Andes Cryosphere mountain research watercolor comic. Watecolor by Sebastián Martínez Fadic Concept by Sebastián Ruiz-Pereira

I propose that metropolises are the best ‘golden spike’ for the Anthropocene. Based on six selection principles with three ideas, I have identified seven metropolises in seven countries as sites for the Anthropocene’s ‘golden spike’ symbols and museums. I hope that the United Nations will artificially design and build identical Anthropocene’s ‘golden spike’ and museums in these seven metropolises as permanent stratigraphic markers of the Anthropocene.

Agro-climatic zones are geographical areas delineated based on climate homogeneity and impact on agriculture. Ghana's agro-climatic zones have been in use since the 1960s, with no consideration given to current climate change and variability. The continued use of this age-old classified zones suggest Ghana's climate remains stable despite previous research findings to the contrary. In this study, we reconstructed a more appropriate and dis-aggregated agro-climatic zone map of Ghana that is in tandem with the current climate change and variability. Our findings revealed significant changes in the number of climate zones, their boundary sizes and geographical orientation. The newly proposed agro-climatic zones map consist of five distinctive climate regimes namely Sudan Savannah, Guinea Savannah, Transition, Forest and Coastal zones. The Sudan and Guinea Savannah zones showed a southerly expansion. The transition zone shriveled in size as the Guinea Savannah zone took over most of it, notably in the southeast. The forest zone also shrank in size with a northwest shift while the coastal belt grew to encompass the whole coast of Ghana. These changes are strong evidence of climate change and possible food production changes. The findings of this study are useful to agriculture sector in planning their activities, the health sector in predicting specific diseases caused by changes in weather and climate, Ghana Meteorological Agency for weather forecasting purposes, and the National Disaster Management in identifying disaster prone zones.

While the higher mean Equilibrium Climate Sensitivity (ECS) in CMIP6 has been attributed to more positive cloud feedbacks, it is unclear what causes the greater range of ECS values across CMIP6 models compared to CMIP5. Here we investigate the relationship between radiative forcing and cloud feedbacks across the two model generations to explain the very high ECS values in some CMIP6 models. The relationship is sensitive to the definition of the forcing, particularly in CMIP6, but fixed-SST simulations suggest the shortwave cloud feedback ($\lambda_{SW, cl}$) is anti-correlated with the forcing in CMIP5 and weakly positively correlated with the forcing in CMIP6. These relationships reflect the cloud adjustment to the forcing, which is anti-correlated with $\lambda_{SW, cl}$ in CMIP5 and positively correlated in CMIP6. Although we are unable to identify a systematic change across the model generations, we do show that modifications to the land components of climate models are not responsible for the change in the relationship between cloud adjustments and cloud feedbacks, and that cloud adjustments are generally driven by low and, especially mid-level clouds. Moreover, models derived from the MOHC and NCAR modeling centers seem to be responsible for much of the trend between CMIP5 and CMIP6. Our analysis is severely limited by the available simulations, highlighting the need for targeted simulations to probe the sources of intermodel differences in cloud adjustments.

The breakup of the Central Atlantic is known to terminate around 190Myrs while the CAMP (Central Atlantic Magmatic Province) activity was ending. A dense seismic dataset, acquired along the MSG Basin, provide detailed images of the continent-ocean transition and oceanic crust architecture. Five oceanic/magmatic crust facies were described and mapped. They reveal, in the north, a progressive increase of magmatism. In the south, a 9-11 km thick magmatic crust is observed. Locally, a peculiar facies, with intra-oceanic SDR, is observed and correlated with the formation of the African Black Spur Magnetic Anomaly (ABSMA). In the North, seismic data suggest a typical magma-poor margin profile with an extremely thinned continental crust and mantle exhumation at the COT. In the South, the continental crust thinning is associated with SDR emplacement, and a thick magmatic crust emplaced in the distal domain, which is typical of magma-rich margins. Therefore, in the South, the breakup was forced through the continental crust due to the remnant activity of a CAMP derive hotspot. In the North, the magmatic input seems directly linked to the plate motion in the exception of the ABSMA during which, despite a brief and sudden acceleration of the plate motion, an increase of mantle temperature is needed to explain the change in oceanic crust thickness and facies. This evolution emphasizes that the architecture, and thus processes leading to breakup, can vary considering the influence of thermal vertical forces and mechanical horizontal forces, both being necessary for a rift to succeed.

