Sea Change Research Articles

Spaceborne thermal infrared observations of Arctic sea ice leads at 30 m resolution

Abstract. Sea ice leads play an important role in the heat exchange between the ocean and the overlying atmosphere, particularly narrow leads with widths of less than 100 m. We present a method for detecting sea ice leads in the Arctic using high-resolution infrared images from the Thermal Infrared Spectrometer (TIS) on board the Sustainable Development Science Satellite 1 (SDGSAT-1), with a resolution of 30 m in a swath of 300 km. With the spatial resolution of leads observed by infrared remote sensing increasing to tens of meters, focused on the Beaufort Sea cases in April 2022, the TIS-detected leads achieve good agreement with Sentinel-2 visible images. For the three infrared bands of the TIS, the B2 (10.3–11.3 µm) and B3 (11.5–12.5 µm) bands show similar performance in detecting leads. The B1 band (8.0–10.5 µm) can be usefully complementary to the other two bands, as a result of different temperature measurement sensitivity. Combining the detected results from the three TIS bands, the TIS is able to detect more leads with widths less than hundreds of meters compared to the Moderate Resolution Imaging Spectroradiometer (MODIS). Our results demonstrate that SDGSAT-1 TIS data at 30 m resolution can effectively observe previously unresolvable sea ice leads, providing new insight into the contribution of narrow leads to rapid sea ice changes in the Arctic.

Beyond evidence and reality: the politics, political economy and fallout of hawkish regulatory policy on prescription drugs in Nigeria

PurposeThe purpose of this study is to examine the politics, political economy, and fallout of hawkish regulatory policy on prescription drugs in Nigeria. Hawkish regulatory policy on prescription drug in Nigeria, such as opioid analgesics, is a very complex and multifaceted one, which usually involves the interplay of many factors and parties.Design/methodology/approachPolicy manuals, official government gazettes (legislations, regulations, Acts and decrees), academic literature and a direct ethnographic observation of events surrounding the regulation of prescription drugs were reviewed and engaged.FindingsThe results revealed that Nigerian and global political economy and politics interface to define the direction of the new restrictive opioid policy, with resultant friction between prohibition and consumption. The reviews showed that the overarching “get-tough” and “repressive” policy are not necessarily founded on empirical evidence of an increase in prescription drug sales or use, but more as a product of the interplay of both internal and external politics and the prevailing socioeconomic order.Practical implicationsInstead of borrowing extensively from or being influenced by repressive Western drug laws and perspectives, Nigerian policymakers on prescription opioids should take control of the process by drawing up a home-grown policy that is less intrusive and punitive in nature for better outcomes. A mental sea change is required to understand the intrigues of Western power in Nigeria’s politics and political economy to avoid the continuous symptomatic failure of drug policy.Originality/valueThe politics and economic influence of the United Nations, USA and Western powers, as well as the axiom of moral panic of prescription drugs scares within the Nigerian environment, are particularly significant in the making of the emerging hawkish policy on prescription drugs in Nigeria.

Urban environmental ethics and coastal transformations: remapping the Hauraki Gulf Tīkapa Moana, Auckland, Aotearoa New Zealand, in a process of marine spatial planning

This paper is motivated by recent debates about marine spatial planning (MSP) and a blue economy, pushed worldwide for marine and coastal transitions but discussed by critical scholars as potentially facilitating a neoliberalization of the seas. It engages with an MSP project initiated in Auckland, Aotearoa New Zealand, to formally bargain for a better socionatural state of the Hauraki Gulf Tīkapa Moana (Sea Change Tai Timu Tai Pari, 2013–2016). The paper is interested in the way ethics—proper ways of living—are being problematized and (re)claimed in MSP, and their role in remapping the land/seascape, its socionature and power relations. I employ and develop urban ethics as a research agenda, which draws together a diverse scope of work, in particular post-political theory, neoliberal forms of governing and ethicization, ontological pluralism and (re)centering alternative/non-hegemonic ethicalities. By disentangling the problematizations, naturalcultural imaginaries and governmentalities in 21 in-depth interviews, I identify four distinct but interwoven discursive strands in regard to the MSP. Two strands stand out as they problematize ethics as a means of change. The paper finds transformative potential in a mode of disruption and progressive alternatives to neoliberal beliefs and governmentality, primarily in the (re)centering of non-normative Māori ethicality and knowledge. The paper reveals ethics as a major dimension in environmental bargaining within a neoliberal urban context. Its nuanced understanding of ethics shows ethics’ destabilizing role in environmental bargaining, its role in disrupting power structures and colonizing framings, and in supporting alternative imaginations of socionatural land/sea relations.

