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In response to the impacts of extreme precipitation on human or natural systems under climate change, the development of climate risk assessment approach is a crucial task. In this paper, a novel risk assessing approach based on a climate risk assessment framework with copula-based approaches is proposed. Firstly, extreme precipitation indices (EPIs) and their marginal distributions are estimated for historical and future periods. Next, the joint probability distributions of extreme precipitation are constructed by copula methods and tested by goodness-of-fit indices. The future joint probabilities and joint return periods (JRPs) of the EPIs are then evaluated. Finally, change rates of JRPs for future periods are estimated to assess climate risk with the quantitative data of exposure and vulnerability of a protected target. An actual application in Taiwan Island is successfully conducted for climate risk assessment with the impacts of extreme precipitation. The results indicate that most of regions in Taiwan Island might have higher potential climate risk under different scenarios in the future. The future joint probabilities of precipitation extremes might cause the high risk of landslide and flood disasters in the mountainous area, and of inundation in the plain area. In sum, the proposed climate risk assessing approach is expected to be useful for assisting decision makers to draft adaptation strategies and face high risk of the possible occurrence of natural disasters. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to propose and test a moderated mediation model examining the relationships among ethical work climate, organizational identification, leader-member-exchange (LMX) and organizational citizenship behavior (OCB). Design/methodology/approach: Numerous regression analyses were performed using PROCESS (version 2.13), a macro for SPSS developed by Hayes (2017) to test this moderated mediation model. Findings: The analytical results showed that organizational identification mediates the positive relationship between an ethical work climate and OCB. The analytical results also showed that LMX moderates the direct effect of ethical work climate on organizational identification and that LMX also moderates the indirect effect of ethical work climate on OCB via organizational identification. Practical implications: This study provides numerous valuable implications for hotels to develop effective strategies to promote employees' OCB and improve their organizational identification. Originality/value: This study was the first attempt to propose and test a moderated mediation model that explores the relationships among ethical work climate, organizational identification, leader-member-exchange (LMX) and OCB. [ABSTRACT FROM AUTHOR]

Taiwan and Philippine (TWPH) (117°E-129°E, 5°N-26°N) is a region with most frequent and intense tropical cyclone (TC) influence in the world. This paper documents the climatology and variability of TWPH TC activity with specific attention to the difference in the TCs formed over the western North Pacific (WNP) and over the South China Sea (SCS). The spatial characteristics of TWPH TCs are analyzed based on the accumulated cyclone kinetic energy (ACE) in four sub-areas where distinctly different TC seasonality and variability is found. Different from over the broad Northwest Pacific Basin (0°-60°N, 100°E-180°) where the WNP-born TC frequency dropped sharply in late-1990s and the SCS-born TC frequency slightly increased in mid-1990s, over TWPH three distinct epochs are identified. A weakvariability epoch occurred during 1979-1996, a persistent low-ACE epoch during 1997-2002, and a more variable epoch during 2003-2018. The second epoch is most noteworthy. The unusually weak TC activity during this period in particular over the Philippines was associated with anomalously strong anticyclone over the SCS and the Philippine Sea during the East Asian summer monsoon season. The strong anticyclonic circulation appeared as a descending leg of the enhanced East Asian summer monsoon during summer (July-September). During autumn and early winter (September-December) the Philippine Sea anticyclone was interpreted as the descending Rossby wave response to the suppressed convection over tropical western Pacific. The anomalous anticyclone strengthened the low-level confluent flow and convection over the SCS. The findings are useful to real-time TWPH TC activity monitoring and analysis. [ABSTRACT FROM AUTHOR]

Up until now montane cloud forest (MCF) in Taiwan has only been mapped for selected areas of vegetation plots. This paper presents the first comprehensive map of MCF distribution for the entire island. For its creation, a Random Forest model was trained with vegetation plots from the National Vegetation Database of Taiwan that were classified as “MCF” or “non-MCF”. This model predicted the distribution of MCF from a raster data set of parameters derived from a digital elevation model (DEM), Landsat channels and texture measures derived from them as well as ground fog frequency data derived from the Moderate Resolution Imaging Spectroradiometer. While the DEM parameters and Landsat data predicted much of the cloud forest’s location, local deviations in the altitudinal distribution of MCF linked to the monsoonal influence as well as the Massenerhebung effect (causing MCF in atypically low altitudes) were only captured once fog frequency data was included. Therefore, our study suggests that ground fog data are most useful for accurately mapping MCF. [ABSTRACT FROM AUTHOR]

