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Climate change is one of the greatest challenges facing humanity, and we, as machine learning (ML) experts, may wonder how we can help. Here we describe how ML can be a powerful tool in reducing greenhouse gas emissions and helping society adapt to a changing climate. From smart grids to disaster management, we identify high impact problems where existing gaps can be filled by ML, in collaboration with other fields. Our recommendations encompass exciting research questions as well as promising business opportunities. We call on the ML community to join the global effort against climate change.

Slow earthquakes, including low-frequency earthquakes, tremor, and geodetically detected slow-slip events, have been widely detected, most commonly at depths of 40–60 km in active subduction zones around the Pacific Ocean Basin. Rocks exhumed from these depths allow us to search for structures that may initiate slow earthquakes. The evidence for high pore-fluid pressures in subduction zones suggests that they may be associated with hydraulic fractures (e.g., veins) and with metamorphic reactions that release or consume water. Loss of continuity and resulting slip at rates exceeding 10−4 m s–1 are required to produce the quasi-seismic signature of low-frequency earthquakes, but the subseismic displacement rates require that the slip rate is slowed by a viscous process, such as low permeability, limiting the rate at which fluid can access a propagating fracture. Displacements during individual low-frequency earthquakes are unlikely to exceed 1 mm, but they need to be more than 0.1 mm and act over an area of ~105 m² to produce a detectable effective seismic moment. This limits candidate structures to those that have lateral dimensions of ~300 m and move in increments of <1 mm. Possible candidates include arrays of sheeted shear veins showing crack-seal structures; dilational arcs in microfold hinges that form crenulation cleavages; brittle-ductile shear zones in which the viscous component of deformation can limit the displacement rate during slow-slip events; slip surfaces coated with materials, such as chlorite or serpentine, that exhibit a transition from velocity-weakening to velocity-strengthening behavior with increasing slip velocity; and block-in-matrix mélanges. [ABSTRACT FROM AUTHOR]

New geothermometry using laser‐Raman data on carbonaceous material from low and intermediate grade rocks on Santa Catalina Island, California, together with existing thermobarometric data, show that there is a quasi‐continuous increase in peak metamorphic temperature from 327 ± 8°C in lawsonite blueschist facies rocks at the lowest structural levels, through ∼433°C in overlying epidote blueschists, 546 ± 20°C in albite‐epidote amphibolite facies rocks, to 650–730°C in amphibolite facies rocks at the top of the sequence. Rocks of different metamorphic grade are separated from one another by tectonic contacts across which temperature increases by ∼100°C in each case. Previously published geochronological data indicate that peak metamorphism in the highest grade rocks at 115 Ma preceded deposition of blueschist facies metasediments by ∼15 million years, so that the present inverted grade sequence does not represent an original inverted temperature gradient. The present structure results from progressive underplating of oceanic rocks in a cooling subduction zone following a high‐T metamorphic event at 115 Ma. An inverted temperature gradient of ≥100°C/km across the subduction channel likely existed during the high‐T event, decreased during underplating, and reached zero by ∼90 Ma. Key Points: New geothermometry shows that high‐pressure rocks on Catalina define an inverted metamorphic temperature zonationThe zonation is disrupted, and the present structure does not represent an original inverted thermal gradientThe zonation formed by progressive underplating in a cooling subduction zone following a high‐T metamorphic event [ABSTRACT FROM AUTHOR]

The transition to and from juvenile justice settings is a complex and challenging process. Effectively preparing juvenile justice personnel to address the transition needs of incarcerated students is an essential aspect of reducing the negative effects of the school-to-prison pipeline. This article examines program and professional development challenges that should be addressed to provide effective juvenile justice transition services. It also provides a technology-based perspective to the professional development challenges that are inherent within juvenile justice.

Technology provides exciting possibilities to the challenge of professional development in correctional education. Virtual induction strategies that include mentoring and immediate feedback during instructional delivery are now viable, low-cost, and secure options for correctional settings. Readers will become familiar with essential components of Induction and the Virtual Coaching Model.

No culture associates individual worth with a career like the United States. For juvenile offenders, in particular offenders with disabilities, this presents a significant challenge. In addition, the requirements that have been imposed on all education through the No Child Left Behind Act (NCLB; 2001) make programming that is consistent with the needs of the juveniles with disabilities population a major challenge. The authors propose the development of a career-based model that is consistent with best practice and in line with the requirements of NCLB. A comprehensive model based upon a vocational assessment designed to determine the aptitude and interest of each student is the basis for the development of a career pathway for each youth. Programming to provide the needed skill development in the areas of vocational, literacy, and adjustment skills, as well as transition or aftercare services that include advanced vocational preparation, health, welfare, and mental health services are all vital needs in the development of a successful program. The authors discuss the political, training, and financial realities associated with this needed paradigmatic change.

