Hey everybody, welcome to your very first
lecture in environmental science. There's
a lot of stuff that we're gonna cover in
this class. I think it's best we just go
ahead and jump right in and started going
through a little slideshow. This
shouldn't take us too long, but I think
you're getting a lot of information out
of it. So, like I said, let's just jump
right on in. In order to really kind of
dig into environmental science you
really have to understand the scale of
things, what the earth is and how it all
comes together. So we're gonna actually
start from kind of a large view of what
the earth is, its size, you know the earth
of course is enormous, or at least it seems
like it's enormous. But it and it's
systems are finite and definitely
limited and as a consequence we can
change the earth and alter its systems.
If you put enough force into something
that it's relatively small...the earth, the
earth is large relative to human beings
but it's actually really small compared
to the cosmos in the environment in
which the earth is...it's a single planet...
and we do have the ability to affect its
systems whether it's through hunting or
whether we're just dumping trash into
the oceans...or whatever it is that we're
doing...we have the ability to affect the
systems on the earth.
Okay. In terms of the environment, that's
a term we hear a lot, the environment is
all living and nonliving things around
us. This includes animals, plants, the forests, farms.  Can include continents, oceans
and clouds, ice caps...in fact that's what
we see here in this picture. This is
Antarctica down here. This white part
over here, these are the clouds, this
white down here, of course, being the ice
caps. This is Africa located right here.
The island of Madagascar, the Indian
Ocean here, the Atlantic Ocean over here.
So that's all part of the environment.
It also includes structures, urban
centers, and living centers
which include the very building or the
outside area where you might be sitting
right now watching this video. It also
includes the social relationships and
institutions. This includes governmental
institutions, corporations and the way
that people interact, say through markets
So it all comes together that's what we
mean by the environment. It's everything
coming together: the earth, the atmosphere, the biosphere and
human behavior interacting with all of
those things. Now the environment, not
only does it surround us, but it's
important to us because humans depend
upon a healthy functioning planet.
Without a healthy functioning planet we
don't get what we call ecosystem
services. We'll be talking about this a
little bit later on. Ecosystem services
that keep us alive and sustain us. Human
beings are not capable of producing
their own food, they have to derive their
food from other sources. Right, we can't
go out and photosynthesize for example
to produce food. We have to get it from
from the ecosystem. So the fundamental
insight of environmental science is we
are part of the natural world but we can
also change it. In our interactions with
its other parts matter a
great deal. In fact it's our imprint on
those other parts if we stress them too
much we could break them, and if we break
those relationships we can lose those
relationships. So again we depend
completely on the environment for
survival. We need it for increased
health, we use it for longer lives, wealth,
mobility, leisure of course, but natural
systems have been degraded by pollution,
soil erosion, species extinction, and the
list goes on and on. In fact we're going
to cover a lot of these things later on
in the course. And environmental change
definitely threatens the long-term
health and survival of portions of these
ecosystems, which could affect eventually
affect us. We ultimately rely on
something called natural resources. Now
natural resources are the substances of
energy sources needed for survival. They
come in different forms sometimes
they're really obvious to us. For example,
a natural resource that is really
important to us is something like fruit.
Right, these are things we can get off
trees that gives us the energy source
that we need for survival. Of course, fruit
gets its energy from the photosynthesis carried out by
the tree that produces that fruit. So the
fact that we can get..say apples...off of
an apple tree every year and use that
energy internally makes it a renewable
resource, OK. Because we can do it every
single year and the tree just does it
automatically. So a renewable natural
resources
is something that can be replenished.
It's perpetually renewed and ultimately
that energy is coming from sunlight, wind,
or wave energy. And, in fact, wind and wave
energy are also derived largely from
sunlight as well. We've may perhaps,
later on in the lecture series, get into
how that happens. I'm debating on how I'm
gonna take this course. But sunlight is a
big deal, and of course that's what the
tree is doing is it's taking sunlight,
taking that energy and transferring it to
the apple, which is then transferred to
us. Or, renew themselves over short
periods of time. Timber, water, and soil all can renew
themselves over relatively short periods
of times. But if you do it in such a way
that you stress it so strongly you can
ultimately destroy these resources. You
can in fact destroy the soil so it is
no longer productive. You can in fact
destroy a forest so it is no longer
going to return back in that original
form and give us those same services
that gave us before.
