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The 21st century will be defined by challenges such as understanding and preparing for climate change and ensuring the availability of resources such as water and energy, which are issues deeply rooted in Earth science. Understanding Earth science concepts is critical for humanity to successfully respond to these challenges and thrive in the decades to come. As part of efforts to address this, a new program called the Earth Science Literacy Initiative (ESLI) was formed in 2008 with funding from the National Science Foundation (NSF). Its task was to create a succinct document outlining what citizens should know about Earth science. This document, called the Earth Science Literacy Principles (ESLPs), has applications in both public and private arenas. For example, the ESLPs have been used to define the core ideas of both a middle school textbook program and a new set of K-12 science education standards. The ESLPs, which are founded in a broad representation of the geoscience community, based upon current research, and endorsed by major government, industry, and academic geoscience organizations, represent an effort by the Earth science community to create a coherent and fundamental set of big ideas and supporting concepts that represent our fields.

Geophysical Research Letters (GRL) is the American Geophysical Union's premier journal of fast, groundbreaking communication. It rapidly publishes high-impact, letter-length articles, and it is the top-cited multidisciplinary geosciences journal over the past 10 years, with an impact factor that increased again in 2009, to 3.204. For manuscripts submitted to GRL, the median time to first and final decision is 23 and 27 days, respectivelya 35% improvement since 2007and the median time from submission to publication is 13 weeks for 90% of GRL papersa 25% improvement since 2007. Among high-impact publications in the geosciences, GRL has the fastest turnaround.

The Next Generation Science Standards (NGSS; Achieve 2014, 532; Figure 1A) represent a new approach to K-12 science education that involves the interweaving of three educational dimensions: Science and Engineering Practices (SEPs), Disciplinary Core Ideas (DCIs), and Crosscutting Concepts (CCCs). Unlike most preexisting state science standards for public education, these new standards focus on what students can do and not what they have memorized. The NGSS were motivated by the awareness within business and industry of the great need for better STEM education (science, technology, engineering, and mathematics) in order to meet future workforce demands for a global economy that is shifting toward higher technology levels. They were the result of a states-led effort, with twenty-six participating states involved in the writing; so far they have been adopted in full by sixteen states and the District of Columbia and adopted in part by several additional states and a large number of school districts. The NGSS have an increased focus on human-relevant content areas including the geosciences, which provide many new opportunities for the teaching of geography. The NGSS consist of a set of performance expectations for all U.S. K-12 students to complete, constructed in an integrated transdisciplinary manner for elementary school and broken out by discipline (Life Science, Physical Science, Earth and Space Science) for middle and high school. These performance expectations (PEs) represent a significant departure from the way science education has been previously assessed in the United States. To begin with, the PEs weave together eight practices of science and engineering (SEPs) with the content of science (DCIs), both within the context of seven broad crosscutting concepts (CCCs), as motivated by the National Research Council Report (NRC) A "Framework for K-12 Science Education" (NRC 2011; Figure 1B). The NGSS present an emphasis on science content that is relevant to human society and culture, resulting in a greater emphasis on earth science, which has a year's worth of standards for high school as well as middle school. The NGSS content is presented with a systems approach, as opposed to a disconnected set of facts to be memorized, and humans are an important part of this system. In addition, within the NGSS the line between science and engineering is intentionally blurred, and engineering concepts are integrated within all three dimensions. This means that the performance expectations go beyond the identification of human interactions with Earth's geographic surface to emphasize concepts of human sustainability through incorporation of the engineering design process. There is a great deal of enthusiasm within the national K-12 science education communities for implementation of the NGSS, and as a result there are a great number of resources being produced. The bipartisan not-for-profit states-led organization Achieve, which supervised the writing of the NGSS, has produced many resources listed at www. nextgenscience.org/resources.

