Environmental science is the study of how humans interact with their environment. It is an interdisciplinary field that uses natural and social sciences to understand the natural world and develop solutions to environmental problems. Some of the major challenges we face include pollution, climate change, loss of biodiversity, and depletion of natural resources. Achieving sustainability is an important goal that requires meeting environmental, economic and social needs without compromising future generations. Environmental science aims to help address these challenges through gaining knowledge and finding balanced solutions to environmental issues.

1. Environmental ScienceEnvironmental Science

2. What is EnvironmentalWhat is Environmental
Science?Science?
The study of how humans interact withThe study of how humans interact with
their environmenttheir environment
Our environment is everything that
surrounds us, both natural and man-
made.

3. Environment: the total of ourEnvironment: the total of our
surroundingssurroundings
• All the things around us with whichAll the things around us with which
we interact:we interact:
• Living thingsLiving things
• Animals, plants, forests, fungi, etc.Animals, plants, forests, fungi, etc.
• Nonliving thingsNonliving things
• Continents, oceans, clouds, soil, rocksContinents, oceans, clouds, soil, rocks
• Our built environmentOur built environment
• Buildings, human-created living centersBuildings, human-created living centers
• Social relationships and institutionsSocial relationships and institutions

4. Natural resources: vital to human survivalNatural resources: vital to human survival
• Renewable resourcesRenewable resources::
• Perpetually available: sunlight, wind, wave energyPerpetually available: sunlight, wind, wave energy
• Renew themselves over short periods: timber, water, soilRenew themselves over short periods: timber, water, soil
• These can be destroyedThese can be destroyed
• Nonrenewable resourcesNonrenewable resources: can be depleted: can be depleted
• Oil, coal, mineralsOil, coal, minerals
Natural resources = substances and energy sources
needed for survival

5. • “…“…the earth enables our people to survive,the earth enables our people to survive,
the environment must be respected andthe environment must be respected and
maintained. As long as the earth remainsmaintained. As long as the earth remains
healthy, the people remain healthy.” (healthy, the people remain healthy.” (LongLong
and Fox, 1996)and Fox, 1996)

6. Global human population growthGlobal human population growth
• More than 6.7 billionMore than 6.7 billion
humanshumans
• Why so many humans?Why so many humans?
• Agricultural revolutionAgricultural revolution
• Stable food suppliesStable food supplies
• Industrial revolutionIndustrial revolution
• Urbanized societyUrbanized society
powered by fossil fuelspowered by fossil fuels
• Sanitation and medicinesSanitation and medicines
• More foodMore food

7. • Human population growthHuman population growth
exacerbates all environmentalexacerbates all environmental
problemsproblems
• The growth rate has slowed…butThe growth rate has slowed…but
we still add more than 200,000we still add more than 200,000
people to the planet each daypeople to the planet each day WeWe
depend completely on thedepend completely on the
environment for survivalenvironment for survival
• Life has become more pleasantLife has become more pleasant
for us so far (Increased wealth,for us so far (Increased wealth,
health, mobility, leisure time)health, mobility, leisure time)
• But…natural systems have beenBut…natural systems have been
degraded and environmentaldegraded and environmental
changes threaten long-termchanges threaten long-term
health and survivalhealth and survival

8. BrainstormBrainstorm
• With your partner/group, brainstorm atWith your partner/group, brainstorm at
least 10 ways in which destruction to theleast 10 ways in which destruction to the
environment and depletion of resourcesenvironment and depletion of resources
can affect our overall well being as acan affect our overall well being as a
populationpopulation

9. Environmental science: how doesEnvironmental science: how does
the natural world work?the natural world work?
EnvironmentEnvironment  impactsimpacts 
HumansHumans
• It has an applied goal:It has an applied goal:
developing solutions todeveloping solutions to
environmental problemsenvironmental problems
• An interdisciplinary fieldAn interdisciplinary field
•Natural sciences:Natural sciences:
information about the worldinformation about the world
•Social sciences: valuesSocial sciences: values
and human behavior,and human behavior,
politics, economy, etc.politics, economy, etc.

10. What is an “environmentalWhat is an “environmental
problem”?problem”?
• The perception of whatThe perception of what
constitutes a problem variesconstitutes a problem varies
between individuals andbetween individuals and
societiessocieties
• Ex.: DDT, a pesticideEx.: DDT, a pesticide
• In developing countries:In developing countries:
welcome because it killswelcome because it kills
malaria-carrying mosquitoesmalaria-carrying mosquitoes
• In developed countries: notIn developed countries: not
welcome, due to health riskswelcome, due to health risks

11. Environmental science is notEnvironmental science is not
environmentalismenvironmentalism
•Environmental scienceEnvironmental science
• The pursuit of knowledgeThe pursuit of knowledge
about the natural worldabout the natural world
• Scientists try to remainScientists try to remain
objectiveobjective
•EnvironmentalismEnvironmentalism
• A social movementA social movement
dedicated to protecting thededicated to protecting the
natural worldnatural world

12. The “ecological footprint”The “ecological footprint”
• The environmental impact ofThe environmental impact of
a person or populationa person or population
• Amount of biologicallyAmount of biologically
productive land + waterproductive land + water
for raw materials and tofor raw materials and to
dispose/recycle wastedispose/recycle waste
• OvershootOvershoot: humans have: humans have
surpassed the Earth’ssurpassed the Earth’s
capacitycapacity
We are using 30% more of the planet’s resources than
are available on a sustainable basis!

