BIO 220 W7 Discussion Question One
BIO 220 W7 Discussion Question One
Describe the hydrologic cycle and various methods of water use and management. What changes might occur in the hydrologic cycle if our climate were to warm up or cool down significantly?
Hydrological cycle is also known as the “water cycle”; it is the normal water recycling system on Earth (Fig. 3.4). Due to solar radiation, water evaporates, generally from the sea, lakes, etc. Water also evaporates from plant leaves through the mechanism of transpiration. As the steam rises in the atmosphere, it is being cooled, condensed, and returned to the land and the sea as
BIO 220 W7 Discussion Question One
precipitation. Precipitation falls on the earth as surface water and shapes the surface, creating thus streams of water that result in lakes and rivers. A part of the water precipitating penetrates the ground and moves downward through the incisions, forming aquifers. Finally, a part of the surface and underground water leads to sea. During this trip, water is converted in all phases: gas, liquid, and solid. As mentioned above, water always changes states between liquid, vapor, and ice, with these processes happening in the blink of an eye and over millions of years.
The hydrological cycle is intimately linked with changes in the atmospheric temperature and radiation balance. Warming of the climate system in recent decades is unequivocal, as it is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice, and rising of the sea level globally.
It is expected that the hydrological cycle will be affected from global warming due to the enhanced greenhouse effect [10]. The hydrological cycle may be strengthened with more precipitation and more evaporation, but the extra precipitation will be unequally distributed around the globe. It is expected that some areas of the world may see significant reductions in precipitation or even more major variations in the timing of wet and dry seasons. Many aspects of the economy, environment, and society are dependent upon water resources, and changes in the hydrological resource base have the potential to severely impact upon environmental quality, economic development, and social well-being.
The hydrological cycle in Afghanistan is one of the high altitude snow and rain, commonly torrential, which produces catastrophic downstream effects such as avalanches and floods. Most of the precipitation that drives the river-flow lifeblood of the country outward from the tops of the watersheds in Afghanistan diminishes toward the borders from its highs in the northeast of the nation. The main river systems, listed in a counterclockwise direction around Afghanistan. include the Amu Darya, Hari Rud–Murgab, Helmand–Arghandab, and the Kabul, each of which is discussed in more detail herein. Lakes in Afghanistan include glacial, landslide-dammed, carbonate-precipitate types, diastrophic (tectonic and volcanic) lakes, tectonic—mixed types, and multiple deflation-basin sorts of lakes, many of which are intermittently dry. Underground water in Afghanistan occurs in aquifer basins throughout the country, with the basin beneath Kabul City undergoing severe drawdown.