The Southwestern North American (SWNA) megadrought began in 2000 and is now believed to be the driest 22-year period in the region since at least 800 CE. The precipitation deficit during the megadrought (8.3% during 2000-2021) has been accompanied by a significant decrease in gravity waves observed in the upper atmosphere. Prior to the drought (1990-2000), wave-driven temperature fluctuation variances, between 85 and 100 km at Albuquerque and Ft. Collins, were comparable (62.2 K2 and 60.5 K2, respectively), with the largest variances occurring during winter and summer storm seasons. During the first decade of the drought (2001-2010), wave activity above Ft. Collins decreased by 28%, mostly above 94 km, and changed from primarily semiannual to primarily annual variations. These changes may be related to reduced wave generation by tropospheric storms during the megadrought and to an altered geographic distribution of precipitation events in the western and mid-western United States.

The Irminger Sea is one of the few regions in the ocean where deep (> 1000 m) convection occurs. Convection is followed by restratification during summer, when the stratification of the water column is reestablished and the convectively formed water is exported to the lower limb of the Atlantic Meridional Overturning Circulation (AMOC). We investigate the interannual variability and physical drivers of restratification in the upper 600 m of the central Irminger Sea using reanalysis data for the years 1993–2019. We find that there are distinctly different restratification processes in the upper 100 m of the water column (the upper layer) and the water below it (the lower layer). In the upper layer, the stratification is dominated by a strong seasonal cycle that matches the cycle of the surface heat flux. In 2010 and 2019, there were peaks in upper layer stratification, which could be related to strong atmospheric heat and freshwater fluxes. By contrast, in the lower layer the seasonal cycle is weaker and there is strong interannual variability. Restratification can continue for up to 5 months after the surface heat flux has become negative, indicating a role for lateral advection. The strength of the restratification is strongly correlated with the eddy kinetic energy in the eastern Irminger Sea. This suggests the lateral advection is driven by warm, saline eddies from the Irminger Current. In the future, surface warming and freshening of the Irminger Sea due to anthropogenic climate change are expected to increase stratification.

NASA’s InSight seismometer has been recording Martian seismicity since early 2019, and to date, over 1300 marsquakes have been catalogued by the Marsquake Service (MQS). Due to typically low signal-to-noise ratios (SNR) of marsquakes, their detection and analysis remain challenging: while event amplitudes are relatively low, the background noise has large diurnal and seasonal variations and contains various signals originating from the interactions of the local atmosphere with the lander and seismometer system. Since noise can resemble marsquakes in a number of ways, the use of conventional detection methods for catalogue curation is limited. Instead, MQS finds events through manual data inspection. Here, we present MarsQuakeNet (MQNet), a deep convolutional neural network for the detection of marsquakes and the removal of noise contamination. Based on three-component seismic data, MQNet predicts segmentation masks that identify and separate event and noise energy in time-frequency domain. As the number of catalogued MQS events is small, we combine synthetic event waveforms with recorded noise to generate a training data set. We apply MQNet to the entire continuous 20 samples-per-second waveform data set available to date, for automatic event detection and for retrieving denoised amplitudes. The algorithm reproduces all high quality-, as well as majority of low quality events in the manual, carefully curated MQS catalogue. Furthermore, MQNet detects 60% additional events that were previously unknown with mostly low SNR, that are verified in manual review. Our analysis on the event rate confirms seasonal trends and shows a substantial increase in the second Martian year.

The recent spacecraft observations by MMS and Van Allen Probes associated with electromagnetic ion cyclotron waves (EMIC) in the Earth magnetosphere emphasize the important role of multi-ion plasma composition for generation and characteristics of these emissions. We show that main properties of the coherent EMIC waves can be explained with the concept of ‘multi-ion oscillitons’ (Sauer et al., 2001). In a plasma with two types of ions of different masses (e.g. protons and oxygen ions), oscillitons arise from the exchange of momentum and energy between the two ion components, with the electromagnetic field acting as a mediator. At frequencies near cross-over frequencies of different wave modes in the multi-ion plasma the nonlinear resonance which strongly amplifies the seed unstable mode can be excited. A small phase difference in oscillations of different ion species leads to a nonlinear wave beating and generation of wave packets. The ‘resonance ‘ frequency is characterized by a local maximum of the phase velocity and the coincidence of phase and group velocity. It is suggested that the oscillitons are triggered by the instability due to the proton temperature anisotropy and may propagate outside the source region. The generation of coherent waves by oscillitons is of general nature and may contribute to understand the manifold of phenomena in other space plasma environments in which the dynamics of minor ion admixtures cannot be neglected. The concept of oscillitons can also be applied to the momentum exchange between particle groups of the same mass, but different temperature.

