Practical Utility

The dangers to the natural resource base, crops, and livestock that have a meteorological component include pollution of soil and air soil erosion from wind or water the incidence and effects of drought crop growth animal production the incidence and extent of pests and diseases the inci dence, frequency, and extent of frost the dangers of forest or bush fires losses during storage and transport and all farm operations. Agrometeo-rology offers practical solutions for harnessing climate...

Drought Exceptional Circumstances

Drought conditions of some magnitude are present almost every year in some part of Australia because of its vast size and semiarid to arid climate. Such occurrences are a part of normal life and are not of major concern at the national level. Sustained droughts, usually lasting one to two years, possibly for three years, and extending across large tracts of the country have created great disasters. These are of relatively less frequent occurrence, and each of them has different spatial,...

Meteorological Indicators Of Drought

Drought conditions are basically due to a deficit of water supply in time and or space. The deficit may be in precipitation, stream flow, or accumulated water in storage reservoirs, ground aquifers, and soil moisture reserves. In describing a drought situation, it is important to understand its duration, spatial extent, severity, initiation, and termination. Depending on the areal extent, a drought can be referred to as a point drought, small-area drought, or a continental drought. The point...

Nature And Laws Of Radiation

The behavior of electromagnetic radiation may be summed up in the following simplified statements Every item of matter with a temperature above absolute zero emits radiation. Substances that emit the maximum amount of radiation in all wavelengths are known as black bodies. Such bodies will absorb all radiation incident upon them. A black body is thus a perfect radiator and absorber. Substances absorb radiation of wavelengths, which they can emit. The wavelengths at which energy is emitted by...

Chapter

Ballestra, G., Bertozzi, R., Buscaroli, A., Gherardi, M., and Vianello, G. (1996). Applicazioni dei Sistemi Informativi Geografici nella Valutazione delle Modifi-cazioni Ambientali e Territoriali. (Application of geographic information system for evaluating environmental and infrastructural modifications.) Milano, Italy Franco Angeli. Bierwirth, P.N. and McVicar, T.R. (1998). Rapid Monitoring and Assessment of Drought in Papua New Guinea Using Satellite Imagery. Port Moresby, Papua New Guinea...

Simulation Models Relevant To Australian Farming Systems

During the twentieth century, world agriculture passed through three revolutionary eras. The first was the mechanical (1930-1950), the second, seed-fertilizer (1960-1970), and the third, information technology (in the closing decades of the century). Within the span of the last two decades of the century, several thousand computer-based plant and animal dynamical models were developed worldwide which have expanded scientific insight into the complex interactions between environmental and...

Making Effective Use Of Rainfall

An inadequate and variable water supply and extremes of temperatures are the two universal environmental risks in agricultural production. High temperatures in tropical climates limit the production of crops native to temperate latitudes, and low winter temperatures in high latitudes are a check on growing crops native to tropical areas. Inadequate and variable water supply, however, has a negative impact on crop production in every climatic region. The problem is more pronounced in tropical...

Remote Sensing

Remote sensing is defined as the science of obtaining and interpreting information from a distance, using sensors that are not in physical contact with the object being observed. Animals (including people) use remote sensing via a variety of body components to obtain information about their environment. The eyes detect electromagnetic energy in the form of visible light. The ears detect acoustic (sound) energy, and the nose contains sensitive chemical receptors that respond to minute amounts of...

Definition Of Drought

The definition of drought is not very simple, and the question What is drought continues to pose a problem (Sivakumar, 1991). This is because drought could mean different things to different people, and there are probably as many definitions of drought as there are users of water. In general, a drought is when a shortfall in precipitation creates a shortage of water, whether it is for crops, utilities, municipal water supply, recreation, wildlife, or other purposes. According to a WMO...

Impact Of Climate Change On Hydrology And Water Resources

One of the major impacts of global warming is likely to be on hydrology and water resources, which in turn will have a significant impact across many sectors of the economy, society, and environment (Figures 11.2 and 11.3). Characteristics of many ecosystems are heavily influenced by water availability. Water is fundamental for human life and many activities, in- FIGURE 11.2. Impact of climate change on water resources and agriculture FIGURE 11.2. Impact of climate change on water resources and...