Increasing evidence indicates that forest disturbances are changing in response to global change, yet local variability in disturbance remains high. We quantified this considerable variability and analyzed whether recent disturbance episodes around the globe were consistently driven by climate, and if human influence modulates patterns of forest disturbance. We combined remote sensing data on recent (2001–2014) disturbances with in-depth local information for 50 protected landscapes and their surroundings across the temperate biome. Disturbance patterns are highly variable, and shaped by variation in disturbance agents and traits of prevailing tree species. However, high disturbance activity is consistently linked to warmer and drier than average conditions across the globe. Disturbances in protected areas are smaller and more complex in shape compared to their surroundings affected by human land use. This signal disappears in areas with high recent natural disturbance activity, underlining the potential of climate-mediated disturbance to transform forest landscapes.

Wildfires statistics for the conterminous United States (U.S.) are examined in a spatially and temporally explicit manner. We use a high-resolution data set consisting of 88,916 U.S. Department of Agriculture Forest Service wildfires over the time period 1970-2000 and consider wildfire occurrence as a function of ecoregion (land units classified by climate, vegetation, and topography), ignition source (anthropogenic vs. lightning), and decade. For the conterminous U.S., we ( i ) find that wildfires exhibit robust frequency-area power-law behavior in 18 different ecoregions; ( ii ) use normalized power-law exponents to compare the scaling of wildfire-burned areas between ecoregions, finding a systematic change from east to west; ( iii ) find that wildfires in the eastern third of the U.S. have higher power-law exponents for anthropogenic vs. lightning ignition sources; and ( iv ) calculate recurrence intervals for wildfires of a given burned area or larger for each ecoregion, allowing for the classification of wildfire regimes for probabilistic hazard estimation in the same vein as is now used for earthquakes.

According to projections by the United Nations, 60% of the world’s population will reside in urban areas by 2030. Studies of the ecology of cities and ecology in cities will therefore assume increasing relevance as urban communities seek to protect and/or enhance their ecological resources. Presently, the most serious threats to wildlife include the degradation and/or loss of habitats, the introduction and spread of problem species, water pollution, unsympathetic management, and the encroachment of inappropriate development. Climate change could add to these problems through competition from exotic species, the spread of disease and pests, increased summer drought stress for wetlands and woodland, and sea-level rise threatening rare coastal habitats. Earlier springs, longer frost-free seasons, and reduced snowfall could further affect the dates of egg-laying, as well as the emergence, first flowering and health of leafing or flowering plants. Small birds and naturalized species could thrive in the warmer winters associated with the combined effect of regional climate change and enhanced urban heat island. This article reviews the range of climate-related threats to biodiversity in the aquatic, intertidal and terrestrial habitats of urban areas. London is used as a case study to illustrate potential impacts, and to contend that ‘green spaces’ in cities could be used by planners to counter climate-related threats to biodiversity, as well as to improve flood control and air quality, and reduce urban heat island effects.