ESS101C
Prof.
Jin-Yi Yu
Resolution of Ice Records
qAnnual layer of snows are visible at the surface of many
mountain glaciers and rapidly deposited ice sheets.
qAs snow is buried
and slowly recrystallized into ice, annual layers remain resolable
to a depth. Below this depth, the layering is lost.
qIce cores from
mid-latitude ice sheets such as the one on Greenland, where deposition of snow
is rapid, the annual layering may remain visible tens of thousands of year
into the past.
qIce cores from
Antartica, where only a small amount of snow accumulates each year, annual
layering may not occur even at the ice surface.
(from Earth’s Climate: Past and Future)