Better-constrained climate sensitivity when accounting for dataset dependency on pattern effect estimates

Abstract. The best estimate of equilibrium climate sensitivity (ECS) constrained based on the instrumental record of historical warming becomes coherent with other lines of evidence when the dependence of radiative feedback on the pattern of surface temperature change (pattern effect) is incorporated. Pattern effect strength is usually estimated with atmosphere-only model simulations forced with observed historical sea-surface temperature (SST) and sea-ice change and constant pre-industrial forcing. However, recent studies indicate that pattern effect estimates depend on the choice of SST boundary condition dataset, due to differences in the measurement sources and the techniques used to merge and construct them. Here, we systematically explore this dataset dependency by applying seven different observed SST datasets to the MPI-ESM1.2-LR model covering 1871–2017. We find that the pattern effect ranges from -0.01±0.09 to 0.42±0.10 W m−2 K−1 (standard error), whereby the commonly used Atmospheric Model Intercomparison Project II (AMIPII) dataset produces by far the largest estimate. When accounting for the generally weaker pattern effect in MPI-ESM1.2-LR compared to other models, as well as dataset dependency and intermodel spread, we obtain a combined pattern effect estimate of 0.37 W m−2 K−1 [−0.14 to 0.88 W m−2 K−1] (5th–95th percentiles) and a resulting instrumental record ECS estimate of 3.2 K [1.8 to 11.0 K], which as a result of the weaker pattern effect is slightly lower and better constrained than in previous studies.

Multi-proxy evidence of unprecedented hydroclimatic change in a high Arctic proglacial lake: Linnévatnet, Svalbard

ABSTRACT Svalbard is at the forefront of sea ice, marine, and terrestrial environmental change in the Arctic and so can be viewed as an example of what may be expected in other high latitude regions influenced by the North Atlantic Current. However, there are few highly resolved (subdecadal) paleoclimate records from this area that provide a long-term perspective on recent climatic changes. Here, we investigate a new composite sedimentary sequence from Linnévatnet, western Spitsbergen, spanning the last ~2,000 years. The chronology of this new composite laminated sequence is supported by four radiometric dates. Prior to conducting paleoclimate investigations on these lake sediments, we investigated the sediment sources entering Linnévatnet. Sediment samples collected around the lake’s watershed indicate that the main sediment sources come from the eastern carbonate valley wall as well as Linnéelva, the main river system. Micro-X-ray fluorescence (µ-XRF) results indicate that calcium is the largest component of sediment delivered to the delta-proximal basin, where the sedimentary record was collected. Percentage organics deduced from loss-on-ignition measurements reveal an antiphased relationship with calcium and magnetic susceptibility, implying that the sediment loading at the core site is largely modulated by the alternation of calcium derived from carbonates of the eastern flanks of the valley and by coal-bearing sandstone from Linnéelva, derived from the main river inflow that drains the central valley. Linnéelva is mainly fed by snow and glacier meltwaters from Linnébreen, the small valley glacier now located 7 km south of Linnévatnet. Because Linnébreen is underlain by coal-bearing sandstone, organic content in Linnévatnet lake sediments can be used as an indicator of glacier activity. Annually resolved parameters—that is, calcium and grain size—were found to be strongly correlated to temperature inferred from nearby Lomonosovfonna δ18O ice record as well as the wider reconstructed Northern Hemisphere winter temperature. The coarsest grain size, highest calcium values, and lowest concentration of organics occurred just in recent years, suggesting that glacier influence on the sedimentary input to Linnévatnet is now at an all-time low in the context of the past millennia.

