*** Welcome to piglix ***

Migration of Marine Species in the Northern Atlantic Ocean


The world's oceans are warming due to climate change. Climate change is caused by three major factors which are the greenhouse effect, variation in the sun's energy that reaches Earth, and changes in reflectivity within Earth's atmosphere and its surface. The greenhouse effect is caused by greenhouse gases that absorb sunlight. Energy from the sun that reaches Earth is either retained or sent into space. Greenhouse gases in Earth's atmosphere such as carbon dioxide, methane, and water vapor absorb energy which cause a blanketing effect that warms the earth. Aerosols such as black carbon also catalyze the warming effect as they are unreflective and absorb energy from the sun supplementing greenhouse gases in the warming effect.

These combined factors are warming the Earth's land as well as the oceans. Many fish species possess a certain range of water temperature that they are able to tolerate which is causing species to migrate to different areas where the water temperature is livable. The warming of the Atlantic Ocean is causing many fish species to shift north towards once cooler waters so they can live within their temperature range. Tropical species are being found outside their normal range and into more northern waters causing an array of ecological, economic, and fishery management problems.

William Cheung, a professor at the University of East Anglia, in the Sea Around Us Project at the University of British Columbia concluded that the oceans were warming at an average of 0.19 °C (32.34 °F) per decade and at 0.23 °C (32.41 °F) per decade in tropical waters. However, the north-east Atlantic has been warming at a rate of 0.49 °C (32.88 °F) per decade. Cheung and his colleagues were able to get these estimates by using the mean temperature of catch. They used data from 990 species within 52 marine ecosystems from 1970-2006. Using fisheries data and computer models, Cheung was able to estimate the shift of species. Species are migrating north at an average rate of 40 to 45 kilometers (25 to 28 mi) per decade. The study predicted that there will be a 60% shift of species towards northern waters within the next 41 years.


...
Wikipedia

...