Drought is a multi-causal and complex environmental issue, and can have serious socioeconomic consequences. Recently, IPCC (the Intergovernmental Panel on Climate Change) in Fourth Assessment Report (AR4) concluded that South Asia and the Middle East would experience sever, prolonged droughts as a result of global climate changes, explicitly the increase in greenhouse gases in the atmosphere (IPCC, 2007). Drought is a weather-related natural disaster whose effect is aggravated by human activities. Sometime drought affects large regions and even several countries for a long period of time. Drought has a serious impact on food productivity of a land, and even on the life expectancy of inhabitants. The aftermath of drought involves in socioeconomic, ecological issues (WGA, 1996) (Jeyaseelan, 2005; Pongracza et al., 1996). Iran encompassing drylands has been periodically jeopardized by drought events, which have devastatingly affected society and environment (Shamsipour et al., 2008). Therefore, the study of drought needs several sources of datasets. In other words, the design of a planning project for a region for sustainable development, the acquisition of updated data is critical, particularly for countries with arid to semi-arid climates.
The recent innovations in remote sensing methods have brought new solutions to study of environmental problems in geosciences. In the assessment of natural hazards like drought, remote sensing provides rapid, instant spatial data about the natural phenomena; they are useful in decision-makings as well as weather forecasts (Sunyurp et al., 2004). The monitoring of drought via remote sensing depends on the factors that cause drought (Jeyaseelan, 2005). Drought indicators and variables, obtained through remotely sensed data, can carry some uncertainties, which is induces by the sensitivity of factors, or their dependency to weather and environment conditions. Additionally, some non-standard algorithms might lead to wrong estimation of drought intensity.
More effective methods for increase accuracy of assessment and analysis of remotely sensed data are applying models which can combine in data layers. Geographic Information Systems (GIS) are used to combine the layers of data in the modeling of drought. Recently, space technologies, such RS and GIS, and the numerical modeling techniques have been developed as powerful tools for the ecological assessment of environment (Krivtsov, 2004; MacMillan et al., 2004; Store and Jokimäki, 2003). Utilizing these technologies not only supply a platform to support multi-level and hierarchically integrated analysis on resource and environment, but also integrate the obtained information in a comparative theoretical ecosystem analysis. Meanwhile, Plummer (2000) argued that perspectives of combining ecological models and remotely sensed data would focus on the estimation of accuracy, the issues of spatial and temporal scale, and long-term comprehensive datasets.
Water shortage in arid and semi-arid regions and declining its availability to a crisis ...
Droughts in Wyoming’s future are unpredictable and uncertain; however, Richard Guldin of the Rocky Mountain Forest and Range Experiment Station in Fort Collins, Colorado, has made some predictions for the water situati...
On the heart (center) of California is a flat area with miles and miles of farms and up to 230 different crops. The central valley agriculture is essential to the United States; it not only delivers almost half of the produce but also helps the economy by also giving more job opportunities (California Department of food and agriculture, 2014). Many families depend on the central valley agriculture to survive economically in the United States. It is a well-known fact that rain and snows in the Sierra Nevada Mountains are a very important element in the central valley. No rain in the central valley can cause many devastating issues to occur quickly. Recently in the year of 2013 California received less rainfall than years before. The small amount of water the central valley is receiving is harming not only to the land but humans and animals as well. It’s destroying the habitats of animals with forest fires caused from the dry spells occurring. The central valley is going through a drought, so much that around this time of year the central valley usually accumulates enough rain for the necessities in the valley, agriculture for example. This year, however, has been different, the central valley hasn’t received enough water and this has caused a drought in the valley. Water is an important element in this world for not only human life, but for the environment in general, a shortage of water supply can bring issues to the environment and those living in it. The central valley holds the largest percent of class one soil, not only that, the valley grows a third of all the produce being grown in the United States, that’s more than 230 crops that are being grown in the central valley. However, this drought isn’t only affecting the resident...
Extreme weather events, such as drought, are tremendously important when considering stressors to water resources. History of drought has been documented in Paleoclimate studies using long lived tree species indigenous to Texas. Tree-ring proxies are especially useful when reconstructing histories of climate change across a large region like Texas, since many can be sampled from different areas. Annual tree ring data can give a precise year-to-year temperature and precipitation records. Tree ring data has shown droughts lasting a decade or more staggered throughout the state happening randomly since the 1600’s. (why this is important to water supply) [Brenner]
The following is a report on Australian drought situation. It will identity the definition of the drought, describe the causes of drought, represent impact of drought in Queensland and introduce management to help farmers cope with future drought occurrences.