in contrast are non-renewable natural
resources. These are the things that are
available...that are unavailable...after
depletion. This includes oil, coal,
minerals, landscape, if you if you stress
it too much you'll lose it. Things like
this. And so here's an example of a
non-renewable resource. This is a coal
mine...this is actually a very, very, very,
large piece of heavy equipment operating
in a large open pit coal mine in Wyoming
in the United States. Alright so I
mentioned the words "ecosystem services"
before. Here it is again. Ecosystem
services: natural resources are goods
produced by nature. Earth's natural
resources provide services to us and so
those services, or those ecosystem
services are services that arise from
the normal functioning of natural
services. They purify the air, the water,
they cycle nutrients, they regulate
climate. We haven't talked about the
processes yet...we're gonna get into that
little little bit later on how the air
is actually purified, how the water is
purified, how nutrients are circulated
throughout the geosphere, in fact, as
well as through soils and things like
this. But they also pollinate plants.
We're going to get into what pollination
is a little bit later on. Pollination is
a really really important part of the of
the ecosystem it's an ecosystem service
that is extremely crucial. Not just
humans but to all of the other plants
around us. And they receive and recycle
wastes. Now we degrade ecosystem
services by depleting the resources and
by destroying their habitats and
generating pollution. So this is an
example of pollinating honeybee. If you
look at it very closely in this image,
there's little bits of pollen are stuck
to this bee, and when this bee goes from
flower to flower it's gonna transfer
that pollen to other flowers; and in
return the flower rewards the bee with
something called nectar which is then
used to create honey back at the hive.
Now in terms of how the population is
interacting with this system, it's kind
of important to know what do we mean by
the population. Well as of the time of
the recording of this video...in early April 2020...there are over seven
billion humans, almost eight billion at
this time, a large amount of that was
brought about by something called the
Agricultural Revolution. We have pretty
stable food supplies right now. This has
not always been the case in human
history. Human history has been
punctuated by times of famine and want
and need and war and pestilence, and the
pestilence isn't always on us, sometimes
it's on a crop. The potato famine in Ireland, for example, is a classic
example of this. Ultimately a lot of this
is derived from something called the
Industrial Revolution which took place
in the period of time after the 1700s.
With the 1700's on. Urbanized society powered by fossil fuels oil, gas, and coal...
and actually the early form there was
even whales that they used to hunt
they used to use whale oil to be able to power this urbanized society. We improved
sanitation and medicines, right. And of
course with better sanitation and better
medicine you're able to have a healthier
lifestyle.
And then pesticides and fertilizers were
used which made it easier to grow things
and to take care of things without pests
coming in and attacking what it is that
you're trying to produce. As a
consequence we could actually see this
is the population growth of human
beings from 10,000 BC all the way to the
year 2000 in the Common Era. That's
that's Y2K as we like to call it. And
right around there, just over seven
billion here. You can see most of this
happen just in that last sliver of time.
And its that
industrial revolution and that agricultural
revolution that's allowed that to happen.
And that number of people is still going
up. We really don't know how high it's
going to go but it's going to be quite a
large number. And so a lot of these
people are going to require these
services: sanitation, medicine, you're
going to need stable food supplies, you
know they're gonna be desiring farming,
and in addition to the comforts of
having televisions and air conditioning
and washing machines and dishwashers and things like this. So there's a lot of
stuff that's headed our way. The question
is, can the earth accommodate all of
that? How will it accommodate all of
these things? So resource consumption
exerts social and environmental
pressures. This is an interesting little
graphic that we have here.
First off, affluence increases
consumption. The more affluent you are
the more stuff you consume whether it be...
you know and some things by the way
aren't equal to other things. So for
example, if you consume a lot of celery
that's a lot different than if you
consume a lot of steak. Even if it's a
pound of each, steak is a lot more
expensive, that takes a lot more energy
and a lot more resources to produce it,
and you generally have to be more
affluent to be able to consume or to
purchase a pound of steak versus a pound
of celery. So as a consequence we see
that that tends to happen. We're going to
get into that later on. That as people get
wealthier they tend to eat more
expensive things that require more
resources to produce. So affluence
increases consumption. That results in
something called the ecological
footprint. The environmental impact of a
person or population usually is measured
in a unit of land area.
Right, so this is the area of
biologically productive land plus water.
So it's the amount of land required to
supply raw resources and dispose /recycle waste.