This study presents the meteotsunami behavior in response to different storm types in the coasts of southern Asia-Pacific Ocean from 16 years water level records. Through the size-frequency analysis, the dangerous meteotsunami, wave height exceeding 0.3 m, can occur up to 44 events per year. Notably, during the extreme waves of the 2007 event, wave heights reached approximately 0.9-1.5 m in the Taiwan Strait and the western coastal areas of Taiwan. We have classified storms into six types by radar reflectivity images and satellite-derived precipitation. Findings indicate that predicted wave heights caused by bows and typhoons could reach hazardous magnitude of exceeding 2 m in a 100-yr interval. Spatial and temporal analysis reveals that meteotsunami occurrences are most frequent in the western regions during the winter to early spring months (December to April). Of all meteotsunami occurrences, cluster storms are identified as the most prevalent atmospheric forcing, accounting for 60% of meteostunamis. Typhoons have a 20% association with meteotsunamis along the east coasts of Taiwan during late summer to autumn. On the east coasts, typhoon type-induced events may be attributed to the combination effect of meteotsunamis and infra-gravity waves. Overall, this study provides the first comprehensive examination of meteotsunami-storm characteristics and their associated hazard risks in the coastal areas of the southern Asia-Pacific Ocean. [ABSTRACT FROM AUTHOR]

Using seismic and Chirp sonar profiles, this paper tests the hypothesis that hyperpycnal flows are the main factor controlling the formation and maintenance of the meandering Kaoping submarine canyon off SW Taiwan. Cross-section geometries, and erosional as well as depositional features vary along the canyon course. In the proximal, sinuous part of the canyon, down-cutting into the shelf strata has created a relief of 340 m. The cause of this intense erosion of the seafloor is suggested to be the frequent development of hyperpycnal flows. A seismic section across a meander in the distal part of the canyon shows levees formed by overspilled sediments at the outer bend, and a terrace characterized by relatively flat stratified facies at the inner bend. The geological setting and climatic conditions in SW Taiwan (e.g. earthquakes, typhoons, floods), as well as major river–canyon connections (for example, direct input of highly concentrated suspended sediment) would all promote hyperpycnal flow generation. This causes axial incision, canyon wall slumping, and the formation of levees by spill-over deposition in the upper reach of the Kaoping Canyon. [ABSTRACT FROM AUTHOR]

High‐resolution Taiwan Climate Change Projection Information and Adaptation Knowledge Platform (TCCIP) gridded precipitation data are used to characterize days in the Mei‐yu season with the most extreme precipitation (EP). These "EP days" are grouped into weather types based on the presence of features such as tropical cyclones (TCs) and atmospheric rivers (ARs), then analyzed from the perspective of weather type frequency and synoptic changes. During the 1979–2019 period, EP days associated with ARs were associated with significant increasing trends in season‐total precipitation. These AR‐related precipitation increases are due to four events in 2005, 2006, 2012, and 2017 which had long duration and unusually intense precipitation, and which were anomalous even within the longer 1960–2019 time period. Meanwhile, TC‐related EP days contribute less precipitation than they did in the 1980s due to decreased frequency of TCs on EP days and in the Mei‐yu season climatology. Over the 1979–2019 period, the AR‐related and TC‐related trends combine to produce EP increases in western Taiwan and decreases in eastern Taiwan. Mei‐yu season southwesterly integrated vapor transport (IVT), wind speed, and specific humidity have all increased in association with these extreme events. Low‐level winds appear to the primary factor influencing the IVT increase, with increased moisture also contributing. The wind trends are consistent with climatological pressure increases south of Taiwan and decreases over the East Asian landmass, which facilitate a strengthened circulation in a corridor extending from the southern China coastline over Taiwan during this season. [ABSTRACT FROM AUTHOR]

Heavy rainfall is a challenge to forecast due to the variety of rainfall intensities and durations across a wide spectrum of high‐impact storm types. In this study, we analyze extreme storms in Tropical and Subtropical East Asia, a moisture‐rich environment with complex terrain and oceanic regions. The Tropical Rainfall Measuring Mission's Precipitation Radar is utilized to characterize the frequency and rainfall intensity of four extreme storm types. Extreme storms producing heavy precipitation are categorized into four types: deep convective cores (DCCs), deepwide convective cores (DWCCs), wide convective cores (WCCs), and broad stratiforms regions (BSRs). DCCs and DWCCs occur more frequently and produce stronger rain intensities over land compared to those over ocean. However, WCCs and BSRs occur more frequently over oceans, especially in association with the Meiyu front season and climatological progression in the northern subregions. Although the Convective Cores show higher rain intensities than the BSRs, they show lower volumetric rain rate due to their comparatively smaller horizontal area. An ingredients‐based framework is applied to find key similarities across the different heavy rainfall‐producing storms near Taiwan using ERA5 reanalysis. The analysis shows that the broader systems (i.e., WCCs and BSRs) are associated with larger in area and longer timescales of vertical moisture flux and low‐level wind shear that support the development of the horizontally large, organized storms. Smaller DCCs do not show strong vertical moisture flux on the spatial scales resolved by the reanalysis, suggesting their more local nature and less meso‐ or synoptic scale support. Plain Language Summary: Heavy rainfall is a challenge to forecast due to the variety of rainfall intensities and durations across a wide spectrum of high‐impact storm types. In this study, we analyze extreme storms in Tropical and Subtropical East Asia (TSEA), a moisture‐rich environment with complex terrain and oceanic regions. Observations from the first satellite precipitation radar are used to characterize the nature of extreme storms. Results show that deep convective storms occur more frequently over land, while the wide convective storms and the broad stratiform regions occur more frequently over oceans, especially in association with the Meiyu front (pre‐East Asian monsoon season) in northern TSEA. Broad stratiform regions can produce a larger total rainfall amount compared to the convective rain categories because of larger areas. A goal of this study is to identify similar key ingredients across different extreme storm types near Taiwan. Analysis shows that the broader storms are associated with moisture in larger areas and on longer timescales, and also low‐level wind shear that supports the development of the large, organized storms. Smaller deep convective storms do not show strong moisture signals in coarse‐scale environmental analysis, suggesting that this storm type might need more small‐scale moisture support. Key Points: The spatio‐temporal and rain frequency of extreme storm types in Tropical and Subtropical East Asia is documentedBroad stratiform environments, for example, in Meiyu Front, require a longer and larger moisture build‐upSmaller convective systems require spatially smaller diurnal vertical moisture flux and convergence [ABSTRACT FROM AUTHOR]

