Environmental Engineering Reference
In-Depth Information
1941
2004
Picture 2.2
Retreat of Muir Glacier in Glacier Bay National Park in Alaska as seen in 1941 (
top
) and
2004 (
bottom
).
Top, by W. O. Field; bottom, by B. F. Molnia. Courtesy of the National Snow and Ice Data Center/World Data
Center for Glaciology, Boulder, Colorado.
point out that the planet moves though slow cycles and the events that shaped the planet and
created the living conditions we have today, including the atmosphere, have taken hundreds of
millions of years in the making. Human activity, on the other hand, has taken just a couple of
hundreds years to significantly alter the Earth's conditions. Will there be any repercussions as
a consequence of the changes created by human activity? It is likely, but no one knows the
exact extent. So until there are definite answers, it would probably be smart to err on the safe
side and be more proactive in our actions, for instance, by developing a low-carbon economy.
Finding alternatives to fossil fuels would not only mitigate the potential threat of carbon
dioxide emissions into the atmosphere, but it would also create a more sustainable system.
