Water And Life: Is There A Link?

Water is a tasteless, odourless, and nearly colourless liquid that covers about 71% of the Earth's surface and is essential for all life on, in, and above the Earth. It is composed of two atoms of hydrogen and one atom of oxygen and exists in gaseous, liquid, and solid states. Water plays an important role in the world economy, with approximately 70% of the fresh water used by humans going to agriculture. It is also used for entertainment, such as swimming, boating, and skiing, and is central to many industrial processes and cooking.

Water and the human body

Water is essential for the human body to function. Up to 60% of the human adult body is water, with some estimates ranging up to 75%. The brain and heart are composed of 73% water, the lungs contain about 83%, the skin contains 64%, muscles and kidneys are 79%, and even the bones contain about 31% water.

Water is a vital nutrient to the life of every cell, acting as a building material and helping to regulate internal body temperature through sweating and respiration. It also metabolizes and transports carbohydrates and proteins in the bloodstream, and assists in flushing waste through urination. Water acts as a shock absorber for the brain, spinal cord, and fetus, and helps to lubricate and cushion joints. It also helps to reduce the risk of urinary tract infections by keeping the bladder clear of bacteria. Water is also necessary to moisten mucous membranes in the lungs and mouth.

The human body can last for weeks without food but only days without water. The body loses water through breathing, perspiring, urine, and bowel movements, with most mature adults losing about 2.5 to 3 litres of water per day. Water loss may increase in hot weather, with high-altitude, and with prolonged exercise. Elderly people lose about 2 litres of water per day, and an air traveller can lose approximately 1.5 litres of water during a three-hour flight. Water loss needs to be replaced, and the body's water supply can be replenished through beverages and food that contain water. While most of the body's fluid needs should be met by drinking water, beverages such as soups, milk, 100% fruit juice, and decaffeinated teas are also options. Fruits and vegetables also contain a fair amount of water, and the body can get about 20% of its water requirements from solid foods alone. The process of digesting foods also produces a small amount of water, which can provide around 10% of the body's water requirements. The remaining 70% or so of water required by the body must come from other fluids.

Water is also important for the body due to its solvent properties. Water is an excellent solvent and can dissolve more substances than any other liquid, and its solvent properties affect all life on Earth.

Water and its states

Water is essential for all life on Earth. It is a tasteless, odourless, and colourless liquid at room temperature. It is composed of hydrogen and oxygen and exists in three states: solid, liquid, and gas. Water is one of the most plentiful compounds, covering around 71% of the Earth's surface, with seas and oceans making up most of the water volume.

The solid state of water is ice or snow. Ice is the more buoyant form of water, which is why it floats on water. Ice has a lower density than liquid water because the molecules of water occupy designated points in a lattice, resulting in fixed intermolecular distances. When ice melts, the surface meltwater slowly warms, sinks, and mixes nutrients throughout the water column. Water can be converted to ice by heating it to temperatures below 0 degrees Celsius, causing it to enter the solid state.

The liquid state of water is simply referred to as 'water' and is the state in which it is consumed by living organisms. It is an excellent solvent, dissolving more substances than any other liquid. This property of water makes it widely used in industrial processes, cooking, and washing. Liquid water is also essential for the metabolisms of living organisms, as it functions as a universal solvent and facilitates biochemical reactions. It is found in bodies of water such as oceans, seas, lakes, rivers, and streams.

The gaseous state of water is steam or water vapour. Water vapour is formed when liquid water undergoes physical changes such as evaporation and boiling. Water vapour can then revert to its liquid state through condensation. Water plays a crucial role in moderating Earth's climate by storing and transporting heat between the oceans and the atmosphere.

Water and the economy

Water is essential for all life on Earth. It is also invaluable for human uses, including industrial processes, cooking, and washing. Water is a vital nutrient for the life of every cell, and it assists in flushing waste from the body. Water is also necessary for the metabolic processes that provide energy to the human body.

Water plays an important role in the world economy. A World Bank report found that water scarcity, exacerbated by climate change, could hinder economic growth, spur migration, and spark conflict. Water scarcity could cost some regions up to 6% of their GDP. This is due to the combined effects of growing populations, rising incomes, and expanding cities, which will cause demand for water to rise exponentially while supply becomes more erratic and uncertain.

