Hydrography, circulation, and response to atmospheric forcing in the vicinity of the central Getz Ice Shelf, Amundsen Sea, Antarctica Ocean Science DOI 10.5194/os-18-1339-2022 7 December 2022 Ice shelves in the Amundsen Sea are thinning rapidly as ocean currents bring warm water into cavities beneath the floating ice. We use 2-year-long mooring records and 16-year-long model simulations to describe the hydrography and circulation near the ice front between Siple and Carney Islands. We find that temperatures here are lower than at neighbouring ice fronts and that the transport of heat toward the cavity is governed by wind stress over the Amundsen Sea continental shelf. Read more
Shallow marine carbonates as recorders of orbitally induced past climate changes – example from the Oxfordian of the Swiss Jura Mountains Climate of the Past DOI 10.5194/cp-18-2117-2022 5 December 2022 Some 155 million years ago, sediments were deposited in a shallow subtropical sea. Coral reefs formed in a warm and arid climate during high sea level, and clays were washed into the ocean at low sea level and when it rained. Climate and sea level changes were induced by cyclical insolation changes. Analysing the sedimentary record, it appears that sea level rise today (as a result of global warming) is more than 10 times faster than the fastest rise reconstructed from the geologic past. Read more
Contrasting drought legacy effects on gross primary productivity in a mixed versus pure beech forest Biogeosciences DOI 10.5194/bg-19-4315-2022 2 December 2022 Identifying drought legacy effects is challenging because they are superimposed on variability driven by climate conditions in the recovery period. We develop a residual-based approach to quantify legacies on gross primary productivity (GPP) from eddy covariance data. The GPP reduction due to legacy effects is comparable to the concurrent effects at two sites in Germany, which reveals the importance of legacy effects. Our novel methodology can be used to quantify drought legacies elsewhere. Read more
Recession or resilience? Long-range socioeconomic consequences of the 17th century volcanic eruptions in northern Fennoscandia Climate of the Past DOI 10.5194/cp-18-2077-2022 30 November 2022 Tree-ring data and written sources from northern Fennoscandia reveal that large 17th century eruptions had considerable climatic, agricultural, and socioeconomic impacts far away from the eruption locations. Yet, micro-regional investigation shows that the human consequences were commonly indirect, as various factors, like agro-ecosystems, resource availability, institutions, and personal networks, dictated how the volcanic cold pulses and related crop failures materialized on a societal level. Read more
HORAYZON v1.2: an efficient and flexible ray-tracing algorithm to compute horizon and sky view factor Geoscientific Model Development DOI 10.5194/gmd-15-6817-2022 28 November 2022 Terrain horizon and sky view factor are crucial quantities for many geoscientific applications; e.g. they are used to account for effects of terrain on surface radiation in climate and land surface models. Because typical terrain horizon algorithms are inefficient for high-resolution (< 30 m) elevation data, we developed a new algorithm based on a ray-tracing library. A comparison with two conventional methods revealed both its high performance and its accuracy for complex terrain. HORAYZON v1.2: an efficient and flexible ray-tracing algorithm to compute horizon and sky view factor">Read more
Reliability of flood marks and practical relevance for flood hazard assessment in southwestern Germany Natural Hazards and Earth System Sciences DOI 10.5194/nhess-22-2963-2022 25 November 2022 Encouraging a systematic use of flood marks for more comprehensive flood risk management, we collected a large number of marks along the Kinzig, southwestern Germany, and tested them for plausibility and temporal continuance. Despite uncertainty, the marks appeared to be an overall consistent and practical source that may also increase flood risk awareness. A wide agreement between the current flood hazard maps and the collected flood marks moreover indicated a robust local hazard assessment. Read more
South American Summer Monsoon variability over the last millennium in paleoclimate records and isotope-enabled climate models Climate of the Past DOI 10.5194/cp-18-2045-2022 23 November 2022 We evaluated the South American Summer Monsoon over the last millennium and dynamically interpreted the principal modes of variability. We find the spatial patterns of the monsoon are an intrinsic feature of the climate modulated by external forcings. Multi-centennial mean state departures during the Medieval Climate Anomaly and Little Ice Age show regionally coherent patterns of hydroclimatic change in both a multi-archive network of oxygen isotope records and isotope-enabled climate models. Read more
Ice core evidence for major volcanic eruptions at the onset of Dansgaard–Oeschger warming events Climate of the Past DOI 10.5194/cp-18-2021-2022 21 November 2022 Major volcanic eruptions are known to cause considerable short-term impacts on the global climate. Their influence on long-term climate variability and regime shifts is less well-understood. Here we show that very large, bipolar eruptions occurred more frequently than expected by chance just before abrupt climate change events in the last glacial period (Dansgaard–Oeschger events). Thus, such large eruptions may in some cases act as short-term triggers for abrupt regime shifts of the climate. Read more
Comprehensive space–time hydrometeorological simulations for estimating very rare floods at multiple sites in a large river basin Natural Hazards and Earth System Sciences DOI 10.5194/nhess-22-2891-2022 18 November 2022 Estimating the magnitude of rare to very rare floods is a challenging task due to a lack of sufficiently long observations. The challenge is even greater in large river basins, where precipitation patterns and amounts differ considerably between individual events and floods from different parts of the basin coincide. We show that a hydrometeorological model chain can provide plausible estimates in this setting and can thus inform flood risk and safety assessments for critical infrastructure. Read more
Bayesian assessment of chlorofluorocarbon (CFC), hydrochlorofluorocarbon (HCFC) and halon banks suggest large reservoirs still present in old equipment Atmospheric Chemistry and Physics DOI 10.5194/acp-22-11125-2022 16 November 2022 Halocarbons contained in equipment continue to be emitted after production has ceased. These “banks” must be carefully accounted for in evaluating compliance with the Montreal Protocol. We extend a Bayesian model to the suite of regulated chemicals subject to banking. We find that banks are substantially larger than previous estimates, and we identify banks by chemical and equipment type whose future emissions will contribute to global warming and delay ozone-hole recovery if left unrecovered. CFC), hydrochlorofluorocarbon (HCFC) and halon banks suggest large reservoirs still present in old equipment">Read more
