Multiple choice

1) Which of the following is NOT thought to have been a factor in triggering the onset of the most recent ice age, approximately 3 million years ago.

a) Plate tectonic processes that caused the N. and S. American continents to join together.

b) Negative feedbacks associated with plant growth and increased carbon dioxide.

c) Changes in ocean circulation patterns between and within the Atlantic and Pacific oceans.

2) The last 420,000 years have seen four long [ Select ] ["interglacial periods", "glacial periods"], each lasting approximately  [ Select ]  ["100,000 years", "50,000 years", "10,000 - 20,000 years"]  , when global temperatures were significantly  [ Select ]    ["warmer", "colder"] than today.

3) Glacial/interglacial cycles, as well as the shorter term climate fluctuations within them, are primarily controlled by ______.

a)  changes in atmospheric chemistry 

b) changes in Earth's orbital parameters, such as orbit shape and tilt

c) changes in the plate tectonic distribution of landmasses 

4) A light colored surface will reflect_________  sunlight/solar radiation, and is said to have a  _______ albedo.