Purdue Researchers Part of Volcanic Eruptions
Marc Caffee, professor of physics, was part of an international study that found
volcanic eruptions have been responsible for cooling extremes recorded since early
The study, which was led by scientists at the Desert Research Institute, reconstructed the timing and associated radiative forcing of nearly 300 individual volcanic eruptions within the past 2,500 years. The researchers found that large volcanic
eruptions were a dominant driver of climate variability, as the volcanic sulfate and
ash ejected into the upper atmosphere shielded the Earth’s surface from incoming
solar radiation. The eruptions led to widespread summer cooling extremes and
climate change that has been tied to pandemics and famines in the 6th century,
The researchers studied the volcanic sulfate and other chemicals in ice cores taken
from ice sheets in Greenland and Antarctica. The paper was published in the journal
Nature in July and is available online.
Collaborating with Thomas Woodruff, a postdoctoral researcher, Caffee used a
tandem electrostatic accelerator to perform measurements of beryllium- 10 in individual layers of ice within the ice core.
“Anomalies in the deposition of beryllium- 10 in the ice layers allowed us to establish
a more precise timeline than was possible with previous studies,” says Caffee, who
directs the Purdue Rare Isotope Measurement Laboratory (PRIME lab). “This ice
core chronology, in turn, was used to precisely date the volcanic eruptions. What is
exciting about this work is the ability to date events nearly to the year. This gives us
the real opportunity to look for cause and effect relationships.”
Ag Researcher to Explore
Compounds in Mint Plants
A Purdue University biochemistry
professor has received a $1.4 million
National Science Foundation (NSF)
grant to conduct mint research. Natalia
Dudareva, distinguished professor of
biochemistry, is part of a research team led
by Michigan State University that received
a $5.1 million NSF grant.
Mints, or Lamiaceae, are the world’s sixth-largest family of flowering plants,
and Dudareva’s research will focus on identifying chemical compounds and
their formation in 14 different species. Findings will allow researchers to
produce the compounds and increase their levels in plants. The research also
could lead to uses for plants of the mint family, such as for medicinal purposes.
“This research is not only important for the mint industry, but also for agricul-
ture and medicine as plant species in this family
produce a wide range of metabolites used as
food additives, medicinal compounds and
other industrial purposes,”
Robin Buell, MSU plant
biologist and leader of
the grant, says that mint
belongs to one of the most
fascinating families of plants.
“We use them in cooking, for fragrance, for furniture, as ornamentals, for feline intoxicants and as herbal remedies — all because they produce diverse chemicals of interest to humans,” Buell says.
Little is known about mints, however, in comparison to their worldwide economic value. In the U.S. alone, peppermint and
spearmint oil sell for $20 to $24 per pound and had a total estimated market value of $200 million in 2012.