the termination of thetyphoon reconnaissance by the US aircraft in 1987.
 In fact, the annual number of the JMA-strongest category of typhoon (10 min. averaged
sustained wind is 54 m/s or more) shows large difference between JMA and JTWC.

US JTWCJMA-RSMC

No in-situ observation by an aircraft makes it unknown which is better estimation of intensity;
JMA or JTWC.

Problem in typhoon intensity prediction
Error of track

Error of intensity(Ito 2016, SOLA)In the last 25 years, track prediction has been improved while intensity notimproved.
For accurate and quantitative prediction of typhoon intensity; High resolution: 2km at least to resolve inner core process of tropical
cyclones (e.g. Hill and Lackmann 2011).
 Non-hydrostatic, cloud-resolving model without convective parameterization.
 Cloud microphysics, PBL model, Ocean model.
 And in-situ observation data.

科研費基盤研究Ｓ：

研究課題名：「豪雨と暴風をもたらす台風の力学的・熱力学的・雲物理学的構造の量的解析」
科研費基盤研究Ｓによる台風の航空機観測計画：T-PARCII(Tropical cyclones-Pacific Asian Research Campaign for Improvement of Intensity
estimations/forecasts)
目標：● 非常に強い台風、可能であればsupertyphoon (スーパー台風)の眼の壁雲の周辺にドロップゾンデを投下する観測を実施したい。
＝＞そのような強い台風が観測域に都合よく来るのか？来たとしてもそのような強い台風を航空機で観測できるだろうか？
● 台風の航空機観測の先進国である台湾と共同観測を実施したい。
＝＞単独観測さえ難しいのに、国際協調観測が可能か？
● 台風の東側の水蒸気フラックス観測を実施したい（研究所リーダーシップ経費による）＝＞そのような都合のよい場所に台風が来るだろうか？来たとしても､本州の近くでドロップゾンデが投下できるだろうか？

Diamond Air Services (DAS) will operate the Gulfstream II aircraft for the project.
DAS is located in the Nagoya City Airport which is close to Nagoya University.

 The period of the research is 5 years; from 2016-2020.
 The Gulf Stream II aircraft will be used for dropsonde observation surrounding atyphoon (similar to DOTSTAR in Taiwan).
 A test flight was made on July 27, 2017 to the north of the Noto Peninsula .
 Typhoon observations will be made for the 4 years; 2017-2020. Once or twiceflights a year because the budget is limited.
 The main target area of observation is the south of Okinawa.
 Dropsonde data is planned to transmit to GTS in real-time.
 We hope that T-PARCII cooperates with Taiwan CWB observation.
Taiwan obsevation

Japanese aircraft

Wu et al. (2005, BAMS)

Japan obs.

Newly developed dual two-channel receiver of dropsonde in GII(Meisei electric Co and Nagoya University)Newly developed dropsonde(Meisei electric Co and Nagoya University)

Dropsonde newly developed by Meisei Electric Co.
Specification
Type nameAccuracyin Lab.

Sensor TypeiMDS-17
Temperature± 0.5 deg C

Humidity± 5% RH

Pressure±1 hPaWind Speed± 0.2 m/s

Wind Dir.

± 5 degree

Temperature

Thermistor

Humidity

Capacitive

Pressure

SiliconWindGPSWeight

110 g
7cm φ x 28 cm

Dimension
Battery

CR123 x 1

Terminal spd
Transmitter

Approximately 13 m/s
Modulation

1200 BPS FSKPower100 mW

Freq. Step

100 kHz

Freq. Band

400.1- 406.0

Observation areas of dropsondeBy Prof. Yamada (U of Ryukyus)

JTWC 20171021 06UTC: Supertyphoon LAN (2017)

Typhoon LAN（T1721) JMA forecast at 06 JST 21 Oct., 2017

Typhoon LAN (2017) [best track]

台風LAN (2017)の特徴
 JMA:超大型・非常に強い
 JTWC: supertyphoon Rapid intensification
 100 kt =51m/s =58m/s(1min)JMAのRSMCのベストトラックの風速と気圧の関係をA-H(1977)と比較したもの

Flight pass of GII ferry from Nagoya-Komaki to Kagoshima

Flight pass of observation from Kagoshima to Kagoshima

Flight pass of observation from Kagoshima to Nagoya-KomakiBy Prof. Yamada (U of Ryukyus)

By Prof. Yamada (U of Ryukyus)

By Prof. Yamada (U of Ryukyus)

From: Peter Black - NOAA Affiliate
Date: Sun, 22 Oct 2017 19:30:50 -0700
Subject: Re: [Tropical-storms] Fwd: [T-PARCII-obs:0218] Re:[T-PARCII-advisory-board:0027] Re: dropsonde observation to typhoon Lan
To: Kazuhisa Tsuboki

Dear Tsuboki-sanThere is nothing so exciting in this world as flying into
the eye of a major hurricane. It is another world that
opens up as you penetrate from turbulence and darkness
into the calm, clear eye like the curtain opening on thestage of a famous play. This is such a spectacular andmagical place. ・・・・・
Again I congratulate you and your team. ・・・・

科研費基盤研究Ｓによる台風の航空機観測計画：T-PARCII(Tropical cyclones-Pacific Asian Research Campaign for Improvement of Intensity
estimations/forecasts)：

今年度の達成点：● 非常に強い台風、可能であればsupertyphoon (スーパー台風)の眼の壁雲の周辺にドロップゾンデを投下する観測を実施したい。
＝＞達成：スーパー台風で超大型の台風（日本に多くの被害）の観測を実施。
● 台風の航空機観測の先進国である台湾と共同観測を実施したい。
＝＞達成：台湾と共同観測を実施。日本は06UTC, 21, 00UTC 22, 台湾12 UTC 21,Sept. 2017の観測を実施。
● さらに眼の中の観測を実施：21日に2回、22日に1回眼に突入。この想定外のプラスアルファの成果が得られた。
● 台風の東側の水蒸気フラックス観測を実施したい（研究所長リーダーシップ経費による）＝＞達成：22日、鹿児島から小牧空港への帰還飛行において、非常に強い台風で超大型の台風の東側でドロップゾンデ観測を実施。

今後の予定航空機GIIからGIVへの機種変更？
2018年度：SATREPS (研究代表者：高橋幸弘教授（北海道大学）)との協調観測。Philippines
領域から沖縄領域にかけての台風観測2018年度末：科研費基盤研究S中間評価
2019年度：未定
2020年度：PRECIP (PI: M. Bell (CSU))との協調観測。南西諸島・台湾領域での観測

台風研究と航空機観測のロードマップ
航空機観測
台風予測
国際協力

次申請の基盤研究(S)
気象学会の大型研究

気象学会の大型研究

 台風の航空機観測のパイロット研究 台風の航空機観測技
術の高度化

台風、豪雨、エアロゾル、温室効果気体の航空機観測技術の確立

台風の現業観測・監視

航空機観測の入力による台風予測の改善

航空機観測と数値予報の双方向通信による台風予測

現業的航空機観測による台風の双方向通信による予測

台湾との共同観測

台湾・韓国・香港との共同観測

東アジア地域の国々との国際協力による台風の監視と予測

実施中の基盤研究(S)ガルフストリームII

2016年

ガルフストリームIV

2020年

MRJ

2025年

名古屋大学宇宙地球環境研究所の飛翔体観測推進センターは国内の航空機観測の中核的役割を担う