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The Great Barrier Reef (GBR) is the largest coral reef system on earth, with ecological and scientific importance for the world and economic and iconic value for Australia. However, the characterisation of its offshore wave climate remains challenging because of its remoteness and large dimensions. Here, we present a detailed analysis of the offshore wave climate of the GBR, unveiling the details of both modal conditions and extreme events. We used a calibrated satellite radar altimeter dataset (spanning from 1985 to 2018) to quantify wave climate, assess the influence of climate drivers, and analyse the wave conditions generated by tropical cyclones at three main regions of the GBR (northern, central, and southern). Our results indicate average significant wave heights of 1.6 m, 1.5 m, and 1.7 m for the northern, central, and southern GBR, respectively. The modal wave climate exhibits substantial seasonality, particularly in the northern region with dry season wave heights up to twofold larger than during wet season. The northern and central wave climates show decreasing wave height and wave energy trends over the last 33 yrs, whilst the southern region remains stable. Consistent with prior studies, we found that the wave climate in the southern region is modulated by the El Niño-Southern Oscillation and the southern annular mode, with influence additionally extending to the central region. Analysis of the extreme waves generated by tropical cyclones revealed they generate large, long period waves, frequently above 7 m, resulting in wave power up to 32-fold higher than median conditions.

The contrasted diversification of marine and terrestrial life remains enigmatic. The monotonic expansion of species on continents started later in the early Phanerozoic than in the marine realm, where instead the number of genera waxed and waned. Only a comprehensive evaluation of the changes in the physical environment can provide a unified theory for the long-term pattern of evolution of life on Earth. We developed a numerical model to reconstruct the evolution of the physiography at global scale and high resolution over the entire Phanerozoic eon, accounting for plate tectonics and climatic forcings. Our results point at landscape dynamics as a limiting factor both in lands and oceans, mostly by erosion and sediment transport. Marine diversity was strongly limited by the oscillating bulk riverine sedimentary fluxes that provide nutrients, while the expansion of land plants was hampered until widespread endorheic basins resurfaced continents with a sedimentary cover that facilitated the development of soil-dependent rooted plants. In both realms, landscape dynamics determine the carrying capacity of the environment.

Introduction Sand aprons are ubiquitous depositional sedimentary features that offer insights into the sediment dynamics of coral reef environments. Global studies found that the extent of sand aprons are not related to reef platform size and their widths are a function of environmental factors such as swell period and height, tidal amplitude, latitude, and exposure to wind and waves (Rankey and Garza-Perez 2012). Recent studies using numerical modelling have found that sand aprons in reef flats attain a critical water depth resulting in constant depth (Ortiz and Ashton 2019), and that lagoon infilling through sand apron progradation is a self-limiting process (Rankey 2021). Sand apron progradation is an eco-morphodynamic process and climate change, including intensification and increased frequency of marine heatwaves, ocean and coastal acidification, and changes in wave and tropical storm climates are triggering changes that need to be understood to inform sound management of coral reefs.This paper presents data on the Holocene evolution of the sand aprons on 21 offshore platform reefs located on the southern Great Barrier Reef and how it can be used to infer past wave climates. We then present the recent wave climate for the study area (Smith et al. 2022) and analyse sand apron evolution accordingly. Methods The sand aprons on 21 reefs located on the Capricorn Bunker Group (Southern Great Barrier Reef) were assessed from high-resolution satellite imagery, obtaining digital bathymetric models and digitizing the reef and lagoon contours. We then measured reef area and lagoon area to calculate the percentage of lagoon infilling. The wave climate for the study area was obtained from satellite altimetry using an open-source Python tool (Smith et al. 2020). Preliminary findings Our results showed that the most important factor for lagoon infilling was the size of the reef, with larger reefs typically appearing less infilled than smaller reefs. Wave incidence seemed to be unimportant: the three reefs with less than 50% infill were all medium-sized and exposed to incident waves while all six protected reefs had infilling above 50%. While some authors had pointed out at relative sea-level changes to explain current sand apron stability (Harris et al. 2015), our results show that the self-limiting nature of the sand apron progradation, combined with relative sea-level changes, is a better explanation for sand apron stability. In any case, the extent of the sand apron can be used to infer wave climate at the time of sand apron progradation. For example, for One Tree Reef, one can argue the sand apron could had stopped prograding 4 ka BP because of the self-limiting sediment transport and remained stable until the sea-level fell.The wave climate on the Southern Great Barrier Reef is characterized by significant wave heights (Hs) of 1.7 m and has been stable for the past 33 years (Smith et al. 2022). Future changes in the wave climate, storm frequency, increases in sea level and changes to sediment availability caused by anthropogenic climate change will modify the eco-morphodynamics of the sand aprons and the percentage infilling of the lagoons.

