Taiwan Typhoon and Flood Research Institute,
National Applied Research Laboratories
11F., No.97, Sec. 1, Roosevelt Rd., Zhongzheng Dist., Taipei
City 10093, Taiwan (R.O.C.)
http://www.ttfri.narl.org.tw/eng/index.html

OutlineTaiwan Typhoon and Flood Research Institute(TTFRI), one of ten members in National Applied
Research Laboratories (NARLabs), wasestablished in 2011 (Figure 1). The mission at
TTFRI is to advance prediction techniques for
typhoons and floods, and to serve as a platform
for bridging the gap between academia, industry,and government in order to benefit the publicusers. TTFRI combines theories, observations,and models, with particular emphasis on
developing core techniques for typhoon forecasts
and hydrological applications. Further, it assists
the national meteorological and hydrologicalservices and the national disaster reduction
operation.

Research Achievements
Numerical Weather Prediction TTFRI’s research uses cutting-edge techniques in data
assimilation, physical parameterization, and ensemble forecasts to develop numerical models
suitable for the complicated terrain of Taiwan that improve typhoon forecasts. In cooperation withthe Central Weather Bureau (CWB), academia, and research institutes in Taiwan and the UnitedStates, TTFRI’s major research achievements are as follows: (i) development of the Taiwan
cooperative precipitation ensemble forecast experiment (TAPEX) which provides 72-hour rainfall
forecasts during typhoon warning periods (Figure 2); (ii) development of data assimilation
technologies from GPS RO data which are used to improve weather forecasts (Figure 3); and (iii)establishment of advanced numerical weather models such as the Model for Prediction AcrossScales (MPAS) which generates long-range typhoon and seasonal rainfall forecasts (Figure 4).
TTFRI provides the forecast results to government agencies and helps them make efficientdecisions during disasters and for future water resources management.

Advanced Observation Facilities To provide a better data set for hydro-meteorologicalresearch, TTFRI has deployed and developed many observation facilities and advancedtechniques. For example, an advanced monitoring
network was implemented in the southwestern part of
Taiwan and includes a transportable C-bandpolarimetric radar (Figure 5), a wind profiler, a S-band
vertically pointing radar, disdrometers, flux towers andflow gauges. The Cband radar was installedin the Jilai mountainarea to improve rainfall
estimation in thiscomplex terrain. TheJilai mountain area isnear the location wherethe devastatinglandslide occurred dueto heavy rainfall during Typhoon Morakot in 2009. The radar needed
to be carefully situated such that the terrain did not block the path of
the radar’s beam. Site-specific sampling strategies may be required
to avoid beam blockage and to obtain a better observation. In
addition, TTFRI develops radar-based data assimilation techniques(e.g., 3D-Var and 4D-Var) to improve typhoon and rainfall forecasts(Figure 6). All of the collected observation data and techniques canbe used to improve the accuracy of weather forecasting and toreduce damage from disasters.

Disaster-related Forecasts Hydro-meteorological modeling techniques, which unify mesoscaleprecipitations and surface inundations, are developed by TTFRI to help improve the effectivenessof disaster prediction and to provide better early warning information. Using above mentioned
observations as model input, TTFRI integrates atmospheric and hydrologic models to provide
disaster-related forecasts for authorized users to access the forecasts through a hydrometeorological service platform (Figure 7). The platform is updated with the latest modeling results
every six hours. To date, there are more than 80 universities, research institutes, and disaster relief
agencies accessing the information when an extreme event happens.

Figure 7: TTFRI’s integrated researches and service platform

Challenges
A lack of observation data is always an issue that will have an impact on the accuracy of forecasts,
but it is especially a challenge to obtain correct and timely observation data during extreme events
such as typhoons and floods. To mitigate the issue, TTFRI is developing an advanced monitoring
network that integrates ground-based observing facilities (e.g., Jilai weather radar and windprofiler), and dropsonde and aerosonde observations (Figure 8). The network is being designed toenhance the understanding of the convective structure of extreme weather events, including
typhoon, Mei-Yu, and mesoscale convective systems. The network was initiated in 2014 and will
be completed in 2016. Once complete, the obtained observation data will be used to improve theforecast accuracy and strengthen disaster preparedness.

Figure 8: TTFRI work with government agencies to develop direct typhoon observation techniques

TTFRI has the responsibility to develop key technologies to observe, analyze, simulate, andforecast typhoons and floods, and to enhance the interdisciplinary hydro-meteorology research. Inaddition, TTFRI applies the technology and research to support the national meteorological andhydrological services and the national disaster reduction operation. To meet those needs, aresearch roadmap from 2013 to 2019 was developed and is shown in Figure 9. Four priorities formore effective disaster preparedness and mitigation in the future were identified as follows:
1. Emphasize on advanced observation techniques for extreme events such as typhoons andfloods to improve forecast accuracy
2. Establish a service platform to effectively provide information to decision-makers about the riskof the disasters
3. Implement interdisciplinary approaches that combine efforts in technological innovation,applications, governances, and education
4. Strengthen transnational corporations among researchers of research institutes which areinvolved in disaster prevention and risk management

Figure 9: TTFRI’s research roadmap from 2013 to 2019