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0:00
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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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.
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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
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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
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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
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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
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something called nectar which is then used to create honey back at the hive.
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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
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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...
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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
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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.
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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
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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
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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
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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.
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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
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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
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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
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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
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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
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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.
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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.
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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,
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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
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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
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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
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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
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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.
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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
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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
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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,
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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.
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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
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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
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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
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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
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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
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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,
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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
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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
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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
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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.
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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.
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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,
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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.
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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
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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
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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
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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
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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
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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
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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
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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!
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