Physical Sciences and Mathematics Commons^™

Food Security In The Southern African Development Community States, Joshua Chigodora

Drought Network News (1994-2001)

The 1995–96 cereal harvest in the Southern African Development Community (SADC) is the best within the last ten years. Provisional assessments project a regional maize surplus of 2.08 million tons, a 72% increase in production over the previous year’s harvest. Overall cereal production substantially increased in all countries except Tanzania, where the current cereal forecast of 3.73 million tons is a 14% drop from last year’s output of 4.34 million tons. Of special note are the exceptionally large increases in the area planted in cereals in war-ravaged Angola and Mozambique, for the first time in many years. Production trebled in …

Moisture Deficit Index Evaluated For Dry Regions Of India, K. K. Nathan, S. K. Sinha

Drought Network News (1994-2001)

In India, about 70% of the cultivable land is rainfed. This includes areas where crops are rarely affected by drought and areas where crops experience moisture stress and often fail. The regions with the latter characteristics are often called dryland areas and the agriculture so practiced there is known as dryland agriculture. About 35% of the total cultivable land belongs in this category. To determine the magnitude of water deficiency in these regions, the moisture deficit index (MDI) has been evaluated for dryland stations in India. The MDI is usually determined on the basis of annual precipitation and annual potential …

Exploring The Potential For Using Enso Forecasts In The U.S. Corn Belt, Jennifer G. Phillips, Cynthia Rosenzweig, Mark Cane

Drought Network News (1994-2001)

Interannual climate variability poses the greatest risk that farmers face. Until recently, seasonal climate forecasts have been weak and therefore rarely observed by farmers in making management decisions. Farm management is generally based on long-term mean expectations of climate and crop responses to local edaphic conditions. Currently, significant progress is being made in the skill level of predictions of seasonal to interannual climate, primarily because of new understanding of the teleconnections between ocean circulation and atmospheric processes. The El Niño/Southern Oscillation (ENSO) refers to fluctuations in both sea-surface temperatures (SSTs) in the eastern equatorial Pacific and in sea-level pressures in …

Meteorological Drought In Turkey: A Historical Perspective, 1930-–93, Murat Türkes

Drought Network News (1994-2001)

The climate of Turkey, which is mainly characterized by the Mediterranean macro climate, results from the seasonal alternation of frontal depressions with polar air masses and subtropical high pressures with subsiding maritime tropical and continental tropical air masses. Continental tropical airstreams from the northern African and Arabian deserts particularly dominate throughout the summer, by causing long-lasting warm (hot) and dry conditions over Turkey (except the Black Sea region and northeastern Anatolia). Turkey has an area of 779,452 km² and an average elevation of 1,132 m.

This study outlines some spatial and temporal characteristics of Turkey’s rainfall, particularly in terms …

Assessing The Impacts Of El Niño And Non-El Niño-Related Droughts Over India, R. H. Kripalani, Ashwini Kulkarni

Drought Network News (1994-2001)

It has now been recognized that the single most important key to the earth’s year-to-year climate variability is the El Niño/Southern Oscillation (ENSO) phenomenon. El Niño episodes directly affect the climate of at least half the planet and in many instances result in heavy loss of life and resources. The global impacts of El Niño events have been summarized in a review article by Bigg (1990), while the role of ENSO in Indian monsoon rainfall variability is given in Krishna Kumar et al. (1995). During the ENSO warm/ cold extremes—i.e., El Niño/La Niña events—the majority of the episodes induce below/above-normal …

A Prototype National Drought Alert Strategic Information System For Australia, Ken D. Brook, John O. Carter

Drought Network News (1994-2001)

Defining and categorizing drought in a quantitative and scientific manner are important national issues for Australian state and Commonwealth governments, landholders, and agribusiness. The challenge for modelers of Australia’s grasslands is to integrate biological models, geographic information systems (GIS), satellite imagery, economics, climatology, and visual high-performance computing into an Internet-deliverable application that can provide easily understood monitoring and prediction advice in near real-time— a national drought alert strategic information system.

Although NOAA satellite-derived imagery has been somewhat useful in the broad-scale spatial assessment of green cover, especially the spatial response of vegetation to rainfall events (Smith, 1994; Dudgeon et al., …

Drought Continues In Hungary In 1995, Attila Bussay, Csaba Szinell

Drought Network News (1994-2001)

In 1995, Hungary again suffered from serious drought. Fortunately, drought has not extended over the whole country. It is primarily centered in the southeast, a plain area with significant agricultural production.

