Study notes threat of global warming

Temperatures and sea levels will rise, while heat waves are set to become more frequent and deadly

One possible explanation for the extinction of dinosaurs is that climate change disrupted the ecological balance and dinosaurs failed to adapt.

Scientific research has now suggested that the same situation could happen to humankind given the impacts of climate change on core ecological processes.

An international team of researchers studied the impact of global climate change that has occurred in the past few decades as a result of human activities, and found that a global increase in temperature of 1 degree Celsius has already had a significant affect on a wide range of basic biological processes, from genes to ecosystems.

"Global warming of 1 degree Celsius has had both a positive and negative impact on agriculture and food supply, because some crop species benefit from warmer conditions, but others are hampered," said Richard Corlett, director of the Center for Integrative Conservation at the Chinese Academy of Sciences' Xishuangbanna Tropical Botanical Garden.

"There have also been noticeable changes in marine fish catches, with commercially important species moving north as the oceans get warmer. Freshwater fish have also been affected, and the impact of global climate change has mostly been negative," Corlett said.

No ecosystem on Earth has been unaffected. For example, several commercial fish species have shrunk in the past 40 years, while some fruits, such as apples and peaches, which need cold winter temperatures, have also been affected.

In addition to reducing agricultural yields, rising temperatures have also affected people, as pest and disease outbreaks have increased.

The research results were published in the journal Science on Friday, describing the future of humankind as "unpredictable".

Political leaders across the world reached an agreement on the reduction of greenhouse emissions at the 2015 United Nations Climate Change Conference in Paris.

"The global commitments made at that meeting target a 2 degree Celsius rise in temperature, which is still dangerous," Corlett said.

"While the first 1 degree Celsius rise in temperature took a century, the next will only take a few decades, so both the human and animal kingdoms will have less time to adjust."

Another 1 degree Celsius rise would result in large decreases in some sensitive natural ecosystems, such as coral reefs, and the extinction of many species, while others will move to cooler areas.

"Climate change doesn't only affect temperatures. Changes in rainfall are more difficult to predict, but some places will get wetter and some drier. Sea levels will continue to rise and the oceans will become more acidic as they absorb carbon dioxide from the air. Heat waves will be more frequent and more deadly," Corlett said.

The research conclusion was reached after studying hundreds of previously published scientific papers. The scientists identified a set of core ecological processes and assessed the already observed impacts of climate change on each one.

"The research systematically evaluated the impact of climate change on different species on Earth. It aims to make people more aware of the urgent need for reductions of carbon emissions, and give decision-makers a better understanding of the impact of global warming," said Chen Jin, director of the botanical garden.

chengyingqi@chinadaily.com.cm