So we know the earth is getting warmer at a rapid rate, and that the temperature increase is due to the accumulation of greenhouse gases in the atmosphere. What are the sources of these gases?
Combustion of fossil fuels (oil, gas and coal) for energy use is the primary source of greenhouse gases and, in particular, carbon dioxide. Carbon dioxide is currently the most significant greenhouse gas because it represents nearly 75 percent of global greenhouse gas emissions.
Since the late 1800s rising global temperatures correlate directly with rising carbon dioxide levels from fossil fuel emissions. The current level of atmospheric carbon dioxide has not been seen on earth for at least 800,000 years.
There are other important contributors to elevated greenhouse gas levels including land use changes, forestry practices, agricultural and livestock production, landfill emissions, and various industrial processes.
Climate change is defined as the long-term alteration of temperature, precipitation and typical weather patterns. Certainly the earth has experienced naturally caused climate change many times before. The ice ages are a familiar example. However, the abnormally high carbon dioxide levels we have now are driving a much more rapid rate of change than has occurred since humans have been on planet earth.
Studies show that the earth is going through one of the most extreme changes in climate seen in the last 65 million years, and that the change is occurring 10 times more rapidly than it has in the past.
Besides temperature and precipitation changes, other profound climate change effects include rising sea levels, warming ocean temperatures, ocean acidification, melting of sea and glacial ice in the polar regions, and thawing of the tundra’s permafrost layer. Some of these changes will further accelerate warming.
In addition, climate change will affect many plant and animal species, and the ecosystems on which they depend.
Although we cannot completely avoid the effects of the climate changes already set in motion, we can prevent the worst potential outcomes by acting now.
In future articles we will explore how climate change is likely to affect Montana and how we can individually and collectively work on strategies that will protect the planet and possibly even improve our lives.
The author is a member of the Kootenai Climate Group.