Flooding is an extreme climatic event that generates devastation and economic losses all around the world. The extreme climatic events are increasing more severe and frequent due to the climate change. The climate change is a global scale, the mean annual surface temperature has increased over the past century by 0.6°C (IPCC, 2007).Climate models and theoretical arguments further indicate that extreme precipitation events will continue to increase with rises in greenhouse gas (GHG) concentrations (Min et al., 2011). Climate change will have significant impacts on precipitation patterns, overall increase in annual average temperature, increase precipitation of frequency, magnitude, precipitation amounts, severe events and flooding risk. The frequency, magnitude and severity of flooding are also increasing in many parts of the world associated with climate change, population pressure and urbanization (Hirabayashi et al., 2013., Jongman et al., 2014). These increases in the frequency and severity of extreme precipitation, impact of climate change associated damages and losses from flooding, is also likely to increase in the 21st century and beyond (Allamano et al., 2009; Pallet al., 2011).
The environmental data consist of monthly normalized difference vegetation index (NDVI), an average monthly temperature of local weather station, and the winter index. The NDVI demonstrate an approximation of ecological condition between regions and years. By calculating the average of different weather stations and take the mean of each of the month of spring, an overall provincial temperatures for the months can be calculated. This was necessarily due to...
The amount of water has been shrinking steadily but with extreme increases in population growth and consumption rate, countries in dry areas specifically the Middle East will feel the colossal effects of a water shortage. Since 1950, the population of the Middle East has risen by 21% a...
Due to geography and population growth, the Middle East nations are faced with a growing demand for a shrinking water supply. Throughout most of the Middle East region rainfall is irregular and the rainy season is very short. The World Bank reports that this area (including North Africa) has 5% of the world’s population, but only 1% of the world’s water. Droughts have been occurring more frequently and lasting longer, warning of a bleaker future.
The rise in temperature is having a significant impact on levels of rainfall, which in turn effects water run-off. Satellite observations since 1987 have shown that, as global temperatures have increased, global mean precipitation has increased in parallel at a rate of 7.4 ± 2.6% per ◦C ...
The states in the American Southwest have been caught in a consistent drought for years now. The population in these areas, especially California, used to be much lower but the population has rapidly increased in the last fifty years. Freshwater is something that everyone uses daily, and unfortunately, this is becoming a limited resource in the southwest area. Due to the ongoing drought, areas such as California and Palm Springs have ordered water cuts to try and reduce the overall amount of water being used. The “California Dream” used to be a way of living in a dry climate with long showers and luxurious lawns but is now being changed to a different dream where shower time has to be cut back and the luscious green plants are changed to native plants. The same thing has happened in Palm Springs, which used to be known as the “Desert Oasis” where the warm climate and surrounding greenery attracted populations
Drought is a phenomenon that has become characterizes a majority of Australia’s climate. It can be detrimental to the population of Australia especially on agricultural productivity. Within the region of drought southeastern Australia there are three main occurrences that cause drought, El Niño Southern oscillation, Indian Ocean dipole and variability and the Southern annular mode. Since drought in Australia can become so severe, the federal government has accepted drought as a feature of the climate and has emergency funding for those affected in times of ‘exceptional circumstances’ (textbook).
One resource that thoroughly explains the effects of a drought are websites and these couple of websites were very thorough in their explanation of the causes and effects of droughts.
Who is more important? Farmers or water regulations in California? The drought in California has been unbearable, especially with farmers pumping and stealing ground water. Since of this drought, many farmers have become desperate and are stealing a great deal of water from many cities and neighbors, leaving a majority of people without water. The government wants to enact water regulations to where water can be dispersed and used equally. With these new laws, the population can enjoy having running water without the fear of it ceasing to function.
Meteorological drought is referred as a precipitation deficiency, in comparison to normal or base line condition. We use Standardized Precipitation index (SPI-n, where n = 3, 6, 9 and 12 months accumulation period) as an index of meteorological drought. SPI represents a statistical z-score or the number of standard deviations (following a probability distribution, usually Gamma and back transformed to standard normal distribution) above or below that an event is from the mean (McKee et al. 1993; Sims et al., 2002). SPI is spatially invariant and probabilistic in nature and able to capture different drought states ranging from short, medium and long-term drought conditions depending on the length of the accumulation period. SPI has number of advantages, such as (Lloyd-Hughes and Saunders, 2002); (i) The SPI is based on precipitation and requires computation of only two