Chapter 12 Climate and Glaciation Lonnie Thompson trekks

Chapter 10: Climate and Glaciation • No scientist has taken bigger risks above 18000

The Earth's Climate Jordan, The Essential Earth 1 e © 2008 by W. H.

The Earth's Climate • The climate includes many components of the Earth's system and

The Earth's Climate • The atmosphere is layered with different temperature values in each

Glaciers • The cryosphere comprises all of the ice on the Earth. Jordan, The

Glaciers • Most of the Earth's ice is found in Antarctic continental glacier. •

Glaciers • Greenland is the second largest glacier on Earth and with Antarctica cover

Glaciers • Snow melt is the source of much of the fresh water in

Glaciers • The cryosphere includes sea ice which grows in volume in the winter

Heat flowing out of Earth’s deep interior is only 0. 06 W/m 2. Solar

Heat and Radiation from the Sun • The Earth reflects radiation not absorbed by

The Balance of Heat Flow into/out of the Earth • Water vapor gives positive

What Would our Planet be like Without Greenhouse Gases ? • The Earth rotates

Local Climate Variations Jordan, The Essential Earth 1 e © 2008 by W. H.

Antarctic Ice Sheet • Today many scientists work to study ice cores in Anarctica

• Russian scientists at Vostok station carefully remove an ice core at 3500

Past Glaciation from Ice Cores Jordan, The Essential Earth 1 e © 2008 by

Climate has been relatively warm and stable during the last 10, 000 years. High

Glacial and Temperature Cycles • White shows evidence indicating the extent of the Wisconsin

Human activities release a total of 7. 1 Gt of carbon into the atmosphere

Temperature CO 2 concentration Years Jordan, The Essential Earth 1 e © 2008 by

CO 2 concentration (ppm) Northern Hemisphere temperature anomaly (°C) The 20 th-century is clearly

Arctic sea ice 1995 -2007 Jordan, The Essential Earth 1 e © 2008 by

Arctic sea ice 2005 -2007 4. 3 millionsq sqkm km Jordan, The Essential Earth

Receding Glacier South Cascade Glacier, Washingto Jordan, The Essential Earth 1 e © 2008

Meteorites found in Arctic Glaciers • The easiest place to locate dark, rocky meteorites

Global Warming • Global warming is a physical measurement that the Earth's surface temperatures

The Global Energy Challenge Roel Snieder Jordan, The Essential Earth 1 e © 2008

Developing countries Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman

… and our energy use Jordan, The Essential Earth 1 e © 2008 by

How do Geologist Find Old Glaciers Boundaries ? Glaciers leave clues. . . Jordan,

• Glacial striations on a rock from stones grinding at the base of

Glacial Characteristics • Glaciers flow downhill as a solid mass that creates channels, and

Erosional Landscapes • Erosional landforms produced by valley glaciers include: – U-shaped valleys –

Erosional Landscapes U-shaped valleys Hanging valleys Jordan, The Essential Earth 1 e © 2008

Glacial Deposits • Sediment-laden streams emerging from ends of glaciers have braided channel drainage

Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company

The History of Energy Consumption in the US over past 150 yrs How much

Peak oil N. B. based on USGS estimates, these are among the most optimistic

Declining production (1) resource depleted Jordan, The Essential Earth 1 e © 2008 by

Declining production (2) production gap! Jordan, The Essential Earth 1 e © 2008 by

Oil Peak, Oil Panic ? (Study by Amos Nur - Stanford) U. S. ,

Oil Consumption World wide by country The US uses more oil than all other

Countries with highest per capita income seeking oil from countri Jordan, The Essential Earthoil

New find in Gulf of Mexico (Jack No. 2 test well) • up to

Non-convenional reserves (excluding gas and coal) Jordan, The Essential Earth 1 e © 2008

Non-conventional oil 2 tons of tar sands produce 1 barrel of bitumen (~asphalt) Tar

Other Energy Resources • The metal uranium is used to power nuclear power generators

First solar 2 MW array Ft. Carson, CO Jordan, The Essential Earth 1 e

Research: efficient solar cells Jordan, The Essential Earth 1 e © 2008 by W.

