CHAPTER FIVE
LONG-TERM CLIMATE VARIATIONS

SECTION ONE

NOAA Paleoclimatology Program
HTML NOAA
The NOAA Paleoclimatology Program provides access to many different types of paleoclimate reocrds.

Sunspot Numbers
GIF National Solar Observatory
Monthly averages of sunspots from 1954 to present.

Sunspot Numbers
HTML World Data Center-A for Solar-Terrestrial Physics
Explanation of Sunspots and annual sunspot numbers f rom 1700 to present.

Sunspot Cycle
GIF Space Science Group of Olou Finland
Sunspot Cycle from 1749 to today

SECTION TWO

Ice Ages
HTML Illinois State Museum
The Illinois State Museum has an interesting interactive exhibit of the conditions likely to have been present in the Midewestern United States 16,000 years ago. Other information includes a short video clip of the retreat of the ice sheet over North America.

Oxygen isotope Ice Volume Proxy
GIF Rice University

SECTION THREE

Milankovitch Hypothesis
HTML Illinois State Museum
The Illinois State Museum also provides additional information incuding other schematics of the Milankovitch hypothesis.