Landscape Partnership Resources Library
Global Warming, Elevational Range Shifts, and Lowland Biotic Attrition in the Wet Tropics
Many studies suggest that global warming is driving species ranges poleward and toward higher elevations at temperate latitudes, but evidence for range shifts is scarce for the tropics, where the shallow latitudinal temperature gradient makes upslope shifts more likely than poleward shifts. Based on new data for plants and insects on an elevational transect in Costa Rica, we assess the potential for lowland biotic attrition, range-shift gaps, and mountaintop extinctions under projected warming. We conclude that tropical lowland biotas may face a level of net lowland biotic attrition without parallel at higher latitudes (where range shifts may be compensated for by species from lower latitudes) and that a high proportion of tropical species soon faces gaps between current and projected elevational ranges.
Impacts Research Seen As Next Climate Frontier
Scientists hope the next U.S. president will devote more of the billion-dollar climate change research program to impacts SCIENCE VOL 322
From Death Comes Life: Recovery and Revolution in the Wake of Epidemic Outbreaks of Mountain Pine Beetle
Excerpt : “Part of the initial increase in nutrients and moisture under dead and dying trees is due to reduced uptake,” Rhoades says. “But the sick and dead trees are also losing needles that fall to the ground and help retain soil moisture. And, as trees decay, they release nutrients back into the system.”
More Intense, More Frequent, and Longer Lasting Heat Waves in the 21st Century
A global coupled climate model shows that there is a distinct geographic pattern to future changes in heat waves. Model results for areas of Europe and North America, associated with the severe heat waves in Chicago in 1995 and Paris in 2003, show that future heat waves in these areas will become more intense, more frequent, and longer lasting in the second half of the 21st century. Observations and the model show that present-day heat waves over Europe and North America coincide with a specific atmospheric circulation pattern that is intensified by ongoing increases in greenhouse gases, indicating that it will produce more severe heat waves in those regions in the future.
Homo economicus Evolves
Economic models can benefit from incorporating insights from psychology, but behavior in the lab might be a poor guide to real-world behavior.
The Technology Path to Deep Greenhouse Gas Emissions Cuts by 2050: The Pivotal Role of Electricity
Several states and countries have adopted targets for deep reductions in greenhouse gas emissions by 2050, but there has been little physically realistic modeling of the energy and economic transformations required. We analyzed the infrastructure and technology path required to meet California’s goal of an 80% reduction below 1990 levels, using detailed modeling of infrastructure stocks, resource constraints, and electricity system operability. We found that technically feasible levels of energy efficiency and decarbonized energy supply alone are not sufficient; widespread electrification of transportation and other sectors is required. Decarbonized electricity would become the dominant form of energy supply, posing challenges and opportunities for economic growth and climate policy. This transformation demands technologies that are not yet commercialized, as well as coordination of investment, technology development, and infrastructure deployment.
Global Change and the Ecology of Cities
Urban areas are hot spots that drive environmental change at multiple scales. Material demands of production and human consumption alter land use and cover, biodiversity, and hydrosystems locally to regionally, and urban waste discharge affects local to global biogeochemical cycles and climate. For urbanites, however, global environmental changes are swamped by dramatic changes in the local environment. Urban ecology integrates natural and social sciences to study these radically altered local environments and their regional and global effects. Cities themselves present both the problems and solutions to sustainability challenges of an increasingly urbanized world.
Impacts of Climatic Change and Fishing on Pacific Salmon Abundance Over the Past 300 Years
The effects of climate variability on Pacific salmon abundance are uncertain because historical records are short and are complicated by commercial har- vesting and habitat alteration. We use lake sediment records of 15N and biological indicators to reconstruct sockeye salmon abundance in the Bristol Bay and Kodiak Island regions of Alaska over the past 300 years. Marked shifts in populations occurred over decades during this period, and some pronounced changes appear to be related to climatic change. Variations in salmon returns due to climate or harvesting can have strong impacts on sockeye nursery lake productivity in systems where adult salmon carcasses are important nutrient sources.