Meteorological conditions have been the most important factors in the evolution of the drought. The start of 1995 was not ideal; dry conditions during 1994 resulted in poor soil moisture at the beginning of the season. In Figure 1, the water shortage is indicated using the Palmer Drought Severity Index (PDSI), revealing the extraordinarily dry winter conditions in the east.

Changes In Drought Policies In New Zealand, Heather J. Keen, Lynmore Rotorua

Drought Network News (1994-2001)

New Zealand, lying in the South Pacific Ocean approximately 1,200 miles east of Australia, is subject to recurring droughts. Its two main islands are long and narrow, with high mountain ranges and hill country bisecting them from north to south. The predominant westerly winds, along with the mountain ranges and hill country, produce a marked orographic effect. Thus, the western side of the country, in general, records significantly higher annual average rainfall totals than does land on the eastern side.

The country has experienced a number of severe droughts throughout its history, especially in the east, where a number of …

Recent Advances In Seasonal Forecasting In Southern Africa, Leonard S. Uganai

Drought Network News (1994-2001)

Climatic uncertainty posed by the looming possibility of unprecedented climatic change is presenting society with new challenges the world over. In recent years, demand for long-range seasonal to interannual climate forecasts has been on the rise as society grapples with climatic risk management in southern Africa. Although more investment is still required to bring weather services in the region to a level advanced enough to handle the emerging complex and economically justified user needs for climatic services and products, some commendable progress has already been made, particularly in providing seasonal forecasts in addition to the other traditional core services and …

Effects Of Water Stress On Soybean Productivity In Central India, Ajay K. Srivastava, Diwakar Naidu, A. S. R. A. S. Sastri, J. S. Urkurkar, B. Das Gupta

Drought Network News (1994-2001)

In the Chhattisgarh plains in the agroclimatic region of central India (Figure 1), farms may be characterized by one of the following: unbunded lathyritic soils, bunded rice fields (rainfed), bunded rice fields (irrigated), unbunded black soils, or rice bunds. Under these five farming situations, different crop sequences have been in vogue. New crops and crop sequences are recommended by the Agricultural University from time to time based on experimental results.

In the unbunded black soils, farmers usually plant small millets and pigeon pea. However, based on experimental results, the University has recommended soybean followed by chickpea crop sequence under rainfed …

Drought Preparedness And Management Training Seminar Conducted For West Africa

Drought Network News (1994-2001)

All of the World Meteorological Organization (WMO) member countries of western Africa were represented at a seminar conducted in Banjul, The Gambia, 4–9 September 1995. The Training Seminar on Drought Preparedness and Management for Western Africa was conducted to improve awareness of drought and appropriate mitigation and preparedness technologies to reduce impacts. The seminar was organized by WMO and sponsored by WMO and the UN Sudano-Sahelian Office.

Climatic And Hydrologic Oscillations In The Owens Lake Basin And Adjacent Sierra Nevada, California, Larry Benson, James W. Burdett, Michaele Kashgarian, Steve Lund, Fred Phillips, Robert O. Rye

United States Geological Survey: Staff Publications

Oxygen isotope and total inorganic carbon values of cored sediments from the Owens Lake basin, California, indicate that Owens Lake overflowed most of the time between 52,500 and 12,500 carbon-14 (¹⁴C) years before present (B.P.). Owens Lake desicated during or after Heinrich event H1 and was hydrologically closed during Heinrich event H2. The magnetic susceptibility and organiz carbon content of cored sediments indicate that about 19 Sierra Nevada glaciations occurred between 52,500 and 23,500 ¹⁴C years B.P.

Origin Of The Late Quaternary Dune Fields Of Northeastern Colorado, Daniel R. Muhs, Thomas W. Stafford, Scott D. Cowherd, Shannon A. Mahan, Rolf Kihl, Paula B. Maat, Charles A. Bush, Jennifer Nehring

United States Geological Survey: Staff Publications

Stabilized eolian deposits, mostly parabolic dunes and sand sheets, cover much of the landscape of northeastern Colorado and adjacent parts of southwestern Nebraska in four geographically distinct dune fields. Stratigraphic and soil-geomorphic relations and accelerator radiocarbon dating indicate that at least three episodes of eolian sand movement occurred between 27 ka and 11 ka. possibly between 11 ka and 4 ka. and within the past 1.5 ka. Thus, eolian sand deposition took place under both glacial and interglacial climatic conditions. In the youngest episodes of eolian sand movement. Holocene parabolic dunes partially buried Pleistocene sand sheet deposits.

Late Holocene sands …