Abstract
While warming temperatures are known to increase atmospheric moisture
capacity and heavy precipitation frequency; as yet there is little
evidence for corresponding increases in floods. This study
comprehensively examines global changes in multidimensional flood
behaviors (magnitude, frequency, and duration), and aims to identify the
possible mechanisms behind the heavy precipitation and flood change
dichotomy. Our global assessment shows that floods become more frequent
but not larger. Regionally, consistent changes can be observed among
multidimensional flood behaviors, i.e., floods becoming larger in
magnitude, more frequent, and longer in duration in some regions (e.g.,
North Europe), while smaller, less frequent, and shorter in other
regions (e.g., South Australia). Attribution analysis indicates that
spatial patterns of global flood trends are primarily controlled by
shifts in atmospheric circulation patterns, terrestrial water storage
changes, and temperature increases. The dams are crucial for reducing
the floods, with the greatest impacts on flood magnitude, followed by
flood frequency and duration. Catchment characteristics (i.e.,
vegetation coverage, irrigation, and urbanization) regulate the response
of flood changes to changing environments.