Coral reefs are the most biodiverse and productive ecosystems on Earth. Changes to global climate will alter the conditions required for coral reef survival. In atoll reefs, coral species distribution and survival is determined by waves and tidally induced flows. The outermost part of atoll reefs, the forereef, presents a key morphological control over wave attenuation and consequently nutrient distribution at the scale of entire reefs. These high-energy environments provide protection from the effects of wave inundation to over 200 million people globally. Despite this, the mechanisms of wave transformation over the complex bathymetries of forereefs have received little attention. Here we focus on processes of wave transformation and attenuation by the elongated troughs and depressions typical of forereef slopes known as spurs and grooves (SaGs) and provide a better understanding of the morphodynamics of SaGs. We combine a quantitative morphometric analysis with wave transformation modelling and hydrodynamic field data from One Tree Reef (OTR) of the southern Great Barrier Reef, Australia. We used a 50 cm resolution LiDAR bathymetry dataset and novel methods of morphometric spectral analysis at swell wave exposed, semi-exposed, and protected locations. The wave transformation model, XBeach, was calibrated and validated with published SaG field data and wave data obtained from a 33-year analysis of satellite altimeters. The effects of SaGs on wave energy dissipation were examined under various forecasted climate change scenarios (RCP 2.6, RCP 8.5, and a disaster scenario) to elucidate their role in preventing future coastal hazards. Finally, field data collected from a fourth site on at OTR over a three-day period in October 2022 used an array of two acoustic doppler velocimeters and an 8 Hz pressure transducer. Current and wave measurements were taken in a long (140 m) and deep (max spur height = 5.3 m) groove under typical wave conditions (Hs = 0.8 m, Tp = 7 s). Findings from the numerical models suggest SaGs play a critical role in dissipating wave energy, increasing wave dissipation by bed friction by 75%. Our results demonstrate that a decrease in wave energy dissipation results in an exponential increase in wave overtopping with storm waves producing overtopping > 3 m under worst-case scenarios. Additionally, we found that high bathymetric gradients in SaGs increase dissipation by wave breaking by up to 52% under RCP 8.5, leading to a 71% increase in mean wave energy dissipation despite an 89% reduction in bed friction factor and a 1 m increase in relative sea level. Field observations demonstrate the wave and tide-dominated flow regimes through forereef grooves. Future work aims to investigate the form and process feedbacks in forereef hydrodynamics and consider global to regional scale climate forecasts. To facilitate this, we provide field data and analytical codes open source. Understanding the morphodynamics of forereefs is critical to forecasting reef health, wave transformation, and coastal hazard reductions under climate change conditions.

The distribution of continents and oceans through deep-time has shaped the Earth’s changing climate and geography in a way that is vital for understanding processes ranging from the evolution and migration of living organisms to the distribution of economic mineral deposits, and the precise contribution of anthropogenic CO2 to the present climate. Despite this, producing climate models of an evolving Earth across long periods of geological time have been challenging due to the immense computational resources required, and as a result, deep-time paleo-climate models have tended to focus on single ages. Here we demonstrate the use of an intermediate-complexity atmosphere-ocean Plasim-Genie tool to produce a suite of models that illustrate the evolving climate with evolving continents over hundreds of millions of years.Using this approach, we explore the impact of modelling paleoclimate with a pure paleomagnetic plate reference frame versus a plate motion model that uses a mantle reference frame. These two plate reference frames may have latitudinal differences of up to 15 degrees even in the well-constrained timeframe of the last 100 Myr. We demonstrate with Plasim-Genie that these latitudinal differences result in significant discrepancies in climate in a range of key regions. Users of paleoclimate model data, particularly those studying biology and geography of the past should be aware of the plate reference frame used in generating the climate data. As the Earth’s magnetic field averages to align with the Earth’s spin axis, we suggest that a paleomagnetic reference frame is the preferred reference frame to use for paleoclimate modelling.

