Environmental News
Environmental News from Boulder, Colorado
CU scientists discover a new threat from air pollution
Aug 8th
tied to climate change and human health issues
An international research team led by the University of Colorado Boulder and the University of Helsinki has discovered a surprising new chemical compound in Earth’s atmosphere that reacts with sulfur dioxide to form sulfuric acid, which is known to have significant impacts on climate and health.
The new compound, a type of carbonyl oxide, is formed from the reaction of ozone with alkenes, which are a family of hydrocarbons with both natural and man-made sources, said Roy “Lee” Mauldin III, a research associate in CU-Boulder’s atmospheric and oceanic sciences department and lead study author. The study charts a previously unknown chemical pathway for the formation of sulfuric acid, which can result both in increased acid rain and cloud formation as well as negative respiratory effects on humans.
“We have discovered a new and important, atmospherically relevant oxidant,” said Mauldin. “Sulfuric acid plays an essential role in Earth’s atmosphere, from the ecological impacts of acid precipitation to the formation of new aerosol particles, which have significant climatic and health effects. Our findings demonstrate a newly observed connection between the biosphere and atmospheric chemistry.”
A paper on the subject is being published in the Aug. 9 issue of Nature.
Typically the formation of sulfuric acid in the atmosphere occurs via the reaction between the hydroxyl radical OH — which consists of a hydrogen atom and an oxygen atom with unpaired electrons that make it highly reactive — and sulfur dioxide, Mauldin said. The trigger for the reactions to produce sulfuric acid is sunlight, which acts as a “match” to ignite the chemical process, he said.
But Mauldin and his colleagues had suspicions that there were other processes at work when they began detecting sulfuric acid at night, particularly in forests in Finland — where much of the research took place — when the sun wasn’t present to catalyze the reaction. “There were a number of instances when we detected sulfuric acid and wondered where it was coming from,” he said.
In the laboratory, Mauldin and his colleagues combined ozone — which is ubiquitous in the atmosphere — with sulfur dioxide and various alkenes in a gas-analyzing instrument known as a mass spectrometer hooked up with a “flow tube” used to add gases. “Suddenly we saw huge amounts of sulfuric acid being formed,” he said.
Because the researchers wanted to be sure the hydroxyl radical OH was not reacting with the sulfur dioxide to make sulfuric acid, they added in an OH “scavenger” compound to remove any traces of it. Later, one of the research team members held up freshly broken tree branches to the flow tube, exposing hydrocarbons known as isoprene and alpha-pinene — types of alkenes commonly found in trees and which are responsible for the fresh pine tree scent.
“It was such a simple little test,” said Mauldin. “But the sulfuric acid levels went through the roof. It was something we knew that nobody had ever seen before.”
Mauldin said the new chemical pathway for sulfuric acid formation is of interest to climate change researchers because the vast majority of sulfur dioxide is produced by fossil fuel combustion at power plants. “With emissions of sulfur dioxide, the precursor of sulfuric acid, expected to rise globally in the future, this new pathway will affect the atmospheric sulfur cycle,” he said.
According to the U.S. Environmental Protection Agency, more than 90 percent of sulfur dioxide emissions are from fossil fuel combustion at power plants and other industrial facilities. Other sulfur sources include volcanoes and even ocean phytoplankton. It has long been known that when sulfur dioxide reacts with OH, it produces sulfuric acid that can form acid rain, shown to be harmful to terrestrial and aquatic life on Earth.
Airborne sulfuric acid particles — which form in a wide variety of sizes — play the main role in the formation of clouds, which can have a cooling effect on the atmosphere, he said. Smaller particles near the planet’s surface have been shown to cause respiratory problems in humans.
Mauldin said the newly discovered oxidant might help explain recent studies that have shown large parts of the southeastern United States might have cooled slightly over the past century. Particulates from sulfuric acid over the forests there may be forming more clouds than normal, cooling the region by reflecting sunlight back to space.
Most of the laboratory experiments for the study were conducted at the Leibniz-Institute for Tropospheric Research in Leipzig, Germany.
Co-authors on the study include Torsten Berndt and Frank Stratmann from the Leibniz-Institute for Tropospheric Research; Mikko Sipilä, Pauli Paasonen, Tuukka Petäjä, Theo Kurtén, Veli-Matti Kerminen and Markku Kulmula from the University of Helsinki in Finland; and Saewung Kim from the National Center for Atmospheric Research in Boulder. Mauldin also is affiliated with NCAR and the University of Helsinki.
The study was funded by the European Commission Sixth Framework program, the Academy of Finland, The Finnish Center of Excellence, the European Research Council, the Kone Foundation, the Väisälä Foundation, the Maj and Tor Nessling Foundation, the Otto Malm Foundation and the U.S. National Science Foundation.