Abstract: Traditional benchmarking of building energy performance usually starts by considering a wide range of different factors and giving these factors different weights to help reach one general indicator measuring a building’s overall energy performance. For obtaining more specific information in building energy management performance, this paper proposes an adjustment to the traditional approach by using climate classification and data envelopment analysis (DEA). The study first adopts cluster analysis to classify the evaluated buildings into different climate clusters. Secondly, scale factors are identified by regression analysis. DEA is then employed to assess the energy management efficiency of the evaluated buildings. The samples of 122 office buildings in Taiwan in summer are classified into three climate clusters (warm and long rain hour, hot and middle rain hour, and hot and short rain hour). Research results indicate that the average indicators of energy management performance in each of the three climate clusters are 0.5, 0.56, and 0.56 respectively. The lower value indicator of energy management performance, resulted from the comparison between the energy consumption of the evaluated building and the minimum energy consumption among buildings in the same scale and similar climate conditions, indicates a more potential in energy saving. [Copyright &y& Elsevier]

We identified four climatic stages between 6.2 and 1.3 cal kyr before present (BP) based on pollen and charcoal concentrations by high‐resolution Accelerated mass spectrometer (AMS) 14C‐dated sediment profile from Taiwan's Toushe Basin. From 6.2 to 4.6 cal kyr BP, the region was warm‐wet with infrequent wildfires and dominant subtropical evergreen broad‐leaved forests. The climate was cooler‐drier from 4.6 to 3.0 cal kyr BP, with a decline in forest and increased fire frequency. From 3.0 to 2.1 cal kyr BP, climate further cooled and dried, with the development of alpine meadows and higher fire frequency. The region became warmer and wetter from 2.1 to 1.3 cal kyr BP, accompanied by forest recovery. Climatic changes were linked to changes in East Asia Summer Monsoon intensity, which is mainly controlled by solar radiation. Wildfires were likely controlled by precipitation variability that is influenced by East Asia Summer Monsoon and El Niño–Southern Oscillation. Toushe Basin experienced drought conditions and frequent wildfires during the El Niño years. Plain Language Summary: The purpose of our study is to reveal the relationship between paleoclimate, vegetation, and wildfire. The study area is located in the Toushe Basin, central Taiwan. Through palynological and charcoal analysis, the vegetation, climate, and wildfire history of the past 6,000 to 1,000 years in the study area were reconstructed. The study found that after 4,600 years, the East Asian summer monsoon continued to weaken until approximately 2,000 years ago, during which time the climate was dry and cool, and wildfires were frequent. In addition, it is found that the climate in this region is mainly controlled by the changes in solar radiation. The cycle of climate change coincides with that of solar activity. In El Niño years, the Toushe Basin was dry and frequent wildfires occurred. Key Points: Four climatic stages identified between 6.2 and 1.3 cal kyr BP based on pollen and charcoal concentrationsClimatic changes were linked to changes in East Asia Summer Monsoon intensity, which is mainly controlled by solar radiationThe Toushe Basin experienced drought conditions and frequent paleowildfires during the El Niño years [ABSTRACT FROM AUTHOR]

This research develops a team-level model based on transactive memory theory to analyze how teams achieve excellent performance by managing innovative climate and politics. In the model, team performance relates to innovative climate positively and politics negatively through the full mediation of transactive memory systems (TMS). Meanwhile, the effects of innovative climate and politics on TMS are moderated by perceived meaningfulness. Its empirical results reveal that team performance indirectly relates to innovative climate and politics via the full mediation of TMS. Besides, the positive relationship between innovative climate and TMS is moderated by perceived meaningfulness, such that the relationship is stronger when perceived meaningfulness is higher. Empirical testing of our model using the data collected from team personnel in Taiwan confirmed the applicability of the transactive memory theory among work teams. Last, managerial implications and research limitations are provided. [ABSTRACT FROM AUTHOR]