The interplay between climate-forced sea-level change, sediment erosion and deposition, and flexural adjustments in deep time on passive margin deltas remains poorly understood. We performed a series of conceptual simulations to investigate flexural isostatic responses to high-frequency fluctuations in water and sediment load associated with climatically driven sea-level changes. We model a large drainage basin that discharges to a continental margin to generate a deltaic depocenter, then prescribe synthetic and climatic-driven sea-level curves of different frequencies to assess flexural response. Results show that flexural isostatic adjustments are bidirectional over 100–1000 kyr timescales and are in sync with the magnitude, frequency, and direction of sea-level fluctuations, and that isostatic adjustments play an important role in driving along-strike and cross-shelf river-mouth migration and sediment accumulation. Our findings demonstrate that climate-forced sea-level changes produce a feedback mechanism that results in self-sustaining creation of accommodation into which sediment is deposited and plays a major role in delta morphology and stratigraphic architecture.

Detrital 10Be from continental river sands or submarine sediments has been extensively used to determine the average long-term denudation rates of terrestrial catchments, based on the assumption that the rate of cosmogenic nuclide production by the interaction of source rocks with cosmic radiation balances out the loss of these nuclides by surface denudation. However, the 10Be signal recorded in sediments may be affected at the source by the response time of mountainous catchments to high-frequency forcings. In addition, transient sediment storage in piedmonts, alluvial plains and lakes or near the coast may also induce a difference between the erosive signal and its record in the sedimentary sink. Consequently, a significant part of the signal recorded in shallow-water sediments can be lost, as deep marine sediments may simultaneously record a signal coming from newly eroded source rocks along with one coming from the destabilization of previously deposited sediments. In this paper, we use the landscape evolution model Badlands to simulate erosion, deposition and detrital 10Be transfer from a source-to-sink sedimentary system (the Var River catchment, southern French Alps) over the last 100 kyr. We first compare model-based denudation rates with the ones that would be extracted from the 10Be record of local continental sediments (equivalent to river sands) and from sediments deposited offshore over time in order to examine if this record provides an accurate estimate of continental denudation rates. Then, we examine which conditions (precipitation rate, flexure, ice cover) satisfy published measured river incision rates and 10Be concentration in submarine sediments. Our results, based on the Var catchment cosmic ray exposure dating and modelling indicate that, while river sands do accurately estimate the average denudation rate of continental catchments, this is much less the case for deep submarine sediments. We find that deep-sea sediments have a different and often much smoother 10Be signature than continental ones and record a significant time lag with respect to imposed precipitation rate changes, representing the geomorphological response of the margin. A model which allows us to fit both measured 10Be concentration in marine sediments and river incision rates on land involves an increase in precipitation rates from 0.3 to 0.7 m yr−1 after 20 ka, suggesting more intense precipitation starting at the end of the Last Glacial Maximum.

Widespread flooding of the Australian continent during the Early Cretaceous, referred to as the Eromanga Sea, deposited extensive shallow marine sediments throughout the Great Artesian Basin (GAB). This event had been considered ‘out of sync’ with eustatic sea level and was instead solely attributed to dynamic subsidence associated with Australia's passage over eastern Gondwanan subducted material. However, mantle convection models previously used to explain this event have since been shown to overestimate dynamic topography amplitude by a factor of two compared with residual topography estimates. Previous models were also based on a Cretaceous eustatic sea level peak at ca. 90 Ma in conventional eustatic sea level curves; however, more recent estimates of global sea level from ocean basin volume (OBV) suggest this peak may have occurred earlier at ca. 120 Ma. Our work links time‐dependent erosion and deposition with dynamic topography and eustasy to test their contribution to basin development using the landscape evolution code pyBadlands. Our results show that the lower amplitude estimates of dynamic topography derived from pseudo‐compressible mantle flow models better reflect the Cretaceous vertical motions of the Australian continent (ca. 100 m) compared with their incompressible counterparts (ca. 200–400 m). Additionally, our models include the Neogene north‐eastward tilting of Australia, elusive in most previously published geodynamic models. In conjunction with an OBV‐derived sea level curve, our preferred landscape evolution model broadly matches the Cretaceous inundation patterns and first‐order sedimentary sequences in the GAB. The results highlight that the Early Cretaceous inundation of the Australian continent is likely a combination of high global sea levels and the regional effects of dynamic subsidence. Our work provides a framework for a new generation of evolving paleogeographic models at continental scales, while also providing key insights into the viability of existing sea level curves and dynamic topography estimates for reproducing topographic and basin evolution.

