pollution is the introduction of contaminants into the natural environment. This can surpass the critical load of nutrients, which is the amount that can be absorbed without damage to the ecosystem. And this can also intensify biological magnification, which is that process where molecules accumulated biomass and concentrate at higher levels of the food web. So pollution could be particularly harmful to those higher trophic levels, including those predators. And just to show you an example of the human causes of pollution, look at the cityscape you convey arely. See the buildings there do toe all of this air pollution. Though I live in Los Angeles, so I can't really talk about air pollution, I guess now here in the North Pacific gyre, which is this area of the Pacific Ocean is located. What is fondly known, shall we say, is the Great Pacific garbage patch. There's a massive, massive amount of trash, mainly plastic, in the Pacific Ocean here, and what's particularly harmful about it is that most of this plastic is in particulate form, meaning it's going to be incredibly difficult to remove because of house um, particles are, and it's much easier for living organisms. Thio accidentally absorb it now. Climate change is obviously a major threat to global biodiversity, and climate change is the long term change in the statistical distribution of weather patterns. You can see the increase in carbon dioxide measurements in these charts here. This is, uh, just one thing that's contributing to global warming, which is the long term rise in global temperatures that you can see nicely charted in this graphic from NASA, which is from 2015. Everywhere that's in color on this map is off the average, and everywhere that's in a shade of yellow, orange red is above the average. So as you can see, 2015, uh, you know, incredibly hot year compared to what we're used thio Now this is in part due to greenhouse gasses like carbon dioxide, which are gasses in the atmosphere that absorb and emit thermal radiation. The issue is we are increasing the amount of greenhouse gasses in our atmosphere due to, for example, fossil fuel use, which increases the amount of carbon dioxide. Now, depletion of the ozone in the atmosphere is also an issue, but this is actually unrelated to climate change and global warming. It has some loose connections to it. But it is a separate thing, and the reason I'm pointing this out is because the media often confuses these two ideas and equates them, which is just wrong. But when does the media ever get science ideas, right? So what does ozone depletion actually do? Well, it allows more UV B light to pass through the atmosphere, and this is very harmful light. It's very damaging. It can do things like damage your DNA, so it's bad for life. So just to emphasize that point again, this is separate from climate change and global warming. With that, let's go ahead and flip the page.