To better understand the implications of anthropogenic climate change for three major Mid-Atlantic estuaries (the Chesapeake Bay, the Delaware Bay, and the Hudson River Estuary), we analyzed the regional output of seven global climate models. The simulation given by the average of the models was generally superior to individual models, which differed dramatically in their ability to simulate twentieth-century climate. The model average had little bias in its mean temperature and precipitation and, except in the Lower Chesapeake Watershed, was able to capture the twentieth-century temperature trend. Weaknesses in the model average were too much seasonality in temperature and precipitation, a shift in precipitation's summer maximum to spring and winter minimum to fall, interannual variability that was too high in temperature and too low in precipitation, and inability to capture the twentieth-century precipitation increase. There is some evidence that model deficiencies are related to land surface parameterizations. All models warmed over the twenty-first century under the six greenhouse gas scenarios considered, with an increase of 4.7 ± 2.0 • C (model mean ± 1 standard deviation) for the A2 scenario (a medium-high emission scenario) over the Chesapeake Bay Watershed by 2070-2099. Precipitation projections had much weaker consensus, with a corresponding increase of 3 ± 12% for the A2 scenario, but in winter there was a more consistent increase of 8 ± 7%. The projected climate averaged over the four best-performing models was significantly cooler and wetter than the projected seven-model-average climate. Precipitation projections were within the range of interannual variability but temperature projections were not. The implied research needs are for improvements Climatic Change (2009) 95:139-168 in precipitation projections and a better understanding of the impacts of warming on streamflow and estuarine ecology and biogeochemistry.

For most residents in northern temperate zones, the most direct economic impact of global climate change is likely to be changes in home heating and cooling (HC) expenses, estimates of which should be of widespread interest. These residents are increasingly likely to make HC decisions (e.g. switches to electric heat, thermostat settings, conservation investments and behavioral change) in a wider context. The question turns from 'will projected climate change reduce my HC bills?' to 'how will projected climate change, with and without these various actions, affect my HC bills, my total energy use and my greenhouse gas emissions?' We modeled these 3 variables (HC expense, energy use and GHG emissions) on average households in 13 states in the northeastern United States under projected climate change alone, and under projected climate change with 3 modeled choices: increasing use of air-conditioners (AC); switching from petroleum-derived fuels to electric heating; and investing in insulation and efficiency upgrades. High climate change was projected to reduce annual HC expenses for average households in each state, the effect increasing through the century. These savings varied with ratios of heating degree-day to cooling degree-day changes, and with ratios of petroleum-derivative heating to electric heating households; both ratios varied along a north-south gradient in this region. Increasing AC use increased total energy use and CO 2 emissions more than it did expenses. Fuel-switching increased the first 2 more than it reduced the third. Upgrades provided the greatest savings in all 3 variables under low and high climate change. Effective energy policies and effective communication with energy users both require require explicit investigation of HC intensities at the household level, and modeling of conservation behaviors as well as purchased upgrades.

Diatomaceous sediments of California host large reserves of oil and gas tut are incompletely exploited. The matrix of these sediments is comprised largely of the frustules of diatoms (microscopic marine plants). Punctae in the frustules are responsible for the high porosities Punctae in the frustules are responsible for the high porosities characteristic of diatomites (up to 70 vol.%), but because of the very small size of the pores, permeabilities are low (commonly around 1 md). Furthermore, the oil contained in the reservoirs is often either immature or heavily biodegraded, hence viscous. In order to test the feasibility of applying in-situ combustion techniques to diatomaceous reservoirs, a laboratory test was conducted for a section fo core taken in the south plunge of the anticline in the Lest Hills field of the San Joaquin Valley in California. During the experiment, a fast stream plateau, good oxygen utilization, and an unusual front were observed. Fingering caused formation of a second front downstream. This finger stabilized and later became very hot (1600F). Velocity of front movement through the core almost doubled after the two fronts joined. API gravity of the oil extracted from the core ranged between 28 and 45, compared to the original value of 28 API. Tests were conducted to compare the cores before and after combustion, using-scanning microscopy, powder x-ray diffraction, and extraction techniques. After burning, the sediments changed from dark brown to red in color as a result of oxidation of organic and iron phases. Small numbers of diatom frustules were transformed from amorphuos opol to quartz, with accompanying occlusion of Tore spaces. With the exception of the color change, however, the sediments remained largely unaltered. It is especially interesting to note that the kerogen within the sediments appears to supply a portion of the fuel required for combustion. Kerogen is detrital organic matter than can be burned but cannot be extracted easily from a core in the laboratory. Kerogen's presence could make in-situ combustion more economical and efficient than other EOR methods in diatomites. Introduction Diatomaceous sediments are composed mainly of diatom frustules of microscopic algae which comprise a large part of the marine planktonic flora. Diatom accumulations in a reducing environment are potential oil source rocks. Because diatomites have high porosities, they may also be reservoir rocks. Indeed, large diatomite oil reservoirs occur in California in the oil producing San Joaquin Valley and the coastal borderland. Diatoms are very fine-grained sediments ranging in diameter from tens to hundreds of microns, with a high porosity largely formed by microscopic punctae of individual frustules. The geometry of this microporosity punctae of individual frustules. The geometry of this microporosity results in excellent bulk porosities (as high as 70%) and poor permeabilities (as low as 1 md or less). permeabilities (as low as 1 md or less).In the Cenozoic, diatoms were an important component of earth's biota. During the Tertiary, active wrench tectonism altered the major organic-siliceous deposits in California. In the San Joaquin Valley, diatomite ultimately is preserved on the crests of structural features. Oil found in these shallow sediments is either immature or highly biodegraded and, hence, very viscous. It was not until the recent oil price increase that producing oil from diatomites became profitable. As a result, increased recovery efforts were undertake in areas of California where oil-saturated diatomites and cherts (the diagenetic end product of these microfloral accumulations) occur. Diatomite reservoirs are often highly fractured, significantly increasing permeabilities and improving recovery rates. Still, primary production from these reservoirs amounts to only about 5% of original oil production from these reservoirs amounts to only about 5% of original oil in place. Consequently, enhanced recovery methods must be used to make the venture economical.

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