Thursday, December 20, 2007

Global Warming Could Affect Food Webs Across the World

Guest Post: Lucy Goodchild from Micropod Online and Society for General Microbiology

(TGW) - Levels of a climate cooling gas will change as carbon dioxide increases, affecting food webs along the way, said Dr Michael Steinke at a Society for General Microbiology press briefing today.

Microbes in the ocean produce the gas dimethyl sulphide, or DMS. It causes clouds to form above the sea, which reflect the sun’s rays away from the earth. Research suggests that plankton produce more DMS when they get hot so that clouds will cool them down. “Our work on the effect of carbon dioxide on DMS levels showed some interesting results” said Dr Steinke, from the University of Essex. “DMS production is likely to change in the future.”

DMS is responsible for the “seaside smell”. Dr Steinke discovered that plankton may use DMS when looking for prey like the way bees are attracted to fragrant flowers. “The role of DMS in climate change has been studied for years. Its role in marine ecology was unknown and this is what we are investigating.”

Marine animals including seals and birds use DMS to find food and navigate. “DMS plays an important role in oceanic food webs” said Dr Steinke. “If DMS levels change, many marine animals could find it more difficult to search for their prey.” This could have an effect on the food we eat.

Current discussions include using DMS in the “eco-engineering” of climate. Its cloud forming ability could be used to reduce global warming. However, Dr Steinke’s results show it may not be simple. “We have found that the production of DMS is much more complex than we thought and there will be plenty more surprises to come.”