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Meteorological Drought Module
This module consists of menus, such as IMD-Table, IMD-Map, Drought86 and Drought99, which consist of results of meteorological drought analysis performed for two basins. Twenty-nine years monthly rainfall data were analysed and drought severity class namely no drought, mild, moderate, and severe was determined by IMD method for each station from 1971 to 1999. The above results in the form of table can be accessed and updated by invoking a menu named IMD-Table of this module. A map comprising blocks of the basin linked with IMD results so that the yearly drought severity classes can be retrieved from the IMD-Map menu. From the above results blockwise drought severity maps can be plotted for any year. Drought severity maps for the years 1986 and 1999, which are highly drought affected, were plotted. The above maps can be accessed from the Drought86 and Drought99 menus, which depict the drought status in the basin.

Hydrological Drought Module
Hydrological drought module consists of surface water and ground water menus within which submenus with relevant information are incorporated.

Surface water drought
Surface water menu consists of submenus such as SW-Table, SW-Graph, SW-Map that show the results of hydrological drought analysis. Thirty years of irrigation release data of anicuts and reservoirs of the two basins were analysed. Using Herbst method, onset, termination and intensity of dry spells were determined. A map consisting of anicuts and reservoirs linked with the above results as attributes can be accessed from SW-Map menu. Drought results in tabular format can be retrieved and updated from the SW-Table menu. From SW-Graph menu, graph depicting the monthly flow, mean monthly flow, drought severity can be accessed and updated without any difficulty.

Ground water drought
Ground water component menu consist of submenus such as GWD-Map, GWD-Table, GWD-Graph,. GWDI-Ma p. Using Herbst method, from 29 years water level data of the study basins, onset, termination and intensity of ground water dry spells were determined. The above results in tabular format can be retrieved and updated from GWD-Table menu. GWD-Graph menu depicts the graphical representation of monthly water level, mean monthly water level, drought severity, which can be retrieved and updated without any difficulty. The characteristics of dry spells such as duration and intensity were attached as attributes to the Well map that can be accessed from GWD-Map menu. Attribute data of wells can be viewed by querying the respective wells. Interpolating the intensity of dry spell values over the basin, a map depicting the variation of ground water drought intensity during the most drought affected years were plotted. The above maps which could be retrieved from the GWDI-Map menu.

Agricultural Drought Module
This module consists of menus namely Rainfall, Vegetation status, Agridrought, and Crop area. In the agricultural context, crop seasonal drought analysis can be performed using remote sensing data. Rainfall data were analysed to select the recent normal year. The vegetation status during the drought year was compared with normal year to assess the agricultural drought. In this study, the recent years 1998 and 1999 vegetation statuses were analysed.

Normal year and deficit year rainfall distribution map of 1998 and 1999 were plotted and analysed for both the study basins and retrieved through the Rainfall menu. NDVI analysis was performed using WiFS data of IRS 1C and 1D to plot the vegetation status map that can be obtained through Vegetation status map. Crop area map of 1998 and 1999 were plotted using the above data and retrieved through Crop area menu. Block wise agricultural drought severity maps were developed by NDVI statistics. AgriDS Map menu can be invoked to access the above maps.

Drought Risk Area Module
This module consists of menus namely Meteorological drought risk, Hydrological drought risk, Supply oriented drought risk and Land based Integrated drought risk menus within which the submenus are present which can be invoked using mouse to access the relevant drought risk information. For effective drought proofing, vulnerable areas have to be identified accurately. Moreover, the drought proofing works may be made as per the nature of drought such as meteorological, hydrological and agriculture. Each context of drought was analysed separately and risk maps were plotted which were incorporated in this module. Combining the meteorological and hydrological drought aspects, supply oriented drought risk map was plotted which is presented in this module. Integrating the above Supply oriented drought risk and Landuse, Land based integrated drought risk map was plotted which is also presented in this module.

Meteorological drought risk
As far as meteorological drought is concerned, frequency analysis was performed using twenty-nine years rainfall data and a meteorological drought risk index was developed for each rainfall station. Interpolating the above index by Natural neighbourhood method, using vertical mapper, meteorological drought risk area map was plotted and presented in this module.

Meteorological drought risk menu consists of submenus such as Met risk table Index map and Risk map. The sub menu named Met risk table consisting of risk index values, drought severity class for each station, which can be accessed and updated by invoking the menu using mouse. A layer consists of all thirty five raingauge stations along with attribute data of risk index values and drought severity class is incorporated in the sub menu named Index map which can be accessed by clicking the raingauge station in the map. From the sub menu named risk map the meteorological drought risk index map, can be accessed. From this map, pockets or parts of a block, prone to meteorological drought can be identified and suitable drought proofing measures may be taken.

Hydrological drought risk
Hydrologic drought risk menu consists of surface water risk and ground water risk sub components menus. Using 29 years irrigation release data of anicuts and reservoirs of the study basins, the drought duration and drought intensity were determined by Herbst method. Using drought duration and intensity obtained, surface water drought risk index was developed. Blocks benefited by each anicut were determined. Surface water risk menu consists of sub menus such as SW risk table, Index map and Risk map. Table containing risk index, command area and drought proneness can be accessed and updated from the SW risk table menu. A layer containing the anicuts and reservoirs linked with risk index values and drought severity class can be viewed by invoking the Index map submenu. Surface water drought risk indices were assigned to respective blocks and surface water risk area map was plotted which could be accessed from submenu named Risk map.

Supply oriented drought risk
Supply oriented drought risk menu consists of submenus such as Supply risk table, Index map and Risk map. The individual risk maps give the idea to perform some specific drought proofing works. However, drought risk status in all aspects is needed to prioritise the areas of the basins for taking up the relief measures. Supply oriented drought risk index was developed by combining the meteorological, surface and ground water drought risk indices of each block and classified into four categories namely very mild, mild, moderate and severe. Supply risk table menu contains the risk index values and drought severity class which can be retrieved and updated. A map consisting all blocks was attached with the risk values and severity class can be accessed by invoking the Index map submenu. The map showing the spatial distribution of supply oriented drought risk can be accessed from the submenu named Risk map.