Losing Penguins Due to Climate Change
Adélie penguins, one of two true Antarctic penguins (other being the Emperor penguin), have survived in Antarctica for nearly 45,000 years. They inhabit all over the continent, nesting on land during the summer and migrating during the winter for food. During the thousands of years, they have always adapted to past glacial expansions and sea ice fluctuations.
However, a new study suggests that the current climate change and global warming may pose an existential threat to their colonies on the Antarctic continent. Led by oceanographer Megan Cimino from University of Delaware, the research found that up to 60% of current Adélie penguin habitat could be unfit to host colonies by the end of the 21st century.
While the annual warming is necessary for the penguins to gather on their rocky breeding grounds, longer warm periods shrink the icy habitat for the following winter.
“It is only in recent decades that we know population declines are associated with warming, which suggests that many regions of Antarctica have warmed too much and that further warming is no longer positive for the species,” Cimino said.
A similar study in 2009 concluded that the Emperor penguin could also be facing extinction by 2100 as the sea ice continues to melt.
The researchers used data on expected levels of warming over this century as predicted by the Intergovernmental Panel on Climate Change of the United Nations. And along with a combination of field survey data and high-resolution satellite imagery from 1981 to 2010, the scientists were able to identify population trends at each colony site. Statistical models were then created to derive a relationship between the trends and the climate, represented by sea surface temperature and sea ice concentration. Finally, the relationship was incorporated into future climate projections to estimate the quality of penguin habitats.
They found diverging trends at different sites, reporting that climate change impacts will be highly site-specific, based on regional climate trends. Some colonies, like the population near Palmer Station, a United States research hub in northern Antarctica, declined by over 80%. Other cities were stable or even growing.
Many Antarctic researchers believe that climate change will affect penguins in two ways: the quality and availability of both food and nesting habitats.
Warming seas could reduce the current abundance of penguins’ prey, resulting in changes in the birds’ diet.
“Changes in [sea] ice and temperature can cause changes in the food, krill and fish.” In some areas, Cimino comments, “the fish populations have gone down a ton, so their major diet in those areas is krill. In other areas, these penguins eat more fish, which are a more nutritious food source.”
As for nesting habitats, the warming could yield unprecedented rain or prematurely melt snowfall, creating puddles on the ground.
According to Cimino, this is a danger to the eggs and chicks born during breeding season. “For penguins who lay their eggs on the ground … rain and puddles are bad because eggs can’t survive when they’re lying in a pool of water. Chicks that don’t have waterproof feathers can become wet and die from hypothermia.”
However, David Ainley, a senior biologist of HT Harvey & Associates, emphasized that the loss of sea ice may ultimately be a greater threat than warming sea temperatures.
“The Adélie penguin is a sea ice obligate and only occurs where there is sea ice for a good part of the year…Where sea ice is disappearing in the northern Antarctic peninsula, the Adélie penguin is disappearing.”
While the study’s projections look grim for the penguins, Cimino and her colleagues did identify several refugia where the penguins could survive. These locations will allow the birds to survive periods of adverse climate. Safe havens include the Ross Sea and Amundsen Sea, two bodies of water in the Southern Ocean where the Adélie penguin colonies can migrate south.
On the otherwise desolate continent, seven nations have territorial claims while 30 countries operate research stations. Given the disjointed nature of Antarctic politics, consistent resource management can be difficult to achieve. Still, Cimino believes it is imperative to prioritize conservation, like establishing marine protected areas and placing fishing restrictions, in havens that could shelter the Adélie penguins from climate change.
Light Pollution Brings Early Springs
Ever since widespread use of electricity was adopted by cities, light pollution became an issue with effects no one really understood in the early 20th century. Light pollution occurs when streetlights and other artificial light sources brighten up the night sky, disrupting ecosystems and obscuring stars. In fact, 99% of people living in the United States and Europe can no longer see the Milky Way.
Despite these effects, very little research has been conducted on this topic compared to issues like climate change. Out of the handful, majority focused on its impact on behavior. But, a recent research, the first to study the effect of light pollution on plant dynamics, seems to suggest that it might be causing spring to come earlier.
Published in the Proceedings of the Royal Society B, scientists, including Richard Ffrench-Constant, charted the relationship between light pollution and the timing when trees produce buds. The results showed that trees, like the European ash, sycamore, beech, and pedunculate oak, in brighter areas tended to bud earlier compared to those in darker areas. The study also notes that smaller plants growing directly under streetlights could more heavily affected.
Researchers used data collected by citizen scientists along with data quantifying artificial light recorded by the Defense Meteorological Satellite Program’s Operational Linescan System from 1999 through 2011. The team also included air temperature data in the United Kingdom.
It is important to note that the correlative, not causative.
Other scientists have also given their opinion on how light pollution alters plant cycles, reflecting what the new study suggested. Eric Vandernoot, the lab coordinator of the Florida Atlantic University Astronomical Observatory, commented that the light pollution “threw their bud dormancy out of whack, along with their growth patterns and time when they drop their leaves and fruit”. Thomas Rötzer, a professor at Technical University Munich, says that trees might grow in the direction artificial light is shining on them.
