Threats to the Biosphere Biology Biosphere The outer

Threats to the Biosphere Biology

Biosphere • The outer portion of Earth where all living organisms exist deepest ocean trench up into atmosphere

Since Industrial Revolution… Earth’s global temperature is now at 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 gases • • • Water Vapor H 20 Carbon Dioxide CO 2 Methane CH 4 Nitrous Oxide NOx Fluorocarbons CFC’s (part of Haloalkanes) Ozone O 3 • Which one above is the cause of global warming? ------

• • • Water Vapor H 20 same levels Carbon Dioxide CO 2 increased Methane CH 4 doubled since 1800 Nitrous Oxide NOx increased Fluorocarbons CFC’s now banned Ozone (STRATOSPHERIC) DROPPED

Evidence of stratospheric Ozone Depletion • link to ozone depletion movie

Depletion of Ozone Layer • O 3 is naturally occurring in Stratosphere • Protects us from UV-B radiation • Often called “good” ozone

“good” Ozone is depleted by CFC’s • Chlorofluorocarbons • Used in older air conditioners, refrigerators, and in industry

Tropospheric 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 of NOx and VOC

Acid Rain • Rain is typically 5. 0 p. H in Wisconsin, anything less than 5. 4 p. H, we call it acid rain • Where is acid rain a problem in U. S. ? • What causes Acid Rain?

Map of US acid rain deposition

Illustration of acid rain production

Is there a chemical that is a common source of most threats to the Biosphere? • Hint: it is found in vehicle exhaust • Nitrous oxides (NOx)

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 • 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