In this article, Michael E. Wysession comments on the "Next Generation Science Standards" (NGSS), which are based on the recommendations of the National Research Council and represent a revolutionary step toward establishing modern, national K-12 science education standards. The NGSS involves significant changes from traditional standards at all levels for all of the sciences, integrating three dimensions of science content, science practices, and the crosscutting, big-picture themes of science. Nowhere are these changes more apparent than for the Earth and space sciences (ESS). Within the "Framework," Earth and space science content is parsed into three "Big Ideas," each of which is subdivided into components. ESS1 examines the space and solar systems; ESS2 examines the interconnections among Earth's many different systems of the geosphere, hydrosphere, atmosphere, cryosphere, and biosphere; and ESS3 focuses on the anthroposphere system, the important role that human civilization plays in affecting Earth's other systems. The NGSS performance expectations, and Earth and space sciences in particular, will pose special challenges to their implementation. Teachers may find many challenges: They may be unfamiliar with the aspects of engineering and technology newly integrated into the science curriculum; they may be unaccustomed to teaching from a practice-based approach as opposed to a concept focused approach; and they may be unused to connecting science content with overarching crosscutting concepts, with aspects of the nature of science, and with Common Core concepts of math and English language arts. This will all require significant professional development. None of these challenges is insurmountable, however, and many efforts are underway to help address them. However they are ultimately organized, structured, taught, and assessed in all of the states that adopt them, the NGSS provide a remarkable opportunity to realize the long-identified potential for Earth and space sciences to be taught in exciting, engaging, encompassing, and relevant manners from kindergarten through 12th grade.

High-velocity keels are present beneath stable continental interiors, but the maximum depth to which they extend, the degree to which they cool the surrounding mantle and the role in mantle flow, remains uncertain. Thermal anomalies throughout the eastern margin of the North American continental keel were investigated using images of seismic discontinuities. It is thought that the cold keel material and sub-keel down-wellings are confined largely to the upper mantle and can impinge on the transition zone only in localized areas.

A differential technique compares the arrival times of waves refracted across and diffracted around the core-mantle boundary to map the large-scale compressional-wave velocity variations within the D' thermal and chemical boundary layer. This map depicts the continent-sized variations at the core-mantle boundary that complements the shear-wave data. The diffracted waves provide an image of the D' layer, and the differential technique negates the effect of ray paths that are outside of D'. The results support a strong coupling between surface plate tectonics and the mantle base.

The face of our planet may owe many features to a mysterious layer called the core-mantle boundary that lies 3,000 kilometers below our feet What would become of the pages [...]

The lithosphere of Madagascar records a long series of tectonic processes. Structures initially inherited from the Pan-African Orogeny are overprinted by a series of extensional tectonic and magmatic events that began with the breakup of Gondwana and continued through to the present. Here, we present a Pn- tomography study in which Pn traveltimes are inverted to investigate the lateral variation of the seismic velocity and anisotropy within the uppermost mantle beneath Madagascar. Results show that the Pn velocities within the uppermost mantle vary by ±0.30 km s–1 about a mean of 8.10 km s–1. Low- Pn -velocity zones (<8.00 km s–1) are observed beneath the Cenozoic alkaline volcanic provinces in the northern and central regions. They correspond to thermally perturbed zones, where temperatures are estimated to be elevated by ∼100–300 K. Moderately low Pn velocities are found near the southern volcanic province and along an E–W belt in central Madagascar. This belt is located at the edge of a broader low S -velocity anomaly in the mantle imaged in a recent surface wave tomographic study. High- Pn -velocity zones (>8.20 km s–1) coincide with stable and less seismically active regions. The pattern of Pn anisotropy is very complex, with small-scale variations in both the amplitude and the fast-axis direction, and generally reflects the complicated tectonic history of Madagascar. Pn anisotropy and shear wave (SKS) splitting measurements show good correlations in the southern parts of Madagascar, indicating coherency in the vertical distribution of lithospheric deformation along Pan-African shear zone as well as coupling between the crust and mantle when the shear zones were active. In most other regions, discrepancies between Pn anisotropy and SKS measurements suggest that the seismic anisotropy in the uppermost mantle beneath Madagascar differs from the vertically integrated upper mantle anisotropy, implying a present-day vertical partitioning of the deformation. Pn anisotropy directions lack the coherent pattern expected for an incipient plate boundary within Madagascar proposed in some kinematic models of the region. [ABSTRACT FROM AUTHOR]