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A speleothem collected from Palco Cave (Puerto Rico) spans the 8.2 ka event, a time interval associated with fluctuations of Atlantic Ocean circulation and possible drying in the Caribbean region. While stalagmite δ18O, δ13C, and Mg/Ca data do not show a sustained change in mean state over the 8.2 ka event, the proxies provide robust evidence for three abrupt fluctuations toward drier conditions in rapid succession, each lasting less than two decades, occurring at 8.20, 8.14, and 8.02 ka BP. A cave monitoring program at Palco Cave supports the interpretation of the speleothem proxy records. Because changes in the position of the Intertropical Convergence Zone (ITCZ) are directly coupled to sea-surface temperature variations in the North Atlantic, we hypothesize that cold events in the North Atlantic temporarily limited the northward migration of the ITCZ and tropical rain belt in boreal summer during these abrupt drying periods. The speleothem record suggests that the 8.2 ka event was associated with rapid rainfall fluctuations in the northern Caribbean followed by a comparably warm and wet phase after the 8.2 ka event. This enhanced variability during the transitional period of the deglaciation appears to be linked to a fast coupling between interacting oceanic and atmospheric processes. This involves, in particular, the Atlantic Meridional Overturning Circulation in modulating interhemispheric heat transport. [ABSTRACT FROM AUTHOR]

The sensitivity of tropical Atlantic precipitation patterns to the mean position of the Intertropical Convergence Zone (ITCZ) at different time scales is well‐known. However, recent research suggests a more complex behavior of the northern hemispheric tropical rain belt related to the ITCZ in the western tropical Atlantic. Here we present a precisely dated speleothem multi‐proxy record from a well‐monitored cave in Puerto Rico, covering the period between 46.2 and 15.3 ka. The stable isotope and trace element records document a pronounced response of regional rainfall to abrupt climatic excursions in the North Atlantic across the Last Glacial such as Heinrich stadials and Dansgaard/Oeschger events. The annual to multidecadal resolution of the proxy time series allows substructural investigations of the recorded events. Spectral analysis suggests that multidecadal to centennial variability persisted in the regional hydroclimate mainly during interstadial conditions but also during the Last Glacial Maximum. In particular, we observe a strong agreement between the speleothem proxy data and the strength of the Atlantic meridional overturning circulation, supporting a persistent link of oceanic forcing to regional precipitation. Comparison to other paleo‐precipitation records enables the reconstruction of past changes in position, strength, and extent of the ITCZ in the western tropical Atlantic in response to millennial‐ and orbital‐scale global climate change. Plain Language Summary: It is important to understand the climatic circumstances of how rainfall in the western tropical Atlantic varies under a changing climate to better manage the water supply for millions of people. However, it is not well understood how rainfall varied in the past, especially during the Last Glacial period, a time of strong climate variability and abrupt climate changes. Here, we use a stalagmite from Puerto Rico to create a new record of past changes in rainfall in this region. For this purpose, we analyzed proxy data that reveal a series of wet and dry periods during the Last Glacial corresponding to rapid global climate shifts. Our rainfall‐sensitive stalagmite record captured changes of the tropical rain belt on various timescales and shows that this variability in rainfall is closely connected to changes in the strength of the ocean circulation. This suggests that the link between the ocean and the atmosphere is more robust than previously assumed. The comparison of our record with other rainfall‐sensitive records from Central America and the northern Caribbean allows for a detailed reconstruction of the spatial and temporal changes of the western tropical Atlantic rain belt. Key Points: Puerto Rican speleothem record documents multidecadal to millennial‐scale precipitation variability between 46.2 and 15.3 kaClimate proxies show a distinct rainfall response to abrupt North Atlantic climate change including Heinrich and Dansgaard/Oeschger eventsCompilation of regional precipitation records allows to reconstruct past changes in ITCZ patterns in the western tropical Atlantic [ABSTRACT FROM AUTHOR]

