If you were asked to show one photo that described what most of the world looked like it would be like the one below. The abyssal plain covers about 60% of the Earth’s surface. Found at depths below 2000 metres it is one of the least well known ecosystems on our planet.
Because it is so deep, so cold, and so isolated, scientists believed that climate change would not affect the abyssal plain. The latest research from a team led by Ken Smith of Monterey Bay Aquarium Research shows that this is not the case.
The abyssal plain goes through both short term and long term ecological changes not unlike other habitats. Based on 18 years of research they have found that life at their 4,000 and 5,000 metre deep sites was completely dependant on the life at the surface. As phytoplankton and other surface marine life die they become part of a slow ‘rain’ of food from above.
The deep sea "Dumbo" octopus
Changes in the surface waters can have huge effects on how much food falls to the bottom. As shallow water lie dies it sinks and may be eaten and re-eaten several times before it reaches the abyss. The trip from surface to seafloor could take months or even years. It is estimated that less than 5% of the surface food reaches the bottom.
Crinoids (related to starfish)
Studies show that small changes at the surface can affect available food at the bottom by a factor of ten. Scientists have been able to track the 1997-98 El Nino event that caused some abyssal animals to virtually disappear while others increased.
The incredible glass squid
According to Smith, "Essentially, deep-sea communities are coupled to surface production. Global change could alter the functioning of these ecosystems and the way carbon is cycled in the ocean."
The scientists suggest that the abyssal plain could best be studied using underwater robots and ocean floor automated instrument stations. The technology is there to establish a world wide abyssal monitoring program. If we don’t move quickly we wont have the base-line information needed to understand global warming in the deep sea.