Climatic Shifts – The Migration Of Climate Zones

rainforest 1

Climate change is forcing tropical tree species to move into cooler environments.

It is well known that climate change is affecting many different environments: the coral reefs are dying from acidification of the oceans, the sea ice is melting and temperatures are increasing across the world. However, a study published recently in the Proceedings of the National Academy of Sciences found that over the last decade, tropical forests in the Andes have been shrinking and changing directionally with time as a likely response to climate change.

“The effects of climate change are everywhere – you can’t escape it,” Kenneth J. Feeley, a researcher with Florida International University, said in a statement. “Some people hold the notion that the Amazon is an isolated ecosystem, immune to [temperature] disturbances. We need to change our mindset and open our eyes to the fact that even in the middle of the Amazon or the remote Andes Mountains, species are at risk. Tropical forests, and the thousands of rare or endemic species they support, are highly sensitive to changes in climate and that they are perhaps some of the most threatened ecosystems of all. Climate change is pervasive and dangerous.”

This is not an isolated incident either. The results of a study published in the journal Biological Conservation recently concluded that in Australia, the climate is warming to an extent that many specialised tree species that require cooler climates are struggling. Typically, these trees would start to shift to cooler environments, but as Craig Costion explained “they already live on mountain tops…they have no other place to go.”

Across the world, the phenomenon of “thermophilization,” is occurring. This is where the abundance of cold-tolerating highland species is decreasing while only heat-loving, lowland tree species are being left behind. As the cold-tolerating species retreat, more heat-tolerant species move in, resulting in a decrease in biodiversity and species richness. The results from numerous studies are indicating that the tropical species of tree are severely being affected by climate change and is pushing these species to the brink of extinction. There is a  knock-on effect of the shift in trees, “if tree species are dying back, then the animals that depend on them will inevitably dieback as well,” Feeley said.

It is not simply just the tropical trees that are being affected by climate change either. Boreal forests, which make up 30% of the planet’s forested area, are also shifting northwards in response to climate change. “Boreal forests have the potential to hit a tipping point this century,” International Institute for Applied Systems Analysis (IIAS) researcher Anatoly Shvidenko said in a statement. “It is urgent that we place more focus on climate mitigation and adaptation with respect to these forests, and also take a more integrated and balanced view of forests around the world.” In a study published in Science, it was concluded that boreal forest climate zones are moving northward at a rate ten times faster than the trees are able to migrate. Invasive species are becoming an occurrence in these areas as warmer and drier climates are established.

Boreal_big

Boreal forests are shifting northwards in response to climate change.

According to research in Nature Climate Changewith a warming of 2°C, about 5% of land would shift into a new climate zone. As the temperatures rise another 2°C, 10% of the land area shifts to a new zone.

Climate change has numerous effects, but maybe it is not yet fully understood how far reaching these effects are within the tropics, a largely unresearched area. The effects of climate change will be felt in every environment in the world, and to prepare for these changes to ecosystems and species, more research is required.

Advertisements

One response to “Climatic Shifts – The Migration Of Climate Zones

  1. Disappearing montane forests are akin to low-lying island chains that are being engulfed by rising seas. These species have nowhere to go, so they “drown” in the metaphorical sense and cease to exist. Very sad, and another among countless reasons to halt climate change as soon as possible!

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s