Lake-effect snow as the dominant control of mesic-forest distribution in Michigan, USA

1Recent studies demonstrated the sensitivity of northern forest ecosystems to changes in the amount and duration of snow cover at annual to decadal time scales. However, the consequences of snowfall variability remain uncertain for ecological variables operating at longer time scales, especially the distributions of forest communities. 2The Great Lakes region of North America offers a unique setting to examine the long-term effects of variable snowfall on forest communities. Lake-effect snow produces a three-fold gradient in annual snowfall over tens of kilometres, and dramatic edaphic variations occur among landform types resulting from Quaternary glaciations. We tested the hypothesis that these factors interact to control the distributions of mesic (dominated by Acer saccharum, Tsuga canadensis and Fagus grandifolia) and xeric forests (dominated by Pinus and Quercus spp.) in northern Lower Michigan. 3We compiled pre-European-settlement vegetation data and overlaid these data with records of climate, water balance and soil, onto Landtype Association polygons in a geographical information system. We then used multivariate adaptive regression splines to model the abundance of mesic vegetation in relation to environmental controls. 4Snowfall is the most predictive among five variables retained by our model, and it affects model performance 29% more than soil texture, the second most important variable. The abundance of mesic trees is high on fine-textured soils regardless of snowfall, but it increases with snowfall on coarse-textured substrates. Lake-effect snowfall also determines the species composition within mesic forests. The weighted importance of A. saccharum is significantly greater than of T. canadensis or F. grandifolia within the lake-effect snowbelt, whereas T. canadensis is more plentiful outside the snowbelt. These patterns are probably driven by the influence of snowfall on soil moisture, nutrient availability and fire return intervals. 5Our results imply that a key factor dictating the spatio-temporal patterns of forest communities in the vast region around the Great Lakes is how the lake-effect snowfall regime responds to global change. Snowfall reductions will probably cause a major decrease in the abundance of ecologically and economically important species, such as A. saccharum.

Results of calculated surface air temperature anomaly of COSMOS Pliocene experiment 2 in NetCDF format

In this manuscript we describe the experimental procedure employed at the Alfred Wegener Institute in Germany in the preparation of the simulations for the Pliocene Model Intercomparison Project (PlioMIP). We present a description of the utilized Community Earth System Models (COSMOS, version: COSMOS-landveg r2413, 2009) and document the procedures that we applied to transfer the Pliocene Research, Interpretation and Synoptic Mapping (PRISM) Project mid-Pliocene reconstruction into model forcing fields. The model setup and spin-up procedure are described for both the paleo- and preindustrial (PI) time slices of PlioMIP experiments 1 and 2, and general results that depict the performance of our model setup for mid-Pliocene conditions are presented. The mid-Pliocene, as simulated with our COSMOS setup and PRISM boundary conditions, is both warmer and wetter in the global mean than the PI. The globally averaged annual mean surface air temperature in the mid-Pliocene standalone atmosphere (fully coupled atmosphere-ocean) simulation is 17.35 °C (17.82 °C), which implies a warming of 2.23 °C (3.40 °C) relative to the respective PI control simulation.

Accident trend monitoring and exploratory analysis. Final report.

National Highway Traffic Safety Administration, National Center for Statistics and Analysis, Washington, D.C.

Analysis of the future effects of the fuel shortage and increased small car usage upon traffic deaths and injuries. Final report. Executive summary.

Transportation Department, Office of Systems Engineering, Washington, D.C.

Foreign agricultural trade of the United States.

Mode of access: Internet.

Empirical crash injury modeling and vehicle-size mix. Technical report.

Mode of access: Internet.

Automobile marketing strategies, pricing, and product planning. Final report.

National Highway Traffic Safety Administration, Office of Research and Development, Washington, D.C.

The relationship of automobile characteristics to list prices and profit margins -- a preliminary analysis. Final report.

National Highway Traffic Safety Administration, Office of Research and Development, Washington, D.C.

Study of consumer automotive preference with regard to fuel economy measures.

National Highway Traffic Safety Administration, Washington, D.C.

1979 traffic fatalities - preliminary assessment.

Mode of access: Internet.

Vehicle crashworthiness and aggressiveness. Volume II: Measurement of aggressiveness for safety standards compliance.

Mode of access: Internet.

Automotive fuel economy contractors' coordination meeting - summary report.

Mode of access: Internet.

Yielding barrier test data base--a study of side impact cases in the multi-disciplinary accident investigation (MAI) file. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

Papers on car size - safety and trends. Technical report.

Mode of access: Internet.

Import passenger automobile weight projections 1979-1986: Mercedes-Benz, BMW, Volvo, BL Ltd. Final report.

National Highway Traffic Safety Administration, Washington, D.C.