Frequency Of Severe Droughts Research Articles

Effect of climate change on gender roles among communities surrounding Lake Mburo National Park, Uganda

Background: Climate change has been increasingly recognized as a global crisis with effects on gender roles. Recently, communities surrounding Lake Mburo national park, Uganda have been experiencing frequent severe droughts. It was against this background that the study was designed to understand the effect of climate change on gender roles. Methods: This cross sectional study reviewed the effect of climate change on men and women’s gender roles using a pragmatic research paradigm based on a thematic review model using participatory methods and a structured questionnaire. Results: The study found that men and women’s gender roles were altered during extreme dryness. Men played their roles sequentially focusing on one single productive role, while women played their roles simultaneously, balancing the demands of each role with their limited available time. Effect of climate change affected productive roles more in Kiruhura district than Isingiro district. There was migration of both men and women in search of water and pasture for livestock in Kiruhura district which distorted gender roles of women. Consequently, women and girl children had a heavier load and were the most people affected by climate change effects in these districts. Conclusion: Gender roles of communities surrounding Lake Mburo National Park were affected and altered by the effects of climate change. Therefore, institutions offering climate services to local communities should consider gender in decision making, access to resources, information and knowledge during participation in climate change mitigation and adaptation.

Effect of climate change on gender roles among communities surrounding Lake Mburo National Park, Uganda

Background: Climate change has been increasingly recognized as a global crisis with effects on gender roles. Recently, communities surrounding Lake Mburo national park, Uganda have been experiencing frequent severe droughts. It was against this background that the study was designed to understand the effect of climate change on gender roles. Methods: This cross sectional study reviewed the effect of climate change on men and women's gender roles using a pragmatic research paradigm based on a thematic review model using participatory methods and a structured questionnaire. Results: The study found that men and women's gender roles were altered during extreme dryness. Men played their roles sequentially focusing on one single productive role, while women played their roles simultaneously, balancing the demands of each role with their limited available time. Effect of climate change affected productive roles more in Kiruhura district than Isingiro district. There was migration of both men and women in search of water and pasture for livestock in Kiruhura district which distorted gender roles of women. Consequently, women and girl children had a heavier load and were the most people affected by climate change effects in these districts. Conclusion: Gender roles of communities surrounding Lake Mburo National Park were affected and altered by the effects of climate change. Therefore, institutions offering climate services to local communities should consider gender in decision making, access to resources, information and knowledge during participation in climate change mitigation and adaptation.

Effect of climate variability on gender roles among communities surrounding Lake Mburo National Park, Uganda

Background: Climate change has been increasingly recognized as a global crisis with effects on gender roles. Recently, communities surrounding Lake Mburo national park, Uganda have been experiencing frequent severe droughts. It was against this background that this study was designed to understand effect of climate change on gender roles. Methods: This cross sectional study reviewed the effect of climate change on men and women’s gender roles using a pragmatic research paradigm based on a thematic review model using participatory methods and a structured questionnaire. Results: The study found that men and women’s gender roles were altered during extreme dryness. Men played their roles sequentially focusing on one single productive role, while women played their roles simultaneously, balancing the demands of each role with their limited available time. Effect of climate change variability affected productive roles more in Kiruhura district than Isingiro district. There was migration of both men and women in search for water and pasture livestock in Kiruhura district which distorted gender roles of women. Consequently, women and children had a heavier load and were the most people affected by climate change effects. Conclusion: Gender roles of communities surrounding Lake Mburo National Park, Uganda were affected and altered by the effects of climate change variability. Therefore, institutions offering climate services to local communities should consider gender in decision making, access to resources, information and knowledge.

