WEBVTT 00:00:14.989 --> 00:00:20.288 Carbon dioxide, or CO2, is the main greenhouse gas in climate change. 00:00:20.288 --> 00:00:23.656 So how does CO2 get into our atmosphere? 00:00:23.656 --> 00:00:28.256 Well, carbon is part of a cycle. It starts with the sun, 00:00:28.256 --> 00:00:31.788 which heats the Earth's surface with more energy 00:00:31.788 --> 00:00:34.421 in one hour than the whole world uses in a year. 00:00:34.421 --> 00:00:37.771 Plants, which are kind of like biological chefs, 00:00:37.771 --> 00:00:40.838 take that sunlight, and then suck in some CO2 from the air, 00:00:40.838 --> 00:00:42.605 mix them together, and BAM! 00:00:42.605 --> 00:00:46.188 They create a stored form of energy, in the form of carbohydrates 00:00:46.188 --> 00:00:49.121 such as glucose and sucrose. 00:00:49.121 --> 00:00:52.072 The process is called photosynthesis. 00:00:52.072 --> 00:00:54.239 When animals like us eat those plants 00:00:54.239 --> 00:00:58.388 our stomachs convert that food back into energy for our own growth. 00:00:58.388 --> 00:01:00.771 Greenhouse gases are a byproduct of this process, 00:01:00.771 --> 00:01:03.138 and are released through waste. 00:01:03.138 --> 00:01:08.205 If those plants die, they decompose, and tiny microorganisms break down those carbohydrates 00:01:08.205 --> 00:01:12.656 and again, release greenhouse gases as a byproduct. 00:01:12.656 --> 00:01:18.055 As you see, energy originates from the sun. It is then transferred as it moves through the food chain. 00:01:18.055 --> 00:01:24.287 But sometimes, carbon based organisms like plants or animals get stuck in the earth. 00:01:24.287 --> 00:01:28.138 When this happens, they're compressed under tons of pressure, 00:01:28.138 --> 00:01:30.240 and turned into carbon-based fossil fuels 00:01:30.240 --> 00:01:33.604 like oil, coal or natural gas. 00:01:33.604 --> 00:01:37.955 Since the Industrial Revolution, humans have been pulling those fossil fuels out of the ground 00:01:37.955 --> 00:01:41.572 and burning them, activating the stored energy 00:01:41.572 --> 00:01:44.305 to make electricity and power engines. 00:01:44.305 --> 00:01:52.671 But the thing is it also releases millions of years worth of stored CO2 back into the air. 00:01:52.671 --> 00:01:57.021 In addition, humans breathe in oxygen and breathe out CO2. 00:01:57.021 --> 00:02:00.188 But plants do the opposite. 00:02:00.188 --> 00:02:04.620 Trees suck up huge amounts of CO2, which balances the cycle. 00:02:04.620 --> 00:02:09.304 Thus, deforestation reduces the plants that store CO2. 00:02:09.304 --> 00:02:11.939 We're attacking the cycle from both sides. 00:02:11.939 --> 00:02:16.256 Think of it like a computer. A computer can operate a few programs at a time, right? 00:02:16.256 --> 00:02:20.421 Normally, when you've finished with a document, you save, and you close it, 00:02:20.421 --> 00:02:22.921 so as not to overwork the computer. 00:02:22.921 --> 00:02:26.071 Then, imagine you stopped closing your documents. 00:02:26.071 --> 00:02:28.505 So they were all open at once. 00:02:28.505 --> 00:02:30.355 Your computer wouldn't be able to process it all. 00:02:30.355 --> 00:02:33.971 It would start to slow down, and then to freeze, and eventually it would crash. 00:02:33.971 --> 00:02:38.471 Which might be where our environment is heading if we keep overloading the carbon cycle. 00:02:38.471 --> 00:02:41.688 So is there any way to rebalance the ecosystem? 00:02:41.688 --> 00:02:46.771 What about technology? Technology is defined as a technique to solve a problem. 00:02:46.771 --> 00:02:52.005 And so, sustainable technologies are those whose output is equal to their input. 00:02:52.005 --> 00:02:54.855 They do not create negative externalities, 00:02:54.855 --> 00:02:57.788 such as CO2, in the present or the future. 00:02:57.788 --> 00:03:01.288 They sort of cancel themselves out to solve the problem. 00:03:01.288 --> 00:03:04.788 To achieve this, we need to invent sustainable technologies. 00:03:04.788 --> 00:03:09.005 If we put all the ideas and technologies ever created into one circle, 00:03:09.005 --> 00:03:12.438 then invention is the pushing of the boundaries of that circle. 00:03:12.438 --> 00:03:15.672 And the area outside of the circle is infinite, 00:03:15.672 --> 00:03:18.989 meaning the potential for invention is limitless. 00:03:18.989 --> 00:03:22.556 Think about some of the incredible clean technologies we have today. [Wind; Electric & Solar Cars; Biogas] 00:03:22.556 --> 00:03:25.439 [Biofuels; Photosynthetic Algae; Compost] All those ideas have one thing in common. 00:03:25.471 --> 00:03:29.288 They all came from people. People innovate. 00:03:29.288 --> 00:03:34.921 People create. It's the limitless potential of creative people 00:03:34.921 --> 00:03:39.371 to build unimagined technologies that is going to stop climate change 00:03:39.371 --> 00:03:45.455 and rebalance the ecosystem. And that is something to be hopeful about.