A Numerical Study of Precipitation Characteristics over Taiwan Island during the Winter Season

C.-S. Chen; J.-M. Huang

doi:10.1007/s007030050032

Temporal Changes in Flow Regime along the River Vistula

Water ◽

10.3390/w13202840 ◽

2021 ◽

Vol 13 (20) ◽

pp. 2840

Author(s):

Ewa Bogdanowicz ◽

Emilia Karamuz ◽

Renata Julita Romanowicz

Keyword(s):

Flow Regime ◽

Winter Season ◽

Hydrological Regime ◽

Mean Value ◽

Social Perceptions ◽

Annual Data ◽

Spatial Changes ◽

Precipitation Characteristics ◽

Dry Spell ◽

Spell Length

The flow regime in the River Vistula is influenced by climatic and geographical factors and human intervention. In this study, we focus on an analysis of flow and precipitation variability over time and space following the course of the River Vistula. Multi-purpose statistical analyses of a number of runoff and precipitation characteristics were performed to present a general overview of the temporal and spatial changes. Since the important feature of the hydrological regime of Polish rivers is the seasonality of runoff associated with the occurrence of cold (winter) and warm (summer) seasons within a hydrological year, a seasonal approach is applied to describe specific seasonal features that can be masked when using annual data. In general, the results confirm popular impressions about changes in winter season runoff characteristics, i.e., significantly decreasing daily maxima, increasing daily minima and a decrease in concentration, and so a bigger uniformity of winter daily flows. An interesting behaviour of minimum flows in the summer has been revealed, which is contrary to social perceptions and the alarming changes taking place in the other parts of the world. Additionally, precipitation indexes related to the formation of droughts show no trends, e.g., the mean value of the maximum dry spell length.

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A Satellite Observational and Numerical Study of Precipitation Characteristics in Western North Atlantic Tropical Cyclones

Journal of Applied Meteorology ◽

10.1175/1520-0450(1994)033<0129:asoans>2.0.co;2 ◽

1994 ◽

Vol 33 (2) ◽

pp. 129-139 ◽

Cited By ~ 41

Author(s):

Edward B. Rodgers ◽

Simon W. Chang ◽

Harold F. Pierce

Keyword(s):

Tropical Cyclones ◽

North Atlantic ◽

Numerical Study ◽

Precipitation Characteristics

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Monsoonal Influence on Typhoon Morakot (2009). Part II: Numerical Study

Journal of the Atmospheric Sciences ◽

10.1175/2011jas3731.1 ◽

2011 ◽

Vol 68 (10) ◽

pp. 2222-2235 ◽

Cited By ~ 39

Author(s):

Jia Liang ◽

Liguang Wu ◽

Xuyang Ge ◽

Chun-Chieh Wu

Keyword(s):

Time Scale ◽

Numerical Experiments ◽

Numerical Study ◽

Wave Train ◽

Mainland China ◽

Low Frequency ◽

Typhoon Morakot ◽

Sensitivity Experiments ◽

Taiwan Island ◽

The Taiwan Strait

Abstract In the second part of this study, numerical experiments are conducted to investigate the influences of multi-time-scale monsoonal flows on the track change of Typhoon Morakot (2009). While the control simulation captures the slowing and northward deflections in the vicinity of Taiwan Island, the highly asymmetric rainfall structure, and the associated rainfall pattern, sensitivity experiments suggest that the westward movement prior to the landfall on Taiwan and the subsequent northward shifts in the vicinity of Taiwan were closely associated with the interaction between Morakot and multi-time-scale monsoonal flows. Prior to the landfall on Taiwan, Morakot moved westward directly toward Taiwan because of a synoptic wave train–like pattern, which consisted of Goni over mainland China, Morakot, and a cyclone over the western North Pacific with an anticyclone to the west of Morakot. Numerical simulation suggests that strong northerly winds between Morakot and the anticyclone reduced the northward steering component associated with the low-frequency flow prior to the landfall. Numerical experiments confirm that the northward track shifts that occurred in the vicinity of Taiwan Island were a result of the coalescences of Morakot with a quasi-biweekly oscillation (QBW)-scale gyre prior to the landfall on Taiwan and a Madden–Julian oscillation (MJO)-scale gyre in the Taiwan Strait. The simulation of Morakot and the associated sensitivity experiments agree with the previous barotropic study that the interaction between tropical cyclones and low-frequency monsoon gyres can cause sudden changes in tropical cyclone tracks.

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Investigation Of The Improvement Building Envelope Impact On Energy Consumption Using Energy Audit

MATEC Web of Conferences ◽

10.1051/matecconf/202030701031 ◽

2020 ◽

Vol 307 ◽

pp. 01031

Author(s):

Fatiha Mokhtari ◽

Djaffar Semmar ◽

Mourad Chikhi ◽

Nachida Kasbadji Merzouk ◽

Soumia Oukaci

Keyword(s):

Energy Consumption ◽

Numerical Study ◽

Winter Season ◽

Building Energy ◽

Building Envelope ◽

Energy Audit ◽

Effective Evaluation ◽

Heating And Cooling ◽

Space Cooling ◽

Reduction Of Energy Consumption

Effective evaluation on the thermal performance of building envelope plays an important role towards the reduction of energy consumption for space cooling and heating. In order to estimate the energy consumption for cooling, heating and the whole energy saving on the envelop designs; an improvements of thermal performances of this envelope are introduced. This trend is performed using a numerical study. The building is an office part of the Unit of Developmental for Solar Equipment (UDES) located at Bou-Ismail, an Algerian coastal city. Through the software PLEADES-COMFIE, building energy has been evaluated. The simulation results illustrate that; adding 90 mm thick insulation on the opaque walls and double glazing on windows produce a maximum saving of 50% and 10% annual energy required in heating and cooling. Also these proposed performances allow increasing indoor temperate of 4°C in winter season and decreasing.

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A Numerical Study on Impact of Taiwan Island Surface Heat Flux on Super Typhoon Haitang (2005)

Advances in Meteorology ◽

10.1155/2015/710348 ◽

2015 ◽

Vol 2015 ◽

pp. 1-11

Author(s):

Hongxiong Xu

Keyword(s):

Numerical Study ◽

Surface Heat ◽

Heat Fluxes ◽

Dominant Factor ◽

Surface Heat Fluxes ◽

Super Typhoon ◽

Typhoon Structure ◽

Taiwan Island ◽

Hurricane Wrf ◽

The Right

Three to four tropical cyclones (TCs) by average usually impact Taiwan every year. This study, using the Developmental Tested Center (DTC) version of the Hurricane WRF (HWRF) model, examines the effects of Taiwan’s island surface heat fluxes on typhoon structure, intensity, track, and its rainfall over the island. The numerical simulation successfully reproduced the structure and intensity of super Typhoon Haitang. The model, especially, reproduced the looped path and landfall at nearly the right position. Sensitive experiments indicated that Taiwan’s surface heat fluxes have significant influence on the super Typhoon Haitang. Compared to sensible heat (SH) fluxes, latent heat (LH) is the dominant factor affecting the intensity and rainfall, but they showed opposite effects on intensity and rainfall. LH (SH) flux of Taiwan Island intensified (weakened) Typhoon Haitang’s intensity and structure by transferring more energy from (to) surface. However, only LH played a major role in the looped path before the landfall of the Typhoon Haitang.

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