Saturday, March 24, 2018

The Need for a Virtual Global Water Model


The Necessity for a New Global Water Model
Som Karamchetty

Problem:
There is a severe shortage of water in most countries. This shortage is in terms of clean and potable water for drinking and cooking. The shortage extends to other sectors like farming, industries, and a number of other uses.

Key Points:
All materials on earth only get recycled and undergo transformation. Except for sunshine, nothing comes from outside. Thermal radiation to outer space dissipates some of the energy. All the water we get on the earth is already here. No water leaves the planet nor enters it. Hence, it is unlikely that the earth would get any supply of fresh water from outer space. Furthermore, there is an enormous quantity of water in the oceans on the earth although it is salty and not directly usable. Although we complain about water shortage, the real problem is not getting enough water where and when we want it.
The earth will continue to receive energy from the sun so long as the sun exists and the earth rotates around the sun with no permanent obstruction in between. Consequently, technologies to reform and recycle water using solar energy should be the best option we have on earth to get plenty of water where we need and when we need it.
Solar evaporation of seawater is almost continual but it is of finite capacity. It may be possible to increase it to some extent. If we succeed in increasing the seawater evaporation and make sure that it falls on the land and not back into the oceans, we will get more fresh water on the land.
The next step is to keep the fresh water from running fast to the oceans. We should work on water infrastructure with good storage. In certain locations, land based fresh water evaporates due to the incidence of sunshine.

The Water Cycle:
The earth is lucky to have an enormous storage of water in the oceans. Electromagnetic energy from the sun (solar radiation) reaches the earth continuously. Owing to the incidence of thermal energy in the form of solar radiation, water in the oceans (as well as elsewhere) evaporates, moves up to higher altitudes and clouds are formed. Different parts of the earth react differently to the solar radiation in terms of absorption, radiation and retransmission. On the areas of earth where there is no or a little water, under the effect of solar radiation, the surface of the earth and the air gets warmer. The warmer air moves up. The net result is that the air is heated differentially at various locations. Together with other causes (earth’s rotation, gravity, and so on), there will be pressure differences and air movements in the earth’s atmosphere. The net result is that the water vapor laden air over the oceans moves up into higher altitudes and moves from one location to another. As the earth moves on its own axis, only parts of it are receiving solar radiation in different proportions and also for some periods of the day and other parts are exposed to cold deep space. Thus, any portion of the earth is going through periods of heating (due to exposure to the sun) and cooling (due to exposure to the cold deep space) in a day. Since the earth’s rotation is at an inclination, there are seasonal variations in the winds.
The water vapor in the air moves upwards and forms clouds, which move with the wind from high pressure regions to low pressure regions. With low temperatures at higher altitudes, the water vapor in the clouds condenses into water. At even higher altitudes, the water vapor in the clouds leads to the formation of snow. As water and snow are heavier than the surrounding air at the higher altitudes, they come down to earth as rain or snow fall. Some water returns to the oceans in the form of rain and snow fall and is of no immediate benefit to us. That water which comes down to the landed areas is of use to us in various ways. However, in some cases, upon reaching the mountains, the water flows downhill and along the rivers so fast that it reaches the ocean depriving us of any benefit.
There is an important water cycle that benefits us. Solar radiation evaporates sea water and fresh water becomes clouds and moves up high into the sky. The clouds move and rain forms thus causing rains and snowfall. Some of the rain and snowfall occurs over the sea and becomes salt water again. Thus, only that water which rains or snows on land becomes available to humans for use.

Ideal Situation:
What do we wish? We want the fresh water that comes down in the form of rain and snow in a certain fashion.
·         We want as much water as we like to use to come down to us on the land and not directly back to the oceans.
·         We want the water to come to us where we want and when we want it to suit our use patterns, such as in farming.
·         We want to store water so that fresh water is prevented from running back to the oceans.
·         We want to lessen the evaporation of freshwater, which is on the land, while we want unusable water on the land to evaporate.

Research Thrusts:
In order to fulfill our wishes (as noted above), we may have to do some research in science and engineering of the water movement in the atmosphere. Such research should have the following thrusts.
·         How to increase (essentially control the rate of water evaporation and precipitation) in the daily and diurnal cycles?
·         How to minimize the water returning as rain or snow to the oceans?
·         How to minimize water returning to the oceans as river flow (floods)?
·         How to get as much water as we need on the landed areas?
·         How to get controlled quantities of water when we need it?

Modeling:
The first task is to develop a model that analyzes the water flow in the atmosphere. This is perhaps possible by modifying the current atmospheric sciences (weather) models. These are currently used to forecast the weather patterns at various scales and time horizons.
The next task is to construct models that incorporate various large scale changes in the earth’s ecosystems and find their effects on weather. In such virtual scenarios, the following questions can be posed.
·         If large swaths of desert land are filled with (sea water filled) lakes and/or reforested, what would be the changes in weather pattern?
·         If large parts of the oceans in selected regions are covered (water is not allowed to evaporate under solar radiation), what changes in weather would be caused?
·         Once cause and effect relationship is established in virtual models, questions can be posed in terms of what should be done to get a certain set of effects?
·         With such models, it could be possible to augment (increase or decrease or change the timing or rate) the amount of rain or snowfall in certain areas of the earth.
·         In the end, such models might help us to harvest that water which now goes back to the oceans.
·         Of course, when such models are developed, the question if any of these mechanisms can be under sensible human control should also be addressed and answered.

Recommendations:
Develop a model that analyzes the mechanisms that cause the above described flows.
As we pass more of our jobs to intelligent machines, we should undertake such advanced modeling to address such harder mega problems. Of course, Artificial Intelligence might also come in to help us in this effort.

Useful References for more Information:

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