Agriculture uses the major share (69%) of global freshwater resources. Food security is a challenge that will become increasingly pressing over the coming decades as global demand for food and other agricultural products is projected to increase by 50% between 2012 and 2050. Water for food production is a major driver of environmental degradation, including depletion of aquifers, reduction of river flows, degradation of wildlife habitats, and pollution.

Water scarcity has a direct impact on the agricultural sector, reducing arable land and crop yields, which in turn affects production value and GDP. In regions where hydropower contributes to the energy mix, water scarcity can also limit energy production, with far-reaching economic consequences. Water-intensive industries are forced to curtail their activities, leading to job losses and a decline in economic output.

However, most countries can neutralize the adverse impacts of water scarcity by taking action to allocate and use water resources more efficiently. Improved water stewardship pays high economic dividends. When governments respond to water shortages by boosting efficiency and allocating water to more highly-valued uses, losses decline dramatically and may even vanish.

Water and sports

Water sports are physical activities that can be practised in indoor and outdoor salt or freshwater bodies. They are a great way to get in shape and improve your physical health. Water sports can be done in a variety of water bodies, from calm lakes to wavy oceans, and can be done with specialised equipment or just a swimsuit and a towel.

There are many different water sports to choose from, each with its own set of skills and endurance levels required. Some classic water sports include boating, canoeing, and kayaking. For those seeking an adrenaline rush, there are also more adventurous options like water skiing, kneeboarding, parasailing, and wakeboarding. These activities are not for the timid, as they involve being connected to a moving boat and require a combination of bravery, skill, and balance.

Other water sports that have gained popularity include stand-up paddleboarding, which can be done on calm water, and yoga on a paddleboard. Some people even enjoy fishing from a paddle board! For a futuristic experience, try a SEABOB, which will make you feel like you're flying above the water.

In addition to the health benefits of water sports, they are also good for the mind. The tranquil quality of water reduces stress, anxiety, and depression, and improves mood. Water sports can also help lower stress levels and keep you relaxed, which is beneficial for heart health and overall well-being.

Water sports are a great way to get exercise, connect with nature, and have fun. With so many options to choose from, there's something for everyone, whether you're looking for a peaceful activity or an adrenaline-pumping thrill.

Water and its colour

Water is often perceived as colourless, transparent, and odourless. However, water does have a colour, but the human eye cannot see it in small amounts of water. The colour of water is due to the selective absorption of light. When light passes through water, water absorbs the wavelengths that correspond to red light, and therefore, the transmitted light that we see is blue. Water absorbs mostly the lower frequencies, associated with red and orange, whereas blue and green are completely transmitted. The larger the volume of water, the more the absorption as a light beam travels through it, and so it appears more blue.

Pure water has a slight blue colour that becomes deeper as the thickness of the observed sample increases. The hue of water is an intrinsic property and is caused by selective absorption and scattering of blue light. The colour of water varies with the ambient conditions in which the water is present. Water molecules can vibrate in three different modes when they interact with light. The red, orange, and yellow wavelengths of light are absorbed, so the remaining light seen is composed of green, cyan, and blue wavelengths.

The depth of the water and the angle of the sun also contribute to variations in colour, with deeper waters appearing darker blue. Cleaner, more pure water backscatters light in the blue range, which makes it look blue. Deep waters like Crater Lake in Oregon look dark blue, but shallow waters that are very clear, such as those around many Caribbean islands, can appear light blue or turquoise. This happens because light reflects off the white, sandy bottom.

Water can also appear to be other colours, depending on the substances it carries. Water in natural bodies such as rivers, lakes, and oceans often contains dissolved minerals, algae, and organic matter that can impart a slight colouration. A high concentration of algae may give water a greenish tint, while dissolved organic materials can cause a yellowish hue. Waters that contain lots of sediment will backscatter light across the yellow to red range, making the water appear orange and muddy. A high concentration of minerals or heavy metals can also colour the water, such as in Río Tinto, a river in the province of Huelva, Spain.

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