The Effects of Discharge Changes in Siberian Rivers on Arctic Sea-Ice Melting

Arctic river discharge is one of the important factors affecting sea-ice melting of Arctic shelf seas. However, such effects have not been given much attention. In this study, the changes in discharge of the Ob, Yenisei, and Lena Rivers and the sea ice of the Kara and Laptev Seas during 1979–2019 were analyzed. Substantial increases in discharge and heat from the discharge and decreases in sea ice concentration (SIC) were detected. The effects of changes in discharge and riverine heat on sea ice changes were investigated. The results showed that the influence of the discharge, accumulated discharge, heat, and accumulated heat on SIC mainly occurred at the beginning and final stages of sea-ice melting. Discharge accelerated the melting of sea ice by increasing the absorption of solar radiation as the impurities contained in the discharge washed to the sea ice surface during the initial and late stages of sea-ice melting. Changes in cumulative riverine heat from May to September greatly contributed to the SIC changes in the Kara and Laptev Seas at the seasonal scale. The SIC reduced by 1% when the cumulative riverine heat increased by 213.2 × 106 MJ, 181.5 × 106 MJ, and 154.6 × 106 MJ in the Lena, Yenisei, and Ob Rivers, respectively, from May to September. However, even in the plume coverage areas in the Kara and Laptev Seas, discharge changes from the three rivers had a limited contribution to the reduction in SIC at annual scales. This work is helpful for understanding the changes in Arctic sea ice.

Increased sensitivity of sea urchin larvae to metal toxicity as a consequence of the past two decades of Climate Change and Ocean Acidification in the Mediterranean Sea

The Mediterranean Sea represents a natural laboratory to infer the possible impacts of climate change and ocean acidification. In this article, we report the deteriorating ability of sea urchin larvae (Paracentrotus lividus) to cope with toxicity of a reference contaminant (Cu EC50) over the past 20 years and assessed the influence of 5 environmental factors from satellite measurements. This timeframe was divided in before and after January 2016 (46.57 μg/L vs 28.56 μg/L respectively, p < 0.001). In the second subset of data, correlation of the biological variable with CO2 and pH strengthened compared to the first part (rCO2-EC50: −0.21 vs −0.83 and rpH-EC50: 0.25 vs 0.87 respectively), with a causal link starting from one year and ending 4 months prior to EC50 measurements. Considering the continuous increase in CO2 concentrations recorded recently, this study could reveal a rapid deterioration of the health condition of this population of sea urchins in a coastal ecosystem.

DynIceData: a gridded ice–water classification dataset at short-time intervals based on observations from multiple satellites over the marginal ice zone

ABSTRACT High-resolution observations of short-term changes in sea ice are critical to understanding ice dynamics and also provide important information used in advice to shipping, especially in the Arctic. Although individual satellite sensors provide periodic sea ice observations with spatial resolutions of tens of meters, information regarding changes that occur over short time intervals of minutes or hours is limited. In this study, a gridded ice–water classification dataset with a high temporal resolution was developed based on observations acquired by multiple satellite sensors in the Marginal Ice Zone (MIZ). This dataset – DynIceData – which combines Sentinel-1 Synthetic Aperture Radar (SAR) data with Gaofen-3 (GF-3) SAR and SDGSAT-1 thermal infrared imagery was used to obtain observations of the MIZ with a range of temporal resolutions ranging from minutes to tens of hours. The areas of the Arctic covered include the Kara Sea, Beaufort Sea, and Greenland Sea during the period from August 2021 to August 2022. Object-oriented segmentation and thresholding were used to obtain the ice–water classification map from Sentinel-1 and GF-3 SAR image pairs and Sentinel-1 SAR and SDGSAT-1 thermal image pairs. The time interval between the images in each pair ranged from 1 minute to 68 hours. Ten-kilometer grid sample granules with a spatial resolution of 25 m for the GF-3 SAR data and 30 m for the SDGSAT-1 thermal data were used. The classification was verified as having an overall accuracy of at least 95.58%. The DynIceData dataset consists of 7338 samples, which could be used as reference data for further research on rapid changes in sea ice patterns at different short time scales and provide support for research on thermodynamic and dynamic models of sea ice in combination with other environmental data, thus potentially improving the accuracy of sea ice forecasting using Artificial Intelligence. The dataset can be accessed at https://doi.org/10.57760/sciencedb.j00001.00784.