Evaluating maize phenotype dynamics under drought stress using terrestrial lidar

BackgroundMaize (Zea mays L.) is the third most consumed grain in the world and improving maize yield is of great importance of the world food security, especially under global climate change and more frequent severe droughts. Due to the limitation of phenotyping methods, most current studies only focused on the responses of phenotypes on certain key growth stages. Although light detection and ranging (lidar) technology showed great potential in acquiring three-dimensional (3D) vegetation information, it has been rarely used in monitoring maize phenotype dynamics at an individual plant level.ResultsIn this study, we used a terrestrial laser scanner to collect lidar data at six growth stages for 20 maize varieties under drought stress. Three drought-related phenotypes, i.e., plant height, plant area index (PAI) and projected leaf area (PLA), were calculated from the lidar point clouds at the individual plant level. The results showed that terrestrial lidar data can be used to estimate plant height, PAI and PLA at an accuracy of 96%, 70% and 92%, respectively. All three phenotypes showed a pattern of first increasing and then decreasing during the growth period. The high drought tolerance group tended to keep lower plant height and PAI without losing PLA during the tasseling stage. Moreover, the high drought tolerance group inclined to have lower plant area density in the upper canopy than the low drought tolerance group.ConclusionThe results demonstrate the feasibility of using terrestrial lidar to monitor 3D maize phenotypes under drought stress in the field and may provide new insights on identifying the key phenotypes and growth stages influenced by drought stress.

The spatio-temporal characteristics of drought across Tibet, China: derived from meteorological and agricultural drought indexes

The droughts normally lead to devastating and long-lasting damage to agriculture, economy, and ecosystem, especially in Tibet Autonomous Region (hereafter Tibet) where ecosystem is fragile as a result of its special topographic, geomorphic, and climatic conditions. Due to limited observational data in this region, how often and where these droughts occur is not well understood. In this study, droughts intensity and frequency, as well as dryness condition over Tibet were assessed by using the Standardized Precipitation Evapotranspiration Index (SPEI) with meteorological data from 38 stations during period of 1971–2014. Temperature Vegetation Dryness Index (TVDI) was used to compared with SPEI based on observed drought area of Tibet. Moreover, the dryness condition was explained by the contribution of meteorological factors according to the method of contribution rate. Results indicated that dryness conditions were aggravating during the period 1971–2014 across Tibet. Besides, drought intensity and frequency presented considerable decadal variation over the past 44 years with more frequent moderate and severe drought occurring in period of 1981–1990 and 2001–2014 compared with other periods. This highlighted that Tibet has gone through serious drying in the 1970s and since 2000. Factor analysis indicated that precipitation played the most important role in the variation of SPEI-12M. Both drought indexes could effectively detect drought events over Tibet from 2001 to 2014. Investigating and evaluating drought characteristic, causes and drought indexes effectiveness provide essential information for balanced water resource allocation and utilization and drought prevention.

Rainfall trends and variation in the Maasai Mara ecosystem and their implications for animal population and biodiversity dynamics.

Rainfall exerts a controlling influence on the availability and quality of vegetation and surface water for herbivores in African terrestrial ecosystems. We analyse temporal trends and variation in rainfall in the Maasai Mara ecosystem of East Africa and infer their implications for animal population and biodiversity dynamics. The data originated from 15 rain gauges in the Mara region (1965–2015) and one station in Narok Town (1913–2015), in Kenya’s Narok County. This is the first comprehensive and most detailed analysis of changes in rainfall in the region of its kind. Our results do not support the current predictions of the International Panel of Climate Change (IPCC) of very likely increases of rainfall over parts of Eastern Africa. The dry season rainfall component increased during 1935–2015 but annual rainfall decreased during 1962–2015 in Narok Town. Monthly rainfall was more stable and higher in the Mara than in Narok Town, likely because the Mara lies closer to the high-precipitation areas along the shores of Lake Victoria. Predominantly deterministic and persistent inter-annual cycles and extremely stable seasonal rainfall oscillations characterize rainfall in the Mara and Narok regions. The frequency of severe droughts increased and floods intensified in the Mara but droughts became less frequent and less severe in Narok Town. The timings of extreme droughts and floods coincided with significant periodicity in rainfall oscillations, implicating strong influences of global atmospheric and oceanic circulation patterns on regional rainfall variability. These changing rainfall patterns have implications for animal population dynamics. The increase in dry season rainfall during 1935–2015 possibly counterbalanced the impacts of resource scarcity generated by the declining annual rainfall during 1965–2015 in Narok Town. However, the increasing rainfall extremes in the Mara can be expected to create conditions conducive to outbreaks of infectious animal diseases and reduced vegetation quality for herbivores, particularly when droughts and floods persist over multiple years. The more extreme wet season rainfall may also alter herbivore space use, including migration patterns.

