TY - JOUR
AU1 - Burke, Eleanor J.
AU2 - Brown, Simon J.
AB - The uncertainty in the projection of future drought occurrence was explored for four different drought indices using two model ensembles. The first ensemble expresses uncertainty in the parameter space of the third Hadley Centre climate model, and the second is a multimodel ensemble that additionally expresses structural uncertainty in the climate modeling process. The standardized precipitation index (SPI), the precipitation and potential evaporation anomaly (PPEA), the Palmer drought severity index (PDSI), and the soil moisture anomaly (SMA) were derived for both a single CO 2 (1××CO 2 ) and a double CO 2 (2××CO 2 ) climate. The change in moderate drought, defined by the 20th percentile of the relevant 1××CO 2 distribution, was calculated. SPI, based solely on precipitation, shows little change in the proportion of the land surface in drought. All the other indices, which include a measure of the atmospheric demand for moisture, show a significant increase with an additional 5%%––45%% of the land surface in drought. There are large uncertainties in regional changes in drought. Regions where the precipitation decreases show a reproducible increase in drought across ensemble members and indices. In other regions the sign and magnitude of the change in drought is dependent on index definition and ensemble member, suggesting that the selection of appropriate drought indices is important for impact studies.
TI - Evaluating Uncertainties in the Projection of Future Drought
JF - Journal of Hydrometeorology
DO - 10.1175/2007JHM929.1
DA - 2007-05-07
UR - https://www.deepdyve.com/lp/american-meteorological-society/evaluating-uncertainties-in-the-projection-of-future-drought-OwKzIIO4d7
SP - 292
EP - 299
VL - 9
IS - 2
DP - DeepDyve
ER -