A recent breakthrough study co-authored by a Swedish researcher engaged in Future Earth, Deliang Chen, found a high degree of interconnectivity between climate vulnerable regions known as tipping elements. Scientists identified long-distance linkages in climate variability between the Amazon rainforest and Tibetan plateau, showing how changes in one area can trigger changes in another halfway across the globe.  

Tipping elements are components of the Earth system susceptible to tipping points, which are critical thresholds that can cause significant and irreversible changes when exceeded. The interconnectivity of tipping elements and how they can influence one another is not well understood by scientists. It is really only during the last few years that possible linkages among tipping elements have been discussed.

Connecting the dots

To help fill this knowledge gap, Teng Liu and colleagues from China, Europe and Israel applied the theory of complex networks to investigate potential teleconnections (climate variability links over long distances) between tipping elements. The study, in the January edition of Nature Climate Change, focuses on the Amazon Rainforest Area (ARA), home to the world’s largest tropical rainforest and a quarter of the world’s species. 

The ARA is an area of particular concern; the Intergovernmental Panel on Climate Change reports the area’s high deforestation rates combined with a warming planet could be nearing a tipping point. The Amazon has been losing resilience since the early 2000s and forest dieback could rapidly transform this lush rainforest into savanna. 

“The Amazon has been identified as probably the most important tipping element because of its size and its importance to the Earth’s climate system, both in terms of the carbon cycle and water cycle,” said Chen speaking to Future Earth.

The researchers analyzed air temperature changes in 65,000 subregions over the past four decades. The study found strong teleconnections  between the ARA and regions such as the Tibetan Plateau (TP) and West Antarctic ice sheet. 

The study hones in on the connection between the ARA and TP, which supplies a significant portion of water for nearly two billion people and is warming at a far quicker rate than the global average. Liu and colleagues identified a 20,000 kilometer propagation pathway connecting South America to the Tibetan Plateau via Southern Africa and the Middle East.

“Logging, road construction and warming are already today stressing the Amazon rainforest, and will likely do so even more in the future – and while the Amazon region is of course an important Earth system element by itself, it’s also a burning question if and how changes in that region could affect other parts of the world,” said Jingfang Fan from Beijing Normal University, China, and the Potsdam Institute for Climate Impact Research in Germany. 

“For the first time we’ve now been able to robustly identify and quantify these so-called teleconnections. Our research confirms that Earth system tipping elements are indeed inter-linked even over long distances, and the Amazon is one key example of how this could play out.”

The connection between the TP and Amazon shows a negative correlation for precipitation-related indicators and a positive correlation for temperature-related indicators. The researchers also found the TP snow cover extent has been losing stability and approaching a tipping point since 2008.

Liu and colleagues showed why tipping elements should not be viewed in isolation and the potential for tipping cascades. The study’s findings highlight the need for immediate and robust action to mitigate greenhouse gas emissions and prevent tipping elements from crossing their critical thresholds.  

“We should not be looking at key hotspots like the Amazon in isolation,” said Chen when asked of the policy implications for his research. “What is happening locally is not only caused by local factors. The nature of the climate system has no national or regional border. We need to employ systems thinking on a global scale.”