Environmental Systems

Summary

This Environmental Science video delves into the concept of environmental systems, emphasizing the importance of understanding inputs and outputs for effective management. It highlights the Aral Sea's transformation into a desert due to inefficient irrigation, illustrating the consequences of poor system management. The video explains the closed nature of matter on Earth and the open system of energy, introducing the laws of thermodynamics and their impact on resource availability and energy conversion. It also touches on the significance of atoms, their organization in the periodic table, and their role in forming stable molecules. The script concludes by discussing systems analysis, steady states, and the role of feedback loops in maintaining balance in natural systems.

Takeaways

• 🌍 Understanding systems is crucial for addressing environmental challenges, such as the transformation of the Aral Sea into a desert due to inefficient irrigation practices.
• 💧 The Earth is a system with inputs and outputs, and managing these effectively is key to environmental sustainability.
• 🔄 Matter on Earth is conserved; it is a closed system, meaning we cannot create or destroy matter, only transform it.
• ☀️ Energy, on the other hand, is an open system where we receive energy from the sun and lose it as heat, highlighting the importance of energy conservation and efficiency.
• 🔬 Systems analysis is essential for maintaining steady states or equilibrium in environmental systems, using feedback loops to regulate inputs and outputs.
• 🔄 The first law of thermodynamics states that energy cannot be created or destroyed, only converted from one form to another.
• 🔄 The second law of thermodynamics emphasizes the loss of useful energy during conversion, leading to an increase in entropy and the generation of heat.
• 🌿 The periodic table organizes the finite atoms on Earth, with elements like carbon being fundamental to building complex molecules through covalent bonds.
• 🧬 Humans, like all living organisms, are composed primarily of water, with oxygen being the most abundant element by mass.
• 🌊 Water's polarity affects its behavior, which is important in environmental systems, including understanding pH and the role of buffers.
• 🌡 The study of energy and its quantification, such as in the work of James Joule, is fundamental to understanding the capacity to do work and the flow of energy in systems.

Q & A

What is the main topic of the Environmental Science video 2?

The main topic of the video is understanding environmental systems, including what a system is, how it works, and how to manage inputs and outputs to tackle environmental problems.

Why is the Aral Sea a good example to discuss in the context of environmental systems?

The Aral Sea serves as a good example because it used to be the fourth largest lake on the planet but became a desert due to inefficient irrigation practices, illustrating the consequences of poor system management.

What were the consequences of the Soviet Union's irrigation practices on the Aral Sea?

The consequences included the death of fish, the collapse of the fishing industry, and an economic downturn, all resulting from the mismanagement of the water resources and the system's inputs and outputs.

How does the Earth's system differ from the system of matter and energy in terms of being open or closed?

The Earth's system of matter is a closed system with a finite amount of atoms that are conserved over time. In contrast, the system of energy is open, receiving energy from the sun and losing it as heat.

What are the two main components of a system that we need to focus on according to the video?

The two main components to focus on are matter and energy. Matter is what everything is made of, while energy is the ability to do work.

What is the significance of the conservation of matter on our planet?

The conservation of matter means that the amount of matter on our planet is finite and does not increase or decrease over time. This has implications for resource management, as we cannot create new minerals or elements.

What is the first law of thermodynamics, and how does it relate to energy?

The first law of thermodynamics, also known as the law of conservation of energy, states that energy cannot be created or destroyed, only converted from one form to another.

What does the second law of thermodynamics tell us about energy conversion?

The second law of thermodynamics indicates that with every energy conversion, some of the useful energy is lost as heat, which is not usable for further work on our planet.

How does systems analysis help in understanding the state of a system?

Systems analysis helps by examining the inputs and outputs of a system to determine if it is at a steady state or equilibrium. It also helps in identifying feedback loops that can either maintain or disrupt this steady state.

What is a negative feedback loop, and how does it help maintain a steady state in a system?

