The aim of this paper is to investigate characteristics of meteorological and agricultural droughts and their trends in Iran, as well as several subregions with different climate conditions from 1980 to 2013. The Standardized Precipitation Index (SPI) and Standardized Soil Moisture Index (SSI) are used as the primary indicators of meteorological and agricultural droughts, respectively. This stu...

The development of paleoclimate streamflow reconstructions in the conterminous United States (CONUS) has provided water resource managers with improved insights into multi-decadal and centennial scale variability that cannot be reliably detected using shorter instrumental records. Paleoclimate streamflow reconstructions have largely focused on individual catchments limiting the ability to quant...

Recent advances in paleoclimatology have revealed dramatic long-term hydroclimatic variations that provide a context for limited historical records. A notable data set derived from a relatively dense network of paleoclimate proxy records in North America is the Living Blended Drought Atlas (LBDA): a gridded tree-ring-based reconstruction of summer Palmer Drought Severity Index. This index has b...

The world is currently experiencing average high temperatures and low precipitation, frequent droughts and scarcity of both ground and surface water. The damaging effects of global climate change are increasing and most damages are predicted to occur in developing countries due to their over-reliance on low-input rain-fed agricultural production and their low adaptive capacity. Due to the errat...

[1] During the Medieval Climate Anomaly, North America experienced severe droughts and widespread mobilization of dune fields that persisted for decades. We use an atmosphere general circulation model, forced by a tropical Pacific sea surface temperature reconstruction and changes in the land surface consistent with estimates of dune mobilization (conceptualized as partial devegetation), to inv...

Pollen and algae microfossils preserved in sediments from Pyramid Lake, Nevada, provide evidence for periods of persistent drought during the Holocene age. We analyzed one hundred nineteen 1-cm-thick samples for pollen and algae from a set of cores that span the past 7630 years. The early middle Holocene, 7600 to 6300 cal yr B.P., was found to be the driest period, although it included one shor...

The Haihe river basin (HRB) in the North China has been experiencing prolonged, severe droughts in recent years that are accompanied by precipitation deficits and vegetation wilting. This paper analyzed the water deficits related to spatiotemporal variability of three variables of the gravity recovery and climate experiment (GRACE) derived terrestrial water storage (TWS) data, precipitation, an...

introduction drought is a climatic hazard that occurs in the vast areas throughout the world. it causes physical suffering, economic losses, and environmental instability. drought is a slowly developing very which is phenomenon, and it is very difficult to determine when a dry spell becomes a drought or when a severe drought becomes an exceptional drought. it is usually starting with less drama...

General circulation models (GCMs) are routinely used to simulate future climatic conditions. However, rainfall outputs from GCMs are highly uncertain in preserving temporal correlations, frequencies, and intensity distributions, which limits their direct application for downscaling and hydrological modeling studies. To address these limitations, raw outputs of GCMs or regional climate models ar...

Climate projections in Sub-Saharan Africa (SSA) forecast an increase in the intensity and frequency of droughts with implications for maize production. While studies have examined how maize might be affected at the continental level, there have been few national or sub-national studies of vulnerability. We develop a vulnerability index that combines sensitivity, exposure and adaptive capacity a...