The last time climate change impacted Earth's vegetation with notable intensity was about 21,000 years ago, in the aftermath of the last ice age. According to a new study, something similar is due to happen to our planet, and there's a chance the changes could manifest within the next 100 to 150 years and end up affecting Earth's ecosystems without exception.
In a study published Thursday in the journal Science, a multinational team of researchers studied fossil records and analyzed data from close to 600 websites to come up with a detailed analysis of how Earth's vegetation changed since the last ice age. According to the Weather Channel, this was done to predict how climate change could play a role as ecosystems transform due to the impact of global warming, as the scientists compiled what was described as the "most comprehensive" data on global ecosystems from the last ice age to the pre-industrial era.
Live Science broke down the methodologies used by the researchers in their analysis, which included classifying the changes they spotted into two categories. Compositional changes were defined as those that affected a specific location's plant species, while large structural changes were those that had a broader impact, such as deciduous forests becoming evergreen forests, or tundras becoming some type of forest. The researchers then classified the changes based on their level of impact, listing them down as "large," "moderate," or "low."
To further refine their analysis, the researchers then classified the different sites based on how global warming might have influenced the changes. As Live Science explained, this involved determining whether large changes, for instance, were brought about by human activity or the presence of live animals.Based on their findings, the researchers spotted a link between temperature and vegetation changes, observing that the areas where the temperature had changed the most were typically those where the vegetation had substantially shifted through the years. The impact was felt the greatest in the Northern Hemisphere's mid to high latitudes, and also in the southern part of South America, Australia, New Zealand, Oceania, the Indo-Pacific, and tropical and temperate parts of southern Africa.
Researcher Connor Nolan, a University of Arizona doctoral candidate and co-author on the new study, said in a press release on the school's website that the research revealed "big changes" in all parts of the world during the timeframe in question.
"About 70 percent of those sites experienced large changes in the species that were there and what the vegetation looked like."Speaking to AZCentral in a report published Saturday, study co-author Jonathan Overpeck, dean of the University of Michigan's School for Environment and Sustainability, said that Arizona could be the "canary in the mineshaft" and the perfect example of what could happen when climate change impacts our planet's vegetation. He explained that Arizona's gradual shift from woodlands to grassland to an area known for its deserts is "exactly the kind of structural change" that could happen in the future.
As cited by Live Science, Overpeck also warned that meeting the objectives set in 2015 during the Paris climate conference wouldn't be enough to reverse the large structural changes on a global scale, as only half of our planet's vegetation might be affected in a positive way. Furthermore, Overpeck said that failing to meet the above targets could result in "much wider" and more unpredictable changes across the planet.