Many certificateless signature schemes using bilinear pairings have been proposed. But the relative computation cost of the pairing is approximately twenty times higher than that of the scalar multiplication over elliptic curve group. In order to improve the performance we propose a certificateless signature scheme without bilinear pairings. With the running time being saved greatly, our scheme is more practical than the previous related schemes for practical application.

Under global warming, a novel category of extreme events has become increasingly apparent, where flood and hot extremes occur in rapid succession, causing significant damages to infrastructure and ecosystems. However, these bivariate compound flood‐hot extreme (CFH) hazards have not been comprehensively examined at the global scale, and their evolution under climate warming remains unstudied. Here, we present the first global picture of projected changes in CFH hazards by using a cascade modeling chain of CMIP6 models, satellite and reanalysis data sets, bias correction, and hydrological models. We find an increasing percentage of floods will be accompanied by hot extremes under climate change; the joint return periods of CFHs are projected to decrease globally, particularly in the tropics. These decreasing joint return periods are largely driven by changes in hot extremes and indicate a likely increase of CFH hazards, and ultimately highlight the urgent need to conduct adaptation planning for future risks.

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 This work summarizes the 40 years of research in the generation of streamflow forecasts based on an exhaustive review of studies.  Ensemble prediction systems are categorized into three classes: statistics-based, climatology-based and numerical weather prediction-based hydrological ensemble prediction systems.  For each ensemble forecasting system, thorough technical information is provided.  Findings from the success of the model-based ensemble forecasting approaches are analysed, as are prospective future developments.