Extreme drought boosts CO2 and CH4 emissions from reservoir drawdown areas

ABSTRACTAlthough previous studies suggest that greenhouse gas (GHG) emissions from reservoir sediment exposed to the atmosphere during drought may be substantial, this process has not been rigorously quantified. Here we determined carbon dioxide (CO2) and methane (CH4) emissions from sediment cores exposed to a drying and rewetting cycle. We found a strong temporal variation in GHG emissions with peaks when the sediment was drained (C emissions from permanently wet sediment and drained sediments were, respectively, 251 and 1646 mg m−2 d−1 for CO2 and 0.8 and 547.4 mg m−2 d−1 for CH4) and then again during rewetting (C emissions from permanently wet sediment and rewetted sediments were, respectively, 456 and 1725mg m−2 d−1 for CO2 and 1.3 and 3.1 mg m−2 d−1 for CH4). To gain insight into the importance of these emissions at a regional scale, we used Landsat satellite imagery to upscale our results to all Brazilian reservoirs. We found that during the extreme drought of 2014–2015, an additional 1299 km2 of sediment was exposed, resulting in an estimated emission of 8.5 × 1011 g of CO2-eq during the first 15 d after the overlying water disappeared and in the first 33 d after rewetting, the same order of magnitude as the year-round GHG emissions of large (∼mean surface water area 454 km2) Brazilian reservoirs, excluding the emissions from the draw-down zone. Our estimate, however, has high uncertainty, with actual emissions likely higher. We therefore argue that the effects of drought on reservoir GHG emissions merits further study, especially because climate models indicate an increase in the frequency of severe droughts in the future. We recommend incorporation of emissions during drying and rewetting into GHG budgets of reservoirs to improve regional GHG emission estimates and to enable comparison between GHG emissions from hydroelectric and other electricity sources. We also emphasize that peak emissions at the onset of drought and the later rewetting should be quantified to obtain reliable emission estimates.

ВЕРОЯТНОСТНАЯ ОЦЕНКА ПОВТОРЯЕМОСТИ ЗАСУХ И ОПРЕДЕЛЕНИЕ РИСКОВ АГРАРНОГО ПРОИЗВОДСТВА

PURPOSE. The article presents various methods of drought evaluation, considers the trends of climate variability for the last 70 years that affect the frequency of droughts in the Irkutsk region. METHODS. The data on the yield of wheat as the main grain crop are used to evaluate the probability of droughts. Three groups including random samples, sequences with autocorrelation links and trends are distinguished based on the results of the statistical analysis of the long-term series of wheat bioproductivity. RESULTS. The proposed algorithms allowed to determine the statistical parameters of wheat yield series taking into account their specific features. Having obtained the probabilities of drought occurrence, we distinguished five groups of municipal districts. Based on the proposed methodology of extreme weather event probability estimation, the values of severe drought frequency in 2015 were calculated as well as the damages and possible insurance reimbursements. CONCLUSIONS. It is proposed to use the probabilistic models of drought frequency with the purpose to improve the planning of food production in different natural and climatic areas.

Fifty years of groundwater science in Korea: a review and perspective

We present a review of groundwater studies over the past 50 years (1968–2017) in Korea. With economic and agricultural growth, water demand has been expanding, and groundwater development is gradually increasing. Initially, groundwater studies were largely focused on using pumping and slug tests to understand aquifers in Korea. However, the interest has expanded to groundwater monitoring and data analyses, as many national and local networks for monitoring groundwater quantity and quality have been implemented. Frequent severe droughts in recent decades have led to research on the design and pilot tests for managed aquifer recharge, especially on the volcanic island of Jeju and agricultural areas. As groundwater development and its use has increased, groundwater contamination is becoming a public grievance. Thus, effective investigation of contaminated groundwater and its efficient remediation are big issues in the Research and Development (R & D) sector. The recent Gyeongju earthquake posed an additional challenge for Korean groundwater scientists to develop a method to predict earthquakes using groundwater monitoring. Furthermore, changes in precipitation patterns caused by the changing climate aggravate groundwater recharge conditions. The country has seen many academic and technical achievements in groundwater science, but many issues remain to be resolved in the near future.