In other words, it's the amount of land used to keep you alive given the average consumption of human
beings in that area, right. So let's give
you an example of this over here. How
many earths do we need if the world's
population live like, let's say the
United States of America where this is
being recorded? So USA, it turns
out, if we all 7, almost 8 billion
of us live just like the way that
Americans live, it would require five
earths of resources to be able to
accommodate that. Whereas on the flip
side of that, if everybody lived just
like India does they would only require
7 tenths of one earth. And we notice that
as we go from India to Brazil to China
to Spain...as we head up this chart...these
are much more affluent countries as you
go towards the top. South Korea, Australia,
Russia is kind of an interesting case,
Germany and Switzerland are of course
very affluent countries as well as the
UK, France, Japan, so we could see this
this very interesting trend between
affluence and how many earths would be
required for everybody to live just like
everybody in that country. Currently the
world is at 1.7 earths. And so that should drive a pretty
interesting question into your mind. If
there's one earth and everybody's on it,
and we're growing in population, then how
is it we require 1.7 earths of resources
to make that happen. We're going to get
into how that happens a little bit later
on, but the concept of that of going
above and beyond your ecological
footprint is called "overshoot"...humans have surpassed the Earth's
capacity to support us by over
70%. We are using renewable resources 50%
faster than they are being replenished.
So basically we have a problem. What
we're consuming doesn't match what the
earth is providing naturally. So there's
a subsidy coming in from some location in the
ecosystem. We're gonna talk about what
that subsidy is where it's coming from a
little bit later on in another lecture.
But just be kind of be aware that we are
definitely in an overshoot situation
currently on earth. Now understanding
what environmental science is and how to
apply it can help us avoid past mistakes.
So how will resource consumption and
population growth impact today's global
society, right? We're growing, what is the
impact going to be? How is it going to
change things? How do we decide how to
allocate what resources in the
directions that we want them to go?
Civilizations have fallen after
degrading the environment. It's not...
this is not some...kind of some benign
concern. It happens. It''s happened on
smaller scales and now people are
starting to look at a more global scale.
So Easter Island, which is located in the
East Pacific off the coast of South
South America, is a classic example of
this. This is where we see what used to
be a lush forested area.
The lush forested area has been
completely decimated. But a lot of it is
believed to have been...a lot of those
resources were believed to have been
used to erect these monumental statues
that they have all over the island. The
island is famous for them. But the amount of resources it took to probably put
those in place wound up costing them
their entire forests, and their forest
ecosystem collapsed, and their
populations probably collapsed as well.
Of course, you can read a lot about
Easter Island, it's a very famous case. So
this one very lush island, Easter Island for example,
is now barren. But it's happened in other
places too.  It happened to the Greek and Roman
empires. Some people have said that it
happened at Carthage as well. So there's
a lot of information that suggests that
understanding environmental science can
help us avoid some type of very negative
fate that we can't see coming. In fact,
when I'm recording this right now, the
COVID-19 virus is currently moving across the
planet. It's possible that it will be
solved in a very short period of time or
it could persist for a very long period
of time. But understanding environmental
science lets us know that, you know when we're
dealing with something like this, it's
probably best to stay indoors and stay
safe and stay away from these things.
That's science telling
us, from experience, what might work for
the future. We're going to get into how
science works here briefly in a couple
of slides. So civilizations succeed or
fail according to how they interact with
the environment along with how they
respond to problems. So in this situation,
they cut down all the trees, they weren't
able to recover it, and the
civilization essentially collapsed. So
environmental science can help build a
better world. That's the hope, that's what
we're hoping will happen going forward.
Now how do we go about solving these
problems? How do we...one of the
biggest issues we have is how these
problems are perceived and how our
responses are perceived.
So sometimes it's cultural. So whether an
environmental condition is seen as a
problem depends on the individual and
the situation. Right, so a classic example
this is DDT. DDT is a compound that
was used to deal with malaria
infestations across the world. In Africa,
it is welcome because it kills malaria by
killing mosquitoes but in America does
not welcome due to the health risks. So
DDT is considered a very toxic thing to
put on your kids, but in Africa the fear
is greater that you're going to be
affected by something that's gonna give
you malaria. Alright. It's a cultural
perception that we see here. What we see
here in the image is this is an Italian
soldier in Italy spraying a mixture of DDT and
kerosene to control malaria and this is
in war-torn Italy in 1945. And you can
see that child was not terribly happy
with this development. Question is would
you be okay with DDT being sprayed on you or your children? if you lived in the
United States it would probably be
perceived as a very bad thing. If you
lived in Africa probably wouldn't be
considered such a big deal.