The climate of the western Mediterranean was characterized by a strong precipitation gradient during the Holocene driven by atmospheric circulation patterns. The scarcity of terrestrial paleoclimate archives has precluded exploring this hydroclimate pattern during Marine Isotope Stages 5 to 3. Here we present stable carbon and oxygen isotope records from three flowstones from southeast Iberia, which show that Dansgaard/Oeschger events were associated with more humid conditions. This is in agreement with other records from the Iberian Peninsula, the Mediterranean, and western Europe, which all responded in a similar way to millennial‐scale climate variability in Greenland. This general increase in precipitation during Dansgaard/Oeschger events cannot be explained by any present‐day or Holocene winter atmospheric circulation pattern. Instead, we suggest that changes in sea surface temperature played a dominant role in determining precipitation amounts in the western Mediterranean. Plain Language Summary: Climate events characterized by a sudden temperature increase of up to 10 °C occurring in less than a few decades during the last glacial are recorded in Greenland ice cores. These abrupt warmings, the Dansgaard/Oeschger events, affected large regions of the Northern Hemisphere. The understanding of the regional response in precipitation during these climate shifts is limited for the western Mediterranean, due to the restricted number of terrestrial climate records that cover the last glacial period at sufficient resolution. Speleothems and their stable isotope compositions allow to trace changes in climate and vegetation based on an accurate chronological framework. Here we present a speleothem stable isotope record that shows that the Dansgaard/Oeschger events were associated with increased rainfall and a denser vegetation in the western Mediterranean. A similar pattern was observed for western Europe and other parts of the Mediterranean, and we propose that this was related to generally higher sea surface temperatures of the surrounding oceans rather than a reorganization of atmospheric circulation. Key Points: Western Mediterranean precipitation responded to Greenland interstadials and stadials in a coherent mannerDansgaard/Oeschger interstadials were accompanied by humid climate conditions over the western MediterraneanAtmospheric circulation patterns did not induce spatial differences in precipitation during the last glacial as they did during the Holocene [ABSTRACT FROM AUTHOR]

Stable oxygen and carbon isotope ratios (d13C and d18O) are the most applied climate and environmental proxies in speleothems allowing to infer past changes in cave drip water d13C and d18O related to climate and environmental variations from above the cave. However, disequilibrium isotope fractionation processes can modify d13C and d18O values in speleothems, which is in most cases difficult to estimate due to inter-dependencies on various cave specific parameter. To better understand the effect of these disequilibrium isotope fractionation processes proxy system models were developed in recent years, such as the ISOLUTION model. Here the code of the ISOLUTION model is made available for the public and the speleothem community to be applied to research questions that arise from e.g. monitoring programs that investigate d13C and d18O values of in situ calcite precipitates on watch glasses or modern speleothem calcite, respectively. Another application of the ISOLUTION model is to investigate the dependence of calcite d13C and d18O on the variation of one or multiple cave specific parameter, such as cave air temperature, drip interval, cave air pCO2, Ca2+ concentration of the drip water as well as on relative humidity and wind velocity. This allows to quantitatively estimate the effect of disequilibrium isotope fractionation processes in individual caves and drip sites on speleothem d13C and d18O values for modern and past climates and may help to further elucidate the complex interplay of kinetic and disequilibrium isotope fractionation. [ABSTRACT FROM AUTHOR]

Their amenability to radiometric dating (U-series) makes speleothems (secondary cave carbonate deposits) a key archive of past climatic and environmental changes. However, incorporation of non-radiogenic thorium can hamper U-series dating, and samples older than ca. 600 ka remain out-of-reach for UTh dating. Our aim is to develop isothermal thermoluminescence (ITL) dating as an alternative approach for otherwise undatable samples. The calcite thermoluminescence (TL) signal (280 °C peak) saturates at very high doses (saturation dose up to 5000 Gy) [1,2], which shows great potential to extend the dating limit to several millions of years. However, a spurious TL signal occurring in the high temperature range so far hindered its application [3,4]. The conventional multiple-aliquot additive-dose (MAAD) protocol used for TL dating applies extrapolation for equivalent dose (De) estimation, which is also associated with large uncertainties. ITL dating with the single-aliquot regenerative-dose (SAR) protocol [5,6] might be a promising way to circumvent these issues as it reduces the influence of the spurious TL signal and it applies interpolation to obtain the De. However, this protocol has not been tested yet on samples with independent age control. Here we test the ITL SAR dating protocol on a speleothem sample from Bleßberg cave, Germany, which has been accurately dated by the 230Th/U-method (425.6±3.9 ka to 321.6±2.0 ka, based on 17 dates). An ITL measurement at 235 °C for 200 s can remove the 280 °C TL peak completely without TL contribution from the higher temperature range. The ITL De shows a plateau in the ITL temperature range between 230 °C and 240 °C. Peak shifting and isothermal annealing tests indicate that the 280 °C TL peak and the ITL signal at 235 °C have lifetimes of tens of millions of years at 10 °C, which is sufficiently stable considering the age range of this speleothem sample. The accurate alpha efficiency (a-value) and the U and Th distribution within the sample are measured to estimate the dose rate. The time-dependent dose rate variation due to U-series disequilibrium is corrected for. The ITL ages are compared with the 230Th/U ages to evaluate the performance of the ITL SAR dating protocol. [ABSTRACT FROM AUTHOR]