As groundwater found in aquifers is the main reservoir of freshwater for human activity, knowledge of the future response of groundwater to climate change is key for improving water management adaptation plans. We analyse the climate-driven evolution of future levels of unconfined aquifers in the 218 world’s major groundwater basins in global climate simulations following the latest IPCC scenarios, run with models able to capture feedbacks among climate, land use and groundwater. We find a rising of groundwater levels on global average, which is consistent with the projected global intensification of precipitation. This signal presents large regional disparities which mostly match the patterns of precipitation changes. As the climate models we used do not simulate human groundwater withdrawals (irrigation as well as domestic and industrial uses) which represent the other main driver of groundwater levels evolution, we also use FAO maps of present-day irrigated areas and projections of population in 2100 to identify regions where groundwater withdrawals could exacerbate the projected depletion, or even reverse a projected rise into a depletion. Depending on the scenario, we then find a rise (respectively a depletion) of groundwater levels in 2100 over 33[28-39]% to 42[41-45]% (respectively 26[25-32]% to 37[36-40]%) of the area covered by the 218 world’s major groundwater basins. And we estimate that 31[29-36]% to 43[42-44]% of the world’s population could be affected by these groundwater changes, facing either water scarcity issues (for 29[27-33]% to 40[39-40]% of the population), or increased risks of flooding (for 1.7[1.5-2.2]% to 2.2[2.2-2.4]% of the population).

Earthquake-triggered slow-moving landslides are not well studied mainly due to lack of high-resolution in-situ geodetic observations both in time and space. Satellite-based interferometric synthetic aperture radar (InSAR) has shown potential in landslides applications, however, it is challenging to detect earthquake-triggered slow-moving landslides over large areas due to the effects of post-seismic tectonic deformations, atmospheric delays, and other spatially propagated errors (e.g., decorrelation noises caused unwrapped errors). Here, we present a novel InSAR phase-gradient-based time-series approach to detect slow-moving landslides that triggered by the 2016 Mw 7.8 Kaikōura earthquake. 21 earthquake-triggered large (> 0.1 km 2) slow-moving landslides are detected and studied. Our results reveal decaying characteristics of the temporal evolutions of these landslides, that averagely after 3.9 years since the earthquake, their postseismic velocity will decay 90% and close to pre-seismic level. Our study opens new perspectives for the research of the mass balance of earthquakes and helps reduce associated hazards.

Communities around the world are increasingly interested in nature-based solutions to mitigation of coastal risks like coastal forests, but it remains unclear how much protective benefits vegetation provides, particularly in the limit of highly energetic flows after tsunami impact. The current study, using a three-dimensional incompressible computational fluid dynamics model with a fluid-structure interaction approach, aims to quantify how energy reflection and dissipation vary with different degrees of rigidity and vegetation density of a coastal forest. We represent tree trunks as cylinders and use the elastic modulus of hardwood trees such as pine or oak to characterize the rigidity of these cylinders. The numerical results show that energy reflection increases with rigidity only for a single cylinder. In the presence of multiple cylinders, the difference in energy reflection created by varying rigidity diminishes as the number of cylinders increases. Instead of rigidity, we find that the blockage area created by the presence of multiple tree trunks dominates energy reflection. As tree trunks are deformed by the hydrodynamic forces, they alter the flow field around them, causing turbulent kinetic energy generation in the wake region. As a consequence, trees dissipate flow energy, highlighting coastal forests reducing the onshore energy flux of tsunamis by means of both reflection and dissipation.