Species invasions and extinction: The future of native biodiversity on islands
Predation by exotic species has caused the extinction of many native animal species on islands, whereas competition from exotic plants has caused few native plant extinctions. Exotic plant addition to islands is highly nonrandom, with an almost perfect 1 to 1 match between the number of naturalized and native plant species on oceanic islands. Here, we evaluate several alternative implica- tions of these findings. Does the consistency of increase in plant richness across islands imply that a saturation point in species richness has been reached? If not, should we expect total plant richness to continue to increase as new species are added? Finally, is the rarity of native plant extinctions to date a misleading measure of the impact of past invasions, one that hides an extinction debt that will be paid in the future? By analyzing historical records, we show that the number of naturalized plant species has increased linearly over time on many individual islands. Further, the mean ratio of naturalized to native plant species across islands has changed steadily for nearly two centuries. These patterns suggest that many more species will become naturalized on islands in the future. We also discuss how dynamics of invasion bear upon alternative saturation scenarios and the implications these scenarios have for the future retention or extinction of native plant species. Finally, we identify invasion-motivated research gaps (propagule pressure, time-lags to extinction, abundance shifts, and loss of area) that can aid in forecasting extinction and in developing a more comprehensive theory of species extinctions. birds plants species saturation
Population Dynamical Consequences of Climate Change for a Small Temperate Songbird
Predicting the effects of an expected climatic change requires estimates and modeling of stochastic factors as well as density-dependent effects in the population dynamics. In a population of a small songbird, the dipper (Cinclus cinclus), environmental stochasticity and density dependence both influenced the population growth rate. About half of the environmental variance was explained by variation in mean winter temperature. Including these results in a stochastic model shows that an expected change in climate will strongly affect the dynamics of the population, leading to a nonlinear increase in the carrying capacity and in the expected mean population size.
Southward movement of the Pacific intertropical convergence zone AD 1400–1850
Closing sentence of the abstract : We conclude that small changes in Earth’s radiation budget may profoundly affect tropical rainfall.
Is Global Warming Causing More, Larger Wildfires?
Higher spring and summer temperatures and earlier snowmelt are extending the wildfire season and increasing the intensity of wildfires in the western United States.
Road network density correlated with increased lightning fire incidence in the Canadian western boreal forest
This paper quantifies the influence of anthropogenic linear disturbances on fire ignition frequency in the boreal forests of western Canada. Specifically, we tested if linear features increase the frequency of lightning fires, and whether this relationship is affected by spatial resolution. We considered fires that ignited between 1995 and 2002 within a ∼67 000 km2 region of boreal mixed-wood forest in north-eastern Alberta where linear features are highly abundant and spatially heterogeneous. We constructed Poisson, Negative Binomial and Zero-Inflated Poisson models at two spatial resolutions (∼10 000 and ∼2400 ha), including covariates for linear feature densities, forest composition, weather–lightning indices and geography. We found a positive association between lightning fire frequency and road density; this association was consistent at both spatial resolutions. We suggest this occurs owing to increased availability of flammable fine fuels near roads. The effect was attributable neither to increased detectability of fires proximal to roads by human observers, nor to increased lightning strikes due to metallic infrastructure alongside roads or the topographic characteristics of road location. Our results suggest that, in the face of projected road developments in the region, the potential exists for important changes to the regional fire regime. Further research should elucidate the precise mechanisms in order to develop methods for mitigation.
Large Woody Debris and Salmonid Habitat in the Anchor River Basin, Alaska
A widespread and intense spruce beetle outbreak during the 1990s has killed most of the mature white spruce (Picea glauca) trees across many watersheds in south-central Alaska. To investigate the potential habitat impacts in a salmon stream, we characterized the current abundance and species composition of large woody debris (LWD), examined the linkages between LWD and salmonid habitat, and estimated changes in LWD abundance and associated pool habitat over time. LWD abundance was relatively low (97 pieces/km overall) and varied widely according to riparian vegetation typology, ranging from 15 pieces/km at sites with non- forested riparian zones to 170 pieces/km at sites adjacent to cottonwood forest. LWD provided significant fish cover in pools, especially in cottonwood forest stream reaches. LWD-formed pools were relatively rare (15% of total), but LWD abundance explained much of the variation in pool frequency (r2 = 0.86 in spruce forest reaches) and in the proportion of pool habitats (r2 = 0.85 in cottonwood forest reaches). We project the spruce beetle outbreak to result in a substantial net increase in LWD abundance over a 50-year span, peaking with 243% and 179% increases in LWD abundance for spruce forest and cottonwood forest stream reaches, respectively, in the year 2025. Concurrent with the peak in LWD abundance, our estimates show pool frequency in spruce forest reaches to reach 207% of current levels and the proportion of pools in cottonwood forest reaches to reach 167% of current levels, changes that correspond with substantially increased potential habitat for juvenile salmonids.