Alternative Energy Sources: Wind power Jordan, The Essential Earth 1 e © 2008 by

What can I do as consumer? Lighting Transportation Jordan, The Essential Earth 1 e

What can I do as citizen? • Ask: what is our energy plan? •

Slides: 56

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Chapter 12: Climate and Glaciation • Lonnie Thompson trekks to Himalaya, the Andes, and beyond to study ice. Essential Earth 1 e © 2008 by W. H. Freeman and Company • Jordan, Do The you know why ? What is he studying ?

Chapter 10: Climate and Glaciation • No scientist has taken bigger risks above 18000 ft, risking blood clots, temporary blindness, frostbite, and hurricaneforce winds. • Risks to gather measurements and help us understand current climate trends. • Lonnie Thompson reconstructed a meticulous calendar of temperatures and dates from isotope measurements in ice. • He found that the Earth's frozen ice stores a history of climate changes as far back as 750, 000 yrs. Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company

The Earth's Climate • The atmosphere is layered with different temperature values in each • Temperatures in other Earth systems such as ocean water, Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company biosphere, lithosphere, & crysophere all contribute to an average

Glaciers • Greenland is the second largest glacier on Earth and with Antarctica cover 10% of the Earth's land mass. • These glaciers store 75% of the world's fresh water. • While Greenland has 2. 6 mill cubic km of ice, it is dwarfed by Antarctica which has 30 mill cubic km (90%) of the Earth's cryosphere. • Antarctica's ice is ~4000 m thick! Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company

Glaciers • Snow melt is the source of much of the fresh water in the hydrosphere. • Snowfall is 60 -70% of all annual precipitation which melts in spring into rivers and streams. Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company

Glaciers • The cryosphere includes sea ice which grows in volume in the winter and shrinks in the summer. • This satellite picture (left) shows sea ice flowing through the Bering Strait in May 2002. Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company

Heat flowing out of Earth’s deep interior is only 0. 06 W/m 2. Solar energy input to Earth’s surface is 342 W/m 2. Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company Therefore, heat radiating from Earth must balance solar input.

Heat and Radiation from the Sun • The Earth reflects radiation not absorbed by the atmosphere & surface • Strong greenhouse gases reflect this radiation back to the Earth and prevent it from leaving the atmosphere. Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company

The Balance of Heat Flow into/out of the Earth • Water vapor gives positive feedback, that is, it is a greenhouse gas and its presence prevents escape of the Earth's excess radiation. • Albedo gives positive feedback. Albedo measures the Sun's reflected energy from the cryosphere. As the Earths' temp rises, and glaciers melt, the albedo decreases. This process reduces reflected radiation escape. • Radiation damping can give negative feedback. Infrared energy escape is increased if temperatures rise. This process slows large temperature fluxuations and keeps the oceans from freezing or boiling off. • Plant growth gives negative feedback. Conversion of CO 2 into organic matter reduces greenhouse gasses in the atmosphere and allows for more escape of radiative energy. Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company

What Would our Planet be like Without Greenhouse Gases ? • The Earth rotates (1 day) much faster than the Moon (30 days) which evens out its temperature • The Moon's temp changes from 130 C in the day to -170 C at night! This would be very uncomfortable! • The Earth's glaciers increases its albedo to 31% where the Moon's albedo is only 7%. • However without any greenhouse gases, the Earth's surface temp would be very cold, -19 C (-2 F) and would freeze all our oceans. • Some greenhouse gases are necessary to moderate strong Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company fluctuations in surface temperature from Solar radiation

• Russian scientists at Vostok station carefully remove an ice core at 3500 m altitude (T is about -55 C !) • Below inspection of the core is done in a cold lab. Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company

Climate has been relatively warm and stable during the last 10, 000 years. High Key: Temperature CO 2 Methane Thousands of years before present Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company Relative carbon dioxide and methane concentrations Temperature relative to present climate (°C) There is a decline in both temperature and greenhouse gas concentrations during glacial periods… …and a rapid rise during deglaciation. Low