For designing of Ground Source Heating Systems (GSHS) Thermal Response Tests (TRT) are used for a long time. TRTs generally provide a profound basis for the final implementation of a GSHS. They obtain the effective thermal conductivity and thermal resistance of a borehole. Until today several TRT types have been introduced and defined as Geothermal Response Test (GRT), Enhanced GRT (EGRT), Constant Heat Flux TRT (chTRT), Constant temperature (ctTRT ) etc.. These models mainly focus on closed heat exchangers in shallow boreholes. However, recent developments in medium depth drilling technologies make deeper boreholes more economic. Furthermore, advanced methodologies for obtaining thermal conductivities in deep and open boreholes are progressing. In this study, we introduce a new simple thermal conductivity obtaining methodology that can be used for deep and open boreholes. Generally, TRTs are applied with the circulation of water inside pipes or immersing probes in water. In case of water circulation in deep boreholes, different heat flux values will be attributed to different layers. Moreover, by introducing a constant heat flux similar to conventional TRT into water-filled boreholes or water-filled pipes, convective movements of water will occur and thermal conductivities cannot be obtained. However, immersed probes as a heat source might prevent water convection cells inside a pipe or a borehole. In deep boreholes, the heat flux is depended on the thermal conductivity of each layer. Thus, deep boreholes require a discrete heat introduction into every single layer of different thermal conductivity in order to keep the temperature constant. The thermal conductivity of each layer can be approximated and integrated over the total length of a deep borehole. This effect is analytically and numerically investigated in this study.

Resolution plays a major role in the accuracy of wave simulations, and its definition is an important step of wave modelling. It should be chosen taking into consideration the specific goals of each single study, balancing between the need of local space/time skill, the known limits of the employed wind forcing and of the implemented wave physics, and the constraints represented by the available computation resources. In this study we analyzed the effect of wind and wave model resolution on global-scale wave simulations, employing WAVEWATCHIII and wind forcing from CFSR reanalysis and a downscaled CMIP5 model. The resolution of both the model and wind forcing were varied between 0.4 and 1.5°. Decreasing wind resolution alone, without recalibrating the model, leads to negative bias in the simulated significant wave height due to smoother forcing wind peaks. This effect is more than compensated if the wave resolution is reduced, due to the numerical tendency to overestimate wave growth. Improving subscale modelling, which plays a major role in the skill of low-resolution models, leads to significantly better performances in many areas. Although the skill at a resolution of 0.4° is slightly better, the performance at 0.75° and 1.5° is comparable, both in terms of mean and extreme significant wave height. Finally, the impact of resolution (0.75° and 1.5°) on projected waves under a high-warming climate change scenario is not significant. Our results suggest that, unless substantial improvement of atmosphere-ocean dynamics is introduced in the model, lower resolution simulations can be used without major loss of information in studies that focus on global patterns and tendencies, or on overall conditions in large areas.

MESSENGER's exploration of Mercury has revealed a rich and dynamic geological history and provided constraints on the processes that control the planet's internal evolution. That history includes resurfacing by impacts and volcanism prior to the end of the late heavy bombardment and a subsequent rapid waning of effusive volcanism. MESSENGER also revealed a global distribution of thrust faults that collectively accommodated a decrease in Mercury's radius far greater than thought before the mission. Measurements of elemental abundances on Mercury's surface indicate the planet is strongly chemically reduced, helping to characterize the composition and manner of crystallization of the metallic core. The discovery of a northward offset of the weak, axially aligned internal magnetic field, and of crustal magnetization in the planet's ancient crust, places new limits on the history of the core dynamo and the entire interior. Models of Mercury's thermochemical evolution subject to these observational constraints indicate that mantle convection may persist to the present but has been incapable of significantly homogenizing the mantle. These models also indicate that Mercury's dynamo generation is influenced by both a static layer at the top of the core and convective motions within the core driven by compositional buoyancy.

Researchers are challenged with preparing and complying with data management plans and open data mandates. The ocean science repository community has demonstrated the benefits of providing FAIR (findable, accessible, interoperable, and reusable) data to its researchers through innovative alliances, robust metadata, and semantic connectivity. Challenges still exist in coordinating science policy, and research services across funders, institutions, and publishers that support the researcher’s data management needs. The convenors of this session request abstracts that focus on the value of FAIR data to the research community and the tools that support data discovery, compliance with data management plans, transparency, reproducibility, and research integrity.