Now...I want to make sure that as we go
forward that we understand that there's
a difference between what environmental
science is and what it isn't. And one of
the things that is constantly conflated
with is environmentalism. So let's talk
about what environmental science is. So
environmental science pursues knowledge
about the environment and our
interactions with it scientists try to
remain objective and free from bias. Okay.
So whatever the data says, it says. We
need to work with it. We can't massage
things. We can't change things. We need to
work with what we have. This is a little
different
different than other things that you
might see going on in the world. Another
thing you might see that's constantly
conflated with environmental sciences
environmentalism. Environmentalism is a
social movement. Sometimes it's a
political movement, but it's largely a
social movement that tries to protect
the natural world from human caused
changes. Now environmentalism is not
objective, it is not free from bias, it is
very subjective, right. People that are
usually in the environmentalism or
environmentalist movements have a very
very strong opinion about a certain way
that either society should go or a
certain way that a problem should be
dealt with. Scientists and the social
scientists, can be environmentalists, right,
and environmentalists can be scientists,
but they are actually different spheres
of thinking. As long as you understand
that one is a series of actions or it's
a it's a social movement, and the other
one is an actual objective form of
looking at the environment in the world
in which we live, then you're kind of
gonna be okay going forward. If you're
kind of confused about that kind of
stuff you're gonna get stuck on the "wait
a minute, I thought this class was about
saving the whales" or I thought this
class was about Greenpeace. It's
great to save whales. It's great to study
what goes on with Greenpeace. It's great
to study what's happening with those
things. What might be driving that
environmentalism in Greenpeace or in
saving whales might be environmental
science knowledge behind that. But just
be aware that those are organizations
that are
a social movement. And so you can
typically recognize a social movement...
when you see you know people marching on down the road, this is from the
people's climate March in 2014.  So that
of course leaves us with the question of
what is science. So we're not going to
get into a deep discussion what science
is just in this little lecture, but we
are going to kind of give you a very
brief introduction to the concept of
what it is. So science is a systematic
process for learning about the world and
testing our understanding of it. The
accumulated body of knowledge arising
from the dynamic processes, or process
of observation, testing, and discovery.
Civilization depends upon Science and
Technology. Just has. In order to move
forward, our interactions with each other,
our ability to observe, test, discover, and
to trade those ideas with each other is
fundamental to how society operates.
Science tries to understand the world
and steer a safe course. That's our
ultimate goal. Right. If you know, for
example...like I mentioned earlier, we have
this virus. If you know that there's a
virus that's raging across the world and
that virus has fatal impacts on certain
groups of people or even on the entire
population, it's best to steer
clear of that virus. Right. How do
we know to do that? Past experience. Right.
We've observed it, we've tested it, we've
discovered that staying away from the
virus keeps us safe. And then we don't
die of it. Has that always been kind of
common sense? No! It used to be very, very
different people used to die left and
right from these types of viruses in
human history. And our understanding of
how these things operate have informed
us on proper responses. Now science is
essential to sort fact from fiction and
develop solutions to the problems we
face. And that's just how it is. I mean
it's designed to figure out what is the
truth about a certain thing to the best
of our ability to find it. Sometimes the
truth is knowing what it isn't.
Right? We just don't know
what a solution is but we
know that these aren't solutions. Right?
So sometimes science is in the negative.
Right. This is what we know not to do if
there's ever this problem. And so that's
what science does. It must be accessible
and understandable to the public. And
that's really where you're kind of
coming into my lecture...is...I'm trying to
find a way...and I'm gonna work really
hard at it over the next series of
lectures that we put out...to make this
information accessible and
understandable. And that includes
understanding things like the vocabulary...
I'm going to emphasize the vocabulary
very strongly. You're gonna find that any
freshman level or sophomore level class
is going to emphasize the vocabulary
because without it you're gonna be lost
in any conversations or any reading that
you ever do on the topic. Okay.
In terms of the kinds of science that
we've done, you know, we have the
great pyramid, here's the sphinx out
here in the front, and of course, the
ability to construct something like this
required some previous experience. Right?
This is something that they observed, they
tested, they actually had some
engineering knowledge on, and they went out and they built the Great Pyramid. The same
thing with the Sphinx, right? The artists
that came through and carved out this
thing...and I believe it's in sandstone, I
might be wrong...but whoever did this had
a tremendous amount of experience. And so we recognize that, that this requires a
certain level of sophistication that
science brings that civilization
ultimately depends upon. And when we look at these things we recognize these as
major, as major symbols of the ancient
Egyptian civilization. Now scientists
test ideas by critically examining
evidence. Now science is an incremental
approach to the truth. In other words, we
don't usually figure out what the answer
is the very first time. Sometimes...again
there might be thousand different
options on what we're looking at there
might be a thousand different
explanations for a phenomenon...and
sometimes we just simply say "not that
one," "not that one," "not that." Right. So we
incrementally approach it, okay.