Queer Politics of Naming and Figuration of the “Lesbian” in Maja Ma

In post-377 neoliberal India, with the emergence and proliferation of subscription-based video streaming platforms, the cultural field has undergone a sea change. In this complex, shifting, and evolving cultural terrain, representation of queer/lesbian women is becoming less uncommon. Maja Ma contributes to this growing cultural landscape by offering the representation of a “lesbian” who is also a Hindu mother, aunty, and wife. In this paper, I explore what the politics of naming—which has largely been avoided by films committed to the representation of queer women in Hindi cinema—offers the film’s “lesbian” protagonist, what it reveals about her complex figuration as aunty-mother-wife, and what naming offers relationalities that are forged, informed, and altered by the private disclosure as well as public revelation of her queerness. Drawing on queer cultural studies scholarship focused on India, as well as scholarship on the complexities of “lesbian” activism in India, I interrogate the shift that Maja Ma engenders in Indian queer cultural landscape, and the queer possibilities it offers this field, while paying attention to dominant norms of representation it aligns itself with.

Soil Moisture Influences on Summer Arctic Cyclones and Their Associated Poleward Moisture Transport

Abstract Moisture transport into the Arctic is an important modulator for clouds, radiative forcing, and sea ice change. Transport events—namely, moist-air intrusions—are often associated with Arctic cyclones, and during the summer season we find that the high-latitude land surface is a significant moisture source for intrusions. Summer Arctic cyclones typically originate from the surrounding continental interior and shorelines where during the early stages of intensification the warm sector experiences strong latent heat fluxes from the land surface. In this study, we use multiyear reanalysis data and back-trajectory calculations to quantify the linkages between key continental moisture source regions and water vapor within cyclone-induced intrusions. We also conduct regional soil moisture sensitivity experiments using the Coupled Ocean–Atmosphere Mesoscale Prediction System (COAMPS) to diagnose the land surface moisture contribution for an August 2016 Arctic cyclone case. Results from reanalysis show that land regions on average account for more than 30% of the total moist-air intrusion flux at 70°N during summer. COAMPS case-study experiments reaffirm this result, showing that land surface moisture flux on average accounts for 30% of the intrusion water vapor content. COAMPS experiments further reveal that land surface moisture impacts cyclone intensification and moist-air intrusion cloud water vapor. When the regional soil moisture is reduced, intrusion cloud cover is also reduced, resulting in an increase in the surface solar radiation &gt; 90 W m−2. These results demonstrate that the high-latitude land surface plays an important role in the Arctic summer hydrological cycle and may be increasingly impactful as traditionally cold or frozen soils warm. Significance Statement The purpose of this study is to better understand to what extent high-latitude land surface moisture flux is entrained into summer Arctic cyclones and their poleward moisture transport. Moisture transport into the Arctic is important for regional clouds, radiative forcing, and sea ice change. Our results show that land surface evaporation augments cyclone-induced moisture transport into the Arctic on average by 30%. Results are important because traditionally cold or partially frozen high-latitude soils continue to warm and exhibit more positive evaporative trends, including areas undergoing permafrost thaw.

Alaska Terrestrial and Marine Climate Trends, 1957–2021

Abstract Some of the largest climatic changes in the Arctic have been observed in Alaska and the surrounding marginal seas. Near-surface air temperature (T2m), precipitation (P), snowfall, and sea ice changes have been previously documented, often in disparate studies. Here, we provide an updated, long-term trend analysis (1957–2021; n = 65 years) of such parameters in ERA5, NOAA U.S. Climate Gridded Dataset (NClimGrid), NOAA National Centers for Environmental Information (NCEI) Alaska climate division, and composite sea ice products preceding the upcoming Fifth National Climate Assessment (NCA5) and other near-future climate reports. In the past half century, annual T2m has broadly increased across Alaska, and during winter, spring, and autumn on the North Slope and North Panhandle (T2m &gt; 0.50°C decade−1). Precipitation has also increased across climate divisions and appears strongly interrelated with temperature–sea ice feedbacks on the North Slope, specifically with increased (decreased) open water (sea ice extent). Snowfall equivalent (SFE) has decreased in autumn and spring, perhaps aligned with a regime transition of snow to rain, while winter SFE has broadly increased across the state. Sea ice decline and melt-season lengthening also have a pronounced signal around Alaska, with the largest trends in these parameters found in the Beaufort Sea. Alaska’s climatic changes are also placed in context against regional and contiguous U.S. air temperature trends and show ∼50% greater warming in Alaska relative to the lower-48 states. Alaska T2m increases also exceed those of any contiguous U.S. subregion, positioning Alaska at the forefront of U.S. climate warming. Significance Statement This study produces an updated, long-term trend analysis (1957–2021) of key Alaska climate parameters, including air temperature, precipitation (including snowfall equivalent), and sea ice, to inform upcoming climate assessment reports, including the Fifth National Climate Assessment (NCA5) scheduled for publication in 2023. Key findings include widespread annual and seasonal warming with increased precipitation across much of the state. Winter snowfall has broadly increased, but spring and autumn snowfalls have decreased as rainfall increased. Autumn warming and precipitation increases over the North Slope, in particular, appear related to decreased sea ice coverage in the Beaufort Sea and Chukchi Seas. These trends may result from interrelated processes that accelerate Alaska climate changes relative to those of the contiguous United States.