The left-lateral Enriquillo-Plantain Garden Fault (EPGF) is one of two transform systems that define the Northern Caribbean plate boundary zone. Relative motion across its trace (~ 10 mm/yr) evolves from nearly pure strike-slip in western Haiti to transpressional in eastern Haiti, where the fault system may terminate against a south-dipping oblique reverse fault. Lake Azuei is a large (10 km x 25 km) and shallow (< 30 m deep) lake that lies in the direct extension of the EPGF in eastern Haiti. A single core previously collected in the lake suggests high sedimentation rates at its depocenter (~6 mm/yr). The shallow lake stratigraphy is therefore expected to faithfully record any tectonic deformation that occurred within the past few thousand years. In January 2017, we acquired a grid of high-resolution (~10 cm), shallow penetration (~4 to 5 m) subbottom seismic (CHIRP) profiles spaced 1.2 km apart across the entire lake. A new bathymetric map compiled from these CHIRP data and some prior echosounder survey reveals a flat lake floor (<0.01°) surrounded by steep (~5°) shoreline slopes. The CHIRP profiles highlight several gentle folds that protrude from the flat lakebed near the southern shore, an area where transpressional deformation is presumably focused. Thin (< 20 cm) horizontal strata from the lakebed can be traced onto the flanks of these gentle folds and pinch out in an upward curve. They also often pinch upward onto the base of the shoreline slopes, indicating that young sediments on the lakebed bypassed the folds as well as the shoreline slopes. We interpret this feature as diagnostic of sediments deposited by turbidity currents. The fact that young turbidites pinch out in upward curves suggests that the folds are actively growing, and that active contractional structures (folds and/or blind thrust faults) control much of the periphery of the lake. A few sediment cores were strategically located where beds are pinching out in order to maximize stratigraphic records. Two of these cores successfully penetrated strata imaged by the CHIRP profiles. On-going Pb210 dating of sediment samples from the cores should constrain sedimentation rates and thus help quantify the rates of the tectonic deformation.

To assess the tectonic response of near-field and far-field deformation in the upper plate of a subduction/collision system, we present here a thermochronological study on the subduction related-arc Sanandaj-Sirjan Zone(SSZ) and North Central East Iranian Microcontinent (CEIM), respectively as near-field and far-field of the upper plate of Neo-Tethys subduction margin. Samples have been collected from late Middle Jurassic Kolah-Ghazi granitoid (KGg) (ca. 165-170 Ma) in central SSZ, from Upper Cretaceous Kasf granite (ca. 85-100 Ma) and Paleocene-Eocene Kashmar-Azghand Intrusive Complex (KAIC) (ca. 60-41 Ma) from North Doruneh fault which represents the northern mechanical boundary of CIEM. Time-temperature (T-t) inverse modeling on the ZFT, AFT and AHe data has been performed through HeFTY V1.9 program to constrain the thermal/tectonics history of the SSZ and CEIM. Based on the geological field evidence, some independent T-t constraints such as crystallization ages, stratigraphic unconformities, present-day temperature, have been adopted. The T-t inverse modeling of KGg shows: (i) an early episode of cooling in early Lower Cretaceous, during which the intrusive body has been exhumed to the surface (ii) a burial phase during which the KGg as a whole entered the PAZ in consequence of deposition of the Cretaceous successions, and (iii) a last stage corresponding to final exhumation-related cooling started since the Late Cretaceous-Paleocene boundary. The thermal modeling results of Kasf granite shows (i) an early episode of cooling at Upper Cretaceous-Paleocene during which the intrusive bodies and the hosting units have been exhumed to the surface, (ii) second stage corresponding to a burial phase when the Kasf granite as a whole entered the PAZ in consequence of the deposition of the Paleocene-Eocene succession, and (iii) a last stage corresponding to the final exhumation-related cooling, starting since the middle-late Eocene. The thermal modeling results of KAIC shows (i) an episode of enhanced cooling of KAIC at Eocene-Oligocene boundary, (ii) Second stage is characterized by burial phase to temperatures above the PAZ during the Oligocene, (iii) third stage corresponds to exhumation-related cooling during the early Miocene, and (iv) fourth stage corresponds to a renewed episode of enhanced cooling starting at the Miocene-Pliocene transition, during which the KAIC was finally exposed to the surface. These results document that both hinterland near-field and far-field regions respond contemporaneously to the Neotethyan subduction-related exhumation at the Upper Cretaceous-Paleocene boundary. T-t modeling output for Kasf and KAIC also shows Middle-Late Eocene exhumation-related cooling related to the Middle-Late Eocene Zagros collision- related exhumation. T-t modeling output for KAIC also shows Early Miocene and Late Miocene-Pliocene exhumation-related cooling related to the Early Miocene and Late Miocene-Pliocene Zagros collision-related exhumatio