Even though the oceans warm up slower than land, a recently published study in the scientific journal, Science, shows that marine life has to move their ranges just as quickly as species on land to cope with the changing temperatures. This is the first time that the rate at which marine species have to change to cope with global warming has been quantified.
Animals and plants are optimally adapted to their surroundings. Therefore, when temperatures change due to global warming, plants and animals have to find ways of coping. One way to cope can be to relocate to areas with temperatures like those the species are used to. Another option is for the animals or plants to change the timing of seasonal events like hibernation, breeding, spawning or migration.
Animals and plants are optimally adapted to their surroundings. Therefore, when temperatures change due to global warming, plants and animals have to find ways of coping. One way to cope can be to relocate to areas with temperatures like those the species are used to. Another option is for the animals or plants to change the timing of seasonal events like hibernation, breeding, spawning or migration.
Spring temperatures arrived 5 to 10 days/decade earlier in the North Sea but by less in the Mediterranean and were delayed in the Black Sea.
Figure: Burrows et al. 2011.
“It is well-known that plants and animals can cope with global warming by relocating or changing when, for example, they hibernate or breed. But until now, nobody has looked at how fast these changes would occur”, says Senior Research Scientist Keith Brander from the National Institute of Aquatic Resources (DTU Aqua) in Denmark who is among the authors of a study recently published in the recognised scientific journal, Science.
In the study, 17 experts from around the world gathered information from global temperature records from the last 50 years as well as from over 300 scientific papers concerning how increasing temperatures affect animals and plants on land and in the sea. The results were surprising:
“Even though temperatures on land have increased faster than in the oceans, the rate at which species relocated or changed the timing of, for example, their breeding or hibernation was just as high in the oceans as it was on land,” says Keith Brander from DTU Aqua, who came up with the initial idea to look at how quickly species in the sea could be expected to change as a response to global warming.
Marine species have to move longer
The study shows that in order to keep up with the observed climate warming over the past 50 years, the world’s plants and animals would have moved around 2.5 km each year on average to track their optimal temperatures. But regional variations mean that in many areas marine species must respond much more rapidly to the changing climate than species on land.
“Because of the faster increase of temperatures on land, you might expect the species to change quicker on land that in the sea. This study shows that this is not true at all”, says Keith Brander and explains:
“On land, species can find different temperatures by moving a shorter way than species in the ocean. For example, by relocating to higher altitudes in mountains. In the oceans, temperatures are much more even. Here, if the temperature increases, the species would have to move a much larger distance to find the right temperature”.
Increased biodiversity in the North Sea
The average temperature in the Danish seas has increased by 1.5⁰C over the last 30 years and to track these changes, marine species have had to relocate.
“Some species in the Danish waters have had to move their ranges around 10 km each year during the last 50 years in order to cope with the changing water temperature,” says Keith Brander.
Surprisingly, the increasing water temperature and the species relocating have meant an increased number of animal and plant species in the North Sea:
“With regards to number of animal and plant species, the biodiversity in the North Sea has increased during the last 30 years due to global warming”, says Keith Brander, and explains that species adapted to live in warmer waters now find the Danish water temperatures suitable while some of the species adapted to live in colder waters are apparently able to adapt to the higher temperature. But not all fish species adapted to colder waters thrive in the warmer Danish waters.
“The numbers of the flatfish, the common sole, has been increasing in Danish waters. The sole is distributed all the way down to Africa, and thrives in the warmer Danish waters. In contrast, the European plaice is a flatfish species adapted to living in colder waters, and we see that the numbers of European plaice in Danish waters are going down compared to sole numbers. Yet, it is not a simple picture. For instance, a cold-water species, like the cod, is able to stay in Danish waters by adapting to changing temperatures by moving the time when they spawn,” says Keith Brander and continues:
“Today, Danish marine species are not threatened by global warming. But that can change. A hundred years from now, some Danish marine species might be in trouble”.
Contacts and sources:
Technical University of Denmark (DTU)
Citation: Michael T. Burrows, David S. Schoeman, Lauren B. Buckley, Pippa Moore, Elvira S. Poloczanska, Keith M. Brander et al 2011. The Pace of Shifting Climate in Marine and Terrestrial Ecosystems. Science, vol. 334, 652-655.
“It is well-known that plants and animals can cope with global warming by relocating or changing when, for example, they hibernate or breed. But until now, nobody has looked at how fast these changes would occur”, says Senior Research Scientist Keith Brander from the National Institute of Aquatic Resources (DTU Aqua) in Denmark who is among the authors of a study recently published in the recognised scientific journal, Science.
In the study, 17 experts from around the world gathered information from global temperature records from the last 50 years as well as from over 300 scientific papers concerning how increasing temperatures affect animals and plants on land and in the sea. The results were surprising:
“Even though temperatures on land have increased faster than in the oceans, the rate at which species relocated or changed the timing of, for example, their breeding or hibernation was just as high in the oceans as it was on land,” says Keith Brander from DTU Aqua, who came up with the initial idea to look at how quickly species in the sea could be expected to change as a response to global warming.
Marine species have to move longer
The study shows that in order to keep up with the observed climate warming over the past 50 years, the world’s plants and animals would have moved around 2.5 km each year on average to track their optimal temperatures. But regional variations mean that in many areas marine species must respond much more rapidly to the changing climate than species on land.
“Because of the faster increase of temperatures on land, you might expect the species to change quicker on land that in the sea. This study shows that this is not true at all”, says Keith Brander and explains:
“On land, species can find different temperatures by moving a shorter way than species in the ocean. For example, by relocating to higher altitudes in mountains. In the oceans, temperatures are much more even. Here, if the temperature increases, the species would have to move a much larger distance to find the right temperature”.
Increased biodiversity in the North Sea
The average temperature in the Danish seas has increased by 1.5⁰C over the last 30 years and to track these changes, marine species have had to relocate.
“Some species in the Danish waters have had to move their ranges around 10 km each year during the last 50 years in order to cope with the changing water temperature,” says Keith Brander.
Surprisingly, the increasing water temperature and the species relocating have meant an increased number of animal and plant species in the North Sea:
“With regards to number of animal and plant species, the biodiversity in the North Sea has increased during the last 30 years due to global warming”, says Keith Brander, and explains that species adapted to live in warmer waters now find the Danish water temperatures suitable while some of the species adapted to live in colder waters are apparently able to adapt to the higher temperature. But not all fish species adapted to colder waters thrive in the warmer Danish waters.
“The numbers of the flatfish, the common sole, has been increasing in Danish waters. The sole is distributed all the way down to Africa, and thrives in the warmer Danish waters. In contrast, the European plaice is a flatfish species adapted to living in colder waters, and we see that the numbers of European plaice in Danish waters are going down compared to sole numbers. Yet, it is not a simple picture. For instance, a cold-water species, like the cod, is able to stay in Danish waters by adapting to changing temperatures by moving the time when they spawn,” says Keith Brander and continues:
“Today, Danish marine species are not threatened by global warming. But that can change. A hundred years from now, some Danish marine species might be in trouble”.
Contacts and sources:
Technical University of Denmark (DTU)
Citation: Michael T. Burrows, David S. Schoeman, Lauren B. Buckley, Pippa Moore, Elvira S. Poloczanska, Keith M. Brander et al 2011. The Pace of Shifting Climate in Marine and Terrestrial Ecosystems. Science, vol. 334, 652-655.
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