Taiwan's most significant natural hazards are caused by hydrological extremes resulting from excessive precipitation. The threat of extreme precipitation is posed by several different types of weather patterns that affect Taiwan. This study examined the bi‐decadal changes in rainfall by defining an extreme precipitation occurrence (EPO) for a range of event durations from 1 to 24 hr. Three major weather types affecting EPO in Taiwan were identified from 1993 to 2015: the front type consisting of either a frontal zone or convective systems developing with an apparent Meiyu cloudband, diurnal rainfall events when no apparent synoptic features are present, and a tropical cyclone (TC) type according to the maximum sustained wind radius of a TC. Results show that TC‐type events have the greatest overall contribution to EPO at longer (>6 hr) durations. Diurnal/afternoon convection events contribute most to the shorter (<3 hr) duration EPO, while frontal/Meiyu systems prevail in the medium (3–6 hr) duration. EPO of almost all durations have experienced an increase, with the 3‐ and 12‐hr EPO having increased by 4.6 days each over the 23 years. However, apparent decadal‐scale variability exists in these EPO associated with the decreasing tendency of EPO after the mid‐2000s, particularly the longer duration (>6 hr) EPO associated with the TC‐type events in summer. The distinction between EPO trends for the entire island of Taiwan and for the Taipei metropolitan area alone (northern Taiwan, population of 7 million) were compared, and an intriguing interannual variation is reported in the TC‐type EPO associated with the TC season 1 year to a year and half just before an El Niño–Southern Oscillation event. The analysis here provides refined statistical distributions of extreme rainfall, and these can contribute to the revision of governmental definitions for weather disasters that are used in mitigation and response strategies. [ABSTRACT FROM AUTHOR]

According to the latest Taiwan's energy plan, nuclear power that provides approximately 16% of total electricity will be replaced by renewable energy sources by 2025. Wind power is of particular interest because Taiwan's maritime climate and constant monsoons make it a feasible alternative that potentially generate a considerable amount of electricity. To better understand how wind power can provide stable electricity output and sequester CO2 emissions, this study employs the Weibull distribution with a threshold regression model to estimate the electricity potential for 370 scheduled wind farm sites and refine electricity estimation according to observed data from all existing wind farms. The results show that, compared to the theoretical estimation models, our proposed refinement method can, in average, reduce estimating error by 87%. The results indicate that construction of all scheduled sites are not a cost-effective approach, and the government may focus on construction of stations that can generate electricity of more than 12 million kWh per year, if capital rationing do exist. Our insightful results thus convey constructive suggestions regarding sites selection, stability of wind speed, and electricity potential of each site, all of which can be helpful in decision making. It is also noteworthy to point out that unless future climate is far deviated from the observed data, wind power can be an effective substitute of nuclear power. [ABSTRACT FROM AUTHOR]

East Asia emits more greenhouse gases into the atmosphere than any other region, yet little is known about attitudes towards climate change in this region. A cross-sectional survey investigating climate change knowledge, concern and behavior change was administered to 1118 university students at nine universities across Taiwan in June 2016. Knowledge was assessed with a 15-item quiz while concern and behavioral change were self-reported on 5-point Likert scales. The relationship of these three variables with various socio-demographic variables was investigated through Kruskal-Wallis tests and ordinal logistic regressions. Knowledge was homogeneous by region but differed sharply by socioeconomic position. Concern appears high by international standards, with 65% reporting being “somewhat concerned” and 28% being “very concerned,” while climate change denial was negligible. Students expressing greater concern were more likely to be from eastern and southern Taiwan, regions more vulnerable to extreme weather events. However, these high concern levels did not translate into action, as only 38% of respondents reported “some” and 11% reported “very much” behavioral change in response to climate change. Higher levels of behavioral change were reported by students expressing greater concern and students with lower levels of climate change knowledge. In contrast with studies of Western societies, our findings suggest an East Asian model in which the conflict between economic growth and the environment is playing out in different ways, such that the crucial need is for policy leadership and not more education. [ABSTRACT FROM AUTHOR]

Motivated by the increasing thermal load in urban environment, this work established Urban Climatic map (UCmap) focusing on thermal environment issues based on urban development factors, e.g., land cover and building characteristics, representing thermal load of human body and ventilation path in the urban structures. In the established process of UCmap in this work, Tainan city, which is a highly developed city in southern Taiwan, is selected as the research area. A 50-m resolution grid is used to capture urban development factors and the climate data based on 1 year of mobile and fix-point measurements, from which the thermal load and the wind environment map are constructed. The results herein reveal that a higher urban development level is associated with a higher thermal load, and similar areas are more likely than others to suffer from an extreme thermal load and low wind pass conditions. Open and sparse low-rise buildings constitute the most appropriate urban characteristics for urban built environment in Tainan. By the simple approach of establishing UCmap, the microclimate condition and development intensity of regions can be easily detected and linked, for example the compact high-rise areas should be limited by floor area ratio in order to prevent the formation of hot spots. The government, urban planners, and architects without a meteorological background can efficiently obtain climate information by way of mapping the certain area, and making regulations to mitigate the growing problem of thermal stress and urban heat island. [ABSTRACT FROM AUTHOR]

