Flooding, long-term

In the long term (20-40 years), the overall domestic HW system is subject to pinhole leaks stemming from the galvanic corrosion of steel riser pipes (usually located in inaccessible areas), with resultant flooding within the building. Galvanic corrosion develops because these systems typically contain a wide range of mixed metals such as black... 

Water resources decision making in many areas, particularly arid and semi-arid climates such as the American West, depends on interannual to decadal variations in surface water availability. In addition to more predictable seasonal differences, runoff tends to exhibit long-term trends alternating between flood and drought periods. Figure 6-10 shows historical wet and dry periods based on streamflow records for 50 world rivers. For the most part, these periods are consistent on a regional basis, though they appear to alternate on a hemispheric scale. 

Thomdycraft VR, Benito G, Rico M et al (2005) Long-term flood discharge record derived from slackwater flood deposits of the Llobregat River, NE Spain. J Hydrol 313 16—31... 

Tan, JS, Wang, JJ, Flood, V, Rochtchina, E, Smith, W, and Mitchell, P, 2008. Dietary antioxidants and the long-term incidence of age-related macular degeneration The Blue Mountains Eye Study. Ophthalmology 115, 334-341. 

The most dangerous in their long-term effects are the tailing dumps containing radio-active waste, which are also located in the vicinity of the Dnepr bed or near smaller rivers in the Dnepr catchment basin. Many tailing dump levees and toxic radio-active waste hoarder dams are in extremely poor condition. They can be easily destroyed by natural factors (minor earthquakes, floods, rise of subterranean waters) or by man-made acts (like a terrorist act with the use of explosives), with all ensuing consequences. 

If the source of water is relatively unlimited (long-term flooding), the downward migrating water will displace air from the pores and migrate according to Darcy s... 

However, the last few years have also seen a growing awareness of the problems inherent in using the semiconductor-electrolyte interface as a means of solar-energy conversion. Very long-term stability may not be possible in aqueous electrolytes and no oxide material has been identified that has properties suitable for use as a photoanode in a photoelectrolysis cell. Highly efficient photovoltaic cells are known, both in aqueous and non-aqueous solutions, but it is far from clear that the additional engineering complexity, over and above that required for the dry p-n junction photovoltaic device, will ever allow the "wet photovoltaic cells to be competitive. These, and other problems, have led to something of a pause in the flood of papers on semiconductor electrochemistry in the last two years and the current review is therefore timely. I have tried to indicate what is, and is not, known at present and where future lines of development may lie. Individual semiconductors are not treated in detail, but it is hoped that most of the theoretical strands apparent in the last few years are discussed. 

Natural disasters can be categorized as acute or slow in their onset (Noji, 1996). They are predictable because they cluster in geographic areas. Natural hazards are unpreventable and, for the most part, uncontrollable. Even if quick recovery occurs, natural disasters can have long-term effects. Natural disasters with acute onsets include events such as avalanche blizzard or extreme cold earthquake fire flood heat wave hurricane, cyclone, or typhoon tornado tsunami or storm surge volcanic eruption and wildfire. Natural hazards with a slow or gradual onset include deforestation, desertification, drought, and pest infestation. The most important natural disasters and examples of their environmental effects are listed in Table 17.1. 

The floods that accompany a tsunami result in potential health risks from contaminated water and food supplies. Loss of shelter leaves people vulnerable to exposure to insects, heat, and other environmental hazards. Further, the lack of medical care may result in exacerbations of chronic disease. Tsunamis have long-lasting effects and recovery necessitates long-term surveillance of infectious and water- or insect-transmitted diseases, an infusion of medical supplies and medical personnel, and the provision of mental health and social support services. 

By improving "sweep" and "mobility control," surfactant-based methods offer the most promising ways to alleviate these problems. This use of surfactants appears to be just on the verge of commercialization for steam flooding. Because miscible CO2 flooding has been commercialized more recently, the use of surfactants to improve gas-flood EOR has not yet been commercialized. Conceivably, however, the long-term viability of gas flooding could prove to be dependent on the success of current research efforts in the use of surfactants to alleviate "bypass" problems. 

Worbes, M. 1985. Structural and other adaptations to long term flooding by trees in Central Amazonia. Amazoniana 9(1) 459-484. 

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