Name: Yuzhu Gong Due Date: 2015/1/13
Article Title: Facing the Freshwater Crisis
Author/Source: Scientific American
Article Title: Facing the Freshwater Crisis
Author/Source: Scientific American
A: List major ideas, concepts or key points - point by point
- Politicians there have allowed irrigation water to be shifted away from farming operations to cities and suburbs, while permitting recycled wastewater to be employed for landscaping and other nonpotable applications.
- Wise use of such power will become increasingly important as the years go by because the world’s demand for freshwater is currently overtaking its ready supply in many places, and this situation shows no sign of abating.
- By midcentury as much as three quarters of the earth’s population could face scarcities of freshwater.
- The most common solution is to hold surface water behind dams until the growing season, but the exposure evaporates much of this supply.
- Underground storage would limit evaporation loss.
- Keeping the demand for irrigation water in arid and semiarid areas down while still meeting the world’s future food requirements can be supported by supplying “virtual water” to those places.
- The notion of virtual water may sound initially like a mere accounting device, but provision of goods.
- Whatever benefits the world may accrue from virtual-water transfers, the populations of growing cities need real, flowing water to drink, as well as for hygiene and sanitation.
- The ever expanding demand for urban, water-based sanitation services can be reduced by adopting dry, or low-water-use, devices such as dry composting toilets with urine separation systems.
- Essentially, civil engineers can employ this technology to decouple water supplies from sanitation systems, a move that could save significant amounts of freshwater if it were more widely employed.
- During reverse osmosis, salty water flows into the first of two chambers that are separated by a semipermeable (water-passing) membrane.
- Despite the improvements in energy efficiency, however, the applicability of reverse osmosis is to some degree limited by the fact that the technology is still energy-intensive, so the availability of affordable power is important to significantly expanding its application.
B: Summarize the author's main point or idea
Summary of Author's Main Points:
As demand for freshwater soars, planetary supplies are becoming unpredictable. Existing technologies could avert a global water crisis, but they must be implemented soon. Global freshwater resources are threatened by rising demands from many quarters. Growing populations need ever more water for drinking, hygiene, sanitation, food production and industry. Climate change, meanwhile, is expected to contribute to droughts. Policymakers need to figure out how to supply water without degrading the natural ecosystems that provide it. n Existing low-tech approaches can help prevent scarcity, as can ways to boost supplies, such as improved methods to desalinate water. But governments at all levels need to start setting policies and making investments in infrastructure for water conservation now.
Summary of Author's Main Points:
As demand for freshwater soars, planetary supplies are becoming unpredictable. Existing technologies could avert a global water crisis, but they must be implemented soon. Global freshwater resources are threatened by rising demands from many quarters. Growing populations need ever more water for drinking, hygiene, sanitation, food production and industry. Climate change, meanwhile, is expected to contribute to droughts. Policymakers need to figure out how to supply water without degrading the natural ecosystems that provide it. n Existing low-tech approaches can help prevent scarcity, as can ways to boost supplies, such as improved methods to desalinate water. But governments at all levels need to start setting policies and making investments in infrastructure for water conservation now.
C: Reaction to the article
My Own Thoughts on the Topic:
The international community can reduce the chances of a global water crisis if it puts its collective mind to the challenge. We do not have to invent new technologies; we must simply accelerate the adoption of existing techniques to conserve and enhance the water supply. Solving the water problem will not be easy, but we can succeed if we start right away and stick to it. Otherwise, much of the world will go thirsty.
My Own Thoughts on the Topic:
The international community can reduce the chances of a global water crisis if it puts its collective mind to the challenge. We do not have to invent new technologies; we must simply accelerate the adoption of existing techniques to conserve and enhance the water supply. Solving the water problem will not be easy, but we can succeed if we start right away and stick to it. Otherwise, much of the world will go thirsty.