However, while the chemistry is predictable, the details of the biological impacts are not. Overall, it's expected to have dramatic and mostly negative impacts on ocean ecosystems-although some species (especially those that live in estuaries) are finding ways to adapt to the changing conditions. In fact, the shells of some animals are already dissolving in the more acidic seawater, and that’s just one way that acidification may affect ocean life. Such a relatively quick change in ocean chemistry doesn’t give marine life, which evolved over millions of years in an ocean with a generally stable pH, much time to adapt. As those surface layers gradually mix into deep water, the entire ocean is affected. (Scientists call this stabilizing effect “buffering.”) But so much carbon dioxide is dissolving into the ocean so quickly that this natural buffering hasn’t been able to keep up, resulting in relatively rapidly dropping pH in surface waters. Scientists formerly didn’t worry about this process because they always assumed that rivers carried enough dissolved chemicals from rocks to the ocean to keep the ocean’s pH stable. In the past 200 years alone, ocean water has become 30 percent more acidic-faster than any known change in ocean chemistry in the last 50 million years. Even though the ocean is immense, enough carbon dioxide can have a major impact. When carbon dioxide dissolves in seawater, the water becomes more acidic and the ocean’s pH (a measure of how acidic or basic the ocean is) drops. But in the past decade, they’ve realized that this slowed warming has come at the cost of changing the ocean’s chemistry. Since the beginning of the industrial era, the ocean has absorbed some 525 billion tons of CO 2 from the atmosphere, presently around 22 million tons per day.Īt first, scientists thought that this might be a good thing because it leaves less carbon dioxide in the air to warm the planet. At least one-quarter of the carbon dioxide (CO 2) released by burning coal, oil and gas doesn't stay in the air, but instead dissolves into the ocean. discuss some of the science concepts that underlie the carbon cycle.Ocean acidification is sometimes called “climate change’s equally evil twin,” and for good reason: it's a significant and harmful consequence of excess carbon dioxide in the atmosphere that we don't see or feel because its effects are happening underwater.use inference skills to answer some of the quiz questions.use reading literacy skills to locate information and answer the quiz questions.use scientific literacy skills to read and interpret features of the carbon cycle diagram.The quiz combines scientific literacy with reading literacy and provides students with an opportunity to practise the science capability ‘Interpreting representations’.Īlternatively, the quiz can be used as an introductory tool to gauge students’ prior knowledge or as a summative assessment.īy the end of this activity, students should be able to: In this activity, students use the interactive carbon cycle diagram to explore the global carbon cycle and to answer questions in an online or paper-based quiz.
The carbon cycle is a visualisation of the processes that move and store carbon between living and non-living things. Carbon moves through the Earth’s system in many different ways.
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