City wants the public’s input on energy plans
Aug 2nd
Public input requested; help evaluate the work plan
The City of Boulder is asking for the public’s help in reviewing the draft work plan created to help guide the exploration of potentially forming a municipal electric utility. The city is strongly committed to ensuring a high level of community awareness and engagement throughout this important process, and is looking for effective ways to include community feedback.
The goal of the work plan is to guide the major tasks and activities that must be accomplished in order to deliver a recommended municipalization strategy to City Council.
The draft work plan is available on the Energy Future project website – www.BoulderEnergyFuture.com. Comments are due by 5 p.m. on Tuesday, Aug. 7. To provide input on the plan, use the project’s online comment form or send an e-mail to energyfuture@bouldercolorado.gov.
The draft work plan with community feedback incorporated will be presented to City Council at a Study Session on Tuesday, Aug. 28.
The city values our community’s perspectives and welcomes all feedback on the plan and project.
New edition of Energy Future newsletter available
The latest edition of Boulder’s Energy Future Today newsletter is now available online at www.BoulderEnergyFuture.com. Printed versions are available at various city buildings around town, including all libraries, recreation and senior centers, and the Municipal Building Lobby – 1777 Broadway. Articles in this edition include:
- A proposed strategy for enhanced Climate Action Plan (CAP) programs beginning in 2013
- Municipalization exploration update
- Your CAP tax dollars at work, specifically a finding by consultants about how the money has been spent to date
- An update on the Commercial Energy Efficiency Strategy
- Energy saving tips
Monthly newsletters will be created and distributed throughout the duration of the project. Sign up for the project e-mail list atwww.BoulderEnergyFuture.com to receive an electronic version of the newsletter and frequent project updates.
Second reading of the CAP tax renewal ballot language Aug. 7
City Council will hear the second reading of the proposed Climate Action Plan (CAP) tax renewal ballot language at 6 p.m. on Tuesday, Aug. 7, in City Council Chambers, 1777 Broadway. Public feedback will be heard at this meeting.
The current CAP tax, set to expire in March 2013, has been used to fund energy efficiency and conservation programs and services for residential, commercial and industrial electrical customers in Boulder for the past five years. These programs include EnergySmart and 10 for Change.
The city, with the help of consultants and the community, recently recommended a set of packages and programs that could be funded if the tax were renewed. Information on the recommended package and a historical analysis of CAP tax funds is available in the May 22 and July 24 information packets presented to City Council. Both packets and all consultant reports are available at www.BoulderEnergyFuture.com.
–CITY–
Population growth unsustainable, says CU prof, and the end will not be pretty
Jul 31st
In an educational video entitled “Population, Consumption, and Climate: A Conversation with Al Bartlett,” the professor reprises themes from his notorious talk on population. Bartlett came to CU-Boulder in 1950 to join the Department of Physics. In the 1950s and today, he notes society and governments view steady growth as the centerpiece of the global economy.
“I got to thinking about the fact that people didn’t really understand the arithmetic of steady growth,” he said. “So I put together a talk. I first gave it in September of 1969 on the arithmetic of growth.”
Bartlett has since delivered that well-known lecture more than 1,700 times to audiences worldwide. He often cites an analogy of human population growth and multiplying bacteria. Using an animation that shows bacteria doubling over a fixed period of time, the video illustrates the arithmetic of steady growth and how quickly resources are depleted as growth continues.
“There will be limits,” cautions Bartlett.
The world population topped 7 billion in March 2012, according to the United States Census Bureau. Bartlett explains that despite the fact that population growth rates in developing countries may be 3-4 times higher than the U.S. rates, a significant problem with population resides in the United States because of high per capita demand for energy and resources.
“The average child born in the United States will have, over its lifetime, 10-20 times the impact on world resources as a child born in an underdeveloped nation,” he says. “So we’ve got to address the problem at home.”
In addition to the strain on the earth’s natural resources, excessive consumption contributes to climate change because resource extraction, manufacturing, and transportation produce a great deal of carbon dioxide. And, according to Bartlett, “if any fraction of global warming can be attributed to the actions of humans, that’s all the proof you need to say the human population today is greater than the carrying capacity of the earth.”
Population, Consumption, and Climate: A Conversation with Al Bartlett is part of a video series viewable at Learn More About Climate, produced by CU-Boulder’s Office for University Outreach and Landlocked Films.
The Learn More About Climate initiative brings climate change-related information to communities across the state.The website is an online outreach tool that localizes climate change through interviews with leading scientists and everyday Coloradans to explain how climate change is affecting our state. The site also offers resources for teachers, students, policy makers, and community members who want to learn more about this critical issue.