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The Prairie Pothole Region (PPR) of the north-central U.S. and south-central Canada contains millions of small prairie wetlands that provide critical habitat to many migrating and breeding waterbirds. Due to their small size and the relatively dry climate of the region, these wetlands are considered at high risk for negative climate change effects as temperatures increase. To estimate the potential impacts of climate change on breeding waterbirds, we predicted current and future distributions of species common in the PPR using species distribution models (SDMs). We created regional-scale SDMs for the U.S. PPR using Breeding Bird Survey occurrence records for 1971–2011 and wetland, upland, and climate variables....
Great Lakes fishery managers and stakeholders have little information regarding how climate change could affect the management of recreationally and commercially important fisheries, which have been valued at more than $7 billion USD annually. Our research focused on how climate change could influence fish habitat (including water temperature, ice cover, and water levels), phytoplankton production that supports fish biomass, and ultimately the growth and consumption of many important recreational and commercial fish species. This final report was produced for the NCCWSC-funded project Forecasting Climate Change Induced Effects on Recreational and Commercial Fish Populations in the Great Lakes.
Abstract (from http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-15-0199.1): Future snowfall and snowpack changes over the mountains of Southern California are projected using a new hybrid dynamical–statistical framework. Output from all general circulation models (GCMs) in phase 5 of the Coupled Model Intercomparison Project archive is downscaled to 2-km resolution over the region. Variables pertaining to snow are analyzed for the middle (2041–60) and end (2081–2100) of the twenty-first century under two representative concentration pathway (RCP) scenarios: RCP8.5 (business as usual) and RCP2.6 (mitigation). These four sets of projections are compared with a baseline reconstruction of climate from 1981 to 2000....
Abstract (from http://link.springer.com/article/10.1007%2Fs10980-015-0217-1): Context Tree species distribution and abundance are affected by forces operating across a hierarchy of ecological scales. Process and species distribution models have been developed emphasizing forces at different scales. Understanding model agreement across hierarchical scales provides perspective on prediction uncertainty and ultimately enables policy makers and managers to make better decisions. Objective Our objective was to test the hypothesis that agreement between process and species distribution models varies by hierarchical level. Due to the top-down approach of species distribution models and the bottom-up approach of process...
Abstract (from http://journals.ametsoc.org/doi/abs/10.1175/JHM-D-14-0082.1): A new technique for statistically downscaling climate model simulations of daily temperature and precipitation is introduced and demonstrated over the western United States. The localized constructed analogs (LOCA) method produces downscaled estimates suitable for hydrological simulations using a multiscale spatial matching scheme to pick appropriate analog days from observations. First, a pool of candidate observed analog days is chosen by matching the model field to be downscaled to observed days over the region that is positively correlated with the point being downscaled, which leads to a natural independence of the downscaling results...
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The habitats and food resources required to support breeding and migrant birds dependent on North American prairie wetlands are threatened by impending climate change. The North American Prairie Pothole Region (PPR) hosts nearly 120 species of wetland-dependent birds representing 21 families. Strategic management requires knowledge of avian habitat requirements and assessment of species most vulnerable to future threats. We applied bioclimatic species distribution models (SDMs) to project range changes of 29 wetland-dependent bird species using ensemble modeling techniques, a large number of General Circulation Models (GCMs), and hydrological climate covariates. For the U.S. PPR, mean projected range change, expressed...
Abstract: Globally, seabirds are vulnerable to anthropogenic threats both at sea and on land. Seabirds typically nest colonially and show strong site fidelity; therefore, conservation strategies could benefit from an understanding of the population dynamics and vulnerability of breeding colonies to climate change. More than 350 atolls exist across the Pacific Ocean; while they provide nesting habitat for many seabirds, they are also vulnerable to sea-level rise. We used French Frigate Shoals, the largest atoll in the Hawaiian Archipelago, as a case study to explore seabird colony dynamics and the potential consequences of sea-level rise. We compiled a unique combination of data sets: historical observations of islands...
