Even a small rise in global average temperature has affected species across ecosystems, changing their genes, physiology, morphology, and phenology.
By Shreya Dasgupta
Responses to climate change scale from the smallest level of a gene to the largest level of an ecosystem. (Photo: amerune/Wikimedia Commons)
Global average temperatures have risen by about 1°C since 1880. But just one degree of human-induced warming has affected nearly all aspects of life on our planet, concludes a new study.
Climate change has affected species across ecosystems, changing their genes, physiology, morphology, and phenology, and affected their distributions, food webs, and overall interactions, researchers report in the new study published in the journal Science.
This finding was a total surprise, says lead author Brett Scheffers, an assistant professor in the department of wildlife, ecology, and conservation at the University of Florida. “We not only found ecological responses to climate change across freshwater, marine, and terrestrial ecosystems,” he says, “but these responses scaled from the smallest level of a gene to the largest level of an ecosystem.”
Numerous studies have attempted to tease out the impacts of climate change in the past. Scheffers collaborated with researchers from 10 countries to review previously published research, and compiled evidence of climate change responses across 94 ecological processes that are integral to healthy terrestrial, marine, and freshwater ecosystems.
Of the 94 ecological processes reviewed in the study, over 80 percent showed signs of response and distress, the researchers found.
“Some people didn’t expect this level of change for decades” study co-author James Watson, an associate professor at the University of Queensland in Australia and a scientist with the Wildlife Conservation Society, said in a statement. “The impacts of climate change are being felt with no ecosystem on Earth being spared.”
Many species — from salamanders to birds — are showing changes in their body size in response to climate change, for example. Some species are also producing smaller babies than before, the review notes. Animals have changed the timing of their migrations, temperate plants are flowering earlier in spring, many species have shifted their distributions, and some species have even altered their sex ratios as a consequence of warming temperatures.
These changes not only disrupt interactions between species, but affect people too, the study concludes.
Productivity in fisheries has decreased, for example, partly due to warming waters. Yields of important crops, such as rice, maize, and coffee, have declined in response to the effect of rising temperatures and increasing variability in rainfall over the last few decades. Warming temperatures have also triggered the spread of pests and increased the instances of disease outbreaks. Mosquitoes, too, are extending their distributions to areas that are now warmer than before, increasing the potential for spreading diseases such as chikungunya and dengue.
The extent of change is astonishing, Watson said, especially since the planet has experienced only a relatively small rise in temperature.
Disease-carrying mosquitoes are extending their distributions to areas that are now warmer than before, increasing the potential for spreading diseases such as chikungunya and dengue. (Photo: James Gathany/Public Domain)
To combat the negative effects of climate change, the study stresses recognizing the role of large, intact natural ecosystems. Healthy ecosystems are important not only because they act as repositories for carbon, but also because they can buffer and regulate local climate regimes, and allow species, including human populations, to respond and adapt to climate change, the authors write.
Policymakers and politicians must accept the affects of climate change, and take steps to curb greenhouse gas emissions, the researchers add.
“The science is undeniable that climate change is currently impacting and will continue to impact nature and society in ways that harm our health and well-being,” Scheffers says. “The responses we observed to just 1°C of warming should make everyone a little uncomfortable because if significant emissions cuts are not made in the very near future, experts predict that we might see 2°C to 3°C warming by the end of the century. This will be catastrophic for both the environment and people.”
This story originally appeared at the website of global conservation news service Mongabay.com. Get updates on their stories delivered to your inbox, or follow @Mongabay on Facebook, Instagram, or Twitter.