A negative feedback loop is a process within a system that corrects changes and helps maintain a steady state by counteracting deviations. For example, as a lake's water level rises, increased evaporation and drainage work to lower it back to the steady state.

What role do positive feedback loops play in the Earth's climate system?

Positive feedback loops in the Earth's climate system amplify changes rather than counteract them. For instance, increased evaporation due to warming can lead to more greenhouse gases, which in turn causes further warming.

Why is the understanding of atoms and their organization on the periodic table important in environmental science?

Understanding atoms and their organization on the periodic table is crucial because it helps us comprehend the composition of various environmental components, such as humans, water, rocks, and the atmosphere, and how they interact within the Earth's system.

What is the significance of oxygen in the composition of living organisms, water, and rocks?

Oxygen is significant because it is the most abundant element in living organisms, water (H2O), and many rocks, such as silicates. It plays a central role in biological processes, the water cycle, and geological formations.

How does the concept of a steady state relate to the management of environmental systems?

A steady state in environmental systems indicates a balance between inputs and outputs, which is essential for sustainability. Managing a system towards a steady state helps maintain ecological balance and prevent degradation or depletion of resources.

Outlines

00:00

🌿 Environmental Systems and Their Management

This paragraph introduces the concept of environmental systems, emphasizing the importance of understanding systems to address complex environmental issues. The Aral Sea's transformation into a desert due to inefficient irrigation practices by the Soviet Union serves as a case study. It highlights the necessity of managing inputs and outputs within a system. The Earth is described as a system with finite matter and a continuous flow of energy from the sun, introducing the principles of conservation of matter and energy, as well as the laws of thermodynamics. Systems analysis is presented as a tool for understanding system dynamics, including steady states and feedback loops.

05:01

🔥 Energy Quantification and Thermodynamics

The second paragraph delves into the quantification of energy, crediting James Joule for establishing the measurement of energy in joules. It explains the concept of watts as joules per second, illustrating the relationship between energy, work, and time. The laws of thermodynamics are discussed, focusing on the conservation of energy and the inevitable loss of usable energy at each stage of conversion, leading to heat. Systems analysis is applied to the Earth's climate, using the metaphor of a bathtub with holes to explain steady states and the role of feedback loops in maintaining them. The paragraph concludes with examples of both negative and positive feedback loops in the Earth's climate system, such as the melting of ice and the effect of water vapor as a greenhouse gas.

Keywords

💡Environmental Systems

Environmental systems refer to the complex networks of interactions between the biotic and abiotic components of the environment. In the video, understanding these systems is crucial for addressing environmental challenges like the Aral Sea crisis, where poor irrigation practices led to the lake's near disappearance. The concept is central to the video's theme of managing and analyzing environmental issues.

💡Aral Sea

The Aral Sea, once the fourth largest lake on Earth, is used in the script as a case study to illustrate the devastating effects of unsustainable environmental practices. The Soviet Union's inefficient irrigation for cotton and rice cultivation led to the lake's desiccation, turning it into a desert and causing an ecological and economic disaster.

💡Irrigation

Irrigation is the artificial application of water to land or soil to assist in the growth of crops. In the context of the Aral Sea, inefficient irrigation practices contributed to the lake's decline by diverting water away from its natural replenishment cycle, highlighting the importance of sustainable water management in environmental systems.

💡Economic Collapse

Economic collapse refers to a severe contraction in an area's economy, often due to external shocks or systemic failures. In the script, the drying up of the Aral Sea led to the death of the fishing industry, causing an economic collapse in the region, underscoring the interdependence of environmental health and economic stability.

💡Inputs and Outputs

In environmental systems, inputs are the resources or energy that enter the system, while outputs are what is expelled or used. The video emphasizes the importance of managing these to maintain a system's balance, as seen in the Aral Sea example where poor management led to environmental degradation.

