Geology Reference
In-Depth Information
15
Modelling Impacts of Climatic
Change: Case Studies using
the New Generation
of Erosion Models
J.P. NUNES
1
AND M.A. NEARING
2
1
Centre for Environmental and Marine Studies (CESAM), Department of Environment
and Planning, University of Aveiro, Aveiro, Portugal
2
USDA-ARS, Southwest Watershed Research Center, Tucson, AZ, USA
15.1 Introduction
between climate change impacts. Erosion mod-
els can be useful assessment tools to support cli-
mate change studies, since they codify the
existing knowledge on soil erosion processes and
their response to climate forcing, allowing the
quantification of the impacts of changed climate
patterns in a feasible and, hopefully, robust way.
The purpose of this chapter is to explore these
challenges. It begins by discussing potential
impacts of climate change on soil erosion drivers
and processes, and potential interactions between
them. It then proceeds with a systematization of
soil erosion modelling applied to climate change
studies, discussing issues such as climate change
scenario and model selection, or calibration and
validation issues. This is followed by a number
of case studies from around the globe which
exemplify climate change impact assessment
supported by a modelling framework. The chap-
ter concludes with a discussion of research
results in this area, current limitations and poten-
tial avenues of future research.
There is a growing consensus in Earth systems
sciences that global temperatures are increasing
and will continue to do so during the next century,
leading to changes in global climate patterns (IPCC,
2007). Although different regions of the globe could
respond differently to global warming, most are
expected to suffer significant changes to the amount
and variability of rainfall and temperature (Giorgi,
2006), associated with an increase in the frequency
of extreme episodes such as heat waves and high-
intensity storms (Tebaldi
et al
., 2006).
These changes have the potential to alter sig-
nificantly the driving forces and parameters
behind soil erosion; examples include changes to
rainfall intensity, vegetation cover and surface
runoff generation (Kundzewicz
et al
., 2007).
There is therefore a need to quantify the impacts
of climate change on soil erosion and on the
most important erosion drivers, to estimate on-
and off-site consequences, and support the devel-
opment of adequate adaptation measures. This
can be a challenging problem due to the non-
linear relationships between soil erosion drivers
and processes and the complex interactions
15.2
Potential Impacts of Climatic Change
on Erosion Processes
Climate change is expected to impact upon a
number of soil erosion drivers and processes,
which should be taken into account when