13. Ecological footprints are not allEcological footprints are not all
equalequal
• The ecologicalThe ecological
footprints of countriesfootprints of countries
vary greatlyvary greatly
• The U.S. footprint isThe U.S. footprint is
almost 5 times greateralmost 5 times greater
than the world’sthan the world’s
averageaverage
• Developing countriesDeveloping countries
have much smallerhave much smaller
footprints thanfootprints than
developed countriesdeveloped countries

14. What are the challenges weWhat are the challenges we
face?face?
• What are the environmental issues weWhat are the environmental issues we
are facing today?are facing today?
• Come up with at least 10!Come up with at least 10!

15. We face challenges in agricultureWe face challenges in agriculture
• Expanded food production led toExpanded food production led to
increased population andincreased population and
consumptionconsumption
• It’s one of humanity’s greatestIt’s one of humanity’s greatest
achievements, but at an enormousachievements, but at an enormous
environmental costenvironmental cost
• Nearly half of the planet’s landNearly half of the planet’s land
surface is used for agriculturesurface is used for agriculture
• Chemical fertilizersChemical fertilizers
• PesticidesPesticides
• ErosionErosion
• Changed natural systemsChanged natural systems

16. We face challenges in pollutionWe face challenges in pollution
• Waste products and artificial chemicalsWaste products and artificial chemicals
used in farms, industries, andused in farms, industries, and
householdshouseholds
Each year, millions of people die fromEach year, millions of people die from
pollutionpollution

17. We face challenges in climateWe face challenges in climate
• Scientists have firmly concluded that humansScientists have firmly concluded that humans
are changing the composition of theare changing the composition of the
atmosphereatmosphere
• The Earth’s surface is warmingThe Earth’s surface is warming
• Melting glaciersMelting glaciers
• Rising sea levelsRising sea levels
• Impacted wildlife and cropsImpacted wildlife and crops
• Increasingly destructive weatherIncreasingly destructive weather
Since the Industrial Revolution, atmospheric carbon dioxideSince the Industrial Revolution, atmospheric carbon dioxide
concentrations have risen by 37%, to the highest level inconcentrations have risen by 37%, to the highest level in
650,000 years650,000 years

18. We face challenges in biodiversityWe face challenges in biodiversity
• Human actions have driven many speciesHuman actions have driven many species
extinct, and biodiversity is decliningextinct, and biodiversity is declining
dramaticallydramatically
Biodiversity loss may be our biggest environmental
problem; once a species is extinct, it is gone forever

19. Our energy choices will affect our futureOur energy choices will affect our future
• The lives we live today are dueThe lives we live today are due
to fossil fuelsto fossil fuels
• MachinesMachines
• ChemicalsChemicals
• TransportationTransportation
• ProductsProducts
• Fossil fuels are a one-time bonanza;Fossil fuels are a one-time bonanza;
supplies will certainly declinesupplies will certainly decline
We have used up ½ of the world’s oilWe have used up ½ of the world’s oil
supplies; how will we handle this imminentsupplies; how will we handle this imminent
fossil fuel shortage?fossil fuel shortage?

20. Sustainable solutions existSustainable solutions exist
• We must develop solutions that protect both ourWe must develop solutions that protect both our
quality of life and the environmentquality of life and the environment
• Organic agricultureOrganic agriculture
• TechnologyTechnology
• Reduces pollutionReduces pollution
• BiodiversityBiodiversity
• Protect speciesProtect species
• Waste disposalWaste disposal
• RecyclingRecycling
• Alternative fuelsAlternative fuels

21. Are things getting better or worse?Are things getting better or worse?
• Many people think environmentalMany people think environmental
conditions are betterconditions are better ((Human ingenuity willHuman ingenuity will
solve any problem)solve any problem)
• Some think things are much worse in theSome think things are much worse in the
world (predict doom and disaster)world (predict doom and disaster)
• How can you decide who is correct?How can you decide who is correct?
• Are the impacts limited to humans, or are otherAre the impacts limited to humans, or are other
organisms or systems involved?organisms or systems involved?
• Are the proponents thinking in the long or short term?Are the proponents thinking in the long or short term?
• Are they considering all costs and benefits?Are they considering all costs and benefits?

22. Sustainability: a goal for the futureSustainability: a goal for the future
• How can humans live within theHow can humans live within the
planet’s means?planet’s means?
• SustainabilitySustainability
• Leaves future generations with aLeaves future generations with a
rich and full Earthrich and full Earth
• Conserves the Earth’s naturalConserves the Earth’s natural
resourcesresources
• Maintains fully functioningMaintains fully functioning
ecological systemsecological systems
• Sustainable developmentSustainable development:: thethe
use of resources to satisfy currentuse of resources to satisfy current
needs without compromising futureneeds without compromising future
availability of resourcesavailability of resources

23. Will we develop in a sustainable way?Will we develop in a sustainable way?
• TheThe triple bottom linetriple bottom line::
sustainable solutions thatsustainable solutions that
meetmeet
• Environmental goalsEnvironmental goals
• Economic goalsEconomic goals
• Social goalsSocial goals
• Requires that humans applyRequires that humans apply
knowledge from theknowledge from the
sciences tosciences to
• Limit environmental impactsLimit environmental impacts
• Maintain functioning ecologicalMaintain functioning ecological
systemssystems

24. ConclusionConclusion
• Environmental science helps us understand ourEnvironmental science helps us understand our
relationship with the environment and informs ourrelationship with the environment and informs our
attempts to solve and prevent problems.attempts to solve and prevent problems.
• Solving environmental problems can move usSolving environmental problems can move us
towards health, longevity, peace and prosperitytowards health, longevity, peace and prosperity
• Environmental science can help us find balancedEnvironmental science can help us find balanced
solutions to environmental problemssolutions to environmental problems