Modern society is causing great damage to global society as a result of high industrial development, natural hazards, catastrophes, industrial accidents, and economic activity caused by changes in ecological situation by people with severe consequences.
Indeed, one of the worst disasters on our planet is the Aral Sea shrub. More than 35 million people live in the Aral Sea and its adjacent territories. Amudarya and Syrdarya deliver water to the Aral Sea. Aral Sea was relatively stable until 1960. The Amu Darya and Syrdarya rivers flows (55.0 cubic meters per year) and other water (9 cubic km) evaporated from the surface of the sea (65 cubic meters per year).
In the years of the former Soviet government, it became a country of multidisciplinary agricultural production based on intensive irrigation. Due to the use of water for irrigation of cotton and other cultivated areas resulted in a sharp decline in the Aral Sea contamination with the Amudarya and Syr Darya rivers. The sea level dropped to almost 20 meters. The area of water decreased by three times compared to the 1960s and the water volume decreased by 60 %.
The water has been concentrated and its levels are at regular intervals of 53 m absolute. The Aral Sea Basin has been eroding since 1961, and today the water has dropped down to almost 20 meters.
At present, the level of salinity of the Aral Sea is 47–49 g per liter of water, since only water evaporation and the low amount of water flowing through the rivers can lead to a steady increase in salt content in the Aral Sea.
The Aral Sea is a result of a decline in water levels, a rheological nature of natural resource use and a malicious breach of the integrity of natural components. The amount of water flowing to the Aral Sea is decreasing, as a use of agricultural production, as a result of the introduction of new landscapes and the use of unnecessary water.
Landslides are common in the mountainous areas of Central Asia. In this region, they are triggered by increasing steepness of slopes (owing to geological processes), seismic events, and meteorological and hydrological anomalies, as well as a variety of anthropogenic processes. Most landslides occur in foothill and mountain areas around 1000 to 2400 meters above sea level on slopes 19 degrees or steeper (depending upon soil type).
They can be hundreds of meters in width and as thick as 20 meters. Slides often remain compact after falling, with an area anywhere between four and four hundred hectares. Tajikistan contains around 50,000 landslide sites, of which 1,200 threaten settlements or facilities. Kyrgyzstan has at least 5,000 landslides, of which 3,500 at various levels of activity are located in the southern (Ferghana Valley) portion of the country. Significant portions of these countries lie in the moderate to high.
Almaty region in Kazakhstan, Tashkent, Samarkand, Surkhandarya, and Kashkadarya regions of Uzbekistan, and Ahal Province of Turkmenistan are also exposed to landslides, albeit not to the same degree.
Landslides in the Ferghana Valley have greater transboundary implications than those in other areas. Here and elsewhere, landslides can trigger other transboundary hazards, such as glacial lake outburst floods and release of toxic substances in river basins (particularly in the Mayli Suu area of the Ferghana Valley, as analyzed below). The number of landslides has grown in the past few decades, due to ongoing geodynamic movements, rising water tables, and increase in torrential rainfall, deforestation, and mining and excavation. Heightened groundwater infiltration from irrigation also contributes to landslide formation. All those circumstances break the slope stability in mountain and foothill zones. Haphazard and unplanned settlement has increased exposure to them. Hyrdometeorological anomalies play an important role in the beginning of landslide formation.
On the basis of long tern data, scientists in Uzbekistan have show a strong correlation between landslide activation and four- to five-year cycles of wet and dry years. Absolute values of seasonal and annual precipitation, snow and glacial melt (with subsequent rapid groundwater recharge), and intense precipitation play a key role in mobilizing landslides. According to the available projections of climate change in the region, landslides will become more widespread, owing to the increasing prevalence of extreme rainfall events and more rapid melting of glaciers.
However, available analyses do not suffice to precisely locate these hazards. Climate Variability and Change Exposure to meteorological hazards in Khorezm region must be assessed against a backdrop of rising climate variability and change. First and foremost, the region’s climate became noticeably warmer. In all regions, average annual temperature rose by 0.10 to 0.31 C every ten years.
In Turkmenistan and Uzbekistan the most significant changes were observed in the summer and autumn months. The frequency of extremely hot days (40C or above) has risen, while recurrence of low temperatures has diminished. There is no clear trend in precipitation during the twentieth century, and there are significant variations among locales within countries. Typically, average annual precipitation has followed a cyclical pattern, with a series of “wet” years followed by “dry” years. Overall, owing to rising temperatures, aridity has increased. Aridity has risen most sharply in the area surrounding the Aral Sea, owing to its desiccation.In Khorezm there are around 22 flash floods and mudflows per year an annual basis, formed mostly on the slopes and valleys. The high risk areas occupy around 12 % of the country and contain around 16 % of its population.
The arid continental climate of Central Asia frequent exposes large areas of Central Asia to meteorological drought conditions. Drought strikes in one or more areas almost every year (at varying scales). Severe and widespread meteorological drought (50 % or greater precipitation deficit) occurs in foothill areas around three times per century, while moderate drought (a 20–25 % deficit in seasonal precipitation) happens in three to four-year intervals. In the desert and semi-desert lowland areas, drought is more frequent (50 % or greater precipitation deficit every 10 years; 20 % deficit every five year. The most severe meteorological drought in recent memory hit Central Asia in 2000–01, when a precipitation deficit of 30–70 % was observed in most countries, coupled with above-average temperatures. The areas affected by widespread meteorological drought cut across national boundaries, i.e. it is a regional hazard.
References
- Lee Davis (2008). "Natural Disasters". Infobase Publishing. p.7. ISBN 0–8160–7000–8
- «Avalanche!». WorldWar1.com. Retrieved 2015–01–12.
- Gibbons, Ann (19 January 2010). «Human Ancestors Were an Endangered Species». ScienceNow.
- MSN Encarta Dictionary. Flood. Retrieved on 2006–12–28. Archived 2009–10–31.
- Glossary of Meteorology (June 2000). Flood. Archived 2007–08–24 at the Wayback Machine Retrieved on 2009–01–0