The connection between climatic change and social response is complex because change articulates a number of inter-related factors. Human decisions are filtered by social buffers – including social memory, risk perception, and cultural priorities – and the rate and scale of climate change is usually much larger than the scale of human decision-making. In this article, we provide information on climate change based on precisely dated speleothems with the response evident in archaeological sites that have radiocarbon date ranges within the same time frame. A stalagmite recovered from within the catchment area for aquifer recharge of the Pre-Arawak site of Angostura in Barceloneta, Puerto Rico, shows that a significant wet period occurred between 3.9 and 3.1 ka (primarily centered at 3.5 ka). We investigate the effect that this increase in precipitation had on the earliest occupations on the island in the context of palaeoenvironmental, geoarchaeological, and archaeological records from Angostura, Maruca, and Paso del Indio. Our analysis suggests the presence of two different adaptation strategies: settlement relocation and microlandscape modification. Our study concludes that the social response to change cannot be seen as monolithic given that human behavior, even within the same period, addresses the needs of individual groups with different priorities. This multiplicity of responses can indeed enhance resilience as social support can continue through alliances and exchanges, strengthening social bonds that can help buffer catastrophes. The results can help shed light on the range of adaptation strategies to change encompassed within the manifestations of social resilience or vulnerability. [ABSTRACT FROM PUBLISHER]

Abstract: We present a speleothem stable oxygen isotope record for the last 12.5ka based on two stalagmites from western Cuba. The δ 18O signal is interpreted to represent past precipitation variability. Both stalagmites show a pronounced transition from higher δ 18O values (indicating drier conditions) to more negative δ 18O values (suggesting wetter conditions) between 10 and 6ka. This transition is also visible in a planktonic δ 18O record off Haiti. On orbital timescales, the δ 18O value of Caribbean precipitation, thus, strongly resembles the oxygen isotope composition of Caribbean surface water. On millenial timescales, the speleothem δ 18O record shows a high correlation to a North Atlantic sea surface temperature (SST) record off West Africa as well as a similarity with the Bond events. Periods of lower North Atlantic SST correspond to less precipitation in the Caribbean and vice versa. The potential teleconnection to the Caribbean may reflect the position of the Intertropical Convergence Zone because a further southward position of the ITCZ leads to reduced precipitation in the northern Caribbean. [Copyright &y& Elsevier]

Abstract: Growth and stable isotope composition of stalagmites are affected by climate changes. To understand the underlying mechanisms, we developed a time dependent multi-box model that describes stalagmite growth and stable isotope fractionation of carbon under disequilibrium conditions. The model takes variations of the drip interval, temperature and the amount of mixing between the impinging drops and the solution on top of the stalagmite into account, which allows to quantify the influence of these parameters. To calculate the variations of δ13C, the multi-box model was calibrated by comparison with an existing growth model. The results show that drip interval, temperature and the mixing coefficient do have a significant influence on δ13C. However, considering the higher natural variability of the drip interval, this parameter might have the largest influence. [Copyright &y& Elsevier]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

