Category Archives: Environment

DroughtWatch: Another week, still no change


The latest graphic report on California’s seemingly endless dry spell from the United States Drought Monitor:

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Soil takes in far less CO2 than previously thought


More grim climate change news, this time from the University of California, Irvine:

By adding highly accurate radiocarbon dating of soil to standard Earth system models, environmental scientists from the University of California, Irvine and other institutions have learned a dirty little secret: The ground will absorb far less atmospheric carbon dioxide this century than previously thought.

Researchers used carbon-14 data from 157 sample sites around the world to determine that current soil carbon is about 3,100 years old – rather than the 450 years stipulated by many Earth system models.

“This work indicates that soils have a weaker capacity to soak up carbon than we have been assuming over the past few decades,” said UCI Chancellor’s Professor of Earth system science James Randerson, senior author of a new study on the subject to be published Friday in the journal Science [$30 to read]. “It means we have to be even more proactive in finding ways to cut emissions of fossil fuels to limit the magnitude and impacts of climate warming.”

Through photosynthesis, plants absorb CO2 from the air. When trees and vegetation die and decay, they become part of the soil, effectively locking carbon on or beneath the Earth’s surface – keeping it out of the atmosphere, where it contributes to global warming. In their study, the researchers showed that since this process unfolds over millennia versus decades or centuries, we should expect less of this land carbon sequestration in the 21st century than suggested by current Earth system models.

“A substantial amount of the greenhouse gas that we thought was being taken up and stored in the soil is actually going to stay in the atmosphere,” said study co-author Steven Allison, UCI associate professor of ecology & evolutionary biology and Earth system science.

In recent years, scientists have used highly complex, computer-based Earth system models – compilations of code integrating data on the planet’s oceans, land surfaces, ice masses, atmosphere and biological systems – to draw conclusions about potential future changes in regional and global temperatures, drought, sea levels and other phenomena.

The models don’t explicitly provide the age of carbon in soils, but lead author Yujie He, a UCI postdoctoral scholar when the study was conducted, said that she and her colleagues figured out a way to improve them through simplification and the addition of dating methods well-established in the scientific community.

“Radiocarbon is an excellent tool for understanding soil dynamics,” He said. “Our study demonstrated that by working to reduce the complexity of Earth system models and combining observational data, we could get them to reveal surprising findings.”

The authors said that adding more carbon to that which has been in the ground for thousands of years is problematic given the pace at which the Earth seems capable of integrating it.

“If we waited 300, 400, 1,000 years, then that carbon – we think – would go into the soil. But that’s not going to help us in dealing with climate change, which is happening now,” Allison said. “You have to do a lot of risk assessment to say, well, what’s the actual cost of just waiting for that sequestration, and what policies should we implement to avoid that possible cost? That’s outside the realm of our actual work here, but what we can say is that the problems of carbon emission and climate change are worse than what we expected previously.”

Also contributing to the study were Susan Trumbore of the Max Planck Institute for Biogeochemistry, Margaret Torn and Lydia Vaughn of the Lawrence Berkeley National Laboratory, and Jennifer Harden of Stanford University and the U.S. Geological Survey.

Rising oceanic CO2 levels damage brains of fish


The latest research on the consequences of the gunger for fossil fuels, via the University of Miami Rosenstiel School of Marine and Atmospheric Science:

In a first-of-its-kind study, researchers from the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science and the ARC Centre of Excellence for Coral Reef Studies at James Cook University showed that increased carbon dioxide concentrations alters brain chemistry that may lead to neurological impairment in some fish.

Understanding the impacts of increased carbon dioxide levels in the ocean, which causes the ocean to become more acidic, allows scientists to better predict how fish will be impacted by future ocean acidification conditions.

“Coral reef fish, which play a vital role in coral reef ecosystems, are already under threat from multiple human and natural stressors,” said lead author of the study Rachael Heuer, a UM Rosenstiel School alumna which conducted the study as part of her Ph.D. work. “By specifically understanding how brain and blood chemistry are linked to behavioral disruptions during CO2 exposure, we can better understand not only ‘what’ may happen during future ocean acidification scenarios, but ‘why’ it happens.”

In this study, the researchers designed and conducted a novel experiment to directly measure behavioral impairment and brain chemistry of the Spiny damselfish, (Acanthochromis polyacanthus) a fish commonly found on coral reefs in the western Pacific Ocean.

During a three-week period, the scientists collected spiny damselfish from reefs off Lizard Island located on Australia’s Great Barrier Reef. The fish were separated into two groups–those exposed to ordinary CO2 “control” conditions and those exposed to elevated CO2 levels that are predicted to occur in the near future, but have already been observed in many coastal and upwelling areas throughout the world. Following the exposure, the fish were subjected to a behavioral test, and brain and blood chemistry were measured.

The unique behavioral test, employed a two-choice flume system, where fish were given the choice between control seawater or water containing a chemical alarm cue, which they typically avoid since it represents the smell associated with an injured fish of its own species.

The researchers found that the damselfish exposed to elevated carbon dioxide levels were spending significantly more time near the chemical alarm cue than the control fish, a behavior that would be considered abnormal. The measurements of brain and blood chemistry provided further evidence that elevated CO2 caused the altered behavior of the fish.

“For the first time, physiological measurements showing altered chemistry in brain and blood have been directly linked to altered behavior in a coral reef fish,” said UM Rosenstiel School Maytag Professor of Ichthyology and lead of the RECOVER Project Martin Grosell, the senior author of the study. “Our findings support the idea that fish effectively prevent acidification of internal body fluids and tissues, but that these adjustments lead to downstream effects including impairment of neurological function.”