Now, the other thing is that scientists
do not simply accept conventional wisdom.
They judge ideas by the strength of
their evidence. And we will find, as we go
forward in the class, that a lot of the things
that people take for granted just simply
aren't true. And I don't want to tip my
hand on some of these conversations, but
some of the issues, such as how to carry
out proper agriculture for example, that
conventional knowledge that you might
have been raised with is just simply
wrong, and we're going to talk about that
a little bit later on.
Now observe there's two
different ways we
carry out science. There's observational
or descriptive science. This is
information gathered about
organisms, systems, processes, whatever...
and cannot be manipulated by experiments. The phenomena are observed and measured,
it's used astronomy, paleontology,
taxonomy, genomics...a great form of
this as geology. I actually have a
background in geology. Imagine something
as amazing as a volcano. A volcano is
something that you can't really
manipulate using an experiment. You can
build models of volcanoes, but never, ever
gonna get to the actual heart of what
happens in a volcano. You actually have
to go out and just simply watch these
things, using different ways. Right. You
might look at seismics, you might listen
to the sounds that come out of it, you
might be looking at the gases that come
out of the volcano. Right? But you're
gonna be observing and you're gonna be
measuring a lot of stuff. In contrast
with that is hypothesis-driven science.
This is targeted research. This is where
you're doing experiments. You're
manipulating things and you're seeing
what happens as a consequence of that
manipulation. So these are experiments,
test hypotheses using the scientific
method.  And that word hypothesis is kind of a
loaded word. We're gonna get into that
here in a moment. All right so this is
the traditional approach for the
scientific method. You've
probably have seen diagrams like this
your entire life, but we're gonna get into it
here in a moment. Now scientific method tests ideas,
scientists and different fields approach
problems differently, the way a geologist
is going to look at a problem is going
to be very different than the way a
biologist, or in some cases...if you're dealing with the social sciences...the way that they're
going to approach the problems. Okay.
So a scientist makes an observation and
ask questions about some phenomenon. This is how it always starts. Right. So there's
an observation, and then and there's a
question. For example, maybe the
observation is: there's a very large
valley in the middle of northern Arizona.
"How did it get here?" might be the
question. Okay. Then if you don't
realize what I'm talking about here, I'm talking
about the Grand Canyon. So there might be a hypothesis: statement that tries to
come to explain the question. The word
"hypothesis" is kind of one of those weird
loaded terms that you've probably heard
your whole life and people say it's an
"educated guess." I've never really liked
the words "educated guess." It's really not
a good interpretation of the word
"hypothesis." The closest word in English
is the word "conjecture." Right. So,
conjecture is a
statement of explanation that is based upon less than all
the information that might be available [or known]. Especially going forward. So that's when
we're talking about a hypothesis,
this is a conjecture. And so what you do
is you take your hypothesis and you
generate these predictions, and specific
statements can then be tested through
experimentation. So maybe as you're
looking at the Grand Canyon, you might
have several conjectures about how this
giant, beautiful, feature in northern
Arizona formed. Maybe it was formed from
maybe...as a volcano that's ripped open
the area, maybe a lava flow has covered
the area burned a giant hole down into
the bottom, maybe it's a
giant river valley that's caused when
the entire plateau in northern Arizona
uplifts. There's different ways of going
about this and looking at the
experiments. Okay, um...so we would carry
out these experimentations, we would get
results. So maybe as I go out into the
Grand Canyon I realize [that] while there are
lava flows there are very few of them
and they don't seem to really control
the location of where the valley is. In
fact, the valley seems...if anything...to
have captured some of these lava flows
and in some interesting ways. So maybe it's
not created by a volcano, right? Maybe it's not created
by a giant impact crater...maybe a giant
asteroid did not create the Grand Canyon.
