Science by Email 9 December 2011

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	9 December 2011
The Australian Government funds research to monitor and reduce the carbon emissions from livestock. News: Climate change cooperation By Patrick Mahony Climate change is a complex issue and one that crosses international borders – the actions of one country may impact the citizens of another. Climate change is not just a scientific or environmental issue, it is a social and political issue as well, and one that will require cooperation at many levels. The United Nations Framework Convention on Climate Change (UNFCCC) is a treaty created in 1992. Most countries in the world are part of this treaty, and they have agreed to cooperate to address the issue of climate change. Representatives from governments around the world are currently meeting in Durban in South Africa at the United Nations Climate Change Conference to talk about issues relating to the UNFCCC. But what are they planning to do? One topic that the conference will discuss is the impact of climate change on food security. Food security exists when people have access to enough safe, nutritious food to lead a healthy life. Climate change threatens food security because of its potential to reduce the amount of land available for agriculture, lower crop yields and increase the price of food. At a local level, the Australian government funds scientific research such as developing drought-resistant crops and reducing greenhouse gas emissions from livestock, as well as working with farmers to make farming practices more sustainable. At an international level, Australia provides aid to developing countries to help them deal with the effects of climate change on their food supply. Australian scientists also provide advice on how to respond to climate change. Scientists play an important role in providing scientific evidence to governments so that they can make informed decisions. For example, CSIRO Chief Executive Dr Megan Clark was part of an independent international commission that provided a report to the United Nations Climate Change Conference on the issue of climate change and its impacts on food security. The report recommends actions based on evidence provided by research. This includes moving towards a sustainable food system by implementing climate-resilient agricultural production, using resources more efficiently, reducing food wastage, encouraging adequate nutrition and promoting healthy eating choices. Climate change and food security are global challenges that will not be solved by one group of people. They will require the combined efforts of farmers, scientists, governments, international organisations and others in order to be managed. More information Background on the UNFCCC: The international response to climate change Department of Agriculture, Fisheries and Forestry: Climate Change Research Program World Health Organisation: Food security Careers Open your mind: careers in agriculture
You will need these materials.   Rub one side of the board with wax.   Place an ice cube at one end of the unwaxed side of the board. Slowly lift this end of the board.   When the ice cube slides down, stop lifting the board and measure the height. Repeat for the waxed side of the board.   Try this: Slippery slope   You will need Ice cubes Wax candle or crayon Wooden board or plank Ruler What to do Rub one side of the board with the candle so that it is covered in a thin layer of wax. Lay the board flat on a table, waxed side down. Place an ice cube at the end of the board. Slowly lift this end of the board. When the ice cube slides down the board, stop lifting. Measure the height with the ruler. Flip the board over and repeat with the waxed side. Compare the two heights. What's happening? Before you lift the board, there are two forces to consider – gravity pulling the ice cube down and the force of the board pushing against it. As you lift the board, the resistance force of the board changes. This resistance at an angle is called friction. Gravity pulls the ice cube down the slope while friction prevents it moving. When the slope is steep enough, the force from gravity is greater than that of friction, and the ice cube slides down. The lower the friction is between the surfaces, the lower the angle of elevation needs to be for the ice cube to slide. Wood is composed of a number of different types of molecules, and some of these attract the water molecules in the ice. This attraction combined with the rough surface of the board means there is a relatively large amount of friction between the ice cube and the board. Wax molecules, on the other hand, repel water molecules. This repulsion, along with the smoother surface created by the wax means that there is less friction between the ice cube and waxed board. Applications A substance that is used to reduce friction between moving parts is called a lubricant.             Friction generates heat and causes wear that can damage moving parts. Lubricants are used in many machines to reduce friction and thus extend their working life. An example is a car engine which uses a lubricating oil to reduce friction. Skiers also use wax to reduce friction between snow and their skis. This is so they can move more easily down the ski slopes. Try another Science by Email activity about friction More information How lubricants work in engines By Patrick Mahony View online version Quiz questions 1. What is negative thermal expansion? 2. Cirrus and cumulus are types of what? 3. What might be tested using the Turing test? 4. What do aerobically respiring organisms need to function that anaerobically respiring organisms don’t? 5. When did the formation of the Antarctic ice sheets start accelerating: a) 153 000 years ago; b) 12 million years ago; c) 27 million years ago; or d) 34 millions years ago? Did you know? Marine life may have to relocate and adapt to climate change faster than land species, according to research by CSIRO’s Climate Adaptation Flagship. Website Watch it! Watch this clever dolphin as it plays with bubbles underwater! See it! Check out these beautiful photos of the environment. Caves, Saturday 10 December at 9.00 am on Network Ten This week on SCOPE we explore the natural wonders of the amazing cavernous world of caves! From how they are formed to what exactly lives down there and why, Dr Rob heads underground to SCOPE out all the answers. So join the team as once again the ordinary becomes extraordinary, under the SCOPE. Next episodes: Thursday 15 December: Summer sports Saturday 17 December: Structures Want to have your own episodes of SCOPE to watch whenever you feel like it? Click here to download them directly into your iTunes folder, or go here to download iTunes. Charges apply. Quiz answers 1. Negative thermal expansion occurs when a substance expands in volume with a decrease in temperature. 2. Cirrus and cumulus are types of clouds. 3. The Turing test is used to test artificial intelligence. 4. Aerobically respiring organisms require oxygen in order to survive. 5. d) 34 million years ago. Research from the University of New South Wales showed that the acceleration of the formation of the ice sheets coincided with a drop in atmospheric carbon dioxide levels. Science by Email is a CSIRO publication. The Department of Agriculture, Fisheries and Forestry and bankmecu are proud partners of Science By Email. Editor: Mike McRae | Manage your subscription | FAQ

 

 

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