Author: Bruce E. Fleury
Last saved by: Fleury
Company: Microsoft

Global Environmental Change

EBIO 104

•	Dr. Bruce E. Fleury
•	Homepage: www.tulane.edu/~bfleury
•	Course homepage: 
	www.tulane.edu/~bfleury/envirobio/envirosci.htm

•	Office in Stern 4030
•	See syllabus for office hours
•	862-8290 (x8290 on campus), 865-5191 for EBIO office
•	bfleury@tulane.edu, or leave a message in my EBIO mailbox (Boggs 400)

•	Syllabus is online
•	Term list online for exams
•	Environmental links
•	Enviroweb - local environmental information

•	Exams - 3 hour exams (lowest grade dropped) plus a cumulative final
•	Each exam worth 100 points
•	Grade based on % of 300 points
•	NO makeup exams !

•	Readings from textbook shown on syllabus
•	Additional readings are on Blackboard
•	First outside reading assignment -
>	White, L. - The historical roots of our ecologic crisis

•	All preregistered students are in blackboard, others will be added as they register
•	Grades will be posted on Blackboard
•	I’ll also use Blackboard to email class announcements

•	Log on to Blackboard as soon as you can
•	Login with your Tulane userid and password
•	Problems with Blackboard should go to the Richardson Computer Lab Help Desk

•	
If the lecture notes are online, why do I need to come to class?
>	Even full files don’t contain all the multimedia etc. used in lectures
>	Lectures include more thorough explanations of novel or tricky concepts and terms

•	How to study for this class
>	Attend lectures regularly
>	Download lecture notes
>	Download and print the term list ASAP, use it to help complete your notes
>	Don’t fall behind!!

One more thing - 

NO CELL PHONES

 
 “Plus ca change, plus c’est la meme chose.” 

(The more things change, the more they remain the same.) 
						
				Alphonse Kerr

 

“There's never a new fashion but it's old.”
 
					Chaucer

•	These aphorisms refer to a paradox
•	Each generation discovers the wisdom of the ages
•	The same philosophies and fashions have been rediscovered over and over again - old wine in new bottles

“What has been is what will be, and what has been done is what will be done, there is nothing new under the sun.” 
 
					Ecclasiastes 1:9

•	True change is a more subtle thing 
•	Life and the world are in a constant state of flux - the world is a dynamic system
•	Even at the molecular level, motion is constant - atoms vibrate in place like a line of restless schoolchildren
 
“You cannot step twice into the same river, for other waters and yet others go ever flowing on.” 
 
					Heraclitus 

•	What is global change??
•	Global changes are changes that alter the fluids and gases of the atmosphere and oceans, and so are experienced everywhere on Earth 
•	Global change can affect the ability of the Earth to sustain life 

•	Global changes are also changes that occur locally (such as changes in the productivity or function of ecosystems) 
•	These local changes can become so widespread that they result in global change

•	Global change is a completely natural phenomenon
•	Why should we be concerned??
>	Human-induced changes have grown to equal the scale of natural changes
>	Human-induced changes may occur very rapidly

•	Global changes include

>	Changes in the composition of gases in the atmosphere 
>	Climate change - warming due to greenhouse effect 
>	Loss of the ozone layer and increased UV radiation 

•	Changes in the composition of gases in the atmosphere include 
>	Increases in carbon dioxide 
>	Changes in carbon isotope ratios 
>	Increases in compounds such as methane, oxides of nitrogen and sulfur, CFC’s

•	There is nothing wrong with carbon dioxide - it is an essential component of our global atmosphere
•	CO_2 in large quantities, however, causes global warming
•	There is nothing wrong with global warming  (say what??)

•	Without the greenhouse effect, surface temperatures would drop about 70 degrees…
•	So why all the fuss over global warming?

•	
In a relatively short time, we have added tremendous amounts of CO_2 to the atmosphere
•	In 1750, CO_2 concentrations hovered around 280 ppm
•	By 1988, CO_2 concentrations had topped 350 ppm due mainly to industrial activity

•	The same is true for most of our major environmental problems - too much of a good thing
•	In massive doses, even donuts would be deadly (but what a way to go…)

•	Nitrogen is an essential element in global cycles - found in most biomolecules (like DNA, proteins…)
•	Use of artificial fertilizers has reached the point where humans now dominate natural sources of nitrogen

•	In large quantities, nitrogen and phosphorous damage aquatic systems - eutrophication
•	Nitrogen is a limiting factor in the growth of aquatic algae and plants

•	Algal blooms form from excess nutrients
•	Decomposition of algae removes oxygen from the water
•	Massive amounts of N and P from agricultural runoff enters the Mississippi River, dump into the Gulf of Mexico

•	Dead Zone forms every summer in the Gulf of Mexico, a vast area devoid of life
•	Summer 2005 covered 4,564 mi^2
•	Summer 2006 covered over 6,700 mi^2 
•	Summer 2010 covered over 7,722 mi^2
•	Too much of a good thing!

•	Planetary systems are maintained in a delicate balance
•	Our species changes both the timing and magnitude of inputs and outputs in global cycles of matter and energy
•	We also alter sources (where things comes from) and sinks (where things ends up)

•	Global change is not necessarily a bad thing
•	In another 50 years, folks in North Dakota will be able to suntan without UV lamps
•	In another 50 years, you will need a wet suit and snorkel to explore the New York City subway system (which will be a lot safer…)

•	
Local changes can become global changes
>	Land conversion - changes in land use, development 
>	Loss of biodiversity - increased extinction rates due to habitat loss, human activities etc... 
>	Exotic species - introduction of non-native species with few or no local predators or diseases 

•	Local changes can become global changes
>	Changes in atmospheric chemistry due to local human activity
–	acid precipitation and dry deposition 
–	elevated tropospheric ozone (due to biomass burning, internal combustion engines, agriculture...)