“If coral reef fish do not acclimate or adapt as oceans continue to acidify, many will likely experience impaired behavior that could ultimately lead to increased predation risk and to negative impacts on population structure and ecosystem function,” said Heuer, currently a postdoctoral researcher at the University of North Texas. “This research supports the growing number of studies indicating that carbon dioxide can drastically alter fish behavior, with the added benefit of providing accurate measurements to support existing hypotheses on why these impairments are occurring.”

The study, titled Altered brain ion gradients following compensation for elevated CO2 are linked to behavioural alternations in a coral reef fish,  [open access]was published in the Sept. 13 online issue of the journal Scientific Reports. The study’s co-authors include: Rachael Heuer; Martin Grosell; Megan J. Welch and Jodie L. Rummer and Philip L. Munday from the ARC Centre of Excellence for Coral Reef Studies at James Cook University.

The National Science Foundation, a University of Miami Koczy Fellowship, and the ARC Centre of Excellence provided funding support for the study. Heuer was also funded by an NSF Graduate Research Fellowship to conduct the research.

Map of the day: Health of the planet’s vegetation


From the government’s National Integrated Global Drought Information System, with red being worst and blue best:

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Plastics prove pervasive in Great Lakes tributaries


The types of plastics pervasive in streams leading to the Great Lakes, via the USGS microplastics website.

The types of plastics pervasive in streams leading to the Great Lakes, via the USGS microplastics website.

As longtime readers know, one of our ongoing concerns here has been the growing body of evidence that plastics, still relatively new when esnl
was a child, are now being linked to a growing number of environmental woes and health problems.

And as with DDTvinyl chloride, asbestos, and a host of other compounds, we are only learning about the risks years after the substances have invaded our lives and environments.

Now comes word that plastics, present everywhere in our homes, workplaces, and oceans, have invaded the waters leading into Great Lakes.

From the U.S. Geological Survey:

Microplastics fall off decomposing bottles and bags, wear off of synthetic clothing and are manufactured into some toothpastes and lotions. Scientists with the U.S. Geological Survey and State University of New York at Fredonia studied 107 water samples collected from 29 Great Lakes tributaries in Minnesota, Wisconsin, Indiana, Michigan, Ohio and New York, and found microplastics in all samples. Together, these 29 tributaries account for approximately 22 percent of the total river water that flows into the Great Lakes.

“These microplastics, which are harmful to animal and possibly human health, will continue to accumulate in the Great Lakes well into the future,” said Austin Baldwin, a USGS scientist and the lead author of the report. “Our findings can help water managers better understand the types and sources of microplastics in rivers, and which rivers are the most polluted with microplastics.”

Baldwin noted that the study underestimates the actual microplastic concentrations in the rivers because the scientists sampled large microplastics greater than 0.33 millimeters (mm). The majority of microplastics are smaller than 0.1 mm.

Key findings from the study include:

  • The highest concentration of microplastics was detected in the Huron River at Ann Arbor, Michigan, at 32 particles per cubic meter, or p/m3;
  • High levels of microplastics were also detected in the Buffalo River at Buffalo, New York (31 p/m3), the Ashtabula River near Ashtabula, Ohio (23 p/m3), and the Clinton River near Mt. Clemens, Michigan (21 p/m3);
  • The median concentration of microplastics in all samples was 1.9 p/m3;
  • Urban watersheds had the highest concentrations of microplastics; and
  • Microplastics were also present in streams in forested and agricultural areas.

The scientists found various forms of microplastics in the river samples: fibers, fragments, films, foams, and pellets or beads. Plastic fibers, which come from items such as synthetic clothes, diapers and cigarette butts, were the most common type detected, at 71 percent of the total particles. The least common form found in the river water was microbeads, which are the only form banned by the United States Congress. This ban has not yet taken effect.

“We were surprised by the small amount of plastic beads and high amount of fibers found in the samples,” Baldwin said. “These unexpected findings demonstrate how studies like ours are critical to better understanding the many forms and fates of microplastics in the environment.”

Ingested microplastics can cause digestive and reproductive problems, as well as death, in fish, birds and other animals. Unhealthy additives in the plastic, including flame retardants and antimicrobials, have been associated with cancer and endocrine disruption in humans. Also, pollutants such as pesticides, trace metals and even pathogens can accumulate at high concentrations on microplastic particles.

Scientists have found microplastics nearly everywhere. Aside from rivers, microplastics are also common in lakes and oceans, in freshwater and marine fish, oysters and mussels, and in sediment. They are deposited onto land and water surfaces from the atmosphere.

The Great Lakes Restoration Initiative funded the new study. For more information on USGS microplastics research, please visit the USGS Great Lakes Restoration Initiative website.

Headline of the day: It’s about damn time


From teleSUR English:

 CEO’s Can Now Be Prosecuted Like War Criminals at the Hague

  • The International Criminal Court announced Thursday it will now hold corporate executives and governments legally responsible for environmental crimes.
  • The Hague court made explicit references to widening its approach to include land grabbing, which has allowed private corporations, with the help of governments, to take over large of areas of foreign land to exploit natural resources. It will also prosecute for environmental destruction.

DroughtWatch: California’s levels hold constant


Three months after the last downgrades, and California’s drought levels remain unchanged across the board, with all of the Golden State involved in one or another level of the official categories of water deprivation of the United States Drought Monitor:

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