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A new, citizen science based, aurora observing and reporting platform has been developed with the primary aim of collecting auroral observations made by the general public to further improve the modeling of the aurora. In addition, the real-time ability of this platform facilitates the combination of citizen science observations with auroral oval models to improve auroral visibility nowcasting. Aurorasaurus provides easily understandable aurora information, basic gamification, and real-time location-based notification of verified aurora activity to engage citizen scientists. The Aurorasaurus project is one of only a handful of space weather citizen science projects and can provide useful results for the space weather and citizen science communities. Early results are promising with over 2,000 registered users submitting over 1,000 aurora observations and verifying over 1,700 aurora sightings posted on Twitter.

Citizen scientists share real-time auroral sightings to advance research.

"Science cafés" bring scientists and the public together for relaxed conversation in restaurants and coffee shops. The Teen Science Café Network shows that the concept isn't just for adults.

A major transition in the style of deformation of Kilauea volcano occurred during the period January 1982 through November 1983. Prior to 1983, the deformation was dominated by magma intrusions, rapid extension of the summit, and seaward movement of the south flank. The pattern of activity changed to magma eruption and slowed deformation of the volcanic edifice in January 1983. An earthquake swarm in the southwest rift zone in June 1982 and an intrusion of a large dike in the east rift zone in January 1983 prepared the volcano for the eruptive sequences that continue today. We estimate the sources of surface displacements associated with these events using a least squares nonlinear inversion technique and planar dislocations. The models are constrained with measurements of line length changes and of surface height changes from tide gauges, water wells, and spirit-level tilt data. Deformation associated with the 1982 earthquake swarm is best modeled as the emplacement of a steeply dipping dike in the upper and middle southwest rift zone extending from 2–3 km to 10–11 km depth with a width of ∼1–2 m. Tilt measurements gathered at the time of the earthquake swarm record a small deflation of Kilauea's summit; however, trilateration data indicate the summit was rapidly extending in 1982. The extension and our models are consistent with seaward slip of the south flank on a low-angle basal thrust fault. Dislocation models of the January 1983 dike intrusion yield a 14- to l5-km-long dike along the zone of observed ground rupture. The dike extends from just below the surface to the region of the most intense rift zone seismicity at 4–5 km depth. A strong nonlinear relationship among height, dip, and width results in a suite of models that explain the data equally well. Tests of parameter sensitivity indicate that the dike width and height are the least constrained parameters; the best fit average width ranges from 1.7 to 2.8 m. Our models also include a source of contraction at ∼5 km depth that produces 40 cm of ground subsidence near Makaopuhi, the point of initiation of the intrusion. This location is consistent with geochemical and seismic evidence that indicate magma is stored in the rift zone. Residual errors for all models indicate that substantial line-length changes are unexplained. Seaward motions of the south flank during 1982 and 1983 are not well modeled by simple dikes and summit deflations; however, attempts to constrain low-angle faults in the south flank were only partly successful due to the limited extent of the geodetic networks.

The 1989 Loma Prieta earthquake was an oblique thrusting event that raptured a moderately dipping fault that is subparallel to the San Andreas fault. Rupture initiated at 18 km and propagated both updip and bilaterally. Seismic and geodetic studies indicate that rupture terminated between 8 and 5 km depth. We examine the role of the elastic properties of the crust as a mechanism for reducing stress in the upper crust and terminating rupture. We use linear elastic fracture mechanics and the finite element method to model the Loma Prieta fault rupture as a mode II and mode III shear crack in a layered elastic crust. Our analysis shows that a low-stress condition, generated in our models by a change in material properties in the upper crust, is capable of stopping rapture. We also examine the stress condition at the intersection of the San Andreas and Loma Prieta faults to determine the present state of stress and seismic hazard in the region. We find that the Loma Prieta fault in the upper crust is still closer to the point of failure than the San Andreas fault over the same depth. Rupture of the Loma Prieta fault did not increase the seismic hazard of the San Andreas fault within the crustal volume above the Loma Prieta rupture.

Prince Galitsin's invention of the electromagnetic seismograph in 1914 revolutionized the young science of seismology. Now, the venerable research instrument is proving to have an equally powerful impact—in the arena of public education. Over the past 5 years, a number of initiatives have extended the boundaries of seismology research outside the ivory towers of research institutions and into America's schools, museums, and teaching colleges. These initiatives are built on the premise that educational seismology offers a special opportunity for capturing students' innate curiosity for natural phenomena in the world around them, and that this curiosity can be used to teach a wealth of fundamental principles of physics and Earth science. These school-based seismograph stations, now numbering in the hundreds, are demonstrating a growing potential to contribute both to science education and scientific research.

It is both an honor and a privilege to present Michael Mayhew as the 2007 recipient of the AGU Excellence in Geophysical Education Award. I do so on behalf of the geosciences community and the dozens of geoscientists who wrote letters documenting the sustained commitment and impact Mike has had on geoscience education. He is highly deserving of this recognition because his contributions to geophysical education have resulted in (1) a significant and long-lasting cultural change in the community such that geophysical education is embraced and promoted by scientists across the discipline; and (2) the development of a vibrant and highly successful geophysical education research community dedicated to advancing understanding of how we teach and learn about Earth.

A growing challenge facing college Earth science instructors is how to maximize learning in large, introductory lecture courses. These courses cover a great deal of information, yet students' gains in understanding science concepts and processes are often limited. Research shows that real learning occurs when students investigate scientific questions first hand [Halloun and Hestenes, 1985; DeLaughter et al., 1998; Kusnick, 2002] and faculty are able to challenge students' preconceived notions about Earth. Inquiry the process of seeking knowledge through questioning and investigations, is the most effective teaching method [NRC, 1996; Dykstra, 1997], but it can be challenging to implement in large lecture courses.

We analyze the conditions for nucleation of a dip-slip fault in intact crust and its subsequent growth using linear elastic fracture mechanics and the finite element method. We assume a fault can be modeled as a mode II shear crack in a layered elastic crust, and we investigate fault behavior under conditions of a variable dip and shear fracture energy. Two shear fracture energy gradients, Gc, were evaluated; both have surface values of 1 × 105 J/m2 and increase linearly to values of 1 × 106 or 1 × 107 J/m2 at 15 km depth, the base of the seismogenic zone. We assume that the vertical and horizontal components of the gravitational stress are both equal to the lithostatic load, effectively removing them from the calculation of shear stress on the fault Strain required for failure varied with respect to shear fracture energy gradient and rupture direction but not with dip. Rupture upward from the base of the seismogenic zone required more than twice the initial strain to cause fault growth and would result in very large earthquakes. Rupture downward in models associated with the higher Gc gradient resulted in stable growth of the fault; that is, additional strain was needed to allow for continuous fault growth from the surface to the base of the seismogenic zone. We suggest that fault nucleation and growth are a stable process which would preferentially occur by rupturing downward under stable conditions. Rerupturing of an established fault may initiate at depth or the surface depending on the degree of healing between rupture events and the tectonic stress available. A vast majority of shallow crustal earthquakes nucleate at the base of the seismogenic zone and rupture upwards. This suggests that most events are a reactivation of an old established fault and not growth of a new or developing fault.