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NARRATOR: Even though the ocean covers seventy percent of the Earth's surface, people tend to know more information about land than the sea. As a result, our understanding of the ocean is often incomplete or full of misconceptions. How well do you know the ocean? You may think Earth has five separate oceans. They're clearly labeled on our maps. But, in actuality, these are all connected, and part of one global ocean system. Ever wonder why the ocean is blue? You may have heard its because the water reflects the color of the sky. Not quite. Sunlight contains all the colors of the rainbow. When it hits the ocean, it gets scattered by the water molecules. Blue light is scattered the most, which is why the ocean appears blue. Even more interesting is that floating plants and sediments in the water can cause light to bounce in such a way for the ocean to appear green, yellow, and even red! Another idea some people have is that the sea floor is flat. Actually, just like land, the sea floor has canyons, plains, and mountain ranges. And many of these features are even bigger than those found on land. You may also think that our ocean's saltwater is just a mix of water and table salt. Not so. Seawater's "salt" is actually made of dissolved minerals from surface runoff. That is, excess water from rain and melting snow flowing over land and into the sea. This is why the ocean doesn't have the same level of salinity everywhere. Salinity varies by location and season. Finally, you may have heard that melting sea ice will cause sea levels to rise. In reality, sea ice is just frozen seawater, and because it routinely freezes and melts, its volume is already accounted for in the ocean. Sea levels can rise, however, from ice that melts off land and into the ocean. Understanding basic facts about the ocean is important since it affects everything from our atmosphere to our ecosystems. By knowing your ocean, you are better prepared to help protect it.

Hydronium/Hydroxide Balance When an acid dissolves in water, additional H3O+ is formed, increasing the concentration of H3O+. For example, the concentration of H3O+ might be increased from 10-7 M up to 10-5 M. That is 100 times more concentrated. Note that the pH, the number behind the negative sign in the exponent, changes from 7 to 5. This is why acidic solutions have pH values lower than 7.

How is global temperature regulated? An experimental representation - Simple experiments to help pupils understand how different parameters regulate temperature at the Earth's surface. Interaction at the Air-Water Interface, part 1 - A very simple experiment to demonstrate gas exchange and equilibration at the boundary layer between air and water. Pupils will also observe acidification of water due to CO2 introduced directly in the water. Interaction at the Air-Water Interface, part 2 - A second set of experiment to demonstrate gas exchange and equilibration at the boundary layer between air and water. Pupils observe a high atmospheric CO2 concentration will produce water acidification. Uptake of Carbon Dioxide from the Water by Plants - The following experiments will demonstrate the role of plants in mitigating the acidification caused when CO2 is dissolved in water. Carbon Dioxide Fertilization of Marine Microalgae (Dunalliela sp.) Cultures: Marine microalgae in different atmospheric CO2 concentration - An experiment designed to illustrate the impact of carbon dioxide on microalgal growth in the aquatic environment. Introduction to the principles of climate modelling - Working with real data in spreadsheets to create a climate model, students discover the global carbon budget and make their own predictions for the next century. Global carbon budget between 1958 and 2007 - Working with real global carbon budget data, students produce graphs to find the best representation of the data to make predictions about human CO2 emissions for the next century. This activity is also a nice application of percentages. Estimation of natural carbon sinks - Working with real global carbon budget data, students estimate how much of the CO2 emitted into the atmosphere as a result of human activities is absorbed naturally each year. How does temperature affect the solubility of CO2 en the water? - The following experiments will explore effects of water temperature on sol

The term ocean acidification is used to describe the ongoing decrease in ocean pH caused by human CO2 emissions, such as the burning of fossil fuels. It is the little known consequence of living in a high CO2 world, dubbed at the 2009 United Nations Climate Change Conference (COP15) as the "evil twin of climate change". The oceans currently absorb approximately half of the CO2 produced by burning fossil fuel; put simply, climate change would be far worse if it were not for the oceans. However, there is a cost to the oceans - when CO2 dissolves in seawater it forms carbonic acid and as more CO2 is taken up by the oceans surface, the pH decreases, moving towards a less alkaline and therefore more acidic state. Already ocean pH has decreased by about 30% and if we continue emitting CO2 at the same rate by 2100 ocean acidity will increase by about 150%, a rate that has not been experienced for at least 400,000 years. Such a monumental alteration in basic ocean chemistry is likely to have wide implications for ocean life, especially for those organisms that require calcium carbonate to build shells or skeletons. Ocean acidification is a relatively new field of research, with most of the studies having been conducted over the last decade. While it is gaining some attention among policy makers, international leaders and the media, scientists find there is still a lack of understanding.

The Great Dissolving Ocean acidification is changing the chemistry of our seas Doug George