The rise of a mountain range affects moisture circulation in the atmosphere and water runoff across the land surface, modifying the distribution of precipitation and drainage patterns in its vicinity. Water routing in turn affects erosion on hillslopes and incision in river channels on surrounding mountain ranges. In central Guatemala, two parallel, closely spaced mountain ranges formed during two consecutive pulses of uplift, the first between 12 and 7 Ma (Sierra de Chuacús–Sierra de las Minas), and the second after 7 Ma (Altos de Cuchumatanes). We explore the climatic and tectonic processes through which the rise of the most recent range drove the slowing of river incision and hillslope erosion over the previously uplifted range. The 40Ar/39Ar dating of perched volcanic deposits documents the sequential rise and incision of these mountain ranges. Terrestrial cosmogenic 10Be in river sediments indicates that currently hillslopes in the older range erode more slowly than in the younger range (20–150 vs. 300 m Myr−1). These differences mimic the current distribution of precipitation, with the younger range intercepting the atmospheric moisture before it reaches the older range. River channel steepness and deformation of paleovalleys in the new range further indicate that the younger range has been rising faster than the older range up to today. We review how atmospheric moisture interception and river long-profile adjustment to the rise of the new range have contributed to the decline of erosion rates over the old range. We also explore the consequences of this decline and of aridification on the topographic evolution of the older range. The older range undergoes a slow topographic decay, dominated by backwearing, by the stacking of slowly migrating erosion waves along the mountain flanks, and by the formation of pediments around its base. The morphology of the old range is therefore transitioning from that of a front range to that of a dry interior range.

Continental sedimentation was widespread across the Central Anatolian Plateau in Miocene–Pliocene time, during the early stages of plateau uplift. Today, however, most sediment produced on the plateau is dispersed by a well-integrated drainage and released into surrounding marine depocenters. Residual long-term (106–107 yr) sediment storage on the plateau is now restricted to a few closed catchments. Lacustrine sedimentation was widespread in the Miocene–Pliocene depocenters. Today, it is also restricted to the residual closed catchments. The present-day association of closed catchments, long-term sediment storage, and lacustrine sedimentation suggests that the Miocene–Pliocene sedimentation also occurred in closed catchments. The termination of sedimentation across the plateau would therefore mark the opening of these closed catchments, their integration, and the formation of the present-day drainage. By combining newly dated volcanic markers with previously dated sedimentary sequences, we show that this drainage integration occurred remarkably rapidly, within 1.5 m.y., at the turn of the Pliocene. The evolution of stream incision documented by these markers and newly obtained 10Be erosion rates allow us to discriminate the respective contributions of three potential processes to drainage integration, namely, the capture of closed catchments by rivers draining the outer slopes of the plateau, the overflow of closed lakes, and the avulsion of closed catchments. Along the southern plateau margin, rivers draining the southern slope of the Central Anatolian Plateau expanded into the plateau interior; however, only a small amount of drainage integration was achieved by this process. Instead, avulsion and/or overflow between closed catchments achieved most of the integration, and these top-down processes left a distinctive sedimentary signal in the form of terminal lacustrine limestone sequences. In the absence of substantial regional climate wetting during the early Pliocene, we propose that two major tectonic events triggered drainage integration, separately or in tandem: the uplift of the Central Anatolian Plateau and the tectonic completion of the Anatolian microplate. Higher surface uplift of the eastern Central Anatolian Plateau relative to the western Central Anatolian Plateau promoted more positive water balances in the eastern catchments, higher water discharge, and larger sediment fluxes. Overflow/avulsion in some of the eastern catchments triggered a chain of avulsions and/or overflows, sparking sweeping integration across the plateau. Around 5 Ma, the inception of the full escape of the Anatolian microplate led to the disruption of the plateau surface by normal and strike-slip faults. Fault scarps partitioned large catchments fed by widely averaged sediment and water influxes into smaller catchments with more contrasted water balances and sediment fluxes. The evolution of the Central Anatolian Plateau shows that top-down processes of integration can outcompete erosion of outer plateau slopes to reintegrate plateau interior drainages, and this is overlooked in current models, in which drainage evolution is dominated by bottom-up integration. Top-down integration has the advantage that it can be driven by more subtle changes in climatic and tectonic boundary conditions than bottom-up integration.

