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"Recognising ocean acidification in deep time: An evaluation of the evidence for acidification across the Triassic-Jurassic boundary Sarah E. GreeneCorresponding author contact information, 1, E-mail the corresponding author, Rowan C. Martindale1, E-mail the corresponding author, Kathleen A. Ritterbush E-mail the corresponding author, David J. Bottjer E-mail the corresponding author, Frank A. Corsetti E-mail the corresponding author, William M. Berelson E-mail the corresponding author Department of Earth Sciences, University of Southern California, Los Angeles, California, USA 90089 Received 22 July 2011. Accepted 17 March 2012. Available online 5 April 2012. While demonstrating ocean acidification in the modern is relatively straightforward (measure increase in atmospheric CO2 and corresponding ocean chemistry change), identifying palaeo-ocean acidification is problematic. The crux of this problem is that the rock record is a constructive archive while ocean acidification is essentially a destructive (and/or inhibitory) phenomenon. This is exacerbated in deep time without the benefit of a deep ocean record. Here, we discuss the feasibility of, and potential criteria for, identifying an acidification event in deep time. Furthermore, we investigate the evidence for ocean acidification during the Triassic-Jurassic (T-J) boundary interval, an excellent test case because 1) it occurs in deep time, beyond the reach of deep sea drilling coverage; 2) a potential trigger for acidification is known; and 3) it is associated with one of the 'Big Five' mass extinctions which disproportionately affected modern-style invertebrates. Three main criteria suggest that acidification may have occurred across the T-J transition. 1) The eruption of the Central Atlantic Magmatic Province (CAMP) and the associated massive and rapid release of CO2 coincident with the end-Triassic mass extinction provide a suitable trigger for an acidification event (

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