We present the results of two numerical models describing contributions of groundwater and heterogeneous heat sources to ice dynamics directly relevant to basal processes in East Antarctica. A two‐phase, one‐dimensional hydrothermal model demonstrates the importance of groundwater flow in vertical heat flux advection near the ice‐bed interface. Typical, conservative vertical components of groundwater volume fluxes (from either topographical gradients or vertically channeled flow) on the order of ±1–10 mm/yr can alter vertical heat flux by ±50–500 mW/m2 given parameters typical for the interior of East Antarctica. This heat flux has the potential to produce considerable volumes of meltwater depending on basin geometry and geothermal heat production. A one‐dimensional hydromechanical model demonstrates that groundwater is mainly recharged into saturated, partially poroelastic (i.e., vertical stress only; not coupled to a deformation equation) sedimentary aquifers during ice advance. During ice retreat, groundwater discharges into the ice‐bed interface, which may contribute to water budgets on the order of 0.1–1 mm/yr. We also present an estimated map of potentially heterogeneous heat flow provinces using radiogenic heat production data from East Antarctica and southern Australia, calculated sedimentary basin depths, and radar‐derived bed roughness. These are overlaid together to delineate the areas of greatest potential effect from these modeled processes on the ice sheet dynamics of the East Antarctic Ice Sheet.

In 2007, the United Nations' Intergovernmental Panel on Climate Change (IPCC) released its updated synthesis of climate change research, analysis of potential impacts to society, and options for mitigation. Recently, attention on ocean acidification and its consequences has gained momentum in the public sector, particularly since the release of the Kleypas and others (2006) report (for example, write-ups in Nature, August 2006, and The New Yorker, November 2006 issues). The report identifies declining oceanic pH and carbonate-ion concentrations as a consequence of increased atmospheric and surfaceocean carbon dioxide. The possible impact is providing questions that are amenable to both experimental and field study. Fabry (2003, as summarized in Kleypas andothers, 2006) postulated "if reduced calcification decreases a calcifying organism's fitness or survivorship, then such calcareous species may undergo shifts in their latitudinal distributions and vertical depth ranges as the CO 2 /carbonate chemistry of seawater changes."To date, very limited quantitative data exist with which to test this hypothesis, particularly in shelf environments. The continental shelves of Florida provide an ideal natural laboratory in which to test latitudinal (and depth) shifts in habitat ranges of calcifying organisms. Both the east and west Florida shelves extend from warm temperate to subtropical latitudes. Along this gradient, carbonate sedimentation changes from predominantly animal-produced shell hashes known as "heterozoan" carbonates that accumulate at rates of centimeters per 1,000 years, to subtropical reef environments where "photozoan" carbonate sediments are produced in association with photosynthesis, at rates that can exceed a meter per 1,000 years (hyper-calcification). Changes in either latitudinal or depth distributions of these benthic assemblages on the Florida shelves would provide convincing evidence of ecosystem-level effects of ocean acidification on calcifying organisms. The following report is a compilation of projects performed by students from the

Critical groundwater overdraft is one of the greatest water issues of our time. In California, decades of overdraft have resulted in the passage of the 2014 Sustainable Groundwater Management Act, which requires critically overdrafted groundwater basins to create groundwater sustainability plans for future groundwater management. Many managers are using managed aquifer recharge (MAR) in their overall sustainability portfolio, in an attempt to balance groundwater use. Soil maps have been used in the past to determine viability of managed aquifer recharge sites. However, soil maps do not account for the high permeability pathways that exist in the subsurface, which have the potential to provide high efficiency recharge to the water table. This paper emphasizes the utility of creating data dense fine resolution geostatistical models and generating many realizations of the subsurface, which can then be used for analysis to understand the variability in recharge potential for specific recharge sites. These geostatistical realizations were investigated using connectivity metrics to evaluate the spread of highly conductive pathways throughout the subsurface. Connectivity analyses of high conductivity pathways show confidence that the study site- three vineyards located in the floodplain between the Cosumnes River and Deer Creek in Elk Grove, CA - has the potential to provide efficient recharge to the water table. These connectivity analyses can be completed prior to running computationally expensive and time intensive groundwater models and can be used as a way to understand variance between realizations of these geostatistical models.

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