Mean radiant temperature ( T) values were calculated and compared to each other in Taiwan based on the six-directional and globe techniques. In the case of the six-directional technique (measurements with pyranometers and pyrgeometers), two different T values were calculated: one representing the radiation load on a standing man [ T(st)] and the other which refers to a spherical reference shape [ T(sp)]. Moreover, T( T) was obtained through the globe thermometer technique applying the standard black globe. Comparing T values based on the six-directional technique but with different reference shapes revealed that the difference was always in the +/−5 °C domain. Of the cases, 75 % fell into the +/−5 °C Delta Tmrt range when we compared different techniques with similar reference shapes [ T(sp) and T( T)] and only 69 % when we compared the different techniques with different reference shapes [ T(st) and T( T)]. Based on easily accessible factors, simple correction functions were determined to make the T( T) values of already existing outdoor thermal comfort databases comparable with other databases which involve sixdirectional T. The corrections were conducted directly between the T( T) and T(sp) values and also indirectly, i.e., by using the values of T to reduce the differences between T(sp) and T( T). Both correction methods resulted in considerable improvement and reduced the differences between the T(sp) and the T( T) values. However, validations with an independent database from Hungary revealed that it is not suggested to apply the correction functions under totally different background climate conditions. [ABSTRACT FROM AUTHOR]

In this study, an ensemble typhoon quantitative precipitation forecast (ETQPF) model was developed to provide typhoon rainfall forecasts for Taiwan. The ETQPF rainfall forecast is obtained by averaging the pick-out cases, which are screened using certain criterion based on given typhoon tracks from an ensemble prediction system (EPS). Therefore, the ETQPF model resembles a climatology model. However, the ETQPF model uses the quantitative precipitation forecasts (QPFs) from an EPS instead of historical rainfall observations. Two typhoon cases, Fanapi (2010) and Megi (2010), are used to evaluate the ETQPF model performance. The results show that the rainfall forecast from the ETQPF model, which is qualitatively compared and quantitatively verified, provides reasonable typhoon rainfall forecasts and is valuable for real-time operational applications. By applying the forecast track to the ETQPF model, better track forecasts lead to better ETQPF rainfall forecasts. Moreover, the ETQPF model provides the 'scenario' of the typhoon QPFs according to the uncertainty of the forecast tracks. Such a scenario analysis can provide valuable information for risk assessment and decision making in disaster prevention and reduction. Deficiencies of the ETQPF model are also presented, including that the average over the pick-out case usually offsets the extremes and reduces the maximum ETQPF rainfall, the underprediction is especially noticeable for weak phase-locked rainfall systems, and the ETQPF rainfall error is related to the model bias. Therefore, reducing model bias is an important issue in further improving the ETQPF model performance. [ABSTRACT FROM AUTHOR]

To quantify the effects of long-term climate change on typhoon rainfall near Taiwan, cloud-resolving simulations of Typhoon (TY) Sinlaku and TY Jangmi, both in September 2008, are performed and compared with sensitivity tests where these same typhoons are placed in the climate background of 1950-69, which is slightly cooler and drier compared to the modern climate of 1990-2009 computed using NCEP-NCAR reanalysis data. Using this strategy, largely consistent responses are found in the model although only two cases are studied. In control experiments, both modern-day typhoons yield more rainfall than their counterpart in the sensitivity test using past climate, by about 5%-6% at 200-500 km from the center for Sinlaku and roughly 4%-7% within 300 km of Jangmi, throughout much of the periods simulated. In both cases, the frequency of more-intense rainfall (20 to >50 mm h−1) also increases by about 5%-25% and the increase tends to be larger toward higher rain rates. Results from the water budget analysis, again quite consistent between the two cases, indicate that the increased rainfall from the typhoons in the modern climate is attributable to both a moister environment (by 2.5%-4%) as well as, on average, a more active secondary circulation of the storm. Thus, a changing climate may already have had a discernible impact on TC rainfall near Taiwan. While an overall increase in TC rainfall of roughly 5% may not seem large, it is certainly not insignificant considering that the long-term trend observed in the past 40-50 yr, whatever the causes might be, may continue for many decades in the foreseeable future. [ABSTRACT FROM AUTHOR]

Data assimilation is important for the spatial analysis of small regions with complex terrain and diverse climates and for interpolation among observations. A data assimilation method incorporating observations, coarse-grid re-analysis data and physiographical features is demonstrated to generate high-resolution temperature data for small islands such as Taiwan. The method is also able to weigh physiographic and anthropogenic factors. Among the spatial factors, the orographic effect is the dominating factor and the lapse rate varies seasonally. Population density is significantly related to temperature, which may correspond to the urban heat-island (UHI) effect. It is also shown that an anthropogenic factor could be used with this interpolation method to explain the details of the temperature variation. The data assimilation model provides an opportunity to assess the extent to which simple statistical regression equations, calibrated from natural variability, can reproduce climate changes driven by land effects without considering a complex climate model. Copyright © 2012 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

