the explorers journal the climate change issue - The Explorers Club

MICROBES ON THE ROCKS
Germs frozen in glaciers for millions of years
might revive as global warming melts the icecaps.
Scientists investigated samples of the oldest known
ice on Earth, which lies frozen in the Dry Valleys of
the Transantarctic Mountains. After melting five
ice blocks 100,000 to 8 million years old, Rutgers
University marine microbiologist Kay D. Bidle
and his colleagues found microbes in all the ice and
grew them in the lab, the first time scientists have
ever resurrected such ancient, frozen life.
While the young microbes grew very quickly,
doubling in number every couple of days, the
older samples grew very slowly, doubling only
every 70 days. Genetic analysis revealed the older
DNA had deteriorated significantly, likely due to
cosmic rays destroying it over time.
While more ancient germs might not last
past especially long deep freezes, their DNA still
could. The researchers —whose findings are described
online in the Proceedings of the National
Academy of Sciences—suggest that as global
warming melts the ice, prehistoric microbes or
genes could flow into the seas, altering the evolution
of microbes in the oceans.
—CHARLES Q. CHOI
30
activity. This alarming trend is a critical finding that
is now reshaping politics and becoming a factor in
both our health and our economy. Without intervention,
it will increasingly determine our overall
quality of life. However, it is important to remember
that we have options.
While there is no quick fix for our environmental dilemma,
there clearly needs to be action. Immediate
reduction in the emissions of greenhouse gases
such as CO 2
and CH 4
will reduce the time it takes
the planet to recover, the severity of future change,
and the probability of climate surprises. Immediate
and more stringent reductions in the emissions of
toxic metals and acid rain, for example, will yield
a cleaner and healthier environment in months to
years depending upon the degree of restriction.
While it is certainly true that legislation will lay a major
foundation for a cleaner, healthier environment,
it will also depend to a large degree on the actions
of those in the private and public sectors.
Our future could be one characterized by energy
efficiency and a return to more natural states of the
atmosphere. We have the ice cores to set our standards.
The decision is ours and the opportunities
for creativity in technology and lifestyle could drive
us toward an amazing future.
Acknowledgments
U.S. research in the Arctic and Antarctica is supported by the
Office of Polar Programs of the National Science Foundation.
Our research has been made possible through the combined
efforts of national agencies such as the National Science
Foundation; logistics support provided by the U.S. Navy
and U.S. Air National Guard; help from contractors such as
Raytheon Polar Services and VECO; the Scientific Committee
for Antarctic Research (SCAR); and the efforts of the international
scientific community.
biography
A Fellow of The Explorers Club and director of the Climate
Change Institute at the University of Maine, Paul Andrew
Mayewski has led more than 45 expeditions to the Arctic,
Antarctic, Himalayas, and the Andes. Co-author of The
Ice Chronicles, Mayewski received the first SCAR Medal
for Excellence in Antarctic Research in 2006. In October,
Mayewski and colleagues will carry the Explorers Club Flag
as they undertake an over-snow traverse to the South Pole to
collect ice cores and pursue related glaciological research.
Dramatic human impact on the chemistry of the atmosphere over the past few decades compared to the last 5000 years as
inferred from ice core records. Data for this figure from: Petit et al., 1999, Nature; Indermuhle et al., 1999, Nature; Etheridge
et al., 1996, Journal of Geophysical Research; Blunier et al., 1995, Nature; Etheridge et al., 1998, Journal of Geophysical Research;
Chappallez et al., 1999, Nature; Leuenberger and Sigenthaler, 1994, Trends; Etheridhe et al., 1994, Trends; Kang et
al., 2002, Atmospheric Research; Mayewski et al., 1986, Science; 1990, Nature; Hong et al., 1994, 1996, Science; Schuster et al.,
2002, Environmental Science and Technology.