HC Deb 06 May 2004 vol 420 c1664W
Mr. Watson

To ask the Secretary of State for Environment, Food and Rural Affairs what evaluation she has made of experiments to use oceans to absorb more carbon dioxide by spraying them with iron filings and the impact this will have on global warming. [169239]

Mr. Morley

Experimental studies of iron fertilisation have so far been carried out on a relatively small scale, and computer models are needed to estimate the consequences of large scale fertilisation. Modelling studies of iron fertilisation are currently performed as part of Defra's Climate Prediction Programme at the Hadley Centre.

Iron fertilisation encourages extra growth of phytoplankton, which increases the uptake of carbon dioxide from the water and subsequently the atmosphere. Preliminary studies have indicated that even wide spread and continuous iron fertilisation would reduce levels of atmospheric carbon dioxide by only a small fraction, making it unlikely that there would be a significant impact on global warming. In addition, the consequences of such fertilisation on marine ecosystems could be severe.