💡Matter

Matter is anything that has mass and occupies space, and it is a fundamental concept in the video. The Earth's matter is described as a closed system where the total amount is conserved, meaning it is neither created nor destroyed. This concept is crucial for understanding resource management and the finite nature of materials on our planet.

💡Energy

Energy, in the context of the video, is the capacity to do work and is presented as an open system where energy is continuously received from the sun and lost as heat. Understanding energy flow is vital for analyzing environmental systems, as it drives processes like photosynthesis and climate change.

💡Thermodynamics

Thermodynamics is the study of the relationships between heat and other forms of energy and work. The video discusses the first and second laws of thermodynamics, emphasizing the conservation of energy and the decrease of usable energy in systems, which is critical for understanding energy transformations and efficiencies.

💡Feedback Loops

Feedback loops are processes within a system that regulate its behavior by providing information about the system's output back to its input. The video explains both negative and positive feedback loops, illustrating how they maintain steady states or exacerbate changes in environmental systems, respectively.

💡Steady State

A steady state in environmental systems is a condition where the inputs and outputs are balanced, and the system remains stable over time. The video uses the analogy of a bathtub with holes to explain this concept and discusses how feedback loops help maintain or disrupt steady states in various environmental contexts.

💡Atoms

Atoms are the basic units of matter, consisting of protons, neutrons, and electrons. The script explains that the Earth's matter is made up of a finite number of atoms, which are organized in the periodic table and are the building blocks of all substances, including those in the environment and living organisms.

💡Polar Molecules

Polar molecules, like water, have an uneven distribution of electron charge, leading to a molecule with distinct positive and negative ends. The script mentions the importance of understanding water's polarity, which affects its behavior in the environment, such as its high boiling point and its role in biochemical processes.

💡pH and Buffers

pH is a measure of the acidity or alkalinity of a solution, while buffers are systems that resist changes in pH. The video script suggests that understanding pH and buffers is important in environmental science, as they influence chemical reactions and the health of ecosystems, such as maintaining the balance in natural waters.

💡Biological Molecules

Biological molecules are the large organic compounds that are essential to life, including proteins, carbohydrates, lipids, and nucleic acids. The script implies that understanding these molecules is crucial for studying life processes within environmental systems and their interactions with the environment.

Highlights

Understanding environmental systems is crucial for tackling major environmental problems.

The Aral Sea example illustrates the consequences of poor environmental system management.

The Earth is a system with inputs and outputs that need to be managed for sustainability.

Matter on Earth is conserved, making it a closed system with finite resources.

Energy on Earth is an open system, receiving energy from the sun and losing it as heat.

The conservation of matter has significant implications for resource management.

The first law of thermodynamics states that energy cannot be created nor destroyed.

The second law of thermodynamics addresses the loss of useful energy during conversion.

Systems analysis involves understanding the balance of inputs and outputs to maintain steady states.

Negative feedback loops help maintain steady states in systems, such as lake levels.

Positive feedback loops can destabilize systems, as seen in global warming scenarios.

The periodic table organizes atoms, which differ in reactivity based on their electron configuration.

Carbon's unique electron configuration allows it to form complex molecules, essential for life.

The human body's composition is predominantly oxygen and hydrogen, due to water content.

Seawater's composition is similar to the human body, with oxygen and hydrogen being the majority.

Rocks are primarily composed of oxygen, with significant amounts of silicon, aluminum, and iron.

The atmosphere is mostly nitrogen and oxygen, with trace elements playing various roles.

Water's polar nature affects its behavior and is fundamental to understanding environmental systems.

pH and buffers are crucial concepts for understanding environmental chemistry.

Biological molecules, built from atoms, are the basis of life and are integral to environmental systems.

James Joule's experiments quantified energy, leading to the unit of energy measurement, the joule.

Transcripts

Hi. It’s Mr. Andersen and this Environmental Science video 2. It is on environmental systems.