The South African landscape displays important lithological and topographical heterogeneities between the eastern, western margins and the plateau. Yet the underlying mechanisms and timings responsible for this peculiar layout remain unclear. While studies have proposed a post-Gondwana uplift driver, others have related these heterogeneities to a more recent evolution induced by deep mantle flow dynamics during the last 30 million years. This theory seems supported by the rapid increase of sediment flux in the Orange basin since the Oligocene. However, the triggers and responses of the South African landscape to dynamic topography are still debated. Here we use a series of numerical simulations forced with Earth data to evaluate the contribution of dynamic topography and precipitation on the Orange river source-to-sink system since the Oligocene. We show that, if the tested uplift histories influence deposits distribution and thicknesses in the Orange sedimentary basin, they poorly affect the large-scale drainage system organisation and only strongly impact the erosion across the catchment for two of the four tested dynamic topography cases. Conversely, it appears that paleo-rainfall regimes are the major forcing mechanism that drives the recent increase of sediment flux in the Orange basin. From our simulations, we find that climate strongly smoothed the dynamic topography signal in the South African landscape and that none of the currently proposed dynamic topography scenarios produce an uplift high enough to drive the pulse of erosion and associated sedimentation observed during the Palaeocene. These findings support the hypothesis of a pre-Oligocene uplift. Our results are crucial to improve our understanding of the recent evolution of the South African landscape.

Sundaland, the inundated shelf separating Java, Sumatra and Borneo from the Malay Peninsula, is of exceptional interest to biogeographers for its species richness and its position at the junction between the Australasian and Indomalay biogeographic provinces. Owing to its low elevation and relief, its physiography is contingent on relative sea-level change, which drove Quaternary species burst in response to flooding episodes. New findings show that the region was predominantly terrestrial during the Late Pleistocene requiring a reassessment of the drivers of its recent biodiversity history. Here we show that physiographic changes have modified the regional connectivity network and remodelled the pathways of species dispersal. From combined landscape evolution and connectivity models, we found four phases of drainage reorganisation and river captures. These changes have fragmented the environment into multiple habitats connected by migratory corridors that cover 8% of the exposed shelf and stretch across the biogeographic provinces. Our results support the theory that rapidly evolving physiography could foster Quaternary biodiversification across Southeast Asia. Physiographic changes such as river catchment drainage reorganisations played an important role in Quaternary species diversification in Sundaland, Southeast Asia, according to simulations using combined landscape evolution and connectivity models.

Species distribution and richness ultimately result from complex interactions between biological, physical, and environmental factors. It has been recently shown for a static natural landscape that the elevational connectivity, which measures the proximity of a site to others with similar habitats, is a key physical driver of local species richness. Here we examine changes in elevational connectivity during mountain building using a landscape evolution model. We find that under uniform tectonic and variable climatic forcing, connectivity peaks at mid-elevations when the landscape reaches its geomorphic steady state and that the orographic effect on geomorphic evolution tends to favour lower connectivity on leeward-facing catchments. Statistical comparisons between connectivity distribution and results from a metacommunity model confirm that to the 1st order, landscape elevation connectivity explains species richness in simulated mountainous regions. Our results also predict that low-connectivity areas which favour isolation, a driver for in situ speciation, are distributed across the entire elevational range for simulated orogenic cycles. Adjustments of catchment morphology after the cessation of tectonic activity should reduce speciation by decreasing the number of isolated regions.