Advocates using technology to provide assistance for youth during and after incarceration, emphasizing that community involvement in the transition process can be significantly enhanced with technology support links. Recommends visual visits with family members, counselors, and teachers back home as an important addition to treatment or continued education. (Author/GCP)

The characteristics of migrant students that place them at risk educationally are described and reasons for low special education delivery rates are examined. Guidelines for educational intervention are offered, with the goal of increasing migrant children's economic options and opportunities. Three methodologies are recommended: learning strategies, cooperative learning, and whole language. (JDD)

[1] Global studies of metamorphic core complexes and low-angle detachment faults have highlighted a fundamental problem: Since detachments excise crustal section, the relationship between the mylonitic rocks in their footwalls and the brittle deformation in their hanging walls is commonly unclear. Mylonites could either reflect ductile deformation related to exhumation along the detachment fault, or they could be a more general feature of the extending middle crust that has been 'captured' by the detachment. In the first case we would expect the kinematics of the mylonite zone to mirror the sense of movement on the detachment; in the second case both the direction and sense of shear in the mylonites could be different. The northern Snake Range d6collement (NSRD) is a classic Basin and Range detachment fault with a well-documented top-east of displacement. We present structural, paleomagnetic, geochronological, and geothermometric evidence to suggest that the mylonite zone below the NSRD locally experienced phases of both east- and west-directed shear, inconsistent with movement along a single detachment fault. We therefore propose that the footwall mylonites represent a predetachment discontinuity in the middle crust that separated localized deformation above from distributed crustal flow below (localized-distributed transition (LDT)). The mylonites were subsequently captured by a moderately dipping brittle detachment that soled down to the middle crust and exhumed them around a rolling hinge into a subhorizontal orientation at the surface, producing the present-day NSRD. In this interpretation the brittle hanging wall represents a series of rotated upper crustal normal faults, whereas the mylonitic footwall represents one or more exhumed middle crustal discontinuities (LDTs). Citation: Cooper, F. J., J. P. Platt, E. S. Platzman, M. J. Grove, and G. Seward (2010), Opposing shear senses in a subdetachment mylonite zone: Implications for core complex mechanics, Tectonics, 29, TC4019, doi: 10.1029/2009TC002632.

The effectiveness of a computational fluid dynamics (CFD) commercial code to accurately predict the leakage rate for a windback seal was evaluated. The windback seal under consideration has a rectangular cavity and is similar in design to a gas tooth on stator annular labyrinth seal. The main difference is the windback seal has only one tooth, which continuously winds around the shaft like a screw thread. These seals are used in gas compressors to isolate the gas face seal from bearing oil. A purge gas is passed through the seal into the bearing housing. The helical design allows the seal to clear itself of any oil contamination. The objective is to determine if CFD simulations can be used along with a few experimental tests to study windback seals of this design. Comparison of measurement and predictions for a simple rectangular cavity windback seal shows predictions and measurements comparing very well with maximum differences of 5% for leakage rate. The variation of leakage with shaft speed and pressure ratio across the seal is accurately predicted by the CFD simulations. [DOI: 10.1115/1.2401205] Keywords: seal, windback, labyrinth, gas, compressor

[1] We investigate numerically the evolution of crustal and lithospheric thickness, thermal structure, topography, and strain rate of the Tibetan Plateau through time, using the thin viscous sheet approach. We show that lithospheric mantle must have been removed from beneath Tibet to explain the present surface elevation and lack of regional surface slope. In the absence of this removal, the modeled topography reaches a maximum elevation of

New Lu-Hf garnet growth ages from high-pressure rocks from the structurally lowest terrane (Nevado-Filabride Complex) in the Betic Cordillera of southern Spain indicate early Miocene subduction of continental crust, requiring significant revision of the timing and processes of orogeny in the western part of the Alpine orogenic system. Mafic eclogite and pelitic schist give Lu-Hf ages in the range 18-14 Ma, and fission-track data show that the terrane was exhumed by 12-8 Ma. The overlying terrane (Alpujarride Complex) shows early Tertiary high pressure-temperature metamorphism; this was followed by a thermal event that accompanied rapid crustal extension at 22-18 Ma, leading to the formation of the Alboran Sea backarc basin. The evidence therefore suggests two phases of continental subduction separated by a phase of large-scale intraorogenic extension. The two terranes are now separated by a mid-late Miocene low-angle extensional fault. The timing and paleogeographic setting suggest that the Nevado-Filabride terrane originally was close to the rifted South Iberian margin, and was subducted during westward motion of the extending upper terrane between the converging African and Iberian plates. Keywords: eclogite, geochronology, garnet, subduction, exhumation, Betic Cordillera.

We have investigated the kinematics of deformation in a sector of the Gibraltar arc in SW Spain, by synthesizing lineation data from major faults, the variation in structural trends, and palaeomagnetically determined vertical-axis rotations. The kinematic data show that transport directions throughout formation of the arc were consistently WNW, regardless of structural trend, which varies between 050 and 350 in the study area. The data suggest that this part of the Gibraltar arc can be explained simply by oblique convergence with a curved indenter. Taken together with other published data it appears likely that the variation in thrust transport direction within the Betic Cordillera as a whole may be considerably less than that in the Moroccan part of the arc. Unidirectional convergence, combined with the presence of palaeomagnetic rotations, implies either efficient overprinting of old, rotated lineations, and/or a convergence rate that is much greater than the rotation rate. Also required is a low degree of partitioning in the thrust wedge. The latter probably increases east of the study area, where the structural trend becomes more oblique to the transport direction, and major strike-slip faults occur. Keywords: Betic Cordillera, Spain, thrust faults, kinematics.