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Drought monitoring is an important process for national agricultural and environmental planning. Droughts are normal recurring climatic phenomena that affect people and landscapes. They occur at different scales (locally, regionally, and nationally), and for periods of time ranging from weeks to decades. In Zimbabwe drought is increasingly becoming an annual phenomenon, with varying parts of the country being affected. The purpose of this paper is to analyse the spatial variations in the seasonal occurrences of drought in Zimbabwe over a period of five years.

The Vegetation Condition Index (VCI), which shows how close the Normalized Difference Vegetation Index of the current time is to the minimum Normalized Difference Vegetation Index calculated from the long-term record for that given time, was used to monitor drought occurrence in Zimbabwe. A time series of dekadal Normalized Difference Vegetation Index, calculated from SPOT images, was used to compute seasonal VCI maps from 2005 to 2010. The VCI maps were then classified into three drought severity classes (severe, moderate, and mild) based on the relative changes in the vegetation condition from extremely bad to optimal.

The results showed that droughts occur annually in Zimbabwe though, on average, the droughts are mostly mild. The occurrence and the spatial distribution of drought in Zimbabwe was also found to be random affecting different places from season to season thus the authors conclude that most parts of the country are drought prone.

Remote sensing technologies utilising such indices as the VCI can be used for drought monitoring in Zimbabwe.

The remote sensing data have become the irreplaceable source of data for the regions with little or without rainfall data, but these data also require scientific analysis, correction and application. This paper uses FY-2 rainfall data and the case studies of the droughts occurred in the Weihe River Basin from 2006 to 2009 to monitor the spatial and temporal evolution of climatic droughts. The monitoring results indicate that: (1) Except for 2008 which was a dry year, the other years in the Weihe River Basin had normal dry/wet conditions; (2) From October 2008 to January 2009, the rainfall was significantly reduced across the Weihe River Basin, and the continual rainfall was even less than 1 mm for December and January with a precipitation anomaly percentage lower than -80%, a sign of severe climatic drought. But the rainfall has improved since February 2009, when the precipitation reached 17.8 mm and Pa exceeded 100%, which helped to relieve the stress from drought resistance. A heavy precipitation continued for four months from June to September 2008, with the Pa exceeding 50%; (3) Due to the better temporal and spatial continuity than the ground-based meteorological observation, FY-2 precipitation data have good application prospects in the meteorological drought monitoring at a national or regional macro-scale.

The purpose of this paper is to identify drought conditions in Jordan in the period 1960‐2006 for two major basins – the Yarmouk and the Zarqa. This study aims to look at the long‐term drought conditions (hydrological droughts) and to investigate the possibility of changes in the monthly precipitation pattern for the period of 1997‐2006, as this period has suffered from the average slightly dry conditions for the two basins.

The Standard Precipitation Index (SPI) is used to assess drought conditions in the Yarmouk and Zarqa basins. The SPI is applied on an annual basis to assess the hydrological long‐term droughts. Average monthly precipitation is used as the input to the SPI procedure.

The SPI is applied on an annual basis (12 months) SPI‐12. Results of the SPI‐12 assessment show that the years 1978, 1995, and 1999 represented extremely dry conditions in both basins. The years 1989 and 1993 represented severely dry conditions in the Zarqa basin and extremely dry conditions in the Yarmouk basin. The statistical procedure for precipitation anomalies identifies precipitation anomalies for the years 2000, 2003, and 2006. However, due to the limited number of anomaly years this study does not conclude that there is a change in the pattern of monthly precipitation of the tested period 1997‐ 2006.

Using the SPI method this work can be extended to compare drought conditions in the remaining major basins in the country.

The paper provides important information about drought conditions in Jordan and ways to assess precipitation anomalies and pattern changes. This can be beneficial to the planning of water resources in Jordan and the associated developments (agricultural, industrial, tourism, and residential).

Case studies from many countries indicate that even when rainfall is high drought can still occur. Droughts have been recorded in Bangladesh, where the rainfall is 2,300mm per year, and in Luang Prabang, Laos, where the annual rainfall is 3,200mm. Similarly, the highest Standardized Precipitation Index (SPI) value of 2.78 indicates a possibility of floods in Cambodia. Identification of a threshold SPI value is necessary to pinpoint impending drought. Since SPI values reflect only the rainfall situation and not the existing water availability in reservoirs and canal systems, such a detailed impact-assessment study should also compare the duration of a negative SPI value with that of reduction in the available water from various sources, including groundwater, reservoirs, and canal irrigation systems. So drought occurs not only because of lack of rainfall but also because of bad practices of water usage and water management.

The Monsoon Asian region has a much wider rainfall distribution than other regions of the world. The countries in this region are characterized mostly by floods and typhoons, which result from the interplay among the ocean, the atmosphere, and the land. Thus, many factors affect the strength of the rainfall, including sea surface temperatures in the Indian and Pacific Oceans, variations in solar output, land snow cover and soil moisture over the Asian continent, and the position and strength of prevailing winds. The links between these factors and monsoons appear to wax and wane over time, and the observational record is too short to explain this longer-term variability. Precipitation and surface wind maps of Asia during the summer months of June to August show the average spatial patterns of monsoon circulation and moisture.

While Erratic Distribution of Monsoon is the main cause of abnormal monsoon, the consequences of Early Withdrawal of Monsoon are generally quite serious and can create disastrous situations for the drought-prone areas of the country. It is this intrinsic variability of the rainfall over India, in both time and space that makes India, especially the drier regions thereof, vulnerable to droughts. Although no part of India is immune to the adverse impacts of drought, the arid and ,semi-arid regions in the western, northern and peninsular parts of the country experience more frequent droughts, at times leading to a crippling impact on the national economy. The Indian economy, thus, has been described as a “gamble of monsoon” (Venkateswarlu, 2010). A look at the rainfall departure¹ and the corresponding food-grain production (Table 1) in India from 2000 to 2009 reveals that in the drought years of 2002 and 2009 the All India rainfall departure was −19.2% and −21.8%, respectively, leading to a drastic fall in food-grain production by 13.4 and 6.9%, respectively, as compared to the previous years, which received good monsoon rains.

This research paper is informed by a study to assess performance of local knowledge drought forecasts (LKDFs) in the Mzingwane catchment which is located in the Limpopo River Basin in Zimbabwe. The purpose of this paper is to validate local traditional knowledge (LTK) indicators being applied in Mzingwane catchment and verify their accuracy and reliability in drought forecasting and early warning.

LTK forecast data for 2012/2013 season were collected through structured questionnaires administered to 40 selected household heads and focus group discussions. Observations and key informant interviews with chiefs and the elderly (>55 years) were also used to collect additional LTK forecast data. Meteorological data on seasonal rainfall were collected from the meteorological Services Department of Zimbabwe (MSD). Two sets of comparisons were conducted namely the hind-cast comparison where the LKDF system results were evaluated against what the season turned out to be and forecast comparison where local LKDF system results were compared with downscaled meteorological forecasts.

The results showed that the majority of the LTK indicators used were accurate in forecasting weather and drought conditions when compared to the observed data of what the season turned out to be. LTK forecasts were found to be more accurate than meteorological forecast at local scale. This study has shown that the reliability of LTKs is high as demonstrated by the fact that the predicted event occurs.

Further validation be carried out for a number of seasons, in order to standardise the LTK indicators per geographical area.

The research creates platform for adoption of LTKs into formal forecasting systems. The research is useful to both meteorological researchers and resource constrained communities in Mzingwane catchment.

The purpose of this paper is to investigate the patterns and trends of drought incidence in north east highlands of Ethiopia using monthly rainfall record for the period 1984-2014.

Standard precipitation index and Mann – Kendal test were used to analyze drought incident and trends of drought occurrences, respectively. The spatial extent of droughts in the study area has been interpolated by inverse distance weighted method using the spatial analyst tool of ArcGIS.

Most of the studied stations experienced drought episodes in 1984, 1987/1988, 1992/1993, 1999, 2003/2004 and 2007/2008 which were among the worst drought years in the history of Ethiopia. The year 1984 was the most drastic and distinct-wide extreme drought episode in all studied stations. The Mann–Kendal test shows an increasing tendencies of drought at three-month (spring) timescale at all stations though significant (p < 0.05) only at Mekaneselam and decreasing tendencies at three-month (summer) and 12-month timescales at all stations. The frequency of total drought was the highest in central and north parts of the region in all study seasons.

This detail drought characterization can be used as bench mark to take comprehensive drought management measures such as early warning system, preparation and contingency planning, climate change adaptation programs.

In many parts of the globe, drought is becoming frequent and severe. Drought is related to water and for that reason, this chapter begins by describing the movement of water on planet earth. In a second phase, the drought concept is defined and the different types of drought are identified. At the end, the impacts and the relationship between climate change and drought are described.

Examine the usability of rainfall and temperature outputs of a regional climate model (RCM) and meteorological drought indices to develop a macro-level risk transfer product to compensate the government of Central Java, Indonesia, for drought-related disaster payments to rice farmers.

Based on 0.5° gridded rainfall and temperature data (1960–2015) and projections of the WRF-RCM (2016–2040), the Standardized Precipitation Index (SPI) and the Standardized Precipitation Evapotranspiration Index (SPEI) are calculated for Central Java over different time spans. The drought indices are correlated to annual and seasonal rice production, based on which a weather index insurance structure is developed.

The six-month SPI correlates best with the wet season rice production, which generates most output in Central Java. The SPI time series reveals that drought severity increases in future years (2016–2040) and leads to higher payouts from the weather index structure compared to the historical period (1960–2015).

The developed methodology in using SPI for historical and projected periods allows the development of weather index insurance in other regions which have a clear link between rainfall deficit and agricultural production volatility.

Meteorological drought indices are a viable alternative for weather index insurance, which is usually based on rainfall amounts. RCM outputs provide valuable insights into future climate variability and drought risk and prolong the time series, which should result in more robust weather index insurance products.