Understanding what a system is and how it works can allow us to tackle really hard,

some of the worst environmental problems that we have ever had. A good example would be

the Aral Sea. And so it sits on the border of Kazakhstan and Uzbekistan. And it used

to be the fourth largest lake on the planet. And so the Soviet Union was irrigating off

the Aral Sea to grow cotton and rice. And it was not super efficient irrigation. And

so if you watch what happened to the Aral Sea from 1989 until to 2014, it essentially

became a desert. And so we just see the South Aral Sea on the western margin. So the fish

all died. The fishing died. And so we had economic collapse. And this was a problem

with the system. We were not managing the inputs and the outputs. So the earth at the

largest level is a system. It is separated from its surroundings. And understanding the

inputs and the outputs allows us to manage a system. And so the big things we are looking

at are the matter and then the energy. The matter remember is what we are made of. It

is the atoms that make us and the rock and the water. And the energy is the ability to

do work. Now if we look at the matter on our planet, it is actually a closed system. The

amount of matter we have on our planet is conserved. We do not get new matter from space

so we are stuck with the atoms that we have. It is conserved over time. If we look at the

energy however, it is more of an open system. We continue to get energy coming from the

sun and we lose that energy as heat. And so the thing about matter you should understand

is that it is conserved. And this has huge ramifications. If we are looking, for example,

for minerals. You can not just grow minerals. The amount of minerals we have on our planet

are finite and we have to go find those minerals. If we are looking at energy, understanding

the laws of thermodynamics. The first law is essentially the conservation of energy.

Energy can neither be created nor destroyed. But the second law is also important. And

that deals with the amount of useful energy. Every time we have an interaction when we

are converting energy, we are losing some of that useful energy. And so understanding

how a system works is done through systems analysis. If it does not change we say that

system is at steady state or at equilibrium. And we can move it towards steady state using

a negative feedback loop or away using a positive feedback loop. So big picture, a system is

simply separated from its surroundings using a boundary. And we would call this a closed

system, like the matter we have on our planet is a closed system. We do not get new matter.

We do not lose matter, generally to space. If we look at an open system like energy,

then there is flow from the surroundings into the system and vice versa. And so matter,

on our planet, is made up of a finite amount of atoms. And atoms are organized on the periodic

table. If we look at the simplest atom, hydrogen is going to have 1 proton and 1 electron.

It is highly reactive. Everything else in this column is also reactive because it has

a single valence electron. If we were to go to helium, helium could have 2 electrons in

this first shell. And since it has two it is incredibly stable. So is everything else

right here. If we were to grab an important biological atom, like carbon, it is going

to have 4 valence electrons. Two on the inside, four on the outside. So it is kind of the

lego block. We can build so many complex molecules off of that. And these are all through covalent

bonds. And so if we look at methane for example, methane is 1 carbon, 4 hydrogens. We are sharing

those electrons around the outside, so we have an incredibly stable molecule. And so

the atoms we have on the planet are going to differ depending on where we are. So if

we are looking at humans, think about this for a second, what are most of the atoms in

a human going to be? We let’s break it down by percent composition. We are mostly made

of water. And so it is mostly going to be oxygen and hydrogen. We are built out of carbon,

hydrogen is so low because it has such a small mass. We are also going to have nitrogen,

calcium, phosphorous. But in general we are going to be made by mass of oxygen. If we

were to look at the water, so the sea water right here, what is most of that? We could

break it up this way. It is mostly going to be oxygen as well. It is mostly made of water.