The eSCAPE model is a Python-based landscape evolution model that simulates over geological time (1) the dynamics of the landscape, (2) the transport of sediment from source to sink, and (3) continental and marine sedimentary basin formation under different climatic and tectonic conditions. The eSCAPE model is open-source, cross-platform, distributed under the GPLv3 licence, and available on GitHub (http://escape.readthedocs.io, last access: 23 September 2019). Simulated processes rely on a simplified mathematical representation of landscape processes – the stream power and creep laws – to compute Earth's surface evolution by rivers and hillslope transport. The main difference with previous models is in the underlying numerical formulation of the mathematical equations. The approach is based on a series of implicit iterative algorithms defined in matrix form to calculate both drainage area from multiple flow directions and erosion–deposition processes. The eSCAPE model relies on the PETSc parallel library to solve these matrix systems. Along with the description of the algorithms, examples are provided to illustrate the model current capabilities and limitations. It is the first landscape evolution model able to simulate processes at the global scale and is primarily designed to address problems on large unstructured grids (several million nodes).

Rubble islands are dynamic sedimentary features present on reef platforms that evolve under a variety of morphodynamic processes and controlling mechanisms. They provide valuable inhabitable land for small island nations, critical habitat for numerous species, and are threatened by climate change. Aiming to investigate the controlling mechanisms dictating the evolution of One Tree Island (OTI), a rubble island in the Southern Great Barrier Reef, we combined different remotely-sensed data across varying timescales with wave data extracted from satellite altimetry and cyclone activity. Our findings show that (1) OTI had expanded by 7% between 1978 and 2019, (2) significant gross planform decadal adjustments were governed by the amount, intensity, proximity, and relative position of cyclones as well as El Niño Southern Oscillation (ENSO) phases, and (3) the mechanisms of island growth involve rubble spits delivering and redistributing rubble to the island through alongshore sediment transport and wave overtopping. Frequent short-term monitoring of the island and further research coupling variations in the different factors driving island change (i.e., sediment availability, reef-wave interactions, and extreme events) are needed to shed light on the future trajectory of OTI and other rubble islands under a climate change scenario.

The nature and contribution of flexural isostatic compensation to subsidence and uplift of passive margin deltas remains poorly understood. We performed a series of simulations to investigate flexural isostatic responses to high frequency fluctuations in water and sediment load associated with climatically-driven sea-level changes. We use a parallel basin and landscape dynamics model, BADLANDS, (an acronym for BAsin anD LANdscape DynamicS) that combines erosion, sedimentation, and diffusion with flexure, where the isostatic compensation of the load is computed by flexural compensation. We model a large drainage basin that discharges to a continental margin to generate a deltaic depocenter, then prescribe synthetic and climatic-driven sea-level curves of different frequencies to assess flexural response. Results show that flexural isostatic adjustments are bidirectional over 100-1000 kyr time-scales and mirror the magnitude, frequency, and direction of sea-level fluctuations, and that isostatic adjustments play an important role in driving along-strike and cross-shelf river-mouth migration and sediment accumulation. Our findings demonstrate that climate-forced sea-level changes set up a feedback mechanism that results in self-sustaining creation of accommodation into which sediment is deposited and plays a major role in delta morphology and stratigraphic architecture.