Spatial-Temporal Variation of Drought in China from 1982 to 2010 Based on a modified Temperature Vegetation Drought Index (mTVDI)

Droughts cause huge losses of society and environment, therefore it is important to study the spatial-temporal pattern of drought. The traditional remote sensing drought indices (AVI, VCI and TCI) only consider the single factor representing the soil moisture (surface temperature or NDVI). The comprehensive remote sensing drought indices (VSWI and TVDI) can estimate the soil moisture more accurately, but they are not suitable for large scale region especially with great elevation variation. In this study, a modified Temperature Vegetation Drought Index (mTVDI) was constructed based on the correction of elevation and dry edge. Compared with the traditional drought indices, mTVDI had a better relationship with soil moisture in all selected months (R = −0.376, −0.406, −0.459, and −0.265, p < 0.05). mTVDI was used to analyze the spatial-temporal patterns of drought in China from 1982 to 2010. The results showed that droughts appeared more frequently in Northwest China and the southwest of Tibet while drought centers of North and Southwest China appeared in Huanghuaihai Plain and Yunnan-Guizhou Plateau respectively. The frequency of drought was increasing as a whole while the frequency of severe drought increased significantly by 4.86% and slight drought increased slowly during 1982 to 2010. The results are useful for the understanding of drought and policy making of climate change.

Assessment of meteorological drought characteristics over Central India

Employing the monthly precipitation data for the period of 113 years (1901–2013), the present study analyses the meteorological drought characteristics in 105 districts of Central India covering the states of Madhya Pradesh, Maharashtra, Chhattisgarh and the southern part of Uttar Pradesh. The various drought characteristics are frequency, severity (i.e., magnitude of deficit) and persistence (i.e., the occurrence of an event for two or more consecutive years). The region has semiarid to subhumid climate with average annual rainfall ranging between 600 and 1500 mm. The percentage departures of annual and seasonal rainfall from the corresponding mean have been applied for identification of onset and termination, and quantification of severity of drought events. The analysis indicated that the average drought frequency varies from once in 5 years to once in 9 years in major part of the Central India. Korba and Raigarh in Chhattisgarh and Bhandara in Maharashtra are the three districts where the rainfall records indicate that the average frequency of drought had been once in 10 years. The region had also faced severe drought events with the maximum rainfall deficiency of 75% occurred in Dewas district of Madhya Pradesh in 1904. The estimates show that average frequency of severe droughts in the region is to be more than 10 years accept Sheopur and Mandsaur districts experienced the severe drought once in 10 years. The extreme events in this region are almost none. There have been numerous persistent drought events for two, three, and four consecutive years. It is hoped that the information reported in this study can help for effective drought risk management in Central India.

Regional variation in Holocene climate quantified from pollen in the Great Plains of North America

ABSTRACTThe Great Plains experienced extreme fluctuations in precipitation and temperature throughout the Holocene, but these fluctuations have been difficult to quantify systematically across the region. Pollen has long been used as a proxy for reconstructing climate changes, but its power is limited if a region is devoid of modern pollen samples to facilitate comparison with known climate conditions. Here, we present a set of pollen‐climate transfer functions developed using weighted‐averaging partial least squares to reconstruct mean annual precipitation (MAP), mean temperature of the coldest month (MTcold) and mean temperature of the warmest month (MTwarm). At the foundation of these transfer functions is a new set of 141 modern pollen samples that specifically cover the climate space of the Great Plains. These functions quantify the relationship between pollen assemblages and modern climate in this region (r = 0.928, 0.838 and 0.897 for MAP, MTcold and MTwarm, respectively). We applied these functions to three previously established pollen records taken from lacustrine sites in the region – Fox Lake, MN; Moon Lake, ND; and Kettle Lake, ND – to reconstruct precipitation and temperature at these sites throughout the Holocene. Annual precipitation reconstructed with these transfer functions at Moon Lake and Kettle Lake does not capture a severe, prolonged period of drought during the mid‐Holocene as seen in many other proxy records from these sites and from the region. Reconciliation of these results involves both the autecology of Ambrosia and the inability of any pollen surface samples to capture seasonal and short‐term variability in precipitation. Thus, the transfer functions correctly reconstruct periodic wet summers and a disturbance factor favouring Ambrosia, but miss the effects of reduced winter precipitation and increased frequency of severe drought. The problem revealed here may be more general to biomes with higher frequency disturbance regimes and more weedy species.

