How does studying Mars advance our understanding of the Earth’s atmosphere as forests keep burning, causing hazardous air quality and “Mars-like skies”?
Former NASA scientist Joel S. Levine, who is currently serving as research professor in the William & Mary applied science department, has joined W&M News to discuss the impacts of wildfires and biomass burning.
Levine is a planetary scientist with exceptional expertise in the atmospheres of Earth and Mars. He has served as author or editor for seven books: Three on biomass burning and global change, one on atmospheric chemistry, two on the human exploration of Mars and the last on the return of humans to the Moon. He has also authored over 175 journal articles, scientific reports and book chapters.
The interview has been edited for clarity.
Q. How does studying the atmosphere of Mars advance our understanding of the Earth’s atmosphere?
A. By studying the atmosphere of Mars and its composition, chemistry and dynamics, we learn much about the Earth’s atmosphere and climate. For example, in its early history, some 4.6 billion years ago, Mars was very Earth-like. It was a warm planet with abundant amounts of liquid water in the form of oceans several miles deep in the Northern Hemisphere and rivers and lakes covering the entire planet. Today, Mars is a cold planet completely devoid of liquid water on its surface. Why? That’s a good question and one of the reasons that we are sending humans to Mars as early as the late 2030s.
Q. Why is this biomass burning important to NASA?
A. For many years, NASA’s Biomass Burning Research Program, for which I served as principal investigator, measured the particulate and gaseous products of biomass burning in the many different ecosystems of our planet. Understanding and protecting the environment of the Earth and its atmosphere and climate is listed on the NASA charter. The atmosphere and climate are truly global issues, and NASA is the agency in the U.S. government that has the capability of monitoring/measuring the Earth on a global basis with its many Earth-orbiting satellites.
I am happy to report that under my supervision, a half dozen William & Mary graduate students in the Department of Applied Science completed their doctoral research on the investigations obtained by the NASA Biomass Burning Research Program on the global impact of biomass burning and the Kuwaiti Oil Fires.
Q. You have researched biomass burning globally. What are the main similarities and differences across the world?
A. Biomass burning is truly a global environmental problem that will increase in the future as our planet heats up and there are more wildfires on our planet. However, different ecosystems have different types of biomass material and burn at different temperatures depending on the nature of the biomass burning and hence, produce slightly different ratios of combustion products.
Q. Why is wildfire smoke hazardous?
A. Wildfire smoke contains both solid particles, called aerosols, and gases resulting from the combustion of the biomass material in, for instance, trees and grasses.
Combustion solid particles are a serious health issue. They may cause respiratory problems, even in the longer term, and eye irritation problems.
The gases produced by the combustion of wildfires include carbon dioxide, carbon monoxide and the oxides of nitrogen. Carbon dioxide is an important greenhouse gas; the oxides of nitrogen chemically form the gas ozone, which is an irritant, near the Earth’s surface.
Beyond affecting local air quality, wildfires can affect the global atmosphere by producing large amounts of carbon dioxide.
Q. Biomass burning is sometimes promoted as a “clean” source of energy — is this true?
A. Biomass burning is not a “clean” source of energy production. Biomass burning produces aerosols or solid particulates and several environmentally significant gases such as carbon dioxide and the oxides of nitrogen.
Q. How does climate change affect the occurrence of wildfires?
A. As the Earth heats up due to global warming, which is controlled to a very large degree by the gas carbon dioxide, the world’s forests and grasslands will burn with greater frequency and more easily.
Q. How far can smoke from a wildfire travel, and why does it change the color of the sky?
A. Smoke from wildfires can travel thousands of miles around our planet. Precipitation will tend to cleanse clear the atmosphere of the particulate material resulting from the combustion of biomass.
The solid particulates produced by biomass burning result in the sky turning red and orange due to the absorption and scattering of sunlight in the presence of the aerosols.
Q. What can people do to limit damage?
A. People, especially elderly people, should avoid long exposure to wildfire smoke by remaining indoors during wildfires episodes. Masks will be helpful especially for elderly people and people suffering from asthma.
Q. How accurate can predictions of air quality be? What are the challenges?
A. It is difficult to accurately predict air quality produced by wildfires since it is difficult to predict the movement of air masses as they leave a wildfire. Most wildfires generate so much energy of combustion that they produce their own local meteorology (wind patterns, circulation patterns) and impact the normal flow of the atmosphere.
Antonella Di Marzio, Senior Research Writer