Global distribution of water
Global water supplies are not evenly distributed. Some places have a A location that has more water than required., whereas others have a A place that has less water than required..
Exploring the issues linked to distribution and access to water in different parts of the world
Global water supply
Different countries have different amounts of water. Generally speaking:
- Countries along the The line around the centre of the Earth, parallel to the Tropics of Cancer and Capricorn. have enough water. Warm, moist air rises here, which causes high levels of rainfall.
- Countries to the north of the Equator (at a latitude of approximately 30掳) have A lack of available water for everyone.. This is when there isn't enough rainfall. Cooler, dry air falls here and so it is very Extremely dry..
- Countries to the south of the Equator (at a latitude of approximately 30掳) also experience some A shortage of fresh water.. It is less severe than in the north because there is less land in the southern hemisphere.
- Countries with the highest latitudes (those that are furthest away from the Equator) have enough rainfall to provide plenty of fresh water.
- Exceptions to this rule exist in countries with high The average number of people in a certain area. , eg the UK, or countries where poverty causes When water is too expensive for many people to afford., eg Nigeria.
Reasons for increasing water consumption
Water consumption has been rising globally over time. There are two main reasons for this.
Rising population
Everyone needs water in order to survive. Water makes up at least 60% of a person's bodyweight and it is needed for all bodily functions. People also use water for Cleanliness., cooking and cleaning. The population of the world is increasing, but there is only a fixed amount of fresh water available for people to use.
Economic development
As countries develop, their water use increases. People in wealthier nations have water delivered into their homes via pipeline. Modern appliances, such as dishwashers and washing machines, use a lot of water. Farming as a business., industry and tourism in A country with a gross national income per capita above US $12,735 (according to the World Bank) such as the Netherlands and the UK. consume vast quantities of water too . The The amount of water used by a country, both domestically and through imports. of HICs is much higher than Based on the World Bank's income classifications, a LIC has a gross national income (GNI per capita) of $1,045 or lower.. As more countries develop, the demands on water will increase.
Water footprint
A water footprint is defined as the total volume of freshwater consumed and polluted for the production of the goods and services used by the consumer. It is calculated by adding the direct water use by people and their indirect water use.
Case study: drought in California
California is a coastal state in western USA with a population of around 39 million residents. It has A natural region that experiences less than 250 mm of precipitation and has either hot or cold temperatures throughout the year. inland to the east but there is usually plenty of rainfall to provide water along the coast. There are around 24 million acres, or 9.7 million ha (hectares) of farmland in California. Roughly 40% of the country's vegetables, fruit and nuts are grown in the state which generates around $50 billion each year.
California has experienced A long period of low rainfall that creates a major shortage of water. since 2011. Irrigated crops use a lot of the freshwater supplies in the region. Rising temperatures, falling rainfall levels and a growing population are also contributing to the problem.
The drought has lowered Where water is stored in rocks beneath the ground. levels. This can cause lots of problems, such as:
- A fall in land levels. - this is a fall in the level of the land, which damages properties.
- Sea water intrusion - this is when sea water flows in to groundwater spaces known as Naturally occurring underground water stores.. People cannot drink sea water as it is salty.
- Wildfires - vegetation becomes very dry and intense heat, such as lightning strikes, can set it alight easily.
- A community of animals, plants and microorganisms, together with the habitat where they live. damage.
In 2014 California introduced a new law called the Sustainable Groundwater Management Act or SGMA. It aimed to regulate the use of groundwater supplies and make ground supplies sustainable by the year 2040 . However, many years after this law was put in place, wells are still drying up. There are still many improvements to make before the targets can be met.