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As the construction sector is one of the most carbon-intensive and resource-intensive industries, the necessity for a transition from a linear to a circular economy is widely acknowledged. Aimed at facilitating the transition, several policy frameworks, operational tools and assessment instruments have been developed in recent decades. Nevertheless, the integration of circularity in the construction sector remains constrained and haphazard, frequently focusing solely on the production phase and neglecting the comprehensive impacts within the overall process. The detected gap between theoretical framework and practical implementation is reflected by the limited coordination between policies and tools, which creates a significant obstacle to the adoption of consistent and effective practices. A dual analysis is conducted, comprising two parallel domains: an investigation of a circular policy theoretical framework in urban environments through a literature review, and an analysis of practice-oriented tools through resilience assessment and green building rating systems. As a result, common ground and shared targets are identified between the two scopes, as well as contrasts and inconsistencies that require further attention. These are classified according to their role as barriers or drivers of change, and recommendations for synergistic improvement between policies and tools are provided. [ABSTRACT FROM AUTHOR]

Two major barriers hinder the holistic understanding of subsurface critical zone (CZ) evolution and its impacts: (a) an inability to measure, define, and share information and (b) a societal structure that inhibits inclusivity and creativity. In contrast to the aboveground portion of the CZ, which is visible and measurable, the bottom boundary is difficult to access and quantify. In the context of these barriers, we aim to expand the spatial reach of the CZ by highlighting existing and effective tools for research as well as the "human reach" of CZ science by expanding who performs such science and who it benefits. We do so by exploring the diversity of vocabularies and techniques used in relevant disciplines, defining terminology, and prioritizing research questions that can be addressed. Specifically, we explore geochemical, geomorphological, geophysical, and ecological measurements and modeling tools to estimate CZ base and thickness. We also outline the importance of and approaches to developing a diverse CZ workforce that looks like and harnesses the creativity of the society it serves, addressing historical legacies of exclusion. Looking forward, we suggest that to grow CZ science, we must broaden the physical spaces studied and their relationships with inhabitants, measure the "deep" CZ and make data accessible, and address the bottlenecks of scaling and data‐model integration. What is needed—and what we have tried to outline—are common and fundamental structures that can be applied anywhere and used by the diversity of researchers involved in investigating and recording CZ processes from a myriad of perspectives. Plain Language Summary: The "critical zone" is the zone of the Earth from treetops to belowground water. It is where crops are grown, water is drawn for drinking and industry, and waste generated by humans ends up. Understanding how deep this section of the Earth is, and how it is changing, is key to being able to determine how impactful changes in land use or climate will be to human systems. That said, it is difficult to get below‐ground information, and scientists in different subfields of the Earth sciences define the depth of the critical zone differently. Here, we describe the tools and language we use to make those decisions. We also note that Earth scientists are not a diverse group, which means we miss out on the ideas, solutions, and impacts that those from historically excluded groups might have to address the big problems humans must solve. To advance critical zone science, we need to broaden the physical areas we study, access to these sites, and the inclusion and sense of belonging of people studying them. We also need to measure deep into the Earth where we can, make our data accessible, and tackle scientific obstacles in integrating data and models. Key Points: CZ depth is defined by multiple processes key to human existence, yet is undermeasured and thus poorly understoodScientific jargon can make defining and communicating CZ processes difficult to stakeholders and even scientists in other fieldsLegacies in western science, upon which CZ science is based, can be countered to promote progress in the Earth sciences [ABSTRACT FROM AUTHOR]

Feedbacks between climate, erosion and tectonics influence the rates of chemical weathering reactions (1,2), which can consume atmospheric C[O.sub.2] and modulate global climate (3,4). However, quantitative predictions for the coupling [...]