Analysis of the spatial-temporal variation characteristics of vegetative drought and its relationship with meteorological factors in China from 1982 to 2010.

Drought is a complex natural phenomenon that can cause reduced water supplies and can consequently have substantial effects on agriculture and socioeconomic activities. The objective of this study was to gain a better understanding of the spatial-temporal variation characteristics of vegetative drought and its relationship with meteorological factors in China. The Vegetation Condition Index (VCI) dataset calculated from NOAA/AVHRR images from 1982 to 2010 was used to analyse the spatial-temporal variation characteristics of vegetative drought in China. This study also examined the trends in meteorological factors and their influences on drought using monitoring data collected from 686 national ground meteorological stations. The results showed that the VCI appeared to slowly rise in China from 1982 to 2010. From 1982 to 1999, the VCI rose slowly. Then, around 2000, the VCI exhibited a severe fluctuation before it entered into a relatively stable stage. Drought frequencies in China were higher, showing a spatial distribution feature of "higher in the north and lower in the south". Based on the different levels of drought, the frequencies of mild and moderate drought in four geographical areas were higher, and the frequency of severe drought was higher only in ecologically vulnerable areas, such as the Tarim Basin and the Qaidam Basin. Drought was mainly influenced by meteorological factors, which differed regionally. In the northern region, the main influential factor was sunshine duration, while the other factors showed minimal effects. In the southern region and Tibetan Plateau, the main influential factors were sunshine duration and temperature. In the northwestern region, the main influential factors were wind velocity and station atmospheric pressure.

Future impacts of global warming and reforestation on drought patterns over West Africa

This study investigates how a large-scale reforestation in Savanna (8–12°N, 20°W–20°E) could affect drought patterns over West Africa in the future (2031–2060) under the RCP4.5 scenario. Simulations from two regional climate models (RegCM4 and WRF) were analyzed for the study. The study first evaluated the performance of both RCMs in simulating the present-day climate and then applied the models to investigate the future impacts of global warming and reforestation on the drought patterns. The simulated and observed droughts were characterized with the Standardized Precipitation and Evapotranspiration Index (SPEI), and the drought patterns were classified using a Self-organizing Map (SOM) technique. The models capture essential features in the seasonal rainfall and temperature fields (including the Saharan Heat Low), but struggle to reproduce the onset and retreat of the West African Monsoon as observed. Both RCMs project a warmer climate (about 1–2 °C) over West Africa in the future. They do not reach a consensus on future change in rainfall, but they agree on a future increase in frequency of severe droughts (by about 2 to 9 events per decade) over the region. They show that reforestation over the Savanna could reduce the future warming by 0.1 to 0.8 °C and increase the precipitation by 0.8 to 1.2 mm per day. However, the impact of reforestation on the frequency of severe droughts is twofold. While reforestation decreases the droughts frequency (by about 1–2 events per decade) over the Savanna and Guinea coast, it increases droughts frequency (by 1 event per decade) over the Sahel, especially in July to September. The results of this study have application in using reforestation to mitigate impacts of climate change in West Africa.

