What human activities affect the water cycle?

Answer 1

The earth's water supply remains constant, but man is capable of altering the cycle of that fixed supply. Population increases, rising living standards, and industrial and economic growth have placed greater demands on our natural environment. Our activities can create an imbalance in hydrologic equation and can affect the quantity and quality of natural water resources available to current and future generations.

Water use by households, industries, and farms has increased. People demand clean water at reasonable costs, yet the amount of fresh water is limited and the easily accessible sources have been developed. As the population increases, so will our need to withdraw more water from rivers, lakes and aquifers, threatening local resources and future water supplies.

A larger population will not only use more water but will discharge more waste water. Domestic, agricultural, and industrial wastes, including the intensive use of pesticides, herbicides and fertilizers, ofter overload water supplies with hazardous chemicals and bacteria. Also, poor irrigation practices raise soil salinity and evaporation rates. These factors contribute to a reduction in the availability of potable water, putting even greater pressure on existing water resources.

Large cities and urban sprawl particularly affect local climate and hydrology. Urbanization is accompanied by accelerated drainage of water through road drains and city sewer systems, which even increases the magnitude of urban flood events. This alters the rates of infiltration, evaporation, and transpiration that would otherwise occur in a natural setting. The replenishing of ground water aquifers does not occur or occurs at a slower rate.

Together, these various effects determine the amount of water in the system and can result in extremely negative consequences for river watersheds, lake levels, aquifers, and the environment as a whole. Therefore, it is vital to learn about and protect our water resources.

When we talk about the water cycle moving water vapor in and out of the atmosphere, there are no human activities that can affect that. Water vapor will still evaporate into the atmosphere whether the ground water is dirty or clean.

Answer 2

A:

• The earth's water supply stays the same but humans can alter the cycle. As population increases, and living standards rise this can increase the demand for water.
• Humans impact the water cycle by polluting the water in rivers, streams, reservoirs etc.
• We are polluting it with harmful chemicals and disgusting substances. Technically we as humans cannot alter the water cycle, however, we can mess it up by dumping waste into the ocean.
• When we talk about the water cycle moving water vapor in and out of the atmosphere, there are no human activities that can affect that. Water vapor will still evaporate into the atmosphere whether the ground water is dirty or clean.
• These reasons can create an imbalance and change the quality and quantity of the water.

Answer 3

Two human activities include:
1. Addition of oxides of sulfur and nitrogen in air that causes acid rain.
2. Polluting water bodies.