Glacial and Temperature Cycles • White shows evidence indicating the extent of the Wisconsin glacier in the Great Lakes during it's maximum about 18000 yrs ago and was ~3 km thick. Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company

Human activities release a total of 7. 1 Gt of carbon into the atmosphere each year. New plant growth and air-sea gas exchange remove 3. 8 Gt/yr, … ATMOSPHERE Fossilfuel burning (5. 3 Gt/yr) Land-use change: deforestation, agriculture (1. 7 Gt/yr) Land uptake By new plant growth (1. 9 Gt/yr) Terrestrial biosphere LAND Cement production (0. 1 Gt/yr) Fossil Rock organic carbonates carbon GEOLOGIC RESERVOIRS Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company Ocean uptake by air-sea gas exchange (1. 9 Gt/yr) OCEAN …yielding a net atmospheric increase of 3. 3 Gt/yr.

Temperature CO 2 concentration Years Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company CO 2 concentration (ppm) Global temperature anomaly (°C) A recent warming trend correlates with the increase in CO 2.

CO 2 concentration (ppm) Northern Hemisphere temperature anomaly (°C) The 20 th-century is clearly anomalous when compared with the last millennium. Temperature CO 2 concentration Years Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company

Meteorites found in Arctic Glaciers • The easiest place to locate dark, rocky meteorites is in Antarctic Ice Sheet • A small number of meteorites appear to have come from the Moon and Mars • Several of these appear to have come from Mars martian meteorite lunar meteorite Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company

Global Warming • Global warming is a physical measurement that the Earth's surface temperatures are rising beyond normal fluctuations. • Global warming can have many effects on our environment: - increase atmospheric temperature - melt glacial ice - prevent escape of the Sun's excess radiation - harm habitat environments like polar bears - create drastic changes in our climate (extreme hot and cold seasons) - and remove our only evidence of past climate history ! What can we do about this at home ? Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company

• Glacial striations on a rock from stones grinding at the base of a heavy ice sheet leave these shiny linear marks on the bedrock below. Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company

Glacial Characteristics • Glaciers flow downhill as a solid mass that creates channels, and walls made of ground up rock debris known as a merraine. Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company

Erosional Landscapes • Erosional landforms produced by valley glaciers include: – U-shaped valleys – Hanging valleys • Smaller tributary glacial valleys left stranded above more quickly eroded central valleys Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company

Glacial Deposits • Sediment-laden streams emerging from ends of glaciers have braided channel drainage patterns • Outwash landforms include drumlins, eskers, kettles and kames • Drumlins give can tell us what direction a glacier moved. Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company

Oil Peak, Oil Panic ? (Study by Amos Nur - Stanford) U. S. , Canada, Japan, Germany, France, Italy, UK, are the bigges consumers of© 2008 oilbyreserves worldwide. Jordan, The Essential Earth 1 e W. H. Freeman and Company

New find in Gulf of Mexico (Jack No. 2 test well) • up to 3 -15 billion barrels of oil • US consumption 20 million barrels/day • 5 months - 2 years • reservoir is 8 km under sea level Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company

Non-conventional oil 2 tons of tar sands produce 1 barrel of bitumen (~asphalt) Tar Sand Heavy Oil from National Geographic, June 2004 Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company Oil shale

Other Energy Resources • The metal uranium is used to power nuclear power generators – Found with organic matter in sedimentary rocks – Accounts for 10% of U. S. energy production – Leaves radioactive waste as by-product • Hydroelectric power provides about 4% of U. S. energy needs – Renewable and non-polluting • Geothermal power provides about 0. 2% of U. S. energy needs • Other renewable, non-polluting energy sources are wave/current power, solar power, wind power, and hydrogen fuel cells – As fossil fuel supplies dwindle, these sources become more important Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company

What can I do as citizen? • Ask: what is our energy plan? • Start a discussion in your community. • Demand that the United States becomes a world -leader in responsible use of energy. z Jordan, The Essential Earth 1 e © 2008 by W. H. Freeman and Company “That which we are, we shall teach, not voluntarily but involuntarily. ” [Emerson]