Investigating Spatial and Temporal Dynamic of the Leeuwin Current using Time-series MODIS Data  


Authors / CoAuthors

Huang, Z.

Abstract

The Leeuwin Current has significant ecological impact on the coastal and marine ecosystem of south-western Australia. This study investigated the spatial and temporal dynamics of the Leeuwin Current using monthly MODIS SST dataset between July 2002 and December 2012. Topographic Position Index layers were derived from the SST data for the mapping of the spatial structure of the Leeuwin Current. The semi-automatic classification process involves segmentation, 'seeds' growing and manual editing. The mapping results enabled us to quantitatively examine the current's spatial and temporal dynamics in structure, strength, cross-shelf movement and chlorophyll a characteristic. It was found that the Leeuwin Current exhibits complex spatial structure, with a number of meanders, offshoots and eddies developed from the current core along its flowing path. The Leeuwin Current has a clear seasonal cycle. During austral winter, the current locates closer to the coast (near shelf break), becomes stronger in strength and has higher chlorophyll a concentrations. While, during austral summer, the current moves offshore, reduces its strength and chlorophyll a concentrations. The Leeuwin Current also has notable inter-annual variation due to ENSO events. In El Niño years the current is likely to reduce strength, move further inshore and increase its chlorophyll a concentrations. The opposite occurs during the La Niña years. In addition, this study also demonstrated that the Leeuwin Current has a significantly positive influence over the regional nutrient characteristics during the winter and autumn seasons.

Product Type

nonGeographicDataset

eCat Id

79209

Contact for the resource

  Custodian

EGD  

  Owner

Commonwealth of Australia (Geoscience Australia)  

  Custodian

Commonwealth of Australia (Geoscience Australia)  
Cnr Jerrabomberra Ave and Hindmarsh Dr GPO Box 378
Canberra
ACT
2601
Australia

Keywords

  • External PublicationAbstract
( Theme )
  • remote sensing
( Theme )
  • mapping
( Theme )
  • marine environmental baselines
( Theme )
  • marine
( Theme )
  • NERP
Australian and New Zealand Standard Research Classification (ANZSRC)
  • Marine Geoscience
  • Published_Internal

Publication Date

2014-01-01T00:00:00

Creation Date

Security Constraints

Australian Government Security ClassificationSystem    

Classification - unclassified

Legal Constraints

Creative Commons Attribution 4.0 International Licence    

Access - license

Use - license

Status

Purpose

Maintenance Information

notPlanned

Topic Category

oceans

Series Information

Lineage

The abstract was the result of NERP Marine Biodiversity Hub Project.

Parent Information

Extents

Reference System

Spatial Resolution

Service Information

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Source Information

NERP Marine Biodiversity Hub