We explore how rock properties and channel morphology vary with rock type in Last Chance canyon, Guadalupe mountains, New Mexico, USA. The rocks here are composed of horizontally to near horizontally interbedded carbonate and sandstone. This study focuses on first and second order channel sections where the streams have a lower channel steepness index (ksn) upstream and transition to a higher ksn downstream. We hypothesize that differences in bed thickness and rock strength influence ksn values, both directly by influencing bulk bedrock strength but also indirectly through the production of coarse sediment. We collected discontinuity intensity data (the length of bedding planes and fractures per unit area), Schmidt hammer rebound measurements, and measured the largest boulder at every 40-foot elevation contour to test this hypothesis. Bedrock and boulder minerology was determined using a lab-based carbonate dissolution method. High resolution orthomosaics and DEMs were generated from drone photos. The orthomosaics were used to map channel sections with exposed bedrock. The high-resolution DEMs were used to measure channel slope and hillslope relief. We find that discontinuity intensity is negatively correlated with Schmidt hammer rebound values. Channel steepness is higher where reaches are primarily incising through more thickly bedded carbonate bedrock. Where there is more thinly bedded sandstone rock exposed, channel steepness tends to be lower. Furthermore, the effect that rock properties have on channel morphology is confounded by sediment input from hillslopes. Thickly bedded rock units on surrounding hillslopes contribute larger sized colluvial sediment to the channels, and these reaches have higher ksn. Larger and more competent carbonate sediment armors both the carbonate and the more erodible sandstone and dampens the negative effect sandstone bedrock has on channel steepness. We believe that in the relatively steep, high ksn downstream channel sections slope is primarily controlled by the coarse alluvial cover. We further posit that the upstream low ksn reaches have a baselevel that is essentially fixed by the steep downstream reaches, resulting in a stable configuration where channel slopes have adjusted to lithologic differences and/or sediment armor. [ABSTRACT FROM AUTHOR]

The article discusses the lack of representation of Latine scholars in the Earth sciences and the barriers they face, including discrimination, language barriers, and funding limitations. To address these challenges, the authors established the Code to Communicate (CoCo) program, which offers bilingual training in Python programming and science communication. CoCo recruits a diverse cohort of Latine participants and provides comprehensive training in Python libraries and SciComm strategies. The program has received positive feedback from participants, who reported increased confidence in coding and appreciation for the bilingual nature of the program. The article concludes by highlighting the professional development opportunities and transformative power of collaboration offered by CoCo. [Extracted from the article]

A change in tectonics affects erosion rates across a mountain belt, leading to a period of non-steady sediment flux delivery downstream. The nonlinear relationship between tectonics and transient sediment delivery from an erosional catchment makes extraction of paleo-tectonic signals from stratigraphy challenging. We use a numerical landscape evolution model to explore how sediment flux from an erosional watershed responds to non-steady rock uplift. We focus on the time lag between the onset of a rock uplift change and the onset of a corresponding change in the sediment flux and the magnitude of the sediment flux relative to the steady rate. We observe that (1) sediment flux does not always record changes in the rock uplift rate when the duration of a rock uplift interval is less than 25% of landscape response time, or time for a landscape to transition from one steady state to another after a perturbation; (2) sediment flux response to variable rock uplift is positively correlated with the duration of rock uplift intervals; and (3) a nonlinear response between erosion rates and tectonic perturbations can result in increasing sediment flux through time even after rock uplift rate decreases. How quickly the sediment flux signal responds to a perturbation depends on how close the landscape was to steady state before the perturbation. These results illustrate conditions under which tectonic signals have the potential to be stored in the stratigraphic record or lost in an erosional system, and the importance of network dynamics for understanding signal propagation. [ABSTRACT FROM AUTHOR]

Quaternary sea-level cycles have caused dramatic depocentre shifts near the mouths of major rivers. The effects of these shifts on fault activity in passive margin settings is poorly known, as no studies have constrained passive margin fault throw-rate variability over 103 to 105 year time scales. Here we present 11 mean throw rates for the Tepetate-Baton Rouge fault zone along the northern Gulf of Mexico coast in southern Louisiana. These data were obtained by optically stimulated luminescence dating over time scales spanning the last interglacial to the late Holocene. The mean throw rate is ca. 0.22 mm year−1 during the late Holocene, ca. 0.03 mm year−1 during the last glacial and at least 0.07 mm year−1 during the last interglacial. Throw rates averaged over the late Pleistocene to present are spatially uniform within our study area. The temporal variability in throw rates suggests that shifts of the Mississippi River depocentre relative to this fault zone, driven by Quaternary sea-level cycles, may have imposed a significant control on fault activity. The late Holocene throw rate is at least in the order of magnitude smaller than the rates of land-surface subsidence in the Mississippi Delta, indicating that this fault zone is not a dominant contributor to subsidence in this region. [ABSTRACT FROM AUTHOR]