This study is focused on the modification of a typhoon rainfall climatological model, by using the dataset up to 2006 and including data collected from rain gauge stations established after the 921 earthquake (1999). Subsequently, the climatology rainfall models for westward- and northward-moving typhoons are established by using the typhoon track classification from the Central Weather Bureau. These models are also evaluated and examined using dependent cases collected between 1989 and 2006 and independent cases collected from 2007 to 2011. For the dependent cases, the average total rainfall at all rain gauge stations forecasted using the climatology rainfall models for westward- (WTRCM12) and northward-moving (N-TRCM12) typhoons is superior to that obtained using the original climatological model (TRCM06). Model W-TRCM12 significantly improves the precipitation underestimation of model TRCM06. The independent cases show that model W-TRCM12 provides better accumulated rainfall forecasts and distributions than model TRCM06. A climatological model for accompanied northeastern monsoons (A-TRCM12) for special typhoon types has also been established. The current ATRCM12 model only contains five historical cases and various typhoon combinations can cause precipitation in different regions. Therefore, precipitation is likely to be signifi- cantly overestimated and high false alarm ratios are likely to occur in specific regions. For example, model A-TRCM12 significantly overestimates the rainfall forecast for Typhoon Mitag, an independent case from 2007. However, it has a higher probability of detection than model TRCM06. From a disaster prevention perspective, a high probability of detection is much more important than a high false alarm ratio. The modified models can contribute significantly to operational forecast. [ABSTRACT FROM AUTHOR]

Using rain gauge data during 134 mei-yu frontal cases in May-June 1991-2006, a rainfall climatology in relation to the positions of fronts every 0.5° in Taiwan is obtained, showing widespread precipitation with maxima over windward mountain slopes associated with frontal passages. For six major river basins, rainfall characteristics and synoptic factors are further analyzed to build a conceptual climatology model for short-term quantitative precipitation forecasts (QPFs). The four basins in central-southern Taiwan exhibit increased heavy-rainfall frequencies (>25%) roughly from 2° south to 1° north of the front, while the two basins in northern Taiwan have lower frequencies with different characteristics mainly due to the differences in their topography. The synoptic factors in the checklist employed by the Central Weather Bureau and important to heavy rainfall are identified for each of the six basins through statistical tests and their threat score (TS). These factors include those related to mei-yu fronts, low-level jets and moisture, upper-level divergence-diffluence, and short-wave troughs. A conceptual climatology model that uses both synoptic and probability forecasting guidance is developed, and in practice the average rainfall climatology is replaced by one obtained for heavy-rainfall periods if either of the two guidance schemes indicates heavy-rainfall possibility. This model for 0-6- and 0-12-h QPFs is also evaluated for its usefulness using cases during the 2007-08 seasons. With typical TSs of 0.2-0.3 (for heavy rainfall), this approach outperforms simple climatology in all six basins especially toward higher thresholds (about 20-50 mm) and for 12-h events, where it also shows advantages over model QPFs in southern Taiwan. Thus, the model can provide useful information for operational use. [ABSTRACT FROM AUTHOR]

The article presents a study that investigates the impact of climate change on rainfall, evapotranspiration, and discharge in northern Taiwan. This analysis shows that rainfall and discharge will be increased during the wet season and decreased during the dry season. Furthermore, evapotranspiration will be increased in the whole year except in November and December.

Bayesian analysis is applied to detect changepoints in the time series of seasonal typhoon counts in the vicinity of Taiwan. An abrupt shift in the typhoon count series occurs in 2000. On average, 3.3 typhoons per year have been noted before 2000 (1970–99), with the rate increasing to 5.7 typhoons per year since 2000 (2000–06). This abrupt change is consistent with a northward shift of the typhoon track over the western North Pacific–East Asian region and an increase of typhoon frequency over the Taiwan–East China Sea region. The northward shift of the typhoon track tends to be associated with typhoon-enhancing environmental conditions over the western North Pacific, namely, the weakening of the western North Pacific subtropical high, the strengthening of the Asian summer monsoon trough, and the enhanced positive vorticity anomalies in the lower troposphere. Based on observational analysis and model simulations, warm sea surface temperature anomalies over the equatorial western and central Pacific appear to be a major factor contributing to a northward-shifted typhoon track. [ABSTRACT FROM AUTHOR]

Three years’ worth of radar reflectivity data from four radars in an area of complex terrain (Taiwan) from 2005 to 2007 were analyzed and a reflectivity climatology was developed. The climatology was applied in the construction of new hybrid scans to minimize the impacts of ground clutter and beam blockages. The reflectivity climatology showed significant seasonal variations and captured distributions of ground/sea clutters, beam blockages, and anomalous propagations in addition to precipitation systems in the radar domains. By comparing the reflectivity climatology with gauge observations, it was found that 15 (20) dBZ was a good approximation for rain/no-rain segregation during cool (warm) seasons. Comparisons between the standard (i.e., based on terrain and scan strategies only with the assumption of standard propagations) and nonstandard (i.e., standard plus the clutter and blockage mitigation using the reflectivity climatology) hybrid scans showed that the former did not accurately reflect the clutter and blockage distributions in the real atmosphere. The application of the reflectivity climatology was shown to significantly reduce the impacts of clutter and blockages and provided improved radar quantitative precipitation estimates (QPEs) in the complex terrain. [ABSTRACT FROM AUTHOR]