The most pronounced climate anomaly of the Holocene was the 8.2 ka cooling event. We present new 230Th/U-ages as well as high-resolution stable isotope and trace element data from three stalagmites from two different cave systems in Germany, which provide important information about the structure and climate variability of the 8.2 ka event in central Europe. In all three speleothems, the 8.2 ka event is clearly recorded as a pronounced negative excursion of the δ18O values and can be divided into a 'whole event' and a 'central event'. All stalagmites show a similar structure of the event with a short negative excursion prior to the 'central event', which marks the beginning of the 'whole event'. The timing and duration of the 8.2 ka event are different for the individual records, which may, however, be related to dating uncertainties. Whereas stalagmite Bu4 from Bunker Cave also shows a negative anomaly in the δ13C values and Mg content during the event, the two speleothems from the Herbstlabyrinth cave system do not show distinct peaks in the other proxies. This may suggest that the speleothem δ18O values recorded in the three stalagmites do not primarily reflect climate change at the cave site, but rather large-scale changes in the North Atlantic. This is supported by comparison with climate modelling data, which suggest that the negative peak in the speleothem δ18O values is mainly due to lower δ18O values of precipitation above the cave and that temperature only played a minor role. Alternatively, the other proxies may not be as sensitive as δ18O values to record this centennial-scale cooling event. This may particularly be the case for speleothem δ13C values as suggested by comparison with a climate modelling study simulating vegetation changes in Europe during the 8.2 ka event. Based on our records, it is not possible to resolve which of these hypotheses is most appropriate, but our multi-proxy dataset shows that regional climate evolution during the event was probably complex, although all δ18O records show a clear negative anomaly. • Three speleothems show pronounced negative peaks in δ18O values during 8.2 ka event. • All records can be divided into a 'whole event' and a 'central event'. • Other proxies show no distinct consistent peaks during the 8.2 ka event. • Magnitude of δ18O peaks can be explained by change in δ18O values of precipitation. • Speleothem δ18O values reflect large-scale changes in the North Atlantic. [ABSTRACT FROM AUTHOR]

Understanding supra-regional climate variability such as the changes in the North Atlantic realm is important to identify the drivers of the climate system. In this study maar lake sediments from the Eifel (western Germany) were analysed with a multi-proxy approach and compared to central and western European speleothem growth phases. C org (chlorins) and the pollen assemblage were analysed from two sediment cores of the Hoher List infilled maar lake. To generate C org (chlorins) and pollen records covering the entire last 130,000 yr b2k (years before year 2000 CE), the data from this study were stacked with published data from other Eifel maar lake sediment cores (Sirocko et al., 2013, 2021, 2022). The sediment cores from Hoher List infilled maar lake were dated by marker tephra layers giving chronological anchor points and the precise dating of the sediment cores was performed by the tuning of the C org (chlorins) records to the NGRIP δ18O record (Rasmussen et al., 2014). The speleothems, whose growth phases are compared to the lake sediment proxy records, were compiled from the literature as well as speleothems from Dechencave (western Germany) dated by the 230Th/U-method in this study. The C org (chlorins) variability shows the bioproductivity in the maar lake, which is related to water temperature and corresponds to the Greenland Interstadials (GIs) in the NGRIP δ18O record indicates its dependence on supra-regional climate variations in the North Atlantic. The pollen record shows three periods of forest with temperate forest species, during the Eemian, early Marine Isotope Stage (MIS) 3, and the Holocene. Speleothem growth in four caves in central and western Europe (Dechencave, Spannagel Cave, Hölloch Cave, Villars Cave) is predominantly sensitive to cold periods with glaciers and/or permafrost conditions above the caves inhibiting speleothem growth. The forested phases and phases of high bioproductivity in the Eifel correspond well with phases of speleothem growth indicating three warm phases in central Europe during the last glacial cycle. [ABSTRACT FROM AUTHOR]

Summary: Monitoring cave environments is important to understand processes in karst systems. If stalagmites from a specific cave are used as archives of past climate variability, a quantitative understanding of the soil–karst–speleothem system is crucial. The monitoring program performed in Bunker Cave (NW Germany), which includes monthly collection of climatological data as well as air and water samples from the cave and the overlying soil since 2006, is a prerequisite for the interpretation of speleothem data from the cave in terms of climate variability. The results show that Bunker Cave is a homogeneously ventilated cave with rather low pCO2 values of 580–1200ppmv, which lacks strong seasonal variations. The δ 18O value of cave drip water reflects the mean annual composition of the rain water, and the seasonal variability is strongly attenuated indicating a well-mixed karst aquifer. Hence, stalagmites from Bunker Cave should be well suited to record interannual/decadal climate trends. Seven drip sites in two cave chambers show three different types of discharge behaviour including slow seasonal drip, fast seasonal drip, and seepage-flow. The drip-rate patterns of most drip sites are consistent with the main infiltration events, taking into account a delay of several months. An instantaneous response to precipitation (i.e., piston-flow) is not observed for any drip site indicating a specific water capacity threshold in the soil/karst aquifer. Prior Calcite Precipitation (PCP) was also identified especially during times of low discharge. Though PCP is not as pronounced at Bunker Cave as in other caves, it probably has an influence on the Mg/Ca ratios of the stalagmites. [Copyright &y& Elsevier]