"Bau Nyale " from the perspective of Science, Local Wisdom and Ecotourism

Bau Nyale is an annual tradition of the Sasak people in Central Lombok, which is celebrated every year on the 20th of the 10th month according to the Sasak calendar. This tradition comes from a legend that lives in society about the sacrifice of a princess to maintain the peace and unity of her country. Through a multidisciplinary approach that combines the perspectives of science and ecotourism sustainability, this study aims to present a comprehensive understanding of the Nyale legend and phenomenon and their associated ecotourism implications. This research method includes a literature study, field observations and interviews. The results of this study provide a deeper understanding of the legend of Princess Mandalika, the Bau Nyale phenomenon, and the related ecotourism implications. It was found that Nyale rituals have significant ecological and social impacts, including potential reductions in Nyale sea worm populations and changes to local culture. Therefore, sustainable ecotourism management is needed to ensure the sustainability of this phenomenon in the long term. This research has important implications in cultural preservation and environmental conservation. It is hoped that this study can contribute to an understanding of the interaction between cultural traditions and ecotourism and become a basis for developing sustainable management strategies in the context of the Bau Nyale phenomenon.

Deconstructing the causes of July sea level variability in the East Sea from 1994 to 2021

In 2021 the East Sea experienced its highest July sea level (65.09 cm), as well as the highest July sea surface and atmospheric temperatures, in the 29 years between 1993 and 2021. We present several methodologies to identify the more important causes of sea level change (SLC) in a semi-enclosed sea and explore the critical fluctuation of ocean mass transport divergence during a period of rapid sea level rise. Based on satellite altimeter data in the East Sea, the SLC, as reflected in the absolute dynamic topography (ADT), which is the ADT difference between the last and first days of a month, was 7.18 cm in July 2021. This may reflect a combination of oceanic and atmospheric factors: ocean heat transport divergence among the Korea, Tsugaru, and Soya Straits was found to contribute 2.32 cm of SLC, atmospheric heat flux at the sea surface contributed 2.87 cm of SLC, and mass divergence (including errors) accounted for 1.98 cm of SLC. The monthly mean sea level (ADT) variation in the East Sea should be examined in terms of the oceanic and atmospheric fluxes, and the SLC sources can additionally be divided into heat and others (mass + errors). The proportional contribution of heat to SLC from 1994 to 2021 was 97.4%. Although the contributions of mass and errors were small, there were substantial temporal fluctuations, as their standard deviation reached up to 96.7% of that of SLC in ADT. In the near future, a more precise analysis of the contributions of mass and errors to SLC is required.

