Threats to the BiosphereThreats to the BiosphereBiologyBiology

BiosphereBiosphere

• The outer portion of Earth where all living organisms exist

- deepest ocean trench up into atmosphere

Since Industrial Revolution…Since Industrial Revolution…Earth’s global temperature is now Earth’s global temperature is now

at hottest point in 13,000 yearsat hottest point in 13,000 years

• What is this increase in temperature called?

• What is the name of this phenomenon?

• NOAA data 2010 link

• Global Warming is caused by the

Greenhouse Effect

• We now call global warming-

CLIMATE CHANGE

Greenhouse gasesGreenhouse gases

• Water Vapor H20• Carbon Dioxide CO2

• Methane CH4

• Nitrous Oxide NOx• Fluorocarbons CFC’s (part of Haloalkanes)• Ozone O3

• Which one above is the cause of global warming? ------

• Water Vapor H20 same levels

• Carbon Dioxide CO2 increased

• Methane CH4 doubled since 1800

• Nitrous Oxide NOx increased

• Fluorocarbons CFC’s now banned

• Ozone (STRATOSPHERIC) DROPPED

Evidence of stratospheric Evidence of stratospheric Ozone DepletionOzone Depletion

• link to ozone depletion movie

Depletion of Ozone LayerDepletion of Ozone Layer

• O3 is naturally occurring in Stratosphere

• Protects us from UV-B radiation

• Often called “good” ozone

““good” Ozone is depleted by CFC’sgood” Ozone is depleted by CFC’s

• Chlorofluorocarbons

• Used in older air conditioners, refrigerators, and in industry

Tropospheric OzoneTropospheric Ozone• “bad ozone” Formed from Nitrous

oxide (found in automobile exhaust) and VOC’s

• Unhealthy for many people• EPA issues ozone alerts for large cities

• Link to EPA Air Now current air quality map

Sources Sources of NOx of NOx

and and VOCVOC

Acid RainAcid Rain

• Rain is typically 5.0pH in Wisconsin, anything less than 5.4pH, we call it acid rain

• Where is acid rain a problem in U.S.?

• What causes Acid Rain?

Map of US acid rain depositionMap of US acid rain deposition

Illustration of acid rain productionIllustration of acid rain production

Is there a chemical that is a common Is there a chemical that is a common source of most threats to the source of most threats to the

Biosphere?Biosphere?• Hint: it is found in vehicle exhaust

•Nitrous oxides (NOx)

What can each of us do?What can each of us do?• Car pool, walk, ride bikes, use

public transportation, reduce, use less, change light bulbs to fluorescent or LED, use wind, solar, renewable fuels, drive smaller cars if possible, elect politicians that support global environmental policies

Current Arctic ice data Current Arctic ice data

• Data shows a continual reduction in Arctic Ice in recent years

• pp showing ice loss from 1979-2007

• NASA daily arctic ice data (ice movement) from 2005-2006

• NOAA model projections from 1900 through 2100