Some curious creatures live in the deep sea, most of which are still unknown to us. A recent study shows that people have observed less than 0.001 percent of the global deep sea floor in the past 70 years. The area previously explored by dives corresponds to only about a tenth of the size of Belgium. It mainly includes areas that lie within 200 nautical miles around the United States, Japan and New Zealand. The rest of the sea floor has so far been hidden from our eyes. How would that be changed and why is the deep sea research important?
Climate change has a strong impact on the oceans. Global warming leads to higher temperatures and acidification on the surface of the sea and in flatter waters, which has significant effects on the organisms and ecosystems living there. The influence of climate change on the biodiversity of the deep sea is hardly known. Because the sea floor itself is largely a mystery to us. So far, studies on his topography are based primarily on calculations using satellites that collect mapping data from valleys and mountains on the sea floor. However, much more information can be obtained from direct observations and on-site pictures of the deep sea and their sea floor, especially in flat sections. But how many such exploration data are there?
Only a few areas on the seabed documented
Forschilders around Katherine Bell from Ocean Discovery League have now investigated how large the area of the sea floor explored so far. To do this, they compared 43,681 records of diving expeditions from 14 countries, which have been undertaken in 120 economic zones and on the high seas since 1958.
The evaluation showed that the data of the expeditions have so far covered a maximum of 0.001 percent of the sea floor at a depth of 200 meters. Accordingly, people have never seen the remaining 99.999 percent of the deep sea floor. This estimate already takes into account that some diving data is not public and therefore not included in the study. For comparison: if we had also explored only 0.0001 percent of the area from land (1489 square kilometers), we would only know about life on Earth about life in an area around as big as Texas. The area researched in the sea has so far measures at least 2130 and a maximum of 3823 square kilometers – this corresponds to about a tenth of Belgium.
The areas of the deep sea already visited include areas within a radius of 200 nautical miles around the United States, Japan and New Zealand, including Monterey Bay and Hawaii as well as the Suruga and Sagami Bay. So far, almost no diving explorations have been held in marine areas in other parts of the world. Especially since the 1980s, the dives have mainly focused on economic zones and flatter coastal areas instead of the High Lake, as the team found. In the 1960s, 51.2 percent of all diving activities still took place on today’s Hohen See; In the 2010s, this proportion fell to 14.9 percent. Most of the expeditions from researchers from the three countries mentioned as well as from France and Germany were carried out. These rich states therefore dominate costly deep -sea research. In addition, almost 30 percent of the pictures were taken before 1980, in black and white with low resolution.
Mammoth task marine research
“This small and distorted sample is problematic if you try to characterize, understand and manage a global ocean,” write Bell and her colleagues – also with a view to possible deep -sea mining to gain resources such as manganese. “We have to understand the ecosystems and processes of the deep sea much better in order to be able to make well -founded decisions about the management and maintenance of resources,” said Bell. But to collect more data is a mammoth task: The calculations of the team showed that it would take more than 100,000 years to measure and document the entire sea floor by divers, submarines or diving robots on site, even if 1,000 teams worldwide would examine three square kilometers every year.
“These estimates show that we have to fundamentally change the way we research and examine the global deep sea,” said Bell and her colleagues. They propose to carry out more diving expeditions with modern technology for data acquisition. In doing so, representative biogeographic locations should also be examined, which in total allow a statistical evaluation of the respective world region. In this way you could research the entire deep -sea floor without being anywhere. This would not only help mining, but also clarify the effect of the deep sea on the atmosphere, the climate and health of our planet and which organisms it offers a habitat. These could in turn deliver food, oxygen for breathing and possible new drug active ingredients, according to the team around Bell.
Source: Katherine Bell (Ocean Discovery League) et al.; Science Advances, Doi: 10.1126/sciadv.adp8602