The best of EcoWatch, right in your inbox. Sign up for our email newsletter!
Island Trees Have Nowhere to Run From Climate Change
By Marlene Cimons
Kyle Rosenblad was hiking a steep mountain on the island of Maui in the summer of 2015 when he noticed a ruggedly beautiful tree species scattered around the landscape. Curious, and wondering what they were, he took some photographs and showed them to a friend. They were Bermuda cedars, a species native to the island of Bermuda, first planted on Maui in the early 1900s.
"Sometimes, island species are transported by humans outside their native islands — either to a mainland continent or to another island — and manage to survive in the wild there, as the Bermuda cedar has done on Maui," said Rosenblad, a research associate with the Sax Lab at Brown University's department of ecology and evolutionary biology.
He had never been to Bermuda, but suspected its climate was different from Maui's. "Then it hit me: if my suspicion was correct, then this species, by succeeding in Maui's climate, was effectively showing us its biological buffer that might help it survive future climate change," Rosenblad said."However, we still didn't know whether this buffer would be wide enough to accommodate the changes in climate expected to occur on Bermuda."
In other words, the Bermuda cedar could cope with life on Maui, but that doesn't mean it could cope with life in Bermuda later this century.
A Bermuda beach
Existing research shows that island species are less diverse than their cousins on the mainland. That lack of diversity makes them vulnerable to changing conditions. On an island, for instance, every member of a particular tree species might be suited to cool weather, whereas on the mainland, some are suited to the cold, while others are built for the heat. If temperatures rise, at least some of the mainland trees, those built for warm weather, might endure, but the island trees could perish.
"If climate change makes a given island too warm for the species that live there — or too dry or too stormy — then those species will be stuck on their island with nowhere to escape," Rosenblad said.
Rosenblad and his colleagues — Dov Sax, head of the Sax Lab, and doctoral student Daniel Perret — investigated the dangers that climate change poses to island species by studying conifers, a group that includes cedars, firs and pines. "When unique island tree species are given a chance to grow outside their native islands, how much extra climate hardiness do they show?" Rosenblad said. "And will that extra hardiness be sufficient to help them survive predicted future changes in climate?"
Branches of a Bermuda cedar
What they found was troubling. Their work suggests that climate change could push many small island conifers — nearly a quarter of those they studied — into extinction by 2070. The smaller the island the more danger, as trees have nowhere to flee. The larger the island, the more varied the climate, meaning species can relocate to cooler areas. Their research appears in the journal Nature Climate Change.
"Our results took us by surprise," Rosenblad said. "We expect if these species are left to fend for themselves, climate change will eventually drive them extinct."
Species can adapt to new conditions, but climate change will make that difficult. "The rub is that for some species, the amount of hardiness and adaptability they have shown is still not enough to buffer them against the changes in climate that are expected to occur on their native islands," Rosenblad said.
Canary Island pine trees, one of the conifers used in the study
So, while the Bermuda cedar may thrive on Maui, adapting to the future climate of Bermuda "will require an even bigger stretch," he added. He added that while the Bermuda cedar is surviving in many different places, "sadly none of them has a climate that resembles the one that Bermuda is projected to have in 50 years." That being the case, he said, "we still don't have any evidence that it can handle the climatic changes that are expected to occur on its native island."
The scientists urged caution in interpreting the findings, as species might be hardier that the evidence suggests. "However, I still find our results highly concerning," Rosenblad said.
In conducting their study, the researchers relied upon data obtained from global digitized plant specimen collections. Focusing on 55 species of coniferous trees, they cross-referenced information about them with existing worldwide climate statistics to determine the climate conditions, such as temperature and precipitation, at each location where their study species were found, including their native islands and other sites. They then built computer models for each species which told the researchers how the species would fare under different combinations of climatic conditions, including climate conditions projected for their native islands in 50 years.
Norfolk Island pines, one of the conifers used in the study
Researchers said many island tree species likely will require "serious help" withstanding climate change. "Failing to provide this help could have dire consequences, not just for the tree species themselves," he said. Trees perform essential functions, he explained, "like helping to regulate the flows of water and nutrients through the ecosystem."
Researchers called for targeted conservation efforts to avert extinction. Moreover, many of these trees also are culturally significant to island residents, especially the Bermuda cedar.