But when you look down at the bottom of
the Grand Canyon you see the beautiful
Colorado River moving through it and you
think to yourself "maybe the river is
responsible for the creation of this
Canyon" and, in fact, science has told us
that it is, in fact, the cause of the
formation of the Grand Canyon. So we
could then test those predictions and
the test results either support or
reject the hypothesis. So observation to
hypothesis. Right. The hypothesis is your
conjecture. Then you do some experiments
or you do some some tests and you get
the results. If it's consistent or
supports your hypothesis you repeat it,
and if you keep getting the same thing
over and over and over again, then you
know it fits, it fits every single time
you do another test or another
experiment. Eventually that can become
your scientific theory, which will then
become the accepted view of that
phenomenon. Right, people don't accept
that the Grand Canyon is created by a
giant volcano. They accept that is
created by the Colorado River. All of our
evidence supports that hypothesis and so
that's our scientific theory. But if we
came in here and we looked and we said
we can't find the lava flows but there's
a tremendous amount of sand that's being
deposited in the Gulf of California that
seems to be from the Colorado River and
the amount of that deposition seems to
match roughly the volume of material
that's removed from the Grand Canyon, maybe we need to revise
this hypothesis, redo our experiment we
wind up in the right place. The goal is
that, given enough experiments in enough
time, we will eventually wind up with
some theory of that phenomena. All right,
so when we're carrying out science we
actually need to be aware of
some important parameters and vocabulary
so that we are able to keep track of
everything that's going on. So we're
gonna take a little bit of time, because
this is this is something that's gonna
happen a lot during the upcoming lecture.
So I'm gonna bring these concepts
up. So it's best to get them in right
away. So the first concept is something
called a variable. It's a condition that
can change. Its
anything that can change. Now an
independent variable is a type of
variable. It's a variable whose variation
does not depend on that of another. In
other words, it just simply is. It simply
is independent...it doesn't change. It's
not dependent upon something else.
Whereas a dependent variable is a
variable that depends on the independent
variable. So for example, maybe the amount
of water that is given to a plant
might be an independent variable. It's a
variation that does not depend upon
another. It just simply is that value. So,
for example, here we have a bunch of
plants that are in a lot of little pots
here...these are what they call "Hawaii
silver swords"...they have identical
planting and it makes them an ideal for
a controlled experiment. So we can do
everything exactly the same, that gives
us a good independent variable. Now the
dependent variable is something that's
going to be dependent upon the
independent variable. So for example
maybe this particular plant has a slight
difference in genetic structure...er....in genetics. So it might have a
different outcome
but you water them all exactly the same.
Right. So a controlled experiment is one
in which the effects of all variables
are closely controlled. It's designed to
minimize the effects of variables other
than the independent variable. In other
words, if you want to see an effect you
want to make sure everything is exactly
the same to the best of your ability so
that you can measure an actual response
to what you're doing. So a control is an
unmanipulated point of comparison. So, as
long as everything is the same and you
do everything the same you only thing
you're changing is the one thing, the
control is shows you what the outcome
would have been had you not made that
change.  There's two ways that this is
usually reported. You have quantitative
data this is something that uses numbers,
right. You get an actual numerical output.
For example, maybe you're measuring the
height of plants. Or qualitative data
that does not use numbers. Maybe it's a
color for example. Even in color you can
even use certain numbers by looking at
wavelengths and things like this. But you
know qualitative is another way of doing
it. A lot of chefs that are doing cooking
they do a lot of qualitative data.
Quantitative data when you're doing
cooking school, for example, is a little bit
more challenging. Alright, so we tend to
test hypotheses in different ways. We
kind of hit on this a little bit earlier.
But you can do a manipulation...this is
where you control the independent
variables...and when you control of
independent variables you can reveal the
causal relationship. You
know, if I hit a...I don't know...hit a
watermelon with a bullet, the watermelon
is gonna break. But if I hit a watermelon
with a sponge it's not. That kind of thing. And so I can actually
put together these very simple causal
relationships. In medicine, this is of
course a very big deal. Many things
however cannot be manipulated, so that's
when we usually do natural experiments. A
classic example of something cannot be
manipulated easily...sometimes not at all...something like a volcano. This is a
volcano in Costa Rica at night time. You
can see the lava flows flowing down from
the summit. You wouldn't want to get near
this thing, it would probably kill you if
you tried. So in this case you use
existing conditions to test the
predictions, little control over the
variables, and the results are not neat
and clean. You know, sometimes you'll, you'll look at
something like a volcano like this and
you can't get exactly the data you want
but you can get a kind of an estimate on
what it might be doing. Maybe it's the
type of lava that's coming out, the kinds
of gases that are coming out,
temperatures, there's ways to get good
measurements on these things. But there's
always, sometimes some information that's not as clean as we want it to be. So,
science tends to go through these things
called paradigm shifts. These are large
changes that happen. And so we start off
these theories...we talked about these
earlier, right...it so it's a well tested
and widely accepted explanation of
something, of a phenomenon that's
happening, and it consolidates widely
supported, related, hypotheses. In other
words it's something that brings
everything together. And it makes
everything understandable, until
something undermines that...completely changes it. And when that changes
that's called a paradigm shift. It's a
dramatic upheaval of thought that
changes the dominant viewpoint. The
classic example of a paradigm shift
happened in geology for example...where they
discovered that continents on the
surface of the earth actually move
around, as well as ocean basins, tend to
evolve over very long periods of time.