And if trees are budding earlier, this could have a larger effect on the surrounding ecosystem for insects and birds whose life cycles sync with the trees. An example, cites Cheryl Ann Bishop, communications director of the International Dark-Sky Association, is when moths fly toward porch lights. When moths are attracted to the light, their predators follow. Because the moths are quickly eaten, they can’t serve their other natural purposes in that system.
“The bottom line is that the ecosystem is being disrupted,” Bishop concludes. “It’s not the natural order of things.”
Light pollution also produces heat, which makes studying the relationship between rising temperatures and earlier budburts tricky.
“You can’t really separate out factors that work on synergy, and most environmental effects are synergistic,” mentions Kerissa Battle, president and CEO of the nonprofit Community Greenways Collaborative, which works to restore ecosystems. “But statistically, you can isolate factors.”
The study’s authors emphasized the need for further research into the impacts of differing wavelengths of light. Ffrench-Constant, in particular, also stressed that the results “highlight the need to carry out experimental investigation into the impact of artificial night-time lighting on phenology and species interactions.”
Woodland Trust citizen science manager, Dr. Kate Lewthwaite, gave a statement: “As the seasons become less and less predictable, our native wildlife may struggle to keep up with fluctuations that affect habitats and food sources. Hopefully this research will lead to new thinking on how to tackle such issues, and will help influence future development decisions.”
Recommended Reading: All the Light We Cannot See by Anthony Doerr
Signs Show that Ozone Hole is Finally Healing
After three decades of observation, a research team, led by Susan Solomon, professor of atmospheric chemistry and climate science at MIT, has finally found the first fingerprints of healing in the Southern Hemisphere ozone hole.
Two chemists at the University of California, Irvine named Mario Molina and Sherwood Rowland published in 1974 detailing the threats to the ozone layer from chlorofluorocarbon (CFC) gases. At the time, CFCs were commonly used in spray bottles and refrigerator coolants, rapidly accumulating in the atmosphere. Their groundbreaking research, for which the two were awarded the 1995 Nobel Prize in chemistry, concluded that the atmosphere only had a “finite capacity for absorbing chlorine” atoms in the stratosphere.
The two were widely attacked by the chemical industry, vindicated only 11 years later, in 1985, when a team of English scientists discovered a hole in the ozone layer due to the CFCs in the atmosphere. Implications meant that the loss of the protective ozone could lead to increased rates of skin cancer among other effects.
Ever since the discovery, scientists and researchers have remained heavily concerned, compiling data to study its causes and effects. The research led to the implementation of the 1987 Montreal Protocol, which quickly phased out industrial CFCs, stabilizing the ozone layer.
The ozone hole forms annually over Antarctica, beginning in August and peaking in October. While the hole itself has stabilized itself over time, the size varies from year to year, influenced by changes in meteorology and volcanism, making it difficult to identify a healing trend. Solomon’s team compared September ozone measurements, collected from balloon data and satellites, with statistical simulations that predict ozone.
October 2015 ozone hole was the largest on record, which Solomon attributes largely to the April eruption of the Calbuco volcano in Chile. Though volcanoes themselves do not spew chlorine molecules into the atmosphere, their contribution of small particles increases the number of polar stratospheric clouds that react with human-made chlorine.
“When volcanoes team up with man-made chlorine, it’s a toxic mix and Antarctica is particularly vulnerable,” said study co-author Susan Solomon, of the Massachusetts Institute of Technology.
“But when we looked at the September data, we saw it was getting smaller. It was pretty cool to see it closing. The chemicals will slowly decay over time.”
The researchers’ analysis showed that the 12 million km2 hole reach its peak until later in the southern spring, indicating that the September hole is shrinking. In fact, the study reports that the ozone hole has shrunk by more than 4 million km2 and is not as deep as it used to be.
“The fact that the ozone hole is opening later is really the key here,” comments Solomon. “It is opening later, it is smaller, and its depth is depleted. All of the measurements are independent, and when they all point to this [healing], it is hard to imagine any other explanation.”
The reduction has matched previous model predictions and that more than half of the shrinkage could be traced to the reduction in atmospheric chlorine. These findings suggest that ozone healing is right on pace with the expected timeline.
Donald Blake, a colleague at University of California, Irvine, praises the research, considering it to be the most complete study of polar ozone to date.
Despite the good news, a full recovery is not expected until 2050 or 2016. The production of CFC ceased in the 1990s, but have lifetimes of fifty to hundred years, so the chlorine molecules produced in the 1970s and ‘80s are still present.
Still, “It’s been quite a remarkable history,” explains Solomon. “It gives us hope that we shouldn’t be afraid to tackle large environmental problems. It was amazing to see how quickly innovation solved the problem with CFCs so we got rid of them yet still have hair spray and air conditioning. We’re starting to see the same thing with global warming. We should look at the ozone problem and realize that nations can get together and come up with solutions.”