The tropical rainfall potential (TRaP) technique is a simple concept that serves as a useful tool for forecasters in predicting the accumulated rainfall from typhoons. This research seeks to propose an algorithm for improving the accuracy of the results retrieved from the TRaP technique by taking into account the terrain’s influence on a typhoon’s rainfall pattern over Taiwan. The climatological percentages of the accumulated rainfall in Taiwan for six different typhoon tracks were established via statistical methods. By using the rainfall percentages with the original TRaP technique, results showed that the original TRaP technique could retrieve a graphical representation of the accumulated rainfall from typhoons for both oceans and flat land areas. When factoring in Taiwan’s terrain, the accuracy in a typhoon’s accumulated rainfall estimation is seen to further improve. [ABSTRACT FROM AUTHOR]

Taiwan, an island of approximately 36000 km2 area, includes stunning diversity in both habitat and biota because of its transitional position. Where the Tropic of Cancer cuts across the middle of the island and the east Philippine plate subducts into the Eurasia plate, the landscape and weather are extremely congenial for a highly diverse biota to develop over the years in Taiwan. Such a natural endowment has enabled diverse habitats for wildlife to evolve. Insects are especially abundant in Taiwan. For example, about 400 species of butterflies occur in Taiwan. Export of aesthetically attractive insects, such as butterflies and beetles, is an ongoing key industry in Taiwan right from the early to middle 20th century. As the economic preferences moved towards high technology with a concurrent understanding of biological diversity and the concept of conservation grew strong, use of insect materials have currently moved towards education and entertainment. Besides the exhibition of traditional methods of insect collection, several newly developed insectaria are presently integrated into Taiwanese museums, zoos, and university departments using modern technology for displaying activities of live insects. Summer camps offer plentiful opportunities for children to learn about insects. Volunteers, with appropriate research skills and extensive scientific knowledge are involved in these exhibitions. Rearing of “pet” insects is popular and, consequently, enabled the growth of some specific supply companies. Traditionally, insect resources are used in many aspects, such as in medicine and food and extraction of insect products such as silk and honey; occasionally some of the insects are useful as even game animals. Fighting crickets provide entertainment, and occasionally used in gambling as well. Insects provide diverse and abundant resources and are an excellent material deserved for better exploration in many aspects. [ABSTRACT FROM AUTHOR]

1. We used high-frequency in situ dissolved oxygen measurements to investigate the seasonal variability and factors regulating metabolism in a subtropical alpine lake in Taiwan between May 2004 and October 2005, specifically exploring how the typhoon season (from June or July to October) affects lake metabolism. 2. Gross primary production (GPP) and ecosystem respiration ( R) both peaked in early summer and mid-autumn but dropped during the typhoon season and winter. Yuan-Yang Lake is a net heterotrophic ecosystem (annual mean net ecosystem production −39.6 μmole O2 m−3). 3. Compared to the summer peaks, seasonal averages of GPP and R decreased by approximately 50% and 25%, respectively, during the typhoon season. Ecosystem respiration was more resistant to external disturbances than GPP and showed strong daily variation during typhoon seasons. 4. Changes in the quality and quantity of dissolved organic carbon controlled the temporal dynamics and metabolic regulation. External disturbances (typhoons) caused increased allochthony, increasing DOC and water colour and influencing lake metabolism. 5. Seasonal winter mixing and typhoon-induced water mixing in summer and autumn play a key role in determining the extent to which the lake is a seasonal carbon sink or source to the atmosphere. [ABSTRACT FROM AUTHOR]

This study documents offshore convective lines along the southeastern coast of Taiwan, a frequent but poorly understood mesoscale phenomenon that influences coastal weather during the Taiwan mei-yu season. Doppler radar and surface observations were gathered from a specially chosen period (11–15 May 1998) when the offshore convective lines were active off the southeastern coast of Taiwan. These observations were used to show the basic character, structure, and possible formative processes of offshore convective lines. The synoptic environment accompanying these events was found to be relatively undisturbed and featured uniformly prevailing southerly/south-southeasterly winds in the boundary layer with southwesterlies/westerlies aloft. Examination of radar data during the study period indicates that the lines generally occurred ∼10–30 km offshore and were characterized by an elongated narrow zone (∼5–10 km wide) of heavy precipitation. The lines were oriented roughly parallel to the coastline and generally did not move significantly. The intensity of the radar reflectivity associated with the lines exhibited a marked diurnal variation and was closely related to the coastal offshore flow developing at night. Detailed analyses of an event on 14–15 May 1998 further show the important physical link between the offshore flow and the development of the line. The offshore line was found to be located near and immediately ahead of the seaward extent of the offshore flow. Particularly, a very narrow zone (∼2 km) of low-level heavy precipitation (40–45 dBZ) coincided with regions of strong updrafts and convergence, where the prevailing southerly onshore flow encountered the cool offshore flow nearshore. This offshore flow–induced convergence, given a stable thermodynamic condition in the lowest ∼1 km in the inflow region, was a crucial low-level forcing that provided lifting to trigger moist deep convection in this case. The line’s precipitation tilt eastward was confined primarily to the warmer inflow side rather than feeding the offshore flow to the west of the line. No consistent upshear tilt of updrafts throughout the storm layer was observed, which is consistent with the presence of a strong westerly shear in the line’s environment. Both of these observations explain a relatively strong (weak) modification of low-level onshore (offshore) flow by precipitation. Additionally, a combination of surface and Doppler radar observations indicates that the leading edge of the offshore flow moved seaward very slowly at 0.7 m s-1 and possessed a frontal character with notable discontinuities in near-surface wind and temperature (instead of pressure and dewpoint temperature). [ABSTRACT FROM AUTHOR]