Prior to that there was no concept of
this. It didn't seem like the continents
could move around on the surface of the
earth and everything was explained using
a completely different system. We now
know that that old system isn't accurate
and it was done away with and it was
replaced by the current plate tectonic
system. Similar things have happened in
biology. The understanding that genetic
information is transferred through DNA
and RNA as opposed through other means
was a huge eye-opener for many people
studying the biological sciences. Now
some problems are what we call "wicked
problems." These are extremely complex
problems that don't have any simple
solution. In fact, there might not even
appear to be as a single solution to any
of it. And environmental problems are
classic examples of wicked problems. You
know, here we see this is a trash covered
landscape in Jakarta, Indonesia. The boys
out here scavenging for usable and
edible materials, the dogs are out here
eating whatever they could they can find.
And in a weird way, them being out there
doing this helps clean the landscape but
in another way it also encourages more
poverty and this is obviously not the
way you want to live, right. So wicked
problems happens whether the economic
problems, political problems...and in case of an environmental problem, who's
responsible for this clean up? Right. How
did the trash get here in the first
place. This is a public policy problem?
It's a cultural problem? I don't know.
Right, it depends upon how we go about
solving or looking and analyzing these
these issues. And, in fact for these dogs,
it's not a problem at all, right, because they
actually have a free meal. All right so
let's start introducing another word
that you hear a lot when it comes to
environmental science it's called
"sustainability." Sustainability is a
concept that a lot of people
misunderstand. They usually think that it
means..."sustainable" means "conservation." It
can mean conservation. It's one of the
things that we frequently see but it's
not the only thing that we see when we
talk about sustainability. So
sustainability is the idea that we must
within our planet's means so the earth
and its resources could sustain us and
all life for the future. So basically
it's what can we do to make sure that
the ecosystems continue to provide what
we need so we can continue on the path
that we currently are on. If we don't
change things...obviously we're at 1.7
earths of resources, that's not
sustainable, the earth could only sustain
one...so something's going to break or
something's going to give at some point.
So sustainability involves conserving
resources, developing long-term solutions,
and keeping fully-functioning ecosystems.
And that results into this concept of
natural capital. What is it that we're
deriving our existence from? Well,
it's Earth's total both of resources.
That natural capital. And we are
withdrawing it faster than its being
replenished. We must live off of Earth's
natural "interest" which is the
replenishable resources, not its
natural capital. So the natural capital
is what the actual earth is. The actual
ecosystems, what they're actually putting
out, right. Whether it be the sum of fish
or whether it's the forestry services or
whether it's the air services or the
replenishment of the nutrients and the
soils. If we're pulling it out faster
than it can go in, then we're actually...it's like having a checking
account, or I'm sorry, a savings account
and instead of spending just the
interest that you generate every single
month, you're also spending the
actual principal that you put in.
eventually once you've drawn the
principal you don't have either. You
don't have you don't have the interest
income and you don't have the principal.
That's the same concept here of natural
interest. It's Earth's replenishable
resources. Something you get every single
time without having to do anything.
Classic example of this natural interest
that they're talking about are these are
salmon in the wilderness of southern
Alaska. They come back every single year and you can harvest approximately 50% of
them every single year sustainably...forever...but if you take more than that
you will impact this. And of course if
you impact this the rivers...maybe you take the
water away or you put a mine in the area
and the mine pollutes that river...then you
lose the salmon that way as well so this
is the natural interest that they're
talking about the fact that we could
draw on that salmon every single year as
a resource without diminishing it,
as long as we're careful. Now population
consumption definitely drive the impact.
As we get larger we have larger impact
so population growth amplifies all human
impacts. The growth rate has slowed but
we still add more than...20 or 22 or...220,000 people...wow, I understanded it by
mistake...220,000 people to the planet
each day. That's a number I looked up
right before recording this lecture.
