Effects of Internal Climate Variability on Historical Ocean Wave Height Trend Assessment

This study assesses the effects of internal climate variability on wave height trend assessment using d4PDF-WaveHs, first single model initial-condition large ensemble (100-member) significant ( H s ) simulations for 1951–2010 period, which was produced sea level pressure taken from Japan’s d4PDF historical simulations. Here, focus is assessing trends in annual mean and maximum . The result compared with other that account sources uncertainty, modern reanalyses. It shown arising comparable to caused by factors, such as uncertainty. also likelihood mis-estimate when only one member therefore possible realization system. Using failed detect statistically notable positive some areas Southern Ocean. North Atlantic Ocean found have variability, where different ensemble-members can show opposite signs same area. minimum size necessary effectively reduce risk mis-assessing estimated be 10; but this largely depends specific statistic region interest, larger ensembles being required assess extremes. results reanalyses are not suitable analyzing due temporal inhomogeneities therein, agreement recent studies.