Dear MEL Topic Readers,
Humans
accidentally canceled the next ice age — but it’s no reason to celebrate,
scientists say
An ice age
is a long period of reduced global temperatures where thick ice sheets and
glaciers expand across large areas of the Earth’s surface. It cycles between colder
glacial periods when ice sheets advance and warmer interglacial periods when
ice sheets retreat. The Earth is now in a warm interglacial period, and its
glacial stage is in the Little Ice Age that began in the 16th century.
The massive continental
ice sheet that covered North America 20,000 years ago shrank to a much smaller
ice cap in northernmost Canada. But about two millennia ago, it slowly began to
expand again, marking a new period of glaciation, an ice age. However, the ice
cap suddenly started to shrink around 1960, when summer temperatures rose due
to climate change caused by fossil fuel burning. Some geochemists believe that the
reversal is a sign that the then-about-to-happen glaciation, or ice age, was
halted by human activities. Some argue that the next ice age isn’t expected to start
for another 50 millennia. Humans have most likely affected climate change and caused
global warming. Have we also affected the ice age cycles?
Read the article
and learn about the signs of ice age cycles.