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Despite their global societal importance, the volumes of large-scale volcanic eruptions remain poorly constrained. Here, we integrate seismic reflection and P-wave tomography datasets with computed tomography-derived sedimentological analyses to estimate the volume of the iconic Minoan eruption. Our results reveal a total dense-rock equivalent eruption volume of 34.5 ± 6.8 km³, which encompasses 21.4 ± 3.6 km³ of tephra fall deposits, 6.9 ± 2 km³ of ignimbrites, and 6.1 ± 1.2 km³ of intra-caldera deposits. 2.8 ± 1.5 km³ of the total material consists of lithics. These volume estimates are in agreement with an independent caldera collapse reconstruction (33.1 ± 1.2 km³). Our results show that the Plinian phase contributed most to the distal tephra fall, and that the pyroclastic flow volume is significantly smaller than previously assumed. This benchmark reconstruction demonstrates that complementary geophysical and sedimentological datasets are required for reliable eruption volume estimates, which are necessary for regional and global volcanic hazard assessments. 

Abstract The global pesticide complex has transformed over the past two decades, but social science research has not kept pace. The rise of an enormous generics sector, shifts in geographies of pesticide production, and dynamics of agrarian change have led to more pesticide use, expanding to farm systems that hitherto used few such inputs. Declining effectiveness due to pesticide resistance and anemic institutional support for non-chemical alternatives also have driven intensification in conventional systems. As an inter-disciplinary network of pesticide scholars, we seek to renew the social science research agenda on pesticides to better understand this suite of contemporary changes. To identify research priorities, challenges, and opportunities, we develop the pesticide complex as a heuristic device to highlight the reciprocal and iterative interactions among agricultural practice, the agrochemical industry, civil society-shaped regulatory actions, and contested knowledge of toxicity. Ultimately, collaborations among social scientists and across the social and biophysical sciences can illuminate recent transformations and their uneven socioecological effects. A reinvigorated critical scholarship that embraces the multifaceted nature of pesticides can identify the social and ecological constraints that drive pesticide use and support alternatives to chemically driven industrial agriculture. 

This article develops a dialogue between agrarian political economy, critical commodity chains research, and chemical geographies through a case study of the world’s most widely used agrochemical: glyphosate, commonly known as Monsanto’s Roundup. In the 1980s, glyphosate triumphed as a benign biocide that promised both safety and effectiveness. This construct made possible a capitalist agricultural assemblage characterized by chemical pervasiveness, first as a chemical replacement for mechanical tillage and since the 1990s as the chemical input for genetically modified seed packages. The ubiquity that characterizes the glyphosate assemblage is also a geography of uneven development comprising shifting firm networks, policies, and trade. Central to this assemblage since 2000, yet largely ignored, is the outsized expansion of second- and third-tier generic pesticide producers, especially in China, for whom glyphosate is part of a network entry and upgrading development strategy. Today, the glyphosate assemblage faces unprecedented challenges from weed resistance and health controversies. Whether and how the herbicide assemblage restabilizes will be determined by the complex environmental and developmental challenges of chemical agriculture and pervasive chemicals broadly, which highlights the need for a transdisciplinary dialogue that cuts across these domains. 

Abstract We have successfully constructed and tested a new, portable, Hybrid Lister‐Outrigger (HyLO) probe designed to measure geothermal gradients in submarine environments. The lightweight, low‐cost probe is 1–3 m long and contains 4–12 semiconductor temperature sensors that have a temperature resolution of 0.002°C, a sample rate of <2 s, and a maximum working depth of ~2,100 m below sea level (mbsl). Probe endurance is continuous via ship power to water depths of ~700 mbsl or up to ~1 week on batteries in depths >500 mbsl. Data are saved on solid‐state disks, transferred directly to the ship during deployment via a data cable, or transmitted via Bluetooth when the probe is at the sea surface. The probe contains an accelerometer to measure tilt, internal pressure, temperature, and humidity gauges. Key advantages of this probe include (1) near‐real‐time temperature measurements and data transfer; (2) a low‐cost, transportable, and lightweight design; (3) easy and rapid two‐point attachment to a gravity corer, (4) short (3–5 min) thermal response times; (5) high temporal/spatial resolution; and (6) longer deployment endurance compared to traditional methods. We successfully tested the probe both in lakes and during sea trials in May 2019 offshore Montserrat during the R/V Meteor Cruise 154/2. Probe‐measured thermal gradients were consistent with seafloor ocean‐drilling temperature measurements. Ongoing probe improvements include the addition of real‐time bottom‐camera feeds and long‐term (6–12 months) deployment for monitoring. 

Abstract First reported in the 1960s, offshore freshened groundwater (OFG) has now been documented in most continental margins around the world. In this review we compile a database documenting OFG occurrences and analyze it to establish the general characteristics and controlling factors. We also assess methods used to map and characterize OFG, identify major knowledge gaps, and propose strategies to address them. OFG has a global volume of 1 × 10⁶ km³; it predominantly occurs within 55 km of the coast and down to a water depth of 100 m. OFG is mainly hosted within siliciclastic aquifers on passive margins and recharged by meteoric water during Pleistocene sea level lowstands. Key factors influencing OFG distribution are topography‐driven flow, salinization via haline convection, permeability contrasts, and the continuity/connectivity of permeable and confining strata. Geochemical and stable isotope measurements of pore waters from boreholes have provided insights into OFG emplacement mechanisms, while recent advances in seismic reflection profiling, electromagnetic surveying, and numerical models have improved our understanding of OFG geometry and controls. Key knowledge gaps, such as the extent and function of OFG, and the timing of their emplacement, can be addressed by the application of isotopic age tracers, joint inversion of electromagnetic and seismic reflection data, and development of three‐dimensional hydrological models. We show that such advances, combined with site‐specific modeling, are necessary to assess the potential use of OFG as an unconventional source of water and its role in sub‐seafloor geomicrobiology.