
Future Earth Steve Dutch University of Wisconsin-Green Bay
Why Look Ahead? • Usually picture geologic time by looking back • New Perspective • Can you picture the U.S. in 1000 years? • That’s an instant in geologic time • Human activities are ephemeral compared to geologic time
1000 Years • 5-7 M=8 quakes on San Andreas • New Madrid and Cascadia quakes • 10 Cascades eruptions • Mississippi delta shift • Niagara Falls retreats 900 meters • Hawaii moves 90 meters • Probable damaging meteor impact • One or more supernovas
Humans in 1000 years • Probably many cities and nations will still be extant
10,000 years • 50-70 M=8 quakes on San Andreas • 100 Cascades eruptions • 10-20 Mississippi delta shifts • Niagara Falls retreats 9 kilometers • Hawaii moves 900 meters • Probable meteor impact with regional effects • Hudson’s Bay and Baltic drained • Dozens of Supernovas • Earth axis tilt 22-1/2 degrees
Humans in 10,000 years • In 8,000 years we got from proto-Indo-European to English, Latin and Russian • Time enough for new languages to evolve • Will any word in any language still survive?
100,000 years • San Andreas shifted by 2.5 kilometers • 1000 Cascades eruptions • 100-200 Mississippi delta shifts • Niagara Falls retreated to Lake Erie • Loihi reaches surface? • Numerous meteor impacts with regional effects probable • Next ice age? • New stars may form
Humans in 100,000 years • Time enough to develop our civilization from Paleolithic technology • Fewer natural resources but… • Old human deposits may be better sources than rocks
1,000,000 years • San Andreas shifted by 25 kilometers • Large new Cascades volcanoes • 1000-2000 Mississippi delta shifts • Ten ice ages? • Loihi and Kilauea as large as present Mauna Loa • Several collapses of Hawaiian shields • Several supervolcano eruptions • Meteor impact with global effects probable
Humans in 1,000,000 years • Human race itself may evolve • If society collapses long enough, different gene pools may speciate
What Will Endure 1,000,000 years? • Steel corrodes • Titanic and Arizona will be gone in 1000 years. • Most likely to survive: no steel, solid • Highway and canal cuts • Earth fill dams • Open pit mines and mine dumps • Large monuments (Mount Rushmore, Pyramids)
What Will They See of Us? • Pleistocene mass extinction • Rapid global spread of human artifacts, reduction of forests, and spread of domestic animals • Sixth Extinction? • Many endangered organisms would never show up in fossil record • Caution in comparing present extinctions with past • Our choice
Long-Term Climatic Trends • Brightening of the Sun • Capturing of CO2 by carbonate rocks? • Moist greenhouse effect • Runaway CO2 Greenhouse Effect • Venus conditions
Planetary Habitable Zones • Primarily in the Liquid Water Zone • Can’t be too warm • Water Vapor in upper atmosphere broken down by solar UV and charged particles (photodissociation) • Hydrogen escapes to space
The Ultimate Long-Term Forecast • Slow warming trend for the next billion years • Increasing humidity • CO2 decrease leads to extinction of plants? • Boiling and evaporation of the oceans
The Oreo Model of Life History • Micro-organism Earth (0-3 billion years) • Multicellular Earth (3-5 billion years) • Micro-organism Earth (5-6 billion years) • “The white creamy middle”