Threats to the Biosphere powerpoint


Threats to the Biosphere


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 caused by the is

Greenhouse Effect

We now call global warming-


Greenhouse gases • • • • • • Water Vapor H 2 0 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 Carbon Dioxide CO Methane CH


4 2 0 Nitrous Oxide NOx 2 Fluorocarbons CFC’s

doubled since 1800 (STRATOSPHERIC) same levels increased increased now banned 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 • C






• 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 5.0pH 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 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 through 2100 from 1900