Ozone Monitoring Instrument (OMI) UV aerosol index data analysis over the Arctic region for future data assimilation and climate forcing applications

Abstract. Due to a lack of high-latitude ground-based and satellite-based data from traditional passive- and active-based measurements, the impact of aerosol particles on the Arctic region is one of the least understood factors contributing to recent Arctic sea ice changes. In this study, we investigated the feasibility of using the ultraviolet (UV) aerosol index (AI) parameter from the Ozone Monitoring Instrument (OMI), a semi-quantitative aerosol parameter, for quantifying spatiotemporal changes in UV-absorbing aerosols over the Arctic region. We found that OMI AI data are affected by an additional row anomaly that is unflagged by the OMI quality control flag and are systematically biased as functions of observing conditions, such as azimuth angle, and certain surface types over the Arctic region, resulting in an anomalous “ring” of climatologically high AI centered at about 70∘ N, surrounding an area of low AI over the pole. Two methods were developed in this study for quality-assuring the Arctic AI data. Using quality-controlled OMI AI data from 2005 through 2020, we found decreases in UV-absorbing aerosols in the spring months (April and May) over much of the Arctic region and increases in UV-absorbing aerosols in the summer months (June, July, and August) over northern Russia and northern Canada. Additionally, we found significant increases in the frequency and size of UV-absorbing aerosol events across the Arctic and high-Arctic (north of 80∘ N) regions for the latter half of the study period (2014–2020), driven primarily by a significant increase in boreal biomass-burning plume coverage.

Century‐scale sequences and density‐flow deltas of the late Holocene and modern Dead Sea coast, Israel

ABSTRACTLate Holocene Dead Sea rift‐margin strata reveal century‐scale sequences. Sequences are known to form at millennial timescales, but whether they can form at scales as short as centuries (seventh‐order, sensu Vail et al., 1991) was previously unconfirmed. This study maps lithofacies and sequence‐stratigraphic surfaces from a ca 35 m high outcrop of the post‐1500 ad part of the Holocene falling‐stage wedge, and adjacent subaerial environments, along the Nahal Darga of the western Dead Sea coast, using drone images. The study also produces the first maps of subaqueous delta environments from remotely operated vehicle photographs. Comparison of outcrop and remotely operated vehicle data show that delta foresets form by debris‐flow lobes accreting onto the delta face. Debris lobes increase in size with depth, have sorted cobble heads, and stack compensationally. Debris lobes dewater to form mostly erosive turbidity currents that cut channels and obstacle scours down slope. Topsets comprising fluvial, beach‐ridge and lagoonal deposits prograde over these foresets. Surfaces separating foreset and topset elements of this Gilbert‐delta system bind systems tracts and record downstep and upstep of the shoreface associated with base‐level rises and falls. These surfaces match known lake‐level changes in the Dead Sea in magnitude, timing and direction. They confirm Medieval (ca 600 to 1300 ad) and Modern (ca 1300 ad to Modern) century‐scale sequences. These microsequences form in the Dead Sea because this climate‐sensitive lake can generate metres‐scale lake‐level cycles on century timescales, and because depositional systems can, as shown here, reestablish sufficiently rapidly (≤101 years) to record century‐scale cycles with complete systems tracts. Although conditions for generating microsequences are optimal in the Dead Sea, they are not unique. These microsequences pose a challenge to sequence stratigraphy because they typically fall below seismic resolution, may geometrically resemble higher‐order composite sequences and complicate defining of anchor sequences within a sequence hierarchy.

The global change and response special project: using remote sensing data to monitor and invert key components in the cryosphere

It is critical to understand the mechanisms and impacts of global climate change in cryosphere and polar environment. Here we describe the design and progress of the remote sensing products we have developed to monitor these changes. We obtain datasets by combining multi-sensor remote sensing systems with field validation systems, and then develop a methodological system that combines multiple sources and calibration technologies to address the challenges of data heterogeneity in dynamically monitoring key parameters. This global change and response special project supported by the National Key Research and Development Program of China, named “observation and inversion of critical parameters of changes in the cryosphere and polar environment”, providing comprehensive records of essential elements of the cryosphere through long-term satellite records. The multi-team is completing the project and collecting data from multi-sensor to create remote sensing data products that include records of changes in the cryosphere, such as permafrost, glaciers, ice sheet mass balance, seasonal snow accumulation, sea ice, and albedo changes. Finally, the existing ground- and space-based observing system can be improved to provide dynamic monitoring of key parameters in the cryosphere and changes in the polar environment.