Abstract Central European climate is strongly influenced by North Atlantic (Westerlies) and Siberian High circulation patterns, which govern precipitation and temperature dynamics and induce heterogeneous climatic conditions, with distinct boundaries between climate zones. These climate boundaries are not stationary and shift geographically, depending on long-term atmospheric conditions. So far, little is known about past shifts of these climate boundaries and the local to regional environmental response prior to the instrumental era. High resolution multi-proxy data (stable oxygen and carbon isotope ratios, S/Ca and Sr/Ca) from two Holocene stalagmites from Bleßberg Cave (Thuringia) are used here to differentiate local and pan-regional environmental and climatic conditions Central Germany through the Holocene. Carbon isotope and S/Ca and Sr/Ca ratios inform us on local Holocene environmental changes in and around the cave, while δ18O (when combined with independent records) serves as proxy for (pan-)regional atmospheric conditions. The stable carbon isotope record suggests repeated changes in vegetation density (open vs. dense forest), and increasing forest cover in the late Holocene. Concurrently, decreasing S/Ca values indicate more effective sulfur retention in better developed soils, with a stabilization in the mid-Holocene. This goes in hand with changes in effective summer infiltration, reflected in the Sr/Ca profile. Highest Sr/Ca values between 4 ka and 1 ka BP indicate intensified prior calcite precipitation resulting from reduced effective moisture supply. The region of Bleßberg Cave is sensitive to shifts of the boundary between maritime (Cfb) and continental (Dfb) climate and ideally suited to reconstruct past meridional shifts of this divide. We combined the Bleßberg Cave δ18O time series with δ18O data from Bunker Cave (western Germany) and a North Atlantic Oscillation (NAO) record from lake SS1220 (SW Greenland) to reconstruct the mean position of the Cfb-Dfb climate boundary. We further estimate the dynamic interplay of the North Atlantic Oscillation and the Siberian High and their influence on Central European climate. Repeated shifts of the Cfb-Dfb boundary over the last 4000 years might explain previously observed discrepancies between proxy records from Europe. Detailed correlation analyses reveal multi-centennial scale alternations of maritime and continental climate and, concurrently, waning and waxing influences of Siberian High and NAO on Central Europe. Highlights • U-series dated multi-proxy speleothem data from Bleßberg Cave, Thuringia cover the Holocene. • Local and pan-regional environmental and climatic changes are reconstructed. • Bleßberg Cave record is compared to data from W Germany and Greenland to infer maritime/continental climate regimes. • Waning/waxing of NAO and Siberian High influence on European climate is discussed for the last 4,000 years. [ABSTRACT FROM AUTHOR]

Reconstructions of last interglacial (LIG, MIS 5e, ∼127–117 ka) climate offer insights into the natural response and variability of the climate system during a period partially analogous to future climate change scenarios. We present well preserved fossil corals ( Diploria strigosa ) recovered from the southern Caribbean island of Bonaire (Caribbean Netherlands). These have been precisely dated by the 230 Th/U-method to between 130 and 120 ka ago. Annual banding of the coral skeleton enabled construction of time windows of monthly resolved strontium/calcium (Sr/Ca) temperature proxy records. In conjunction with a previously published 118 ka coral record, our eight records of up to 37 years in length, cover a total of 105 years within the LIG period. From these, sea surface temperature (SST) seasonality and variability in the tropical North Atlantic Ocean is reconstructed. We detect similar to modern SST seasonality of ∼2.9 °C during the early (130 ka) and the late LIG (120–118 ka). However, within the mid-LIG, a significantly higher than modern SST seasonality of 4.9 °C (at 126 ka) and 4.1 °C (at 124 ka) is observed. These findings are supported by climate model simulations and are consistent with the evolving amplitude of orbitally induced changes in seasonality of insolation throughout the LIG, irrespective of wider climatic instabilities that characterised this period. The climate model simulations suggest that the SST seasonality changes documented in our LIG coral Sr/Ca records are representative of larger regions within the tropical North Atlantic. These simulations also suggest that the reconstructed SST seasonality increase during the mid-LIG is caused primarily by summer warming. A 124 ka old coral documents, for the first time, evidence of decadal SST variability in the tropical North Atlantic during the LIG, akin to that observed in modern instrumental records. [ABSTRACT FROM AUTHOR]

