The Changing Climate

I found two pages about climate change in a Reader's Digest Atlas, published 1987. That's one year before Hansen's US Senate committee testimony. Is that a good enough excuse? (The emphasis below is mine.)

The Changing Climate

We inhabit a thin, damp tissue of the atmosphere, where hospitable warmth and moisture are maintained in a critical balance. What we think of as the planet's "normal" weather patterns are typical only of the period in which we live.

Clues to the climate of the future lie in the facts of the past. There is every likelihood that the climatic conditions that gripped the Earth at the height of the last ice age 18,000 years ago will return one day. A drop in global average temperature of only 4°F (2°C) could initiate a new ice age. The advancing glaciers would imprison so much of the world's water that the oceans would shrink, stripping the seas from the continental shelves. New York City would lie under an ice sheet thick enough to bury the Empire State Building twice over. Montreal, Detroit, and Chicago would be entombed in snow, and the Midwestern prairies would survive only as wind-whipped steppe. Japan would become a peninsula of Asia, and you would be able to walk from England to France. On the other hand, some scientists believe that a rise of only a few degrees in global temperature would start a meltdown of the polar ice sheets and flood low-lying cities worldwide.

Many forces interact to create changes in the Earth's climate. These include tilts in the planet's axis and changes in its orbital path, sunspots that swell the stream of radiation emitted by the Sun, and spasms of volcanic activity that hurl veils of dust into the atmosphere.

1. ICE COVER. Ice sheets covered much of North America and Europe, New York, Berlin, Stockholm, Montreal, and Copenhagen would be buried beneath the ice if such conditions returned. 

2. CONTINENTAL CONNECTIONS. The sea level was lower, baring continental shelves and creating land bridges, Asian nomads migrated to America over the bridge that connected Siberia and Alaska. 

3. GREAT LAKE. Fed by melting snow from the Rockies, the now-vanished Lake Bonneville grew almost as big as today's Lake Michigan. 

4. DRY LAND. Monsoons were weaker than today, with the result that in West Africa the Sahara stretched farther south than its present extent. 

5. LARGER LAKES AND INLAND SEAS. Because of lower temperatures, there was less evaporation in arid lands, and some lakes and inland seas increased in size. 

6. POLAR HIGH. Vast high-pressure cells lingered over the polar ice sheets. Strong winds blew silt across the barren areas surrounding the ice and created dust storms.