|Author's Email Address
||This thesis had been viewed 5340 times. Download 286 times.|
||Marine Environment and Engineering|
|Type of Document
||Seasonal variation of SPM concentration in the Taiwan Strait using satellite data|
|Date of Defense
Suspended particulate matters
Moderate Resolution Imaging Spectroradiometer
||The Taiwan Strait is located in the part of the Western Pacific, and is an important trade route in history. The interaction between wind and wave is causing a series of changes in the Taiwan Strait. Also the climate change caused the record-breaking precipitation, landslide and seabed erosion or deposition.|
Surface SPM concentration data from MODIS satellite together with wind, wave and current data from operational results have been used to assess the seasonal variations in SPM dynamics in Taiwan Strait. The Strait is characterized by strong tidal currents and a distinct seasonal pattern in wind climate. During summer monsoon winds are generally blowing from the south and warm water with low SPM concentration is entering the Strait from the South China Sea. Higher SPM concentrations are found along the coasts and in the shallow areas of the Strait. These higher turbidity areas are caused by local resuspension and by high river runoff. Indeed, mountain rivers from Taiwan may carry huge amount of sediments into the Strait during short periods of heavy rains associated with typhoons during the summer season. These sediments are, however, rapidly dispersed in the sea and result in a relatively small increase in the surface SPM concentration during a limited period of time. Surface SPM concentrations in winter are higher than in summer. During winter monsoon winds are generally blowing from the NE and the China coastal current flows towards the SW. The higher SPM concentrations in winter are caused by higher wave induced resuspensions, but also by the larger import of SPM from the Chinese coastal current into the Strait.
Especially, there are the extreme events in summer, such as typhoon. The heavy rainfall caused by typhoon induced the river discharge increasing. The terrigenous sediment following the river discharge flowed into the Taiwan Strait and gathered at Tanshui and Zhaoshui river estuary. The maximum of precipitation and river discharge happened in typhoon period and SPM concentration peak happened after typhoon period. Consequently, after typhoon one month, the sediment caused by typhoon would dispersal. It represented the extreme event will not effect the SPM averaged distribution.
||Hao-Cheng Yu - chair|
Michael Fettweis - co-chair
Jason C.S. Yu - advisor
Indicate in-campus at 0 year and off-campus access at 2 year.|
|Date of Submission