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A new UCLA study suggests the rapid growth of a huge northern bog complex may have helped activate global warming around the time of the ice age. The study may provide insight into current concerns about the impact of global warming on the planet.

Peat bogs, which are masses of organic matter such as leaves and plants, cause plant material to decay without oxygen, and as a result release methane gas into the atmosphere. Peat bogs also play a role in the exchange of carbon dioxide, another greenhouse gas.

The findings not only dispel previous assumptions of bogs, but also reveal the environment’s potential to change drastically over a short period of time.

“Northern bogs are not only older than we had previously thought, but they developed really quickly,” said Dave Beilman, a researcher in the UCLA geography department and study co-author.

The scientists of the study believe the gases released by the bogs may have contributed to global warming that led to the melting of the ice glaciers during the ice age about 11,000 years ago.

“This study shows that these kinds of northern bog environments have played a large part in greenhouse gas dynamics,” Beilman said.

The greenhouse effect is the process in which the absorption of radiation by an atmosphere warms a planet.

“Gases in the atmosphere trap radiation that would otherwise get out of the atmosphere and cool the Earth,” said David Neelin, a professor in the department of atmospheric and oceanic sciences.

One of the most important of these gases is carbon dioxide, which can be emitted by human activities including the burning of fossil fuels such as oil and coal, he said.

Through studies of trapped air bubbles in the arctic ice, the concentration of carbon dioxide over thousands of years can be measured and a recent increase in carbon dioxide can be observed, Neelin added.

“Greenhouse gases all interfere in the Earth energy budget in a way that tends to warm the planet as a whole because (heat) ... is less easily able to get to space and is trapped in the atmosphere,” Neelin said.

But some experts say current human activities as well as agricultural and industrial by-products are contributing to global warming.

Yongwei Sheng, a UCLA assistant professor of geography who was on the team that led the study, said human and physical factors interact together to cause global warming.

“The human factors release carbon dioxide into the atmosphere, increasing the temperature in different areas of the world. ... In the arctic, snow caps, which reflect energy, will melt. As a result, more energy will be absorbed (into the ground),” he said.

Depending on how hot and dry or cool the peat lands are, carbon dioxide can either be taken up or released, Beilman said.

Consequently, these greenhouse gases can lead to the warming of the Earth.

“Once we have these greenhouses accumulated in the atmosphere it is something like a layer of glass – solar radiation passes through and the radiation cannot get out from there. So the heat accumulates, increasing the temperature,” Sheng said.

Methane would be released at a higher rate if temperatures increase, he added.

But scientists are unsure of whether these masses of organic material pose a significant threat.

“The million-dollar question is whether these bogs will exacerbate global warming,” Bielman said. “They have a dual role in greenhouse gas dynamics; on one hand, they exchange carbon dioxide with the atmosphere; on the other hand, they are the single largest natural source of methane (emission).”

The study also exposed the lack of knowledge of the arctic environment, where a third of the world’s soil carbon is stored in the bogs, he said.

UCLA scientists have been studying the arctic region for over 30 years and have found that more than 100 arctic lakes have disappeared, Sheng said.

“The reason is not due to evaporation. ... These lakes sank into the soil because the lake bed (made of permafrost) is no longer solid because of global warming,” he said.

“Our conclusion was that if the arctic warming trend continues we’re going to see more lakes disappear and that will affect a lot of species,” he added.

Scientists remain unsure as to whether the temperature will increase high enough to kill off species in the next century.

However, people can personally help decrease their contribution to the greenhouse effect, for instance, by reducing their energy use with driving a small or hybrid car, not traveling more than they need to, turning off their lights, and not using air conditioning unless necessary, Neelin said.