Twelve years (1985–96) of monthly house fire reports for 22 districts in Taiwan, a maritime subtropical island of east Asia, were analyzed to characterize its fire nature. The major effort focused on the identification of temporal variation signals and their possible links with meteorological variables. Two significant modes of house fires were identified: annual and diurnal. As revealed from the power spectral analyses of fire time series in every fire district, a pronounced annual cycle peak emerges, with a peak phase in December and a minimum phase in June. In contrast to the warm and dry summer fire season of three continental landmasses (i.e., the U.S. West, the Northwest Territories of Canada, and the large wildland of Australia), an active fire season appears during the cool, dry winter in Taiwan. The fires on this island are highly correlated with several hydrometeorological variables; a decrease (increase) in rainfall in the dry (wet) cool (warm) environment with strong (weak) winds facilitates (hinders) fire occurrence. Under the modulation of the annual variation, two distinct fire regimes are identified in the diurnal variation of fire occurrence over the entire year: midnight–early morning and late morning–night. A sharp increase in fire occurrence occurs in the midmorning after a phase of constant fire occurrence frequency in the first regime and a gradual reduction over the nighttime hours in the second regime. Although fire occurrence is significantly suppressed by rainfall during the warm wet summer, an inverse relationship between fire occurrence and relative humidity for both annual and diurnal variations in Taiwan suggests that relative humidity plays a crucial role in fire occurrence. [ABSTRACT FROM AUTHOR]

ABSTRACT Observations from the World Ocean Circulation Experiment PCM-1 moored current meter array in the East Taiwan Channel are analyzed and combined with TOPEX/Poseidon altimetry data and the Parallel Ocean Climate Model simulation to study Kuroshio variability and relationships to westward propagating sea surface height anomalies in the Philippine Sea. Approximately 60% of the total subinertial velocity and temperature variance in the Kuroshio east of Taiwan is associated with so-called "transport" and "meandering" modes revealed from empirical orthogonal function analysis. The transport mode is dominated by a 100-day peak, while the most coherent energetic meandering signals are found in three limited frequency bands centered near periods of 100 days, 40 days, and 18 days. The detailed structure of the meanders is studied by frequency domain EOF analysis, which also reveals a higher frequency meander centered near 10 days confined to the western side of the channel. On the 100-day timescale, the Kuroshio transport entering the East China Sea is strongly related to meandering of the Kuroshio, which in turn is caused by westward propagating anticyclonic eddies from the interior ocean. During low transport events, the Kuroshio meanders offshore and partly bypasses the East Taiwan Channel to flow northward along the eastern side of the... [ABSTRACT FROM AUTHOR]

This study analyzed the temporal/spatial distribution of the high‐temperature extremes (HTEs) in Taiwan. Three major weather types for HTEs were identified: the southerly/southwesterly (S/SW) (47.6%), western North Pacific subtropical high (SH) (35.9%), and tropical cyclone (16.5%). The S/SW type features anomalous warm advection in lower atmosphere and anomalous subsidence in all the altitudes around Taiwan. Different from the S/SW type, the SH type warms the surface primarily with increasing downward shortwave radiation. In June, the S/SW type was the most common. In July, both the S/SW and SH types dominated. In August, the tropical cyclone and SH types were more common. The subseasonal variation of extreme hot days (EHDs) for these three weather types is examined. Taipei and Dawu were two HTE hot spots in Taiwan. EHDs in Taipei occurred mostly in July and August, with the SH being the major type. Most EHDs in Dawu occurred in June, with the S/SW being the predominant type. These differences likely resulted from not only the subseasonal monsoon variation but also geographical differences. The interannual variability of the summer EHDs in Taiwan was found to be related to the phase and intensity of the El Niño‐southern oscillation events. The number of EHDs increased in the El Niño decaying summers and decreased in the La Niña decaying summers. The correlation between the number of summer EHDs and the Niño 3.4 SST anomaly reaches its peak in the previous winter (November/December). The associated mechanisms were discussed in the article. Key Points: Three major weather types associated with Taiwan's extreme hot days were identifiedTaipei and Dawu differed distinctly in the number of extreme hot days for all three major weather types and the timings of their occurrenceThe number of summer extreme hot days in Taiwan significantly increased (decreased) in the El Niño (La Niña) decaying years [ABSTRACT FROM AUTHOR]