waterclycle
CHAPTER ONE
1.1 Introduction Earth is the water planet with more than two-thirds of its surface covered by water. Most of life on Earth is also primarily composed of water; our cells, and those of plants and animals are composed of approximately 70 percent water. Vast quantities of water also cycle through the Earth 's atmosphere, oceans, land, and biosphere over both short and long time scales. This grand cycling of water is called the hydrologic cycle. Precipitation, evaporation, freezing and melting and condensation are all part of the hydrological cycle - a never-ending global process of water circulation from clouds to land, to the ocean, and back to the clouds. This cycling of water is intimately linked with energy exchanges among the atmosphere, ocean, and land that determine the Earth 's climate and cause much of natural climate variability. The water cycle is dominated by the oceans, where 96 percent of the water on Earth is found and where 86 percent of global evaporation occurs. Water is necessary to sustaining life on Earth, and helps tie together the Earth 's lands, oceans, and atmosphere into an integrated system.. The impacts of climate change and variability on the quality of human life occur primarily through changes in the water cycle. As stated in the National Research Council 's report on Research Pathways for the Next Decade (NRC, 1999): "Water is at the heart of both the causes and effects of climate change."
1.2 Overview of water cycle The water cycle, also known as the hydrologic cycle or H2O cycle, describes the continuous movement of water on, above and below the surface of the Earth. Water can change states among liquid, vapor, and solid at various places in the water cycle. Although the balance of water on Earth remains fairly constant over time, individual water molecules can come and go, in and out of the atmosphere. The water moves from one reservoir to another, such as from river to
1.1 Introduction Earth is the water planet with more than two-thirds of its surface covered by water. Most of life on Earth is also primarily composed of water; our cells, and those of plants and animals are composed of approximately 70 percent water. Vast quantities of water also cycle through the Earth 's atmosphere, oceans, land, and biosphere over both short and long time scales. This grand cycling of water is called the hydrologic cycle. Precipitation, evaporation, freezing and melting and condensation are all part of the hydrological cycle - a never-ending global process of water circulation from clouds to land, to the ocean, and back to the clouds. This cycling of water is intimately linked with energy exchanges among the atmosphere, ocean, and land that determine the Earth 's climate and cause much of natural climate variability. The water cycle is dominated by the oceans, where 96 percent of the water on Earth is found and where 86 percent of global evaporation occurs. Water is necessary to sustaining life on Earth, and helps tie together the Earth 's lands, oceans, and atmosphere into an integrated system.. The impacts of climate change and variability on the quality of human life occur primarily through changes in the water cycle. As stated in the National Research Council 's report on Research Pathways for the Next Decade (NRC, 1999): "Water is at the heart of both the causes and effects of climate change."
1.2 Overview of water cycle The water cycle, also known as the hydrologic cycle or H2O cycle, describes the continuous movement of water on, above and below the surface of the Earth. Water can change states among liquid, vapor, and solid at various places in the water cycle. Although the balance of water on Earth remains fairly constant over time, individual water molecules can come and go, in and out of the atmosphere. The water moves from one reservoir to another, such as from river to
References: Wikipedia, (2011). Climatology and Meteorology: Precipitation. Retrieved March 24, 2012. Website: Wikipedia.com/climatology-and-meteorology. Nouet, J. Et al (2007). Orbital and Millennial Antarctic Climate Variability over the Past 800,000 Year. Science 317 (5839): pp. 793–796. Website: http://.gov/ www.ncbi.nlm.nih punmed/17615306. The World Bank, (2009) Water and Climate Change: Understanding the Risks and Making Climate-Smart Investment Decisions. p.15. Retrieved March 23, 2012. Website:http://water.worldbank.org/water/publications/climate-and change –understanding – risks - and-making-climates martinvestment-decision. The Environmental Literacy Council. (2010). Water Cycle. Retrieved March 24, 2012. Website: http: // www. Enviroliteracy .org/ article.php/480.html Ababio, O.Y. (2007). New School Chemistry. 2nd edition. Heinemann Publisher Ltd. England Idodo, U. (1999). College biology 1st edition: Idodo-Umeh. Publishers Ltd. .Benin City Sarojini, I.R. (1993). Modern Biology. Africana – Feb Publisher Lt