On global and latitudinal scales, the observed variation in flood frequencies can be statistically explained by variations of four decadal and multidecadal climate oscillations: the El Niño–Southern Oscillation (ENSO), the Pacific Decadal Oscillation (PDO), the North Atlantic Oscillation (NAO), and the Atlantic Multidecadal Oscillation (AMO) 10. Extreme flood events show a similar non-monotonous temporal evolution with strongest long-term trends in Europe and the United States of America 11. Globally, 1985–2009 flood frequency has first increased, peaked around 2003, and decreased afterwards 10. Observed annual discharge maxima show regionally varying trends with significant increases in most stations of Asia, Europe, and Latin America and with mostly decreasing trends in Africa, Australia, and North America 9. In addition, there are more record-breaking rainfall events observed than would be expected in a stationary climate (12% increase in 1981–2010 7) and the observed intensification of extreme daily precipitation events since the 1980s has been attributed to anthropogenic global warming 8. These theoretical considerations were recently confirmed by observations showing a global median increase in annual maximum daily precipitation of 5.9–7.7% per degree of global warming 6. Therefore, extreme daily precipitation is expected to increase at a substantially higher rate of ~6–7% per degree of global mean warming 5. However, the intensity of extreme precipitation events is most relevant for fluvial flooding 3 and increases with the moisture of air that can be precipitated out according to the Clausius–Clapeyron relationship 4. Theoretical considerations on the global surface energy budget suggest that global mean precipitation increases with global mean temperature (GMT) at a rate of 1–2% per thousand of global mean warming 2. Since 1980, fluvial floods have caused more than 200,000 fatalities and more than $790 bn in direct economic damages globally 1, placing them among the most socially and economically devastating natural disasters. In most regions, we find monotonous climate-induced damage trends but more years of observations would be needed to distinguish between the impacts of anthropogenic climate forcing and multidecadal oscillations. However, when disaggregating the world regions into subregions based on river-basins with homogenous historical discharge trends, climate contributions to damages become statistically significant globally, in Asia and Latin America. We show that, on the level of nine world regions, trends in damages are dominated by increasing exposure and modulated by changes in vulnerability, while climate-induced trends are comparably small and mostly statistically insignificant, with the exception of South & Sub-Saharan Africa and Eastern Asia. We develop an empirical model to reconstruct observed damages and quantify the contributions of climate and socio-economic drivers to observed trends. Here, we investigate whether its signals are already detectable in reported river flood damages. Nevertheless, the United States is the biggest emitter in history in terms of cumulative emissions having produced more than 500 GtCO₂ from fossil fuels and land use since 1850.Climate change affects precipitation patterns. The increased burning of coal in China in recent decades has seen it become the world’s largest emitter, having overtaken the United States in the early 2000s. China is by far the largest producer of coal-fired electricity and is therefore responsible for a huge share of these emissions. There are many sources of GHG emissions but the single largest contributor is coal-fired electricity, which emits roughly eight GtCO₂ a year. This had led to policies such as the Global Methane Pledge being announced in a bid to cut emissions of this potent gas by 30 percent by 2030, relative to 2020 levels. The reduction in methane emissions until the end of the decade is one of the main focuses of recent climate pledges. These two GHGs have a greater global warming potential than CO₂, and the growth in their emissions is of great concern to climate scientists. While CO₂ is the most talked about GHG, annual emissions of methane and often-overlooked nitrous oxide have also reached record highs. Nevertheless, this increase was lower than previously expected due to the growth in deployment of renewable energy and other low-carbon technologies like heat pumps. This growth was primarily driven by increased coal combustion around the world as countries switched back to this polluting fuel during the energy crisis triggered by the Russia-Ukraine war. Global emissions reach record high Global carbon dioxide emissions from fossil fuels and cement are estimated to have risen by 0.9 percent in 2022 to a record high of 37.5 GtCO₂.
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