Abstract: Proxy reconstructions of tropical Atlantic sea surface temperature (SST) that extend beyond the period of instrumental observations have primarily focused on centennial to millennial variability rather than on seasonal to multidecadal variability. Here we present monthly-resolved records of Sr/Ca (a proxy of SST) from fossil annually-banded Diploria strigosa corals from Bonaire (southern Caribbean Sea). The individual corals provide time-windows of up to 68years length, and the total number of 295years of record allows for assessing the natural range of seasonal to multidecadal SST variability in the western tropical Atlantic during snapshots of the mid- to late Holocene. Comparable to modern climate, the coral Sr/Ca records reveal that mid- to late Holocene SST was characterised by clear seasonal cycles, persistent quasi-biennial and prominent interannual as well as inter- to multidecadal-scale variability. However, the magnitude of SST variations on these timescales has varied over the last 6.2ka. The coral records show increased seasonality during the mid-Holocene consistent with climate model simulations indicating that southern Caribbean SST seasonality is induced by insolation changes on orbital timescales, whereas internal dynamics of the climate system play an important role on shorter timescales. Interannual SST variability is linked to ocean–atmosphere interactions of Atlantic and Pacific origin. Pronounced interannual variability in the western tropical Atlantic is indicated by a 2.35ka coral, possibly related to a strengthening of the variability of the El Niño/Southern Oscillation throughout the Holocene. Prominent inter- to multidecadal SST variability is evident in the coral records and slightly more pronounced in the mid-Holocene. We finally argue that our coral data provide a target for studying Holocene climate variability on seasonal and interannual to multidecadal timescales, when using further numerical models and high-resolution proxy data. [Copyright &y& Elsevier]

The SISAL database v1 [1] is a comprehensive quality-controlled global compilation of oxygen and carbon isotope records from speleothems spanning large parts of the late Pleistocene compiled as a community effort supported by Past Global Changes (PAGES). The stable isotope records provide information on past changes in climate and the environment, both for reconstruction, as well as for comparison to climate model output.\\The chronology of the majority of the records is based on precise $^\text{230}$Th/U-dating, and speleothems are palaeoclimate archives with generally good chronological control. However, various types of age-depth modelling with different degrees of complexity (e.g., linear interpolation, etc.) have been used to construct the chronologies, and most of the records provide no estimates of age uncertainty. Some data sets have no age model at all. This limits the suitability for assessing abrupt transitions as well as the synchronicity of events across space. \\Here we apply six different age-depth modeling approaches to a representative subset from the SISAL database, to compare and evaluate their suitability as final SISAL chronologies for the next version of the database. The methods include linear models (linear regression, linear interpolation), fitting approaches (StalAge), ensemble-based methods (COPRA), as well as Bayesian models (OxCal, Bacon, Bchron). The subset of records from the SISAL database is representative in a sense that they include speleothems with ''well-behaved'' constant and continuous growth, variable growth rates, age outliers as well as growth interruptions.\\We find that for many speleothems, age models can be established, and that there is an overall consensus on the median, or most likely, age-depth trajectory. Not all methods are applicable in all situations, however, and the resulting confidence intervals differ. We compare and evaluate the methods also by applying them to virtually grown speleothems.\\We discuss challenges that arise (data inconsistencies, missing hiatuses, duplicated sample depths, multi-model integration) and the format we intend for the final chronologies. The new chronologies will allow to consider the impact of age uncertainty on analyses in the SISAL working group consistently across the database.\\[1] Atsawawaranunt \textit{et al}., The SISAL database: a global resource to document oxygen and carbon isotope records from speleothems, Earth Syst. Sci. Data, 10, 1687-1713, https://doi.org/10.5194/essd-10-1687-2018, 2018. [ABSTRACT FROM AUTHOR]