Typhoon Committee Research Articles

A Review on the Long Term Variations of Tropical Cyclone Activity in the Typhoon Committee Region

ABSTRACT A review on the long term variations of tropical cyclone (TC) activity in the Typhoon Committee region was conducted based on the assessments of IPCC, IWTC and ESCAP/WMO Typhoon Committee and a number of recent publications. The results reveal strong inter-annual and inter-decadal variations in the TC activity over the western North Pacific (WNP). Analysis of available TC data since 1950s indicates that most of the TC datasets depict a decreasing trend, and some statistically significant, in the annual number of TCs and typhoons in the WNP. For TC intensity, differences in TC databases for the WNP do not allow a convincing detection of a long term trend in this basin. Climate model projections suggest a noticeable decrease in the frequency of the WNP TCs in the 21st century. Some of the model simulations also report an increase in the number of intense TCs and the TC potential intensity in the WNP in a warmer climate. Looking forward, data homogeneity in TC databases and uncertainties in model simulation are two main hurdles hindering the determination of the past and future trends of TC activity in this basin. Inter-agency co-operations are urgently required to improve the homogeneity and consistency of TC databases in the WNP. Continuous research would also be needed to further improve our understanding of the influence of natural variability and anthropogenic warming on the TC activity in the WNP.

Tropical Cyclone Information Provided by the Rsmc Tokyo - Typhoon Center

ABSTRACT The RSMC Tokyo - Typhoon Center provides the ESCAP/WMO Typhoon Committee Members with tropical cyclone (TC) information to support their disaster mitigation activities. Good knowledge and use of the information lead to appropriate and effective TC monitoring and warnings. Progress and future plans of TC information and products provided by the Center are presented.

Recent Progress in Urban Flood Risk Management in the Typhoon Committee Area

ABSTRACT The typhoon region is urbanizing rapidly with the increasing trend of population and economy. Fast urban development has also brought many potential troubles, and urban flooding is one of the most serious. Many aspects of urban areas are vulnerable to flood disasters and climate change. How to minimize losses caused by urban floods and harmonize relationship between floods and socio-economic development has been a significant problem that governments and international organizations work on. In recent years, risk management ideas have been introduced into flood management in the Typhoon Committee Area (TCA). This paper presents a brief review of urban flood issues and flood management in the TCA, and identifies good practices and research progress of urban flood risk management from the model cities study. In addition, some ideas about the improvement of urban flood risk management are also discussed in the paper.

Operational Tropical Cyclone Forecast Verification Practice in the Western North Pacific Region

ABSTRACT This paper summarizes results of a survey of the operational status of tropical cyclone (TC) forecast verification in the western North Pacific region, covering the Members of the ESCAP/WMO Typhoon Committee, RSMC Tokyo - Typhoon Center, and JTWC. Results of the survey indicate that significant efforts have been focused on the verification of TC forecast guidance by operational forecast agencies in the region, either individually or through international cooperation. A variety of TC forecast verification products are available to the forecasters in either real time or in post-season through multiple means, with the main focus on the deterministic track and intensity forecasts. Only a few verification products are available for probabilistic forecasts. Verification of TC precipitation and high wind forecasts are also lacking sufficient attention in the region. It would be helpful in the future to focus more attention toward these aspects and incorporate methods that will provide a greater depth of information regarding the TC forecast performance.

Brief Introduction to Synergized Standard Operating Procedures for Coastal Multi-Hazards Early Warning System

ABSTRACT The most countries surrounding the Indian Ocean as well as Southeast Asian countries do not have operational experience in handling a combination of tsunami and other coastal hazard early warning systems. The challenge faced by warning providers, media, disaster managers, and coastal communities is in understanding the similarities and differences among different coastal hazards and the characteristics of the early warnings that are issued. There is a strong need to create synergies among different types of coastal hazard early warnings by reviewing the relevant existing standard operating procedures. These synergies can be achieved through identifying specific gaps and needs for making the existing early warning systems fully operational for the use in multi-hazards context. The project of Synergized Standard Operating Procedures for Coastal Multi-Hazards Early Warning System (SSOP) was proposed by Typhoon Committee Secretariat with the objectives of developing the SSOP Manual/Handbook and establishing the cooperation mechanism on coastal multi-hazard early warning among the target countries. The project will mainly focus on the meteorological and hydrological services for affected areas which become more vulnerable to natural disasters after tsunami and other costal disasters. The synergized standard operating procedure should be easier understandable and interpretable for decision makers, forecasters and dwellers.

