TY - JOUR
T1 - Application of relative drought indices in assessing climate-change impacts on drought conditions in Czechia
AU - Dubrovsky, M.
AU - Svoboda, M. D.
AU - Trnka, M.
AU - Hayes, M. J.
AU - Wilhite, D. A.
AU - Zalud, Z.
AU - Hlavinka, P.
N1 - Funding Information:
The present study was sponsored by the Grant Agency of the Czech Republic (Project 205/05/2265 - “Calibration of Weather Generator for Sites without or with Incomplete Meteorological Observations”) and by the Ministry of Education, Youth and Sports of the Czech Republic (Research plan No. MSM6215648905 “Biological and Technological Aspects of Sustainability of Controlled Ecosystems and their Adaptability to Climate Change”). We also acknowledge support from the KONTAKT project ME 844, which has enabled intensive co-operation between the authors. We are grateful to Shifeng Zhang (Computer Science & Engineering Department, University of Nebraska, Lincoln), who made the necessary modifications to the source code of the PDSI. The Czech weather station data were provided by the Czech Hydrometeorological Institute.
PY - 2009
Y1 - 2009
N2 - The common versions (referred to as self-calibrated here) of the Standardized Precipitation Index (SPI) and the Palmer Drought Severity Index (PDSI) are calibrated and then applied to the same weather series. Therefore, the distribution of the index values is about the same for any weather series. We introduce here the relative SPI and PDSI, abbreviated as rSPI and rPDSI. These are calibrated using a reference weather series as a first step, which is then applied to the tested series. The reference series may result from either a different station to allow for the inter-station comparison or from a different period to allow for climate-change impact assessments. The PDSI and 1-24 month aggregations of the SPI are used here. In the first part, the relationships between the self-calibrated and relative indices are studied. The relative drought indices are then used to assess drought conditions for 45 Czech stations under present (1961-2000) and future (2060-2099) climates. In the present climate experiment, the drought indices are calibrated by using the reference station weather series. Of all drought indices, the PDSI exhibits the widest spectrum of drought conditions across Czechia, in part because it depends not only on precipitation (as does the SPI) but also on temperature. In our climate-change impact experiments, the future climate is represented by modifying the observed series according to scenarios based on five Global Climate Models (GCMs). Changes in the SPI-based drought risk closely follow the modeled changes in precipitation, which is predicted to decrease in summer and increase in both winter and spring. Changes in the PDSI indicate an increased drought risk at all stations under all climate-change scenarios, which relates to temperature increases predicted by all of the GCMs throughout the whole year. As drought depends on both precipitation and temperature, we conclude that the PDSI is more appropriate (when compared to the SPI) for use in assessing the potential impact of climate change on future droughts.
AB - The common versions (referred to as self-calibrated here) of the Standardized Precipitation Index (SPI) and the Palmer Drought Severity Index (PDSI) are calibrated and then applied to the same weather series. Therefore, the distribution of the index values is about the same for any weather series. We introduce here the relative SPI and PDSI, abbreviated as rSPI and rPDSI. These are calibrated using a reference weather series as a first step, which is then applied to the tested series. The reference series may result from either a different station to allow for the inter-station comparison or from a different period to allow for climate-change impact assessments. The PDSI and 1-24 month aggregations of the SPI are used here. In the first part, the relationships between the self-calibrated and relative indices are studied. The relative drought indices are then used to assess drought conditions for 45 Czech stations under present (1961-2000) and future (2060-2099) climates. In the present climate experiment, the drought indices are calibrated by using the reference station weather series. Of all drought indices, the PDSI exhibits the widest spectrum of drought conditions across Czechia, in part because it depends not only on precipitation (as does the SPI) but also on temperature. In our climate-change impact experiments, the future climate is represented by modifying the observed series according to scenarios based on five Global Climate Models (GCMs). Changes in the SPI-based drought risk closely follow the modeled changes in precipitation, which is predicted to decrease in summer and increase in both winter and spring. Changes in the PDSI indicate an increased drought risk at all stations under all climate-change scenarios, which relates to temperature increases predicted by all of the GCMs throughout the whole year. As drought depends on both precipitation and temperature, we conclude that the PDSI is more appropriate (when compared to the SPI) for use in assessing the potential impact of climate change on future droughts.
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U2 - 10.1007/s00704-008-0020-x
DO - 10.1007/s00704-008-0020-x
M3 - Article
AN - SCOPUS:64749088615
SN - 0177-798X
VL - 96
SP - 155
EP - 171
JO - Theoretical and Applied Climatology
JF - Theoretical and Applied Climatology
IS - 1-2
ER -