Habitat Refugia: A Practical Strategy to Conserve Biodiversity Under Climate Change
As climatic zones shift under climate change, many regions and habitats will slowly become climatically unsuit- able for some of the species that currently inhabit them. The availability of climate refugia - habitats and regions which are buffered from extremes in temperature and fluctuations in water availability, could allow some species to adapt to climate change in-situ, and facilitate dispersal and range shifts for other species. This information sheet explains the concepts behind habitat refugia with specific reference to how refugia can be used to protect and conserve terrestrial biodiversity faced with rapid climate change.
Refugia: identifying and understanding safe havens for biodiversity under climate change
Identifying and protecting refugia is a priority for conservation under pro- jected anthropogenic climate change, because of their demonstrated ability to facilitate the survival of biota under adverse conditions. Refugia are habitats that components of biodiversity retreat to, persist in and can potentially expand from under changing environmental conditions. However, the study and discussion of refugia has often been ad hoc and descriptive in nature. We therefore: (1) provide a habitat-based concept of refugia, and (2) evaluate methods for the identification of refugia.
Identifying refugia from climate change
This article highlights how the loose definition of the term ‘refugia’ has led to discrepancies in methods used to assess the vulnerability of species to the current trend of rising global temperatures. The term ‘refugia’ is commonly used without distinguishing between macrorefugia and microrefugia, ex situ refugia and in situ refugia, glacial and interglacial refugia or refugia based on habitat stability and refugia based on climatic stability. It is not always clear which definition is being used, and this makes it difficult to assess the appropriateness of the methods employed. For example, it is crucial to develop accurate fine-scale climate grids when identifying microrefugia, but coarse-scale macroclimate might be adequate for determining macrorefugia. Similarly, identifying in situ refugia might be more appropriate for species with poor dispersal ability but this may overestimate the extinction risk for good dispersers. More care needs to be taken to properly define the context when referring to refugia from climate change so that the validity of methods and the conservation significance of refugia can be assessed. Keywords Bioclimatic envelope models, climatic stability, conservation biogeography, cryptic refugia, ecological niche models, extinction risk, interglacial refugia, macrorefugia, microclimate, microrefugia.
The New Era Of Climate Risk Disclosure
In February of this year, the U.S. Securities and Exchange Commission made clear in no uncertain terms that corporations have a duty to disclose risks faced through poten- tial climate change. Yet many boards remain unaware of what constitutes a “material” climate risk, or just how broad the scope and potential impact truly are.
The impact of climate change on mental health
Climate change will shortly be assuming centre stage when Copenhagen hosts the United Nations Climate Change Conference in early December 2009. In Copenhagen, delegates will discuss the international response to climate change (i.e. the ongoing increase in the Earth’s average surface temperature) and the meeting is widely viewed as the most important of its kind ever held (http://en.cop15.dk/). International agreement will be sought on a treaty to replace the 1997 Kyoto Protocol. At the time of writing it is not known whether agreement will be reached on the main issues of reducing greenhouse gas emissions and financing the impacts of climate change, and it appears that the impact of climate change on mental health is unlikely to be on the agenda. We discuss here how climate change could have consequences for global mental health and consider the implications for future research and policy. Key words : Climate, mental disorder, mental health, global warming.
Importance of matrix habitats in maintaining biological diversity
Matrix management matters because formal reserve systems will never cover more than a small fraction of the globe.