Meteorological drought analysis in northern Iraq using SPI and GIS

Droughts are major natural disasters for many parts of the world. Iraq is one of the countries which are recently facing frequent severe drought events, especially the northern region which is considered as the breadbasket of the country. Successful management of water in droughts needs understanding its causes and development. The study aimed to discuss the effects of drought with its features; frequency of occurrence and spatial distribution, to recognize drought covered areas’ distribution and drought impact on the northern region of Iraq. The study utilizes the standardized precipitation index (SPI) at different time scales, i.e., 3, 6, 12, and 24-month, to analyze the meteorological drought. Monthly rainfall data for the period 1937–2010 were utilized from nine meteorological stations scattered in the study area to assess SPI values. Drought distribution within the study area with different time scales was mapped employing the geographic information system. Our results showed that the study area has suffered from frequent severe drought events, which were hitting in nearly every decade, and the most severe drought periods were during the years 1997–2001 and 2006–2010. The results exposed that most of the drought events fall in mild drought category according to the SPI classification. Besides, it has been shown that the eastern part of the study area has experienced many severe droughts considering accumulated deficits and drought period length. However, the severe drought events were much harmful on the western part of the study area due to its low annual rainfall rates.

Active microwave observations of diurnal and seasonal variations of canopy water content across the humid African tropical forests

AbstractA higher frequency of severe droughts under warmer temperatures is expected to lead to large impacts on global water and carbon fluxes and on vegetation cover—including possible widespread mortality. Monitoring the hydraulic state of vegetation as represented by the canopy water content will allow rapid assessment of vegetation water stress. Here we show the potential of active microwave backscatter observations at Ku band for monitoring the diurnal and seasonal variations of top‐of‐canopy water content. We focus on the humid tropical forests of Central Africa and examine spatiotemporal variations of radar backscatter from QuikSCAT (2001–2009) and RapidScat (2014–2016). Diurnal variations in RapidScat backscatter demonstrate the occurrence of widespread midday stomatal closure in this region. Increases in backscatter during the dry seasons in humid forests could be explained by both dry season leaf flushing (as supported by canopy structure) and vapor pressure deficit‐driven increases in evapotranspiration rates.

Potential socio-economic implications of future climate change and variability for Nigerien agriculture: A countrywide dynamic CGE-Microsimulation analysis

This study explores the potential economic and social effects induced by a possible future deterioration of weather conditions on Niger's agriculture. Our scenarios over a 25 year period rely on both long term climate change deterministic features and climate variability stochastic features which take into account a higher than normal frequency of severe droughts. Using a microsimulated Dynamic Recursive Computable General Equilibrium model, we show how a long run mean decrease in main crop yields could adversely affect growth, poverty and food security in the country and how more severe drought would worsen these negative effects. However, we also show that there would appear to be some room for manœuvre for coping strategies for Niger such as improving the rural road network, adopting modern crop varieties or, to a lesser extent, extending irrigation capacity.

Wildlife Population Dynamics in Human-Dominated Landscapes under Community-Based Conservation: The Example of Nakuru Wildlife Conservancy, Kenya.

Wildlife conservation is facing numerous and mounting challenges on private and communal lands in Africa, including in Kenya. We analyze the population dynamics of 44 common wildlife species in relation to rainfall variation in the Nakuru Wildlife Conservancy (NWC), located in the Nakuru-Naivasha region of Kenya, based on ground total counts carried out twice each year from March 1996 to May 2015. Rainfall in the region was quasi-periodic with cycle periods dependent on the rainfall component and varying from 2.8 years for the dry season to 10.9 years for the wet season. These oscillations are associated with frequent severe droughts and food scarcity for herbivores. The trends for the 44 wildlife species showed five general patterns during 1996–2015. 1) Steinbuck, bushbuck, hartebeest and greater kudu numbers declined persistently and significantly throughout 1996–2015 and thus merit the greatest conservation attention. 2) Klipspringer, mongoose, oribi, porcupine, cheetah, leopard, ostrich and Sykes monkey numbers also decreased noticeably but not significantly between 1996 and 2015. 3) Dik dik, eland, African hare, Jackal, duiker, hippo and Thomson’s gazelle numbers first increased and then declined between 1996 and 2015 but only significantly for duiker and hippo. 4) Aardvark, serval cat, colobus monkey, bat-eared fox, reedbuck, hyena and baboon numbers first declined and then increased but only the increases in reedbuck and baboon numbers were significant. 5) Grant’s gazelle, Grevy’s zebra, lion, spring hare, Burchell’s zebra, bushpig, white rhino, rock hyrax, topi, oryx, vervet monkey, guinea fowl, giraffe, and wildebeest numbers increased consistently between 1996 and 2015. The increase was significant only for rock hyrax, topi, vervet monkey, guinea fowl, giraffe and wildebeest. 6) Impala, buffalo, warthog, and waterbuck, numbers increased significantly and then seemed to level off between 1996 and 2015. The aggregate biomass of primates and carnivores increased overall whereas that of herbivores first increased from 1996 to 2006 and then levelled off thereafter. Aggregate herbivore biomass increased linearly with increasing cumulative wet season rainfall. The densities of the 30 most abundant species were either strongly positively or negatively correlated with cumulative past rainfall, most commonly with the early wet season component. The collaborative wildlife conservation and management initiatives undertaken on the mosaic of private, communal and public lands were thus associated with increase or no decrease in numbers of 32 and decrease in numbers of 12 of the 44 species. Despite the decline by some species, effective community-based conservation is central to the future of wildlife in the NWC and other rangelands of Kenya and beyond and is crucially dependent on the good will, effective engagement and collective action of local communities, working in partnerships with various organizations, which, in NWC, operated under the umbrella of the Nakuru Wildlife Forum.