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Identifying the climatic drivers of an ecological system is a key step in assessing its vulnerability to climate change. Theclimatic dimensions to which a species or system is most sensitive – such as means or extremes – can guide methodologicaldecisions for projections of ecological impacts and vulnerabilities. However, scientific workflows for combining climateprojections with ecological models have received little explicit attention. We review Global Climate Model (GCM)performance along different dimensions of change and compare frameworks for integrating GCM output into ecologicalmodels. In systems sensitive to climatological means, it is straightforward to base ecological impact assessments onmean projected...
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Sediment accumulation threatens the viability and hydrologic functioning of many naturally formed depressional wetlands across the interior regions of North America. These wetlands provide many ecosystem services and vital habitats for diverse plant and animal communities. Climate change may further impact sediment accumulation rates in the context of current land use patterns. We estimated sediment accretion in wetlands within a region renowned for its large populations of breeding waterfowl and migrant shorebirds and examined the relative roles of precipitation and land use context in the sedimentation process. We modeled rates of sediment accumulation from 1971 through 2100 using the Revised Universal Soil Loss...
Sensitivity analysis methods are used to identify measurements most likely to provide important information for model development and predictions. Methods range from computationally demanding Monte Carlo and cross-validation methods that require thousands to millions of model runs, to very computationally efficient linear methods able to account for interrelations between parameters that involve tens to hundreds of runs. Some argue that because linear methods neglect the effects of model nonlinearity, they are not worth considering. However, when faced with computationally demanding models needed to simulate, for example, climate change, the chance of obtaining insights with so few model runs is tempting. This work...
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Climate change poses major challenges for conservation and management because it alters the area, quality, and spatial distribution of habitat for natural populations. To assess species’ vulnerability to climate change and target ongoing conservation investments, researchers and managers often consider the effects of projected changes in climate and land use on future habitat availability and quality and the uncertainty associated with these projections. Here, we draw on tools from hydrology and climate science to project the impact of climate change on the density of wetlands in the Prairie Pothole Region of the USA, a critical area for breeding waterfowl and other wetland-dependent species. We evaluate the potential...
Abstract (from http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-14-00197.1): Using the hybrid downscaling technique developed in part I of this study, temperature changes relative to a baseline period (1981–2000) in the greater Los Angeles region are downscaled for two future time slices: midcentury (2041–60) and end of century (2081–2100). Two representative concentration pathways (RCPs) are considered, corresponding to greenhouse gas emission reductions over coming decades (RCP2.6) and to continued twenty-first-century emissions increases (RCP8.5). All available global climate models from phase 5 of the Coupled Model Intercomparison Project (CMIP5) are downscaled to provide likelihood and uncertainty estimates....
Bioclimatic models are the primary tools for simulating the impact of climate change on species distributions. Part of the uncertainty in the output of these models results from uncertainty in projections of future climates. To account for this, studies often simulate species responses to climates predicted by more than one climate model and/or emission scenario. One area of uncertainty, however, has remained unexplored: internal climate model variability. By running a single climate model multiple times, but each time perturbing the initial state of the model slightly, different but equally valid realizations of climate will be produced. In this paper, we identify how ongoing improvements in climate models can...
    map background search result map search result map Projected wetland densities under climate change: habitat loss but little geographic shift in conservation strategy Implications of climate change for wetland-dependent birds in the Prairie Potholes Region Vulnerability of Breeding Waterbirds to Climate Change in the Prairie Pothole Region Designing ecological climate change impact assessments to reflect key climatic drivers Sediment Accumulation in Prairie Wetlands under a Changing Climate: the Relative Roles of Landscape and Precipitation Projected wetland densities under climate change: habitat loss but little geographic shift in conservation strategy Implications of climate change for wetland-dependent birds in the Prairie Potholes Region Vulnerability of Breeding Waterbirds to Climate Change in the Prairie Pothole Region Designing ecological climate change impact assessments to reflect key climatic drivers Sediment Accumulation in Prairie Wetlands under a Changing Climate: the Relative Roles of Landscape and Precipitation