Browsing by Author "Lehman, Clarence"
Now showing 1 - 6 of 6
- Results Per Page
- Sort Options
Item Climate Tracking: Applications of a Novel Technique to Sustainability(2012-07-24) Barnes, Richard; Lehman, Clarence; Williams, Shelby; Frelich, LeeClimate change has profound implications for the sustainability of society and the environment, yet estimates of climate change cover times scales which make results difficult to verify, are often computationally expensive to make, and have uncertainties which are not easily communicated, especially outside the area of computational meteorology and mathematics. We present a method of quantifying climate change over the past century and into the near‐future which bypasses many of these problems. Using historical weather data and a surface‐fitting algorithm, we are able to extract "climate velocities", representing the surface speed and direction of the climate for any location. Projections from these velocities can be used to extract possible future locations and direction‐of‐movement of biomes, biofuel hotspots, and agricultural productivity, with implications for conservation parkways, preemptive revegetation, agricultural policy.Item Ecology of Open Star Clusters(2012-06-13) Lehman, Clarence; Lehman, Fred; Barnes, Richard"Ecology of star clusters" examines the interactions of stars, and what can be gleaned from those interactions about the evolution and ultimate fate of star clusters large and small. Questions like: 1) What is the force that causes small star clusters to expand? 2) Why do the ancient globular clusters have many binary stars? 3) Why are close triple stars so rare?Item Efficient Algorithms for Geographic Watershed Analysis(2012-07-03) Barnes, Richard; Lehman, Clarence; Mulla, David; Galzki, Jacob; Wan, Haibo; Nelson, JoelThis project is to analyze where wetlands and other vegetated buffers can be placed on the landscape to intercept drain waters and help purify them before they reach the natural watershed. The computational problem comes because new LIDAR images have expanded the resolution of geographic digital elevation models (DEMs) up to a thousandfold or more. This in turn has taxed the ability of existing algorithms to process the expanded datasets. Here we explain the project and present new efficient algorithms for parallel and scalar processing that reduce run-times from days on ordinary computers to minutes or second using the new algorithms in a parallel supercomputing environment.Item New Rules for Simulation and Analysis in Ecology, Epidemiology, and Elsewhere(2012-06-13) Lehman, Clarence; Keen, AdrienneAn invisible "phase change" has recently re-shaped computation, in only a few years. Vast memories allow new modeling methods–still being invented and deployed. We apply such methods to epidemiology and ecology, outlined here.Item Quantitative Ecology: A New Unified Approach(University of Minnesota Libraries Publishing, 2019-07) Lehman, Clarence; Loberg, Shelby; Clark, AdamQuantitative Ecology introduces and discusses the principles of ecology from populations to ecosystems including human populations, disease, exotic organisms, habitat fragmentation, biodiversity and global dynamics. The book also reformulates and unifies ecological equations making them more accessible to the reader and easier to teach.Item Was Wright Right? Reconsidering the Adaptive Landscape(2013-04) Shinn, Maxwell; Lehman, Clarence