Model based estimation of climate change impacts on the drainage demand of low lying coastal areas in Northwest Germany along the North Sea

Study regionThe Northwest German part of the North Sea coast Study focusLow lying coastal areas are highly threatened by climate change. This is due to rising sea level and changing water balance caused by climate change. Adaptation of coastal protection and inland drainage to climate change requires precise predictions of future conditions. While information on sea level rise is globally available, coastal water balance projections need to be specific for regions where often no discharge data is available. To serve this demand, a model based scenario analysis was carried out for four water boards in Northwest Germany. These water boards are regional organisations responsible for drainage and surface water level regulation in marsh areas. A water balance model was calibrated and validated against data of pumping stations and tidal water gates. Subsequently, climate change impacts on runoff generation were estimated. New hydrological insights for the regionThe results indicate that runoff generation is expected to increase significantly in the wet season, same as the frequency of periods with large runoff volumes. The climate change impact signal is consistent over all investigated water board areas, indicating that the climate change signal dominates the spatial variability in soil properties and land use. The results emphasize the necessity to consider runoff generation projections for adjusting coastal drainage management. The scenario projections can be directly used for regional adaptation planning processes, taking into account the underlying uncertainties.

Middle Paleocene-early Eocene inter-regional correlations and palaeoclimatic changes in eastern Tethys Sea: Calcareous nannofossil evidence for Paleocene-Eocene Thermal Maximum (PETM) and sea-level change from the western Tarim Basin, NW China

Calcareous nannofossil assemblages from the interval covering the middle Paleocene to early Eocene (P/E), studied in sediments from two sections located in the western Tarim Basin (Kuzigongsu and Bashibulake), indicate that the record of the PETM (Paleocene-Eocene Thermal Maximum) is inscribed in a transgression-regression cycle. A large sea transgression occurred concomitant to the Qimugen Formation, according to earlier studies. Here we present detailed evidence of richness and abundance of calcareous nannofossils to study the PETM and sea-level change in the western Tarim Basin. The gradually increasing sea level from the base of the Qimugen Formation is dated to the nannofossil zones NP7 to 9a (Thanetian), in which the first occurrences of H. riedelii and of D. multiradiatus have been recorded. The highstand of the sea level cycle coincides with increasing Discoaster spp. amounts near the Paleocene/Eocene boundary (NP9a-10), which is dated by the occurrence of RD assemblages (namely, Rhomboaster spp. and Discoaster araneus group). Evidence of regression, observed in the top of Qimugen Formation (NP10–11) corresponds to low abundance and diversity of nannofossils, and is characterized by a rapid increase of Micrantholithus spp. in the assemblage. Inter-regional correlations between the two sections show that in the Tianshan Mountain area the highest relative sea level occurred near the middle part of NP9a.

Slowdown of Antarctic Bottom Water export driven by climatic wind and sea-ice changes

Antarctic Bottom Water (AABW) is pivotal for oceanic heat and carbon sequestrations on multidecadal to millennial timescales. The Weddell Sea contributes nearly a half of global AABW through Weddell Sea Deep Water and denser underlying Weddell Sea Bottom Water that form on the continental shelves via sea-ice production. Here we report an observed 30% reduction of Weddell Sea Bottom Water volume since 1992, with the largest decrease in the densest classes. This is probably driven by a multidecadal reduction in dense-water production over southern continental shelf associated with a >40% decline in the sea-ice formation rate. The ice production decrease is driven by northerly wind trend, related to a phase transition of the Interdecadal Pacific Oscillation since the early 1990s, superposed by Amundsen Sea Low intrinsic variability. These results reveal key influences on exported AABW to the Atlantic abyss and their sensitivity to large-scale, multidecadal climate variability.

“Pillar-Biters” and Beyond

Abstract A common motif in late medieval and early modern Northern European art is the “pillar-biter.” Usually, the pillar-biter is depicted as a man who clings to a column while biting into it, but there are also representations of men and women who embrace or kiss columns. In the iconographic literature, the motif is usually linked to religious hypocrisy and the dissimulation of piety. But why did premodern Europeans associate columns and pillars with religious hypocrisy? To answer this question, the essay explores the pillar-biter motif in four different contexts: visual and linguistic traditions; ecclesiastical discourses and theology; popular piety and material religion; and, lastly, the sea change brought about by the Reformation. The column may seem a mere architectural element to the modern eye, but premodern viewers associated it with a host of religious practices and controversies that have fallen into oblivion.