Impact of downscaled rainfall biases on projected runoff changes
Realistic projections of changes to daily rainfall frequency and magnitude, at catchment scales, are required to assess the potential impacts of climate change on regional water supply. We show that quantile–quantile mapping (QQM) bias-corrected daily rainfall from dynamically downscaled WRF simulat...
Saved in:
Published in | Hydrology and earth system sciences Vol. 24; no. 6; pp. 2981 - 2997 |
---|---|
Main Authors | , , , , , |
Format | Journal Article |
Language | English |
Published |
Katlenburg-Lindau
Copernicus GmbH
08.06.2020
Copernicus Publications |
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | Realistic projections of changes to daily rainfall
frequency and magnitude, at catchment scales, are required to assess the
potential impacts of climate change on regional water supply. We show that
quantile–quantile mapping (QQM) bias-corrected daily rainfall from
dynamically downscaled WRF simulations of current climate produce biased
hydrological simulations, in a case study for the state of Victoria,
Australia (237 629 km2). While the QQM bias correction can remove bias
in daily rainfall distributions at each 10 km × 10 km grid point across
Victoria, the GR4J rainfall–runoff model underestimates runoff when driven
with QQM bias-corrected daily rainfall. We compare simulated runoff
differences using bias-corrected and empirically scaled rainfall for several
key water supply catchments across Victoria and discuss the implications for
confidence in the magnitude of projected changes for mid-century. Our
results highlight the imperative for methods that can correct for temporal
and spatial biases in dynamically downscaled daily rainfall if they are to
be suitable for hydrological projection. |
---|---|
ISSN: | 1607-7938 1027-5606 1607-7938 |
DOI: | 10.5194/hess-24-2981-2020 |