Climate change a hot topic at STA gathering

Last week at the FivePine Conference Center, the Sisters Trails Alliance (STA) hosted the inaugural event in a new speaker series that they plan to hold on a quarterly basis. The series is designed to address local recreation opportunities, natural history, and related issues.

This first presentation in the series was titled "Changing Climate with Impact on Recreational Opportunities in Central Oregon" and featured geologist Bjarne Holm. Holm's talk focused on an historical look at climate change from a geological perspective, with a look at the growing impact of human activity on the environment.

Holm discussed factors that contribute to climate change and devoted a significant portion of the discussion to geophysics, the study of the physics of the Earth and its environment in space. He stated that climate changes have been apparent on Earth over much of the planet's history and that climate change will continue to occur.

He noted, however, that there is considerable evidence to indicate that some of the changes are being exacerbated by human activity. For example, he stated that, in addition to rapidly rising levels of carbon dioxide in the atmosphere, methane levels in Earth's atmosphere have risen 150 per cent - mostly due to human activity - just since the dawn of the Industrial Revolution.

Methane and carbon dioxide, he said, are principal components in the atmosphere that give rise to what we now hear referred to as the "greenhouse effect." As a preface to discussing the effects of greenhouse gasses on Earth, he cited the example of the atmosphere on the planet Venus. Specifically, he noted, even though the planet Mercury is much closer to the sun than Venus, Venus is actually the hotter planet of the two. This is because the naturally occurring greenhouse gasses trap the sun's heat like a giant blanket and prevent the dissipation of heat into space.

And, as greenhouse gasses increase, so it goes on Earth, as well - although certainly on a much smaller scale than on Venus. Still, Holm points out, the rising concentrations of greenhouse gasses on Earth have the same effect on our planet by trapping and retaining increasing portions of the sun's heat. That effect is what causes the frequently referenced, but less often understood, scientifically observed phenomenon now known as "global warming."

Holm is a geologist by profession, and he has worked much of his career in Alaska for the oil and natural-gas industry. Because of Holm's extensive geological work in Alaska, he has personally observed some of the significant effects of climate change in Alaska. As a result, he has had a front-row seat to some of the changes being wrought by warming temperatures on Earth.

During the course of his presentation, he showed numerous examples of how melting permafrost in the far north is changing the topography of Alaska. Examples included the loss of many northern lakes where melting permafrost is creating new subterranean channels, causing lakes and ponds to dry up.

He also showed photographs of the northwestern Alaskan fishing village of Shismaref, where thawing of the permafrost has resulted in extreme subsurface soil instability. Where once, the permafrost provided a firm foundation for the area, wave action is now causing the community to be quite literally washed away into the Arctic Ocean.

In another example, he reported experiencing 60-degree temperatures along a portion of the Iditarod Trail during the month of February of this year.

According to Holm, the current warming trend is likely to result in more extreme weather patterns, shortened ski seasons in our area, changes in the species makeup, more insect threats, increased fire risk, and increased allergen exposure. In summary, his view is that the predicted outlook is one that will present many challenges.

The current and possible future impacts of weather and climate change in Central Oregon have an important bearing on the future of outdoor recreation in the area, which is a concern of the STA. STA's mission includes the promotion and development of recreational opportunities in the Sisters area. The future of outdoor recreation in the area is a significant factor in the future of the organization.

For further information about STA trails and future programs, contact Ann Marland at 541-549-7006. Additional information about STA can also be found on their website at

www.sisterstrails.com.