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Increases in vapor pressure deficit (VPD) have been hypothesized as the primary driver of future fire changes. The Coupled Model Intercomparison Project Phase 5 (CMIP5) models agree that western U.S. surface temperatures and associated dryness of air as defined by the VPD will increase in the 21st century for Representative Concentration Pathways (RCPs) 4.5 and 8.5. However, we find that averaged over seasonal and regional scales, other environmental variables demonstrated to be relevant to flammability, moisture abundances, and aridity—such as precipitation, evaporation, relative humidity, root zone soil moisture, and wind speed—can be used to explain observed variance in wildfire burn area as well or better than VPD. However, the magnitude and sign of the change of these variables in the 21st century are less certain than the predicted changes in VPD. Our work demonstrates that when objectively selecting environmental variables to maximize predictive skill of linear regressions (minimize square error on unseen data) VPD is not always selected and when it is not, the magnitude of future increases in burn area becomes less certain. Hence, this work shows that future burn area predictions are sensitive to what environmental predictors are chosen to drive burn area. Plain Language Summary: Since the 1980s, the western United States (U.S.) has warmed and wildfire burn area has increased. Most global climate models agree that the western United States will continue to warm and dry. If wildfire activity and aridity continue to change together in ways similar to the recent past, western U.S. fire activity will continue to dramatically increase through the 21st century. Global climate models are less certain regarding how other wildfire relevant environmental conditions may change. This work objectively selects linear combinations of wildfire‐relevant environmental conditions that best explain historical variability in western U.S. wildfire burn area. We then use climate model output to estimate how future wildfire burn area might change, as predicted by the objectively selected variables. We show that increases in burn area are likely as many climate models suggest the future will be drier. However, we find that future wildfire burn area estimates are lower whenever and wherever the importance of aridity is reduced. Key Points: Climate models agree that vapor pressure deficit will increase throughout the western United StatesVapor pressure deficit is not required to explain observed variability in past summer wildfire burn area for all western U.S. ecoregionsFuture wildfire burn area estimates are highest in regions where vapor pressure deficit explains substantial past variance in burn area [ABSTRACT FROM AUTHOR]

Abstract: A ca. 2010, 30m resolution map depicting annually tilled areas across the conterminous United States was developed. Input sources included fouryears, spanning 2008–2011, of annual national-level coverage Cropland Data Layer (CDL) land cover classifications as produced by the National Agricultural Statistics Service. Derived total land area under tillage from the aggregate CDL product equaled 112.8million hectares (278.7million acres). By comparison, the 2007 Census of Agriculture (CoA) produced an estimate of 122.9million hectares, suggesting the map is under representing tilled area by 10.1million hectares or 8.2%. Regression analysis using state-level summaries showed a strong, albeit biased, correlation (r-squared=0.99) between the CDL derived tilled area and the CoA information. Notable outliers were North Dakota and Montana. Comparisons of the CDL tilled map were also made against the 2006 National Land Cover Dataset (NLCD) land cover product’s Cultivated Crops category. Strong state-level regression agreement (r-squared=0.98) was also found between the NLCD and the CDL acreages, but the NLCD estimated 8.5% more area than the CDL and thus closely matched that of the CoA. However, significant pixel level differences were found between the CDL and the NLCD. Nationally 5.6% of the maps were in disagreement as to whether cultivated or not, a large proportion considering around a seventh of the country’s land area is tilled. States of Arkansas, Montana and Wisconsin had the largest absolute discrepancies between the NLCD and CDL. Accepting the CDL as reference showed a national level NLCD cropland commission error of 23.0% and omission error of 14.5%. Much of what is believed to be problematic in the NLCD could be explained by definitional issues having included alfalfa hay into their cultivated category for many areas. Ultimately, while it is likely that the CDL annually tilled area model is an underestimate of the true total, taken contextually in map form and adjusted for undercount bias it likely is the best available. [Copyright &y& Elsevier]

The article reports on a study of the physical design characteristics of a series of adult intensive care units between 1993 and 2003 in the U.S. Several negative characteristics have been found in these examples of best-practice adult intensive care units. Each unit in the study had received a design award from the Society of Critical Care Medicine, the American Association of Critical Care Nurses and the American Institute of Architects.

During the last retreat of the Laurentide Ice Sheet in North America, many proglacial lakes formed as continental drainage was impounded against the southern and western ice margin. Lake Agassiz was the largest of these lakes. The bathymetry of Lake Agassiz at the Herman and Upper Campbell beach levels – formed at about 11.5–11.0 ka and 9.9–9.5 ka, respectively – was computer modelled in this study by first collecting data for the isostatically-deformed paleowater planes of the two lake levels (derived from isobase lines constructed from beach elevations), and then subtracting these from the modern topography of the former lake floor. Pixels with dimensions of 1/30 × 1/30 of a degree were used in the model. Using these data, the area and volume of the lake were also calculated: at the Herman level these were ∼152 500 km2 and ∼13 100 km3 respectively; at the Upper Campbell level these were ∼350 400 km2 and ∼38 700 km3. Contour maps showing the paleobathymetry of both periods in the lake's history were also constructed. Determining the paleobathymetry and volume of Lake Agassiz is an important step in understanding the impact that the lake had on its surrounding environment and on the rivers, lakes, and oceans into which it flowed. [ABSTRACT FROM AUTHOR]