We are also going to have salts, like sodium and chloride. But it is mostly made of oxygen

and hydrogen. If we look at the rock, what is the rock mostly made up of? Oxygen. Now

there is going to be silicon. We are going to have aluminum and iron. But in general,

it is oxygen. And if we look at the atmosphere, that is going to mostly be nitrogen, but we

are also going to have a large amount of oxygen there as well, and other trace elements. And

so the oxygen in the atmosphere can eventually become oxygen in the rock. It could be oxygen

in the water. It can be oxygen in you. It has to be recycled because we are not creating

new atoms on our planet. Other important parts of this course will be understanding how water

is polar and that affects its behavior. Understanding pH and buffers. And then finally biological

molecules. So if you feel like you do not have a good enough background in these areas,

I have put videos down below and you could surely watch those. The next thing we should

deal with is energy. Energy was first quantified by James Joule using this apparatus. It has

a weight that would fall. It would spin paddles inside water and so you could measure changes

in the temperature using a thermometer. We were able to quantify energy, which is the

ability to do work. We measure that, a nod to James Joule as a joule. Now when you talk

about energy, generally you are going to hear things like watts. What is a watt? A watt

is going to be a joule per second. So that is time. So if you are talking about kilowatts

we are measuring the amount of energy that is being used over a given period of time.

Understanding the laws of thermodynamics is incredibly important. So if a car moves from

here to here it is converting energy. We are not creating energy we are converting it from

one form to another. So where is the energy before it was in that motion of the car? It

was in the gasoline. Before then it was in crude oil. Before then it was in ancient rain

forest. Before then it was given off by sunlight and used by that rainforest through photosynthesis.

But we are not creating new energy. We cannot create nor destroy energy. That is the first

law of thermodynamics. The second law deals more with systems. So we are going to have

inputs going into the system of the car. And then we are going to have outputs. And if

we look at the amount of energy that goes into the car, we could think of that gasoline,

the energy in the gasoline itself, we are using some that energy for the kinetic motion

of the car. But we are also losing some of that energy in friction and heat and sound.

And so what the second law of thermodynamics talks to is that at each interaction, at each

point along that pathway we are losing some of that useful energy. It is eventually becoming

heat which is non usable on our planet. And so understanding this balance is the area

of systems analysis. And this model works well. Think of it as a bathtub that has holes

in it. You have input. Then you have output. And if the amount of input matches the amount

of output then we are at what is called steady state. If we could see that. But what happens

if we have an increase inputs or an increase in outputs, what we can do is we can lose

that steady state. And maintaining that is feedback loops. So if we look at a real system

on our planet, a Swiss lake we would find that the level of the lake is going to be

steady state. And in nature we find that almost all systems in nature are going to be steady

state. So they are going to stay at the same level. Well how do they do that? They do that

through feedback loops. And so if you think about it, as we melt the snow. As we increase

the amount of water in the lake, the level goes up. We might have more drainage, and

that is going to keep the level the same. What else might happen? Since the lake is

really large we are going to have more evaporation off that surface and the level of the lake

is going to go down. Now we have a smaller surface area, there is less evaporation. Now

the level of the lake is going to go up. So that is a negative feedback loop. You could

look at that at the level of the earth system as well. And so the earth is being heated.

We are increasing green house gases. We are increasing the temperature on our planet.

And so there is a negative feedback loop that takes care of that. As we heat up the planet

there is more heat on the planet. What happens, we lose more of that heat to space. And so

that is a negative feedback loop. The problem is that we also have positive feedback loops

working on the planet right now. So an example, if we heat up the ocean, what happens? We

are getting evaporation off the ocean. That creates water vapor and water vapor is an

incredible greenhouse gas. What does that do? It heats up the earth which creates more

evaporation of water and more global warming. Another example, we could look at this white

area up here. So if we have a lot of ice that has a high albedo, it reflects a lot of the

light back into space. What happens as we start to melt that ice, then there is less

albedo. We are absorbing more of that heat and so we are increasing the temperature.

And so did you learn the following? I would pause the video right now and try to fill

in the blanks. But I will show you what it all means. And so we can think of remember

the earth as a system. It has inputs and outputs. We do systems analysis to measure that steady

state. Remember it could be negative or positive feedback loop. Remember the energy is an open

system versus a closed system of the matters. So the matter is conserved. And that whole

study is called thermodynamics. So hopefully you learned that. And I hope that was helpful.