So resource consumption has risen faster
than population because people are
becoming more affluent, right. Life has
become more pleasant. So, as those people come on line and join the rest of us in
the economy, they're also wanting to live
better lifestyles. They want air
conditioning, they want farms, they want
to have a nice school, they want good
libraries. And this isn't just in the
United States, this isn't just in North
America, this is worldwide that this is
happening. And eventually they're going
to want these things everywhere and get
those things everywhere. But that
requires resources. So, rising consumption
also amplifies our demands on the
environment, which is one of the reasons
why we're seeing so much environmental
degradation happening at exactly the
same time. So here we see kind of this
classic family over here. But think about
the amount of resources it takes to
clothe them, to put this tablecloth on
here, to make the pottery, to produce the
food, that goes into just a single meal,
right. Just to make that image exist with
all of its attributes. And you can see
they're all happy and they're taking a
great family photo together but the
issue is still the same. It requires a
tremendous amount of resources for the
earth to be able to produce just that
single event to have it happen. So the
ecological footprints of countries vary
greatly...as we talked earlier the United
States footprint is much greater than
the world's average. This is a typical
American family today as we know it. So
what are some of these impacts? What
causes some of these impacts?
Well, erosion and other impacts from
agriculture drive impacts. Deforestation,
right our desire to cut down trees for...not only just for the lumber but
also because we want the space...trees tend to grow in very favorable areas
especially in flat lands. Toxic
substances are becoming a major issue.
Fresh water depletion. Whenever...in fact I say it all the time and I'll
say it many times during this class...fresh water is worth much more than gold.
So the desire to go and get access to
fresh water is huge.
Fisheries declines. Air and water pollution.
Waste pollution. Mineral extraction and
mining impacts. Global climate change and
of course loss of Earth's biodiversity.
And we're going to talk about that a lot.
That's a really, really big deal. Now, once
a species is gone...it is gone, or have
gone extinct...it is gone forever.
So biodiversity is a big deal. And you
might not think of it as a big deal like,
you know...for example what who cares if a
toad goes extinct? Aren't there other
toads? Well maybe not the kind of toads
that we need them to be. All right. So
this is the golden toad.  This is an
animal that's been completely absent
from human eyes since 1989, is considered to be extinct. So this is a picture from
before 1989. In terms of things that we
do on a day-by-day basis, it's usually
our energy choices that tend to have the
largest single influence on a day-by-day
basis. So the lives we live today are due
to fossil fuels. Everything all the
conveniences that we have. The machines
that we have. In fact, in order to produce
steel you need to take fossil fuels...not
only to heat the iron...but you actually
take part of the fossil fuels and you
use it to alloy itself with the iron to
make steel.  Chemicals: a lot of the
fertilizers that you guys use on your
plants actually come from petroleum.
Transportation of course comes from
petroleum. Consumer products: a lot of the
makeups that people like to wear on
their face, a lot of the clothing that
they like to wear, also come from
non-renewable resources and things like
petroleum. And fossil fuels, of course, are
one-time bonanza because once we burn through all that stuff and used it all,
it's going to decline. And we've had
moments in time where it looked like
that was happening. There in the early
2000s, it definitely looked like we were
going to be reducing the amount of oil...especially in the United States. It
actually took a technological change to
be able to increase
American oil to be able to bring down
the price, but it looked like the price
is going to go up and up and up and
never stop. So it's possible that we'll
get back to the point where we...the
technology is no longer efficient
anymore to extract oil and the price
will go back up again. Here's a current,
or I shouldn't say current, but it's a 2011
world energy consumption chart, and here
we can see oil is the largest one.
Natural gas, which is another by-product
from the production of oil...largely from
the production of oil...is about 1/4. 30%
is coal, this is another fossil fuel. 4.9%
is nuclear energy. Now that's wonderful
if you are somebody that is really
worried about greenhouse gases. It
turns out nuclear energy does not
release any greenhouse gases but it has
other byproducts that are extremely
dangerous that are part of the
environment that we have to be concerned
about. And also nuclear power doesn't
power your car. So you have to use either
oil, natural gas, or some other fossil
fuel, or electricity maybe it's not maybe
Drive a Tesla or something like this and
then there's renewables. All right, so
that's the end of our little
introduction. Next lecture is going to be on
matter and energy and environmental
systems and how they all come together.
So this was intended just to be a quick
introduction. So what we're gonna do is
give you a little break, we're gonna come
back in the next lecture and we're gonna
dig right into matter and energy. All
right. Take care!