The presence of a mountain affects the circulation of water in the atmosphere and over the land surface. These effects are felt over some distance, beyond the extent of the mountain, controlling precipitation delivery and river incision over surrounding landmasses. The rise of a new mountain range therefore affects the erosion of pre-existing mountains located in close proximity. We document here this phenomenon in the mountains of Central Guatemala. The 40Ar-39Ar dating of lava flows shows that two parallel, closely spaced mountain ranges formed during two consecutive pulses of single-stepped uplift, one from 12 to 7 Ma, and the second one since 7 Ma. The distribution of erosion rates derived from the analysis of detrital cosmogenic 10Be in river sediments shows that the younger range erodes faster (~300 m/My) than the older one (20–150 m/My), and that erosion correlates with the amount of precipitation. Moisture tracking form the Caribbean Sea is intercepted by the younger range, which casts a rain shadow over the older one. The analysis of river long-profiles provides a record of longer-term interactions between the two ranges. The rivers that drain the older range were diverted by the younger range during the early stages of its rise. A few rivers were able to maintain their course across the young range, through profile steepening, but incision completely stalled along their upper reaches, upstream of the younger range. As a result, the older range has been passively uplifted, and entered a phase of a slow topographic decay: pediments have formed along its base, while ancient upstream-migrating waves of erosion, located farther up the mountain flanks, have almost stopped migrating. Aridification and cessation of river incision together explain the slowing down of erosion over the older range. They represent top-down and bottom-up processes whereby the younger range controls erosion over the older one. These controls are regarded as instrumental in the nucleation and enlargement of orogenic plateaus forming above continental accretionary wedges.

As anthropogenic forcing continues to rapidly modify worldwide climate, impacts on landscape changes will grow. Olivine weathering is a natural process that sequesters carbon out of the atmosphere, but is now being proposed as a strategy that can be artificially implemented to assist in the mitigation of anthropogenic carbon emissions. We use the landscape evolution model Badlands to identify a region (Tweed Caldera catchment in Eastern Australia) that has the potential for naturally enhanced supply of mafic sediments, known to be a carbon sink, into coastal environments. Although reality is more complex than what can be captured within a model, our models have the ability to unravel and estimate how erosion of volcanic edifices and landscape dynamics will react to future climate change projections. Local climate projections were taken from the Australian government and the IPCC in the form of four alternative pathways. Three additional scenarios were designed, with added contributions from the Antarctic Ice Sheet, to better understand how the landscape/dynamics might be impacted by an increase in sea level rise due to ice sheet tipping points being hit. Three scenarios were run with sea level held constant and precipitation rates increased in order to better understand the role that precipitation and sea level plays in the regional supply of sediment. Changes between scenarios are highly dependent upon the rate and magnitude of climatic change. We estimate the volume of mafic sediment supplied to the erosive environment within the floodplain (ranging from ∼27 to 30 million m3 by 2100 and ∼78–315 million m3 by 2500), the average amount of olivine within the supplied sediment under the most likely scenarios (∼7.6 million m3 by 2100 and ∼30 million m3 by 2500), and the amount of CO2 that is subsequently sequestered (∼53–73 million tons by 2100 and ∼206–284 million tons by 2500). Our approach not only identifies a region that can be further studied in order to evaluate the efficacy and impact of enhanced silicate weathering driven by climate change, but can also help identify other regions that have a natural ability to act as a carbon sink via mafic rock weathering.

The North Slope of Alaska has experienced a complex tectonic and geodynamic history. Although regional paleogeographic reconstructions for the North Slope of Alaska have been interpreted from the geological record, a process-based understanding of the source-to-sink system accounting for both the landscape and sedimentary basin evolution of the region has not been undertaken. Additionally, the interaction of the complex tectonic and climatic forces and their influence on the development of sedimentary basins is not well understood. We investigate the influence of tectonics (including deep mantle flow), eustasy and isostasy (including flexure) on the source to sink system on the North Slope to better understand its evolution since the Jurassic.We use a quantitative forward modelling approach with the open-source surface evolution code Badlands () which incorporate time-dependent dynamic topography estimates from mantle convection models linking plate motions and mantle flow. We present a new method to implement 3D tectonic displacements (including dynamic topography) in landscape evolution models. The models capture the North Slope’s complex tectonic history and reproduce the sediment depositional trends as observed from the sedimentological record. The spatial variation in dynamic topography through time results in tilting of the basin which influenced sediment routing directions. Sea-level fluctuations significantly slow the depositional system, trapping more sediment in the proximal basin. Cross-sections of the modelled deposition are used to more closely analyse the shelf margin evolution. They reveal that the models reproduce the large-scale stratal geometries observed from the seismic record, as well as the shelf margin trajectory shifts since the Jurassic. This study demonstrates the importance of linking deep Earth processes to landscape evolution models to gain a better understanding of the long-term evolution of sedimentary basins.