What Do Climate Change Projections Say About Future Droughts in Alabama and Georgia?

Abstract. Frequent severe droughts in recent years in the humid southeast U.S. have called for pragmatic approaches to better prepare for the consequences of droughts. This article examines how climate change will influence future droughts in Alabama and Georgia. Historic and future droughts were quantified by means of the standardized precipitation index (SPI) and standardized precipitation evapotranspiration index (SPEI), and changes in the frequency, severity, and spatial extent of droughts were examined using severity-area-frequency (SAF) curves. Precipitation and temperature data, regionally downscaled using a regional spectral model (RSM) for the southeast U.S. for the high emission scenario (A2) from three general circulation models (GCM), i.e., Hadley Centre Coupled Model Version 3 (HadCM3), Geophysical Fluid Dynamics Laboratory (GFDL), and Community Climate System Model (CCSM), from the Third Coupled Model Inter-comparison Project (CMIP3) archive were used for this study. Data from 1969 to 1999 were used for historical simulation, and 2039 to 2069 were used for future projections. The results showed that droughts similar to those in the past would be observed frequently in the future as well. The SPI and SPEI from the GFDL and HadCM3 models indicated higher frequency, severity, and spatial extent of droughts in the future. The SPI from the CCSM model did not show drastic changes in drought characteristics in either of the two states. The results of this research can be used by policymakers as a guide to determine how drought characteristics are expected to change in the future, and to develop drought mitigation policies. Keywords: Climate change, Drought, Drought indices, Severity-area-frequency curves, Standardized precipitation index, Standardized precipitation evapotranspiration index.

Alteration of hydrologic indicators for Korean catchments under CMIP5 climate projections

The change of hydrological regimes may cause impacts on human and natural system. Therefore, investigation of hydrologic alteration induced by climate change is essential for preparing timely proper adaptation to the changes. This study employed 24 climate projections from the Coupled Model Intercomparison Project Phase 5 (CMIP5) under Representative Concentration Pathway (RCP) 4.5 scenario. The climate projections were downscaled at a station-spacing for seven Korean catchments by a statistical downscaling method that preserves a long-term trend in climate projections. Using an ensemble of future hydrologic projections simulated by three conceptual rainfall-runoff models (GR4J, IHACRES, and Sacramento models), we calculated Hydrologic Alteration Factors (HAFs) to investigate degrees of variations in Indicators of Hydrologic Alteration (IHAs) derived from the hydrologic projections. The results showed that the seven catchments had similar trend in terms of the HAFs for the 24 IHAs. Given that more frequent severe floods and droughts were projected over Korean catchments, sound water supply strategies are definitely required to adapt to the alteration of streamflow. A wide range of HAFs between rainfall-runoff models for each catchment was detected by large variations in the magnitude of HAFs with the hydrologic models and the difference could be the hydrologic prediction uncertainty. There were no-consistent tendency in the order of HAFs between the hydrologic models. In addition, we found that the alterations of hydrologic regimes by climate change are smaller as the size of catchment is larger. Copyright © 2016 John Wiley & Sons, Ltd.