Algal Bloom off Tasmania

  • Credit

    NASA image created by Jesse Allen, Earth Observatory, using data obtained from the NASA Goddard Earth Sciences DAAC.

MODIS images helped scientists detect a large algal bloom in the waters of the Tasmanian Sea south of Australia in late October. The SeaWiFS sensor confirms the presence of the bloom by showing high levels of chlorophyll along the east coast of Tasmania.

The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua and Terra satellites helped scientists identify this large algal bloom off the eastern coast of Tasmania. Large blooms have not been detected in the Tasman Sea in the past, and scientists from CSIRO Marine Research, the largest marine research organization in Australia, believe this one resulted from the natural upwelling of nutrients along the island’s coast. The bloom is made up of coccolithophores, and is not believed to be harmful to the coastal ecosystem.

MODIS imagery, such as the image above, revealed just how large this bloom is. The bloom forms bright blue-green clouds in the water that stretch from Flinders Island in the north down the entire east coast of Tasmania. The color is caused by light reflecting off the chalky outer scales of millions of microscopic coccoliths. The effect is a cloud of bright blue or green water in satellite imagery. In addition to helping scientists identify algal blooms, the MODIS images “provide a valuable interpretation for researchers wanting to understand any impact this species may have in the coastal or offshore environments,” said Dr Susan Blackburn, a CSIRO researcher, in a press release. The above MODIS image was acquired on October 20, 2004, by NASA’s Terra satellite.

Metadata

  • Sensor

    Terra/MODIS
  • Start Date

    2004-10-20
  • Event Start Date

    2004-10-18
  • NH Image ID

    12557
  • NH Event ID

    10523
  • NH Posting Date

    2004-10-28