"It remains an indelible Bermudian cultural symbol," Rosenblad said. "Its wood has long been prized by artisans and builders. There is even a Bermudian wedding tradition, in which the cake is presented carrying a cedar seedling on top, and the couple then plants the seedling together."
He added, " It's important to underscore the beauty of these trees — and help them avoid extinction — so future generations can benefit from all they have to offer."
Reposted with permission from our media associate Nexus Media.
EcoWatch Daily Newsletter
By Tracy L. Barnett
Sources reviewed this article for accuracy.
For Sicangu Lakota water protector Cheryl Angel, Standing Rock helped her define what she stands against: an economy rooted in extraction of resources and exploitation of people and planet. It wasn't until she'd had some distance that the vision of what she stands for came into focus.
Last week, the Peruvian Palm Oil Producers' Association (JUNPALMA) promised to enter into an agreement for sustainable and deforestation-free palm oil production. The promise was secured by the U.S. based National Wildlife Federation (NWF) in collaboration with the local government, growers and the independent conservation organization Sociedad Peruana de Ecodesarrollo.
The rallying cry to build it again and to build it better than before is inspiring after a natural disaster, but it may not be the best course of action, according to new research published in the journal Science.
"Faced with global warming, rising sea levels, and the climate-related extremes they intensify, the question is no longer whether some communities will retreat—moving people and assets out of harm's way—but why, where, when, and how they will retreat," the study begins.
The researchers suggest that it is time to rethink retreat, which is often seen as a last resort and a sign of weakness. Instead, it should be seen as the smart option and an opportunity to build new communities.
"We propose a reconceptualization of retreat as a suite of adaptation options that are both strategic and managed," the paper states. "Strategy integrates retreat into long-term development goals and identifies why retreat should occur and, in doing so, influences where and when."
The billions of dollars spent to rebuild the Jersey Shore and to create dunes to protect from future storms after Superstorm Sandy in 2012 may be a waste if sea level rise inundates the entire coastline.
"There's a definite rhetoric of, 'We're going to build it back better. We're going to win. We're going to beat this. Something technological is going to come and it's going to save us,'" said A.R. Siders, an assistant professor with the disaster research center at the University of Delaware and lead author of the paper, to the New York Times. "It's like, let's step back and think for a minute. You're in a fight with the ocean. You're fighting to hold the ocean in place. Maybe that's not the battle we want to pick."
Rethinking retreat could make it a strategic, efficient, and equitable way to adapt to the climate crisis, the study says.
Dr. Siders pointed out that it has happened before. She noted that in the 1970s, the small town of Soldiers Grove, Wisconsin moved itself out of the flood plain after one too many floods. The community found and reoriented the business district to take advantage of highway traffic and powered it entirely with solar energy, as the New York Times reported.
That's an important lesson now that rising sea levels pose a catastrophic risk around the world. Nearly 75 percent of the world's cities are along shorelines. In the U.S. alone coastline communities make up nearly 40 percent of the population— more than 123 million people, which is why Siders and her research team are so forthright about the urgency and the complexities of their findings, according to Harvard Magazine.
Some of those complexities include, coordinating moves across city, state or even international lines; cultural and social considerations like the importance of burial grounds or ancestral lands; reparations for losses or damage to historic practices; long-term social and psychological consequences; financial incentives that often contradict environmental imperatives; and the critical importance of managing retreat in a way that protects vulnerable and poor populations and that doesn't exacerbate past injustices, as Harvard Magazine reported.
If communities could practice strategic retreats, the study says, doing so would not only reduce the need for people to choose among bad options, but also improve their circumstances.
"It's a lot to think about," said Siders to Harvard Magazine. "And there are going to be hard choices. It will hurt—I mean, we have to get from here to some new future state, and that transition is going to be hard.…But the longer we put off making these decisions, the worse it will get, and the harder the decisions will become."
To help the transition, the paper recommends improved access to climate-hazard maps so communities can make informed choices about risk. And, the maps need to be improved and updated regularly, the paper said as the New York Times reported.
"It's not that everywhere should retreat," said Dr. Siders to the New York Times. "It's that retreat should be an option. It should be a real viable option on the table that some places will need to use."
Leaked documents show that Jair Bolsonaro's government intends to use the Brazilian president's hate speech to isolate minorities living in the Amazon region. The PowerPoint slides, which democraciaAbierta has seen, also reveal plans to implement predatory projects that could have a devastating environmental impact.