Activities of the ESCAP/WMO Typhoon Committee Regarding Sediment-Related Disaster Prevention Using Non-Structural Measures, Based on Japa Nese SABO Technology

ABSTRACT In the project activities of the ESCAP/WMO Typhoon Committee (TC), the National institute for Land and Infrastructure Management (NILIM), the SABO (Erosion and Sediment Control) Department of the Ministry of Land, Infrastructure, Transport and Tourism (MLIT), and the SABO and Landslide Technical Center (STC) implemented two projects: Disaster Forecasting Warning System (2002-2008) and Project on Hazard Mapping for Sediment-related Disasters (2009-2012). The aim of these projects was to distribute Japanese SABO technology, particularly non-structural measures, among TC members. This report presents the concepts and methods related to non-structural measures for sediment-related disaster prevention based on Japanese SABO technology, the contents of the two projects' activities, the preparation of early warning information, the creation of a hazard map, and the preparation of an integrated system for resident evacuation.

North Western Pacific Tropical Cyclone Ensemble Forecast Project

ABSTRACT The WMO/TCP and WWRP launched the North Western Pacific Tropical Cyclone Ensemble Forecast Project (NWP-TCEFP) in 2009 to explore the utility of ensemble forecasts, including multi-model ensemble forecasts of TCs, and to promote such products for operational TC forecasting. Operational global medium-range ensembles, which have been exchanged in real-time in a CXML format under the initiative of the WMO GIFS-TIGGE Working Group, have been used to create ensemble products of TC tracks that were used by the Typhoon Committee Members and forecasters participating in the SWFDP in Southeast Asia through a password-protected website developed and maintained by the JMA. In some cases many or all of the ensembles have simultaneously predicted small or large ensemble spreads in TC tracks. The implication is that multi-model ensemble products provide forecasters with additional information on forecast certainty or uncertainty and thus increase the level of confidence in the forecasts. Another important outcome of the project was the responses to surveys conducted by the WMO/TCP and WWRP and also by the WMO GIFS-TIGGE Working Group. The responses confirmed that ESCAP/WMO Typhoon Committee Members have routinely accessed the website and have recognized the usefulness of the ensemble products available on the website for operational TC forecasting.

A Challenge of the Experiment on Typhoon Intensity Change in Coastal Area

ABSTRACT The Experiment on Typhoon Intensity Change in Coastal Area (EXOTICCA) was proposed by the China Meteorological Administration (CMA) and Hong Kong Observatory (HKO) and endorsed by the ESCAP/WMO Typhoon Committee (TC). The major goals and objectives of the EXOTICCA are: 1) to conduct the field campaigns on the intensity and structural characteristics of the target offshore and landfall tropical cyclones by employing integrated and novel observation techniques, and 2) to conduct demonstration research on the utilization of the synergized field observation data with the aim of deepening the understanding of the mechanism of structure and intensity changes, to improve the relevant capability of operational analysis, numerical weather prediction (NWP) models forecast, reliable storm surge and flooding and associated risk assessment. The Organizational structure and implementation schedule etc. are also introduced in this paper.

The Chronicle of Events of the ESCAP/WMO Typhoon Committee From 1968 to 2017

The Chronicle of Events of the ESCAP/WMO Typhoon Committee From 1968 to 2017

New technology and experiment of rocket dropsondes for typhoon observation

This study presents a new technique for typhoon observations that is based on dropsondes launched by long-distance rockets instead of research aircraft. This technology was developed by Shanghai Typhoon Institute of China Meteorological Administration in collaboration with China Aerospace Science and Industry Corporation in the past three years. On October 3, 2015, this meteorological rocket was successfully launched for the first time into an offshore strong typhoon (Mujigae, 2015) located east of Hainan Island. Four dropsondes were subsequently deployed within 6 min by the rocket when it flew into the inner core of Mujigae from the launching city, Wanning in Hainan Province that was located 200 km away from the storm. Real-time data from the dropsondes were sent back to the observation station on the ground. The detailed profiles of wind, temperature and humidity were obtained, showing high quality according to comparisons with the near collocated GPS radio-sondes data. These dropsonde profiles captured some fine-scale wind structure in the Typhoon Mujigae with may be related to large eddies. This field experiment described in this study implied a potential use of this new dropsondes-deployment technique for future TC research and operation. The success of the field campaign with rocket-carrying dropsondes could provide an effective and direct observation technique for rapid and accurate access to the fine-scale structure of typhoon interior (different areas, but at the same time), and provide a new way to achieve the typhoon targeting sensitivity analysis related to forecasting. Showing the advantages of long-range, high-quality and high-precision, this new technique, when deployed from high altitudes could improve TC model initial condition and provide accurate estimates of storm intensity of offshore typhoons, resulting in improved operational TC track and intensity predictions, as proved by previous studies that used aircraft-deployed dropsondes. Under the support of the Economic and Social Commission for Asia and the Pacific (ESCAP) and World Meteorology Organization (WMO) Typhoon Committee, STI together with HKO organized the Experiment of Typhoon Intensity Change in Coastal Area (EXOTICCA) as an international cooperation project. This project carried out field experiments using rocket-platform sounding detection technology and other new typhoon field detection utilities. In the coming few years, EXOTICCA will also implement observations using man aircraft, unman aircraft, long-distance rockets and GPS sounding in South China Sea. It is believed that the new rocket deployment technology presented in this study when used in future field experiment will improve the track and intensity forecasts of typhoons.

近年の台風委員会（Typhoon Committee） の活動

近年の台風委員会（Typhoon Committee） の活動

신경망 모델과 확률 모델의 풍수해 예측성능 비교

최근 급증하는 기상이변 및 기후온난화 현상은 풍수로 인한 피해를 더욱 가속시키고 있어 풍수해 발생가능성을 미리 예측하여 선제적으로 대응할 방안 마련이 필요하다. 재난 재해의 위험성 분석은 주로 확률 통계기법에 기반한 수식모델 연구가 주류를 이루고 있고 소방방재청 국립방재연구소에서 구축한 태풍위원회 재해정보시스템(TCDIS: Typhoon Committee Disaster Information System) 또한 지역별 풍수해 위험성 분석에 확률모델을 활용하고 있다. 본 논문에서는 경험적 패턴인식에 탁월한 성능을 가진 신경망 알고리즘을 활용하여 개발한 풍수해 예측모델을 소개하고 이 모델과 TCDIS의 KDF 확률밀도함수를 이용한 풍수해 예측모델의 성능 비교 결과를 제시하여 기존 TCDIS의 위험성 분석기능에 신경망 모델을 적용함으로써 시스템의 강건성과 예측 정확도 향상이 가능함을 보이고자 한다. Storm and flood such as torrential rains and major typhoons has often caused damages on a large scale in Korea and damages from storm and flood have been increasing by climate change and warming. Therefore, it is an essential work to maneuver preemptively against risks and damages from storm and flood by predicting the possibility and scale of the disaster. Generally the research on numerical model based on statistical methods, the KDF model of TCDIS developed by NIDP, for analyzing and predicting disaster risks and damages has been mainstreamed. In this paper, we introduced the model for prediction of damage cost from storm and flood by the neural network algorithm which outstandingly implements the pattern recognition. Also, we compared the performance of the neural network model with that of KDF model of TCDIS. We come to the conclusion that the robustness and accuracy of prediction of damage cost on TCDIS will increase by adapting the neural network model rather than the KDF model.

International Experiments to Study Tropical Cyclones in the Western North Pacific

Four separate (but coincident in time) field experiments to study tropical cyclones in the western North Pacific area will be carried out during August/September 1990 by the United States, the Economic and Social Commission for Asia and the Pacific/World Meteorological Organization (ESCAP/WMO) Typhoon Committee, the USSR, and by Taiwanese scientists. The objective of the U.S. experiment is to improve basic understanding of tropical cyclone motion. The focus of the ESCAP/WMO Typhoon Committee experiment is to improve operational track prediction. A multi-ship and aircraft expedition is planned by the USSR to understand the effects of the ocean inhomogeneities on tropical cyclones, and the response of the ocean to typhoon passage. Researchers in Taiwan will organize special observations of typhoons approaching Taiwan to understand the wind and precipitation distributions. The combined observations from these experiments should result in a comprehensive dataset for the study of western Pacific tropical cyclones.