Heman Abdulkhaleq A. Gaznayee started out his academic career in Agriculture science(plant production) in 2003-2004, He graduated with his BSc in plant production. He acquires his master's degree in 2007 in the field of plant production(Plant Production) where he has currently completed his Ph. D in Drought with a focus on GIS and Remote sensing. A substantial focus of Heman's work is on the Drought areas mapping to improve environmental outcomes and enhance planning capabilities.
To increase agricultural productivity and ensure food security, it is important to understand the... more To increase agricultural productivity and ensure food security, it is important to understand the reasons for variations in irrigation over time. However, researchers often avoid investigating water productivity due to data availability challenges. This study aimed to assess the performance of the irrigation system for winter wheat crops using a high-resolution satellite, Sentinel 2 A/B, combined with meteorological data and Google Earth Engine (GEE)-based remote sensing techniques. The study area is located north of Erbil city in the Kurdistan region of Iraq (KRI) and consists of 143 farmer-owned center pivots. This study also aimed to analyze the spatiotemporal variation of key variables (Normalized Difference Moisture Index (NDMI), Normalized Difference Vegetation Index (NDVI), Precipitation (mm), Evapotranspiration (ETo), Crop evapotranspiration (ETc), and Irrigation (Hours), during the wheat-growing winter season in the drought year 2021 to understand the reasons for the varian...
In the past two decades, severe drought has been a recurrent problem in Iraq due in part to clima... more In the past two decades, severe drought has been a recurrent problem in Iraq due in part to climate change. Additionally, the catastrophic drop in the discharge of the Tigris and Euphrates rivers and their tributaries has aggravated the drought situation in Iraq, which was formerly one of the most water-rich nations in the Middle East. The Kurdistan Region of Iraq (KRI) also has catastrophic drought conditions. This study analyzed a Landsat time-series dataset from 1998 to 2021 to determine the drought severity status in the KRI. The Modified Soil-Adjusted Vegetation Index (MSAVI2) and Normalized Difference Water Index (NDWI) were used as spectral-based drought indices to evaluate the severity of the drought and study the changes in vegetative cover, water bodies, and precipitation. The Standardized Precipitation Index (SPI) and the Spatial Coefficient of Variation (CV) were used as meteorologically based drought indices. According to this study, the study area had precipitation def...
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Drought is a common event in Iraq’s climate, and the country has severely suffered from drought e... more Drought is a common event in Iraq’s climate, and the country has severely suffered from drought episodes in the last two decades. The Kurdistan Region of Iraq (KRI) is geographically situated in the semi-arid zone in Iraq, whose water resources have been limited in the last decades and mostly shared with other neighboring countries. To analyze drought impacts on the vegetation cover and the land surface temperature in the KRI for a span of 20 years from 1998 to 2017, remote sensing (RS) and Geographical Information Systems (GIS) have been adopted in this study. For this study, 120 Landsat satellite images were downloaded and utilized, whereas six images covering the entire study area were used for each year of the study period. The Normalized Difference Vegetation Index (NDVI) and Land Surfaces Temperature Index (LST) were applied to produce multi-temporal classified drought maps. Changes in the area and values of the classified NDVI and LST were calculated and mapped. Mann–Kendall ...
IOP Conference Series: Earth and Environmental Science, 2021
Drought is a natural hazard that significantly impacts economic, agricultural, environmental, and... more Drought is a natural hazard that significantly impacts economic, agricultural, environmental, and social aspects and is characteristic of Iraq’s climate, particularly the Iraqi Kurdistan Region (IKR). For studying the spatiotemporal characteristics of drought severity in the IKR, a time-series of 120 Landsat images (TM, 7 ETM+, and OLI sensors) over twenty years (1998-2017) was assembled. Twenty separate mosaics of six Landsat scenes were used to derive the Vegetation Condition Index (VCI). The VCI index was employed to capture the drought severity in the study area. Results revealed that 1999, 2000, and 2008 were the most severe drought years. The results also indicated that severe droughts increased by 29.1%, 25.0%, and 26.9 through 1999, 2000, and 2008, respectively. Furthermore, a drop in precipitation averages occurred in the two years and significantly reduced the VCI values. Statistical analysis exhibited significant correlations between the VCI and each precipitation, and cr...
Drought is an extreme climate phenomenon that comprises climatic dubiety induced by the environme... more Drought is an extreme climate phenomenon that comprises climatic dubiety induced by the environment. Iraq experienced severely drought events in last decades, particularly Erbil Province in the Kurdistan Region. Over the last two decades, Erbil Province suffered from severe agricultural drought, causing a significant reduction in crop yield. The application of satellite-based indices for the assessment of drought severity assessment in semi-arid countries is well known. This study was sought to incorporate geoinformation technology into the evaluation of agricultural drought severity and its relationships with crop yield in Erbil Province throughout the years 1998-2017. Forty images of the Landsat satellites time-series 5 TM, 7 ETM+, and 8 OLI utilized for this study. Twenty mosaics of two scenes prepared to extract the MSAVI2 index. The results showed that the drought caused a reduction of crop yield, particularly in the years 2000, 2008, and 2012. Besides, a significant decline in the MSAVI2-based vegetation cover area by 22.3, 15.8, and 15.7% in the aforementioned years, respectively. The results also revealed significant relationships among the MSAVI2 values, vegetation area, rainfall, and crop yield. Whereas, it was (0.472*) between the MSAVI2 and rainfall, and (0.635**) between the MSAVI2 and crop yield. Furthermore, Erbil Province, suffered severe to exceptional agricultural drought episodes in its southern and western partsin the years 2000, 2008, and 2012. It can be concluded, that the MSAVI2 index is an efficient tool for evaluating the agriculture drought in Erbil Province, and its significant positive relationship with the crop yield is higher than the relationship with the rainfall.
Drought is a natural hazard that has a significant impact on the various aspects (i.e., economic,... more Drought is a natural hazard that has a significant impact on the various aspects (i.e., economic, agricultural, environmental, and social). This study was carried out to evaluate drought severity and frequency during the growing season (April month) in Duhok Governorate (DUG), the Iraqi Kurdistan Region (IKR), for the period from 1998 through 2012 based on Landsat-based spectral indices. In this study, 15 mosaics assembled for 15 years consist of two scenes of Landsat time series, in a total of 30 TM and ETM+ images (WRS2: 170/34 & 170/35) acquired in 1998 to 2012. Annual precipitation data were collected from 18 meteorological stations distributed in the (DUG) for the study period. Drought status was investigated using the Normalized Difference Vegetation Index (NDVI), Modified Soil Adjusted Vegetation Index (MSAVI2), and Normalized Difference Water Index (NDWI). The study results showed an increase in drought severity and frequency in the (DUG) during the fifty years, particularly...
Journal of Geoinformatics & Environmental Research
Spectral vegetation indices and their relations to some ecological and terrain variables in the I... more Spectral vegetation indices and their relations to some ecological and terrain variables in the Iraqi Kurdistan Region (IKR) is the main objective of this study. A mosaic of two Landsat-7 ETM+ images was utilized to produce five spectral vegetation indices, and Terra ASTER Digital Elevation Model (DEM) dataset were employed. The Normalized Difference Vegetation Index (NDVI), Soil Adjusted Vegetation Index (SAVI), Optimized Soil Adjusted Vegetation Index (OSAVI), Tasseled Cap Greenness, Land Surface Temperature (LST) were utilized for this study. The results of the current study revealed that MSAVI2 is more reliable and accurate in depicting the vegetation presence in the IKR, which is occupied 34.7% of the total study area in 2014. In terms of terrain variables, all vegetation indices responded to variation of aspect ratio variation. It was found that the densest vegetation exists between 180 to 350°. Mainly, in the South (157.5°-202.5°), Southwest (202.5°-247.5°), West (247.5°-292....
Journal of Advanced Research in Dynamical and Control Systems
Iraq, including Erbil Province in the Kurdistan region, has severely suffered drought events in t... more Iraq, including Erbil Province in the Kurdistan region, has severely suffered drought events in the past, particularly during the last two decades. This study incorporated Geoinformation technology into assessing and monitoring drought's severity and impacts that affected Erbil province in a span from 1998 to 2017. Twenty mosaics of two Landsat scenes for 20 years have accomplished for this study. Two spectral drought indices, the Normalized Difference Vegetation Index (NDVI) and the Temperature Condition Index (TCI), were extracted using 20 Landsat images mosaics to assess the drought's severity and impacts. Statistical correlation analyses computed between the NDVI, TCI, and the study variables, such as climatic factors, field crop area, and field crop yield. The study findings clarified that Erbil province experienced severe to extreme severe agricultural droughts, which caused significant reductions in crop yields, particularly in 2000, 2008, and 2012. The results also revealed significant declines in the vegetative cover in the years 2000, 2008 and 2012, by 43.8%, 16.3%, and 10.9%, respectively. Furthermore, a drop in precipitation averages has occurred in those three drought years, as well as a significant reduction in the TCI values. The study results clarified that the southern and western parts of Erbil Province were the most parts exposed to the severe to exceptional agricultural drought episodes throughout the twenty years of this study.
Drought was a severe recurring phenomenon in Iraq over the past two decades due to climate change... more Drought was a severe recurring phenomenon in Iraq over the past two decades due to climate change despite the fact that Iraq has been one of the most water-rich countries in the Middle East in the past. The Iraqi Kurdistan Region (IKR) is located in the north of Iraq, which has also suffered from extreme drought. In this study, the drought severity status in Sulaimaniyah Province, one of four provinces of the IKR, was investigated for the years from 1998 to 2017. Thus, Landsat time series dataset, including 40 images, were downloaded and used in this study. The Normalized Difference Vegetation Index (NDVI) and the Normalized Difference Water Index (NDWI) were utilized as spectral-based drought indices and the Standardized Precipitation Index (SPI) was employed as a meteorological-based drought index, to assess the drought severity and analyse the changes of vegetative cover and water bodies. The study area experienced precipitation deficiency and severe drought in 1999, 2000, 2008, 2009, and 2012. Study findings also revealed a drop in the vegetative cover by 33.3% in the year 2000. Furthermore, the most significant shrinkage in water bodies was observed in the Lake Darbandikhan (LDK), which lost 40.5% of its total surface area in 2009. The statistical analyses revealed that precipitation was significantly positively correlated with the SPI and the surface area of the LDK (correlation coefficients of 0.92 and 0.72, respectively). The relationship between SPI and NDVI-based vegetation cover was positive but not significant. Low precipitation did not always correspond to vegetative drought; the delay of the effect of precipitation on NDVI was one year.
Drought is a complex phenomenon that has severe impacts on the environment. Vegetation and its co... more Drought is a complex phenomenon that has severe impacts on the environment. Vegetation and its conditions are very sensitive to drought effects. This study aimed to monitor and assess the drought severity and its relationships to some ecological variables in ten districts of Erbil Governorate (Kurdistan Region), Iraq, throughout 20 years (1998-2017). The results revealed that droughts frequently hit Erbil throughout the study period. The Landsat time-series-based on Vegetation Condition Index (VCI) significantly correlated with precipitation, Digital Elevation Model (DEM), and latitude. Extreme VCI-based drought area percentages were
Drought is a complex phenomenon that has severe impacts on the environment. Vegetation and i... more Drought is a complex phenomenon that has severe impacts on the environment. Vegetation and its conditions are very sensitive to drought effects. This study aimed to monitor and assess the drought severity and its relationships to some ecological variables in ten districts of Erbil Governorate (Kurdistan Region), Iraq, throughout 20 years (1998-2017). The results revealed that droughts frequently hit Erbil throughout the study period. The Landsat time-series- based on Vegetation Condition Index (VCI) significantly correlated with precipitation, Digital Elevation Model (DEM), and latitude. Extreme VCI-based drought area percentages were recorded in 1999, 2000, 2008, and 2011 by 43.4%, 67.9%, 43.3%, and 40.0%, respectively. The highest crop yield reduction in the study area occurred mainly in 2000, 2008, and 2012 due to low precipitation rates. These results reveal the capability of the VCI for drought characteristics and highlighting relationships with some ecological variables, ...
IOP Conference Series: Earth and Environmental Science, 2021
Drought is a natural hazard that significantly impacts economic, agricultural, environmental, and... more Drought is a natural hazard that significantly impacts economic, agricultural, environmental, and social aspects and is characteristic of Iraq's climate, particularly the Iraqi Kurdistan Region (IKR). For studying the spatiotemporal characteristics of drought severity in the IKR, a time-series of 120 Landsat images (TM, ETM+, and OLI sensors) over twenty years (1998-2017) was assembled. Twenty separate mosaics of six Landsat scenes were used to derive the Vegetation Condition Index (VCI). The VCI index was employed to capture the drought severity in the study area. Results revealed that 1999, 2000, and 2008 were the most severe drought years. The results also indicated that severe droughts increased by 29.1%, 25.0%, and 26.9 through 1999, 2000, and 2008, respectively. Furthermore, a drop in precipitation averages occurred in the two years and significantly reduced the VCI values. Statistical analysis exhibited significant correlations between the VCI and each precipitation, and crop yield was 0.81 and 0.478, respectively. It can be concluded that the IKR experienced severe to extremely severe agricultural droughts, which caused significant reductions in crop yields, particularly in 2000 and 2008.
Drought was a severe recurring phenomenon in Iraq over the past two decades due to climate
change... more Drought was a severe recurring phenomenon in Iraq over the past two decades due to climate change despite the fact that Iraq has been one of the most water-rich countries in the Middle East in the past. The Iraqi Kurdistan Region (IKR) is located in the north of Iraq, which has also suffered from extreme drought. In this study, the drought severity status in Sulaimaniyah Province, one of four provinces of the IKR, was investigated for the years from 1998 to 2017. Thus, Landsat time series dataset, including 40 images, were downloaded and used in this study. The Normalized Difference Vegetation Index (NDVI) and the Normalized Difference Water Index (NDWI) were utilized as spectral-based drought indices and the Standardized Precipitation Index (SPI) was employed as a meteorological-based drought index, to assess the drought severity and analyse the changes of vegetative cover and water bodies. The study area experienced precipitation deficiency and severe drought in 1999, 2000, 2008, 2009, and 2012. Study findings also revealed a drop in the vegetative cover by 33.3% in the year 2000. Furthermore, the most significant shrinkage in water bodies was observed in the Lake Darbandikhan (LDK), which lost 40.5% of its total surface area in 2009. The statistical analyses revealed that precipitation was significantly positively correlated with the SPI and the surface area of the LDK (correlation coefficients of 0.92 and 0.72, respectively). The relationship between SPI and NDVI-based vegetation cover was positive but not significant. Low precipitation did not always correspond to vegetative drought; the delay of the effect of precipitation on NDVI was one year.
To increase agricultural productivity and ensure food security, it is important to understand the... more To increase agricultural productivity and ensure food security, it is important to understand the reasons for variations in irrigation over time. However, researchers often avoid investigating water productivity due to data availability challenges. This study aimed to assess the performance of the irrigation system for winter wheat crops using a high-resolution satellite, Sentinel 2 A/B, combined with meteorological data and Google Earth Engine (GEE)-based remote sensing techniques. The study area is located north of Erbil city in the Kurdistan region of Iraq (KRI) and consists of 143 farmer-owned center pivots. This study also aimed to analyze the spatiotemporal variation of key variables (Normalized Difference Moisture Index (NDMI), Normalized Difference Vegetation Index (NDVI), Precipitation (mm), Evapotranspiration (ETo), Crop evapotranspiration (ETc), and Irrigation (Hours), during the wheat-growing winter season in the drought year 2021 to understand the reasons for the varian...
In the past two decades, severe drought has been a recurrent problem in Iraq due in part to clima... more In the past two decades, severe drought has been a recurrent problem in Iraq due in part to climate change. Additionally, the catastrophic drop in the discharge of the Tigris and Euphrates rivers and their tributaries has aggravated the drought situation in Iraq, which was formerly one of the most water-rich nations in the Middle East. The Kurdistan Region of Iraq (KRI) also has catastrophic drought conditions. This study analyzed a Landsat time-series dataset from 1998 to 2021 to determine the drought severity status in the KRI. The Modified Soil-Adjusted Vegetation Index (MSAVI2) and Normalized Difference Water Index (NDWI) were used as spectral-based drought indices to evaluate the severity of the drought and study the changes in vegetative cover, water bodies, and precipitation. The Standardized Precipitation Index (SPI) and the Spatial Coefficient of Variation (CV) were used as meteorologically based drought indices. According to this study, the study area had precipitation def...
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Drought is a common event in Iraq’s climate, and the country has severely suffered from drought e... more Drought is a common event in Iraq’s climate, and the country has severely suffered from drought episodes in the last two decades. The Kurdistan Region of Iraq (KRI) is geographically situated in the semi-arid zone in Iraq, whose water resources have been limited in the last decades and mostly shared with other neighboring countries. To analyze drought impacts on the vegetation cover and the land surface temperature in the KRI for a span of 20 years from 1998 to 2017, remote sensing (RS) and Geographical Information Systems (GIS) have been adopted in this study. For this study, 120 Landsat satellite images were downloaded and utilized, whereas six images covering the entire study area were used for each year of the study period. The Normalized Difference Vegetation Index (NDVI) and Land Surfaces Temperature Index (LST) were applied to produce multi-temporal classified drought maps. Changes in the area and values of the classified NDVI and LST were calculated and mapped. Mann–Kendall ...
IOP Conference Series: Earth and Environmental Science, 2021
Drought is a natural hazard that significantly impacts economic, agricultural, environmental, and... more Drought is a natural hazard that significantly impacts economic, agricultural, environmental, and social aspects and is characteristic of Iraq’s climate, particularly the Iraqi Kurdistan Region (IKR). For studying the spatiotemporal characteristics of drought severity in the IKR, a time-series of 120 Landsat images (TM, 7 ETM+, and OLI sensors) over twenty years (1998-2017) was assembled. Twenty separate mosaics of six Landsat scenes were used to derive the Vegetation Condition Index (VCI). The VCI index was employed to capture the drought severity in the study area. Results revealed that 1999, 2000, and 2008 were the most severe drought years. The results also indicated that severe droughts increased by 29.1%, 25.0%, and 26.9 through 1999, 2000, and 2008, respectively. Furthermore, a drop in precipitation averages occurred in the two years and significantly reduced the VCI values. Statistical analysis exhibited significant correlations between the VCI and each precipitation, and cr...
Drought is an extreme climate phenomenon that comprises climatic dubiety induced by the environme... more Drought is an extreme climate phenomenon that comprises climatic dubiety induced by the environment. Iraq experienced severely drought events in last decades, particularly Erbil Province in the Kurdistan Region. Over the last two decades, Erbil Province suffered from severe agricultural drought, causing a significant reduction in crop yield. The application of satellite-based indices for the assessment of drought severity assessment in semi-arid countries is well known. This study was sought to incorporate geoinformation technology into the evaluation of agricultural drought severity and its relationships with crop yield in Erbil Province throughout the years 1998-2017. Forty images of the Landsat satellites time-series 5 TM, 7 ETM+, and 8 OLI utilized for this study. Twenty mosaics of two scenes prepared to extract the MSAVI2 index. The results showed that the drought caused a reduction of crop yield, particularly in the years 2000, 2008, and 2012. Besides, a significant decline in the MSAVI2-based vegetation cover area by 22.3, 15.8, and 15.7% in the aforementioned years, respectively. The results also revealed significant relationships among the MSAVI2 values, vegetation area, rainfall, and crop yield. Whereas, it was (0.472*) between the MSAVI2 and rainfall, and (0.635**) between the MSAVI2 and crop yield. Furthermore, Erbil Province, suffered severe to exceptional agricultural drought episodes in its southern and western partsin the years 2000, 2008, and 2012. It can be concluded, that the MSAVI2 index is an efficient tool for evaluating the agriculture drought in Erbil Province, and its significant positive relationship with the crop yield is higher than the relationship with the rainfall.
Drought is a natural hazard that has a significant impact on the various aspects (i.e., economic,... more Drought is a natural hazard that has a significant impact on the various aspects (i.e., economic, agricultural, environmental, and social). This study was carried out to evaluate drought severity and frequency during the growing season (April month) in Duhok Governorate (DUG), the Iraqi Kurdistan Region (IKR), for the period from 1998 through 2012 based on Landsat-based spectral indices. In this study, 15 mosaics assembled for 15 years consist of two scenes of Landsat time series, in a total of 30 TM and ETM+ images (WRS2: 170/34 & 170/35) acquired in 1998 to 2012. Annual precipitation data were collected from 18 meteorological stations distributed in the (DUG) for the study period. Drought status was investigated using the Normalized Difference Vegetation Index (NDVI), Modified Soil Adjusted Vegetation Index (MSAVI2), and Normalized Difference Water Index (NDWI). The study results showed an increase in drought severity and frequency in the (DUG) during the fifty years, particularly...
Journal of Geoinformatics & Environmental Research
Spectral vegetation indices and their relations to some ecological and terrain variables in the I... more Spectral vegetation indices and their relations to some ecological and terrain variables in the Iraqi Kurdistan Region (IKR) is the main objective of this study. A mosaic of two Landsat-7 ETM+ images was utilized to produce five spectral vegetation indices, and Terra ASTER Digital Elevation Model (DEM) dataset were employed. The Normalized Difference Vegetation Index (NDVI), Soil Adjusted Vegetation Index (SAVI), Optimized Soil Adjusted Vegetation Index (OSAVI), Tasseled Cap Greenness, Land Surface Temperature (LST) were utilized for this study. The results of the current study revealed that MSAVI2 is more reliable and accurate in depicting the vegetation presence in the IKR, which is occupied 34.7% of the total study area in 2014. In terms of terrain variables, all vegetation indices responded to variation of aspect ratio variation. It was found that the densest vegetation exists between 180 to 350°. Mainly, in the South (157.5°-202.5°), Southwest (202.5°-247.5°), West (247.5°-292....
Journal of Advanced Research in Dynamical and Control Systems
Iraq, including Erbil Province in the Kurdistan region, has severely suffered drought events in t... more Iraq, including Erbil Province in the Kurdistan region, has severely suffered drought events in the past, particularly during the last two decades. This study incorporated Geoinformation technology into assessing and monitoring drought's severity and impacts that affected Erbil province in a span from 1998 to 2017. Twenty mosaics of two Landsat scenes for 20 years have accomplished for this study. Two spectral drought indices, the Normalized Difference Vegetation Index (NDVI) and the Temperature Condition Index (TCI), were extracted using 20 Landsat images mosaics to assess the drought's severity and impacts. Statistical correlation analyses computed between the NDVI, TCI, and the study variables, such as climatic factors, field crop area, and field crop yield. The study findings clarified that Erbil province experienced severe to extreme severe agricultural droughts, which caused significant reductions in crop yields, particularly in 2000, 2008, and 2012. The results also revealed significant declines in the vegetative cover in the years 2000, 2008 and 2012, by 43.8%, 16.3%, and 10.9%, respectively. Furthermore, a drop in precipitation averages has occurred in those three drought years, as well as a significant reduction in the TCI values. The study results clarified that the southern and western parts of Erbil Province were the most parts exposed to the severe to exceptional agricultural drought episodes throughout the twenty years of this study.
Drought was a severe recurring phenomenon in Iraq over the past two decades due to climate change... more Drought was a severe recurring phenomenon in Iraq over the past two decades due to climate change despite the fact that Iraq has been one of the most water-rich countries in the Middle East in the past. The Iraqi Kurdistan Region (IKR) is located in the north of Iraq, which has also suffered from extreme drought. In this study, the drought severity status in Sulaimaniyah Province, one of four provinces of the IKR, was investigated for the years from 1998 to 2017. Thus, Landsat time series dataset, including 40 images, were downloaded and used in this study. The Normalized Difference Vegetation Index (NDVI) and the Normalized Difference Water Index (NDWI) were utilized as spectral-based drought indices and the Standardized Precipitation Index (SPI) was employed as a meteorological-based drought index, to assess the drought severity and analyse the changes of vegetative cover and water bodies. The study area experienced precipitation deficiency and severe drought in 1999, 2000, 2008, 2009, and 2012. Study findings also revealed a drop in the vegetative cover by 33.3% in the year 2000. Furthermore, the most significant shrinkage in water bodies was observed in the Lake Darbandikhan (LDK), which lost 40.5% of its total surface area in 2009. The statistical analyses revealed that precipitation was significantly positively correlated with the SPI and the surface area of the LDK (correlation coefficients of 0.92 and 0.72, respectively). The relationship between SPI and NDVI-based vegetation cover was positive but not significant. Low precipitation did not always correspond to vegetative drought; the delay of the effect of precipitation on NDVI was one year.
Drought is a complex phenomenon that has severe impacts on the environment. Vegetation and its co... more Drought is a complex phenomenon that has severe impacts on the environment. Vegetation and its conditions are very sensitive to drought effects. This study aimed to monitor and assess the drought severity and its relationships to some ecological variables in ten districts of Erbil Governorate (Kurdistan Region), Iraq, throughout 20 years (1998-2017). The results revealed that droughts frequently hit Erbil throughout the study period. The Landsat time-series-based on Vegetation Condition Index (VCI) significantly correlated with precipitation, Digital Elevation Model (DEM), and latitude. Extreme VCI-based drought area percentages were
Drought is a complex phenomenon that has severe impacts on the environment. Vegetation and i... more Drought is a complex phenomenon that has severe impacts on the environment. Vegetation and its conditions are very sensitive to drought effects. This study aimed to monitor and assess the drought severity and its relationships to some ecological variables in ten districts of Erbil Governorate (Kurdistan Region), Iraq, throughout 20 years (1998-2017). The results revealed that droughts frequently hit Erbil throughout the study period. The Landsat time-series- based on Vegetation Condition Index (VCI) significantly correlated with precipitation, Digital Elevation Model (DEM), and latitude. Extreme VCI-based drought area percentages were recorded in 1999, 2000, 2008, and 2011 by 43.4%, 67.9%, 43.3%, and 40.0%, respectively. The highest crop yield reduction in the study area occurred mainly in 2000, 2008, and 2012 due to low precipitation rates. These results reveal the capability of the VCI for drought characteristics and highlighting relationships with some ecological variables, ...
IOP Conference Series: Earth and Environmental Science, 2021
Drought is a natural hazard that significantly impacts economic, agricultural, environmental, and... more Drought is a natural hazard that significantly impacts economic, agricultural, environmental, and social aspects and is characteristic of Iraq's climate, particularly the Iraqi Kurdistan Region (IKR). For studying the spatiotemporal characteristics of drought severity in the IKR, a time-series of 120 Landsat images (TM, ETM+, and OLI sensors) over twenty years (1998-2017) was assembled. Twenty separate mosaics of six Landsat scenes were used to derive the Vegetation Condition Index (VCI). The VCI index was employed to capture the drought severity in the study area. Results revealed that 1999, 2000, and 2008 were the most severe drought years. The results also indicated that severe droughts increased by 29.1%, 25.0%, and 26.9 through 1999, 2000, and 2008, respectively. Furthermore, a drop in precipitation averages occurred in the two years and significantly reduced the VCI values. Statistical analysis exhibited significant correlations between the VCI and each precipitation, and crop yield was 0.81 and 0.478, respectively. It can be concluded that the IKR experienced severe to extremely severe agricultural droughts, which caused significant reductions in crop yields, particularly in 2000 and 2008.
Drought was a severe recurring phenomenon in Iraq over the past two decades due to climate
change... more Drought was a severe recurring phenomenon in Iraq over the past two decades due to climate change despite the fact that Iraq has been one of the most water-rich countries in the Middle East in the past. The Iraqi Kurdistan Region (IKR) is located in the north of Iraq, which has also suffered from extreme drought. In this study, the drought severity status in Sulaimaniyah Province, one of four provinces of the IKR, was investigated for the years from 1998 to 2017. Thus, Landsat time series dataset, including 40 images, were downloaded and used in this study. The Normalized Difference Vegetation Index (NDVI) and the Normalized Difference Water Index (NDWI) were utilized as spectral-based drought indices and the Standardized Precipitation Index (SPI) was employed as a meteorological-based drought index, to assess the drought severity and analyse the changes of vegetative cover and water bodies. The study area experienced precipitation deficiency and severe drought in 1999, 2000, 2008, 2009, and 2012. Study findings also revealed a drop in the vegetative cover by 33.3% in the year 2000. Furthermore, the most significant shrinkage in water bodies was observed in the Lake Darbandikhan (LDK), which lost 40.5% of its total surface area in 2009. The statistical analyses revealed that precipitation was significantly positively correlated with the SPI and the surface area of the LDK (correlation coefficients of 0.92 and 0.72, respectively). The relationship between SPI and NDVI-based vegetation cover was positive but not significant. Low precipitation did not always correspond to vegetative drought; the delay of the effect of precipitation on NDVI was one year.
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Papers by Heman Gaznayee
change despite the fact that Iraq has been one of the most water-rich countries in the Middle East in the
past. The Iraqi Kurdistan Region (IKR) is located in the north of Iraq, which has also suffered from
extreme drought. In this study, the drought severity status in Sulaimaniyah Province, one of four provinces
of the IKR, was investigated for the years from 1998 to 2017. Thus, Landsat time series dataset, including
40 images, were downloaded and used in this study. The Normalized Difference Vegetation Index (NDVI)
and the Normalized Difference Water Index (NDWI) were utilized as spectral-based drought indices and
the Standardized Precipitation Index (SPI) was employed as a meteorological-based drought index, to
assess the drought severity and analyse the changes of vegetative cover and water bodies. The study area
experienced precipitation deficiency and severe drought in 1999, 2000, 2008, 2009, and 2012. Study
findings also revealed a drop in the vegetative cover by 33.3% in the year 2000. Furthermore, the most
significant shrinkage in water bodies was observed in the Lake Darbandikhan (LDK), which lost 40.5% of
its total surface area in 2009. The statistical analyses revealed that precipitation was significantly positively
correlated with the SPI and the surface area of the LDK (correlation coefficients of 0.92 and 0.72,
respectively). The relationship between SPI and NDVI-based vegetation cover was positive but not
significant. Low precipitation did not always correspond to vegetative drought; the delay of the effect of
precipitation on NDVI was one year.
change despite the fact that Iraq has been one of the most water-rich countries in the Middle East in the
past. The Iraqi Kurdistan Region (IKR) is located in the north of Iraq, which has also suffered from
extreme drought. In this study, the drought severity status in Sulaimaniyah Province, one of four provinces
of the IKR, was investigated for the years from 1998 to 2017. Thus, Landsat time series dataset, including
40 images, were downloaded and used in this study. The Normalized Difference Vegetation Index (NDVI)
and the Normalized Difference Water Index (NDWI) were utilized as spectral-based drought indices and
the Standardized Precipitation Index (SPI) was employed as a meteorological-based drought index, to
assess the drought severity and analyse the changes of vegetative cover and water bodies. The study area
experienced precipitation deficiency and severe drought in 1999, 2000, 2008, 2009, and 2012. Study
findings also revealed a drop in the vegetative cover by 33.3% in the year 2000. Furthermore, the most
significant shrinkage in water bodies was observed in the Lake Darbandikhan (LDK), which lost 40.5% of
its total surface area in 2009. The statistical analyses revealed that precipitation was significantly positively
correlated with the SPI and the surface area of the LDK (correlation coefficients of 0.92 and 0.72,
respectively). The relationship between SPI and NDVI-based vegetation cover was positive but not
significant. Low precipitation did not always correspond